debrief MET Towers: A Collision Can Happen and it Has Happened…

debrief MET Towers: A Collision Can Happen and it Has Happened…
Transport
Canada
Transports
Canada
debrief
TP 2228E-38
(04/2011)
The spraying of crops by means of a specially adapted
aircraft is a common activity in rural areas. In order to
obtain the most effective application, the aircraft is often
flown at heights in the order of three to four meters
off the ground. The field, however, may also have a
meteorological (MET) tower, which is used to gather data
for analysis of the wind resource prior to the construction
of a windfarm. These towers have a tubular steel mast that
is held in position by sets of guy wires.
On June 29, 2010, an Air Tractor 502B was engaged in
aerial application near Portage la Prairie, Man., when it
collided with an unmarked metal wind power test pole
approximately 56 m high. The pilot elected to perform a
precautionary landing in a nearby field. Inspection of the
aircraft revealed damage to the propeller, right landing
gear, flap and wing leading edge, approximately 1.2 m from
the fuselage.
aviation safety letter
Feature
In most accidents involving carburetor icing, the pilot has not fully understood the carburetor heat
system of the aircraft and what occurs when it is selected. Moreover, it is difficult to understand the
countermeasures unless the process of ice formation in the carburetor is understood. Detailed descriptions
of this process are available in most good aviation reference publications and any AME employed on type
can readily explain the carburetor heat system. The latter is especially important because of differences in
systems. The pilot must learn to accept a rough-running engine for a minute or so as the heat melts and
loosens the ice which is then ingested into the engine.
mast
Flight Planning: A Critical Layer of Protection from Wake Turbulence
Instructor Refresher Courses Improve Flight Safety… and Renew your Rating
CARBURETOR ICING
D
U
FO
IT
Y
+10°
ID
0°
%
H
U
M
Serious icing - descent power
10
0
-10°
Both the mast and guy wires of a MET tower may be
quite difficult to see, depending on the ambient lighting
conditions and direction of approach. The photo below
illustrates this potential problem well.
-10°
Light icing - cruise or descent power
-18°
DEW POINT °C
G
C
LO
+20°
0°
+10°
+20°
+30°
MET towers are not normally at a height or location near
an aerodrome or recognized flight route, which would
require them to be either marked or lit, as stipulated in
Transport Canada CAR 621.19. For the same reason, they
would not be identified on navigational charts.
Debrief
AIR TEMP °C
(Source: Transport Canada Aeronautical Information Manual (TC AIM) Section AIR 2.3.)
COPA Corner: Practice Precautionary Approaches More Often
Underwater Egress Testimonials Validate Process
Major Accident Report: VFR into IMC Claims Seven
Optimistic and Ability Biases: “VFR flight into IMC won’t happen to me;
but if it does I can get out of it!”
Repair and Modification of Amateur-built Aircraft
MET Towers: A Collision Can Happen and it Has Happened…
Learn from the mistakes of others;
you’ll not live long enough to make them all yourself ...
"Debrief"
Prior to doing an aerial spraying, the pilot or operator
should always contact the field owner directly to find out
if there are any objects of concern in the field. If such a
tower cannot be readily seen under certain conditions,
there is a good chance it will not be detected by an air
reconnaissance alone. The pilot or operator should also
ask the field owner if there are any MET towers in
adjacent fields, over which the spray aircraft might make
necessary turns. -18°
+40°
NOTE: This chart is not valid when operating on automotive gasoline (MOGAS). Due to its higher
volatility, MOGAS is more susceptible to the formation of carburetor icing. In severe cases, ice may form
at outside air temperatures up to 20°C higher than with aviation gasoline (AVGAS).
The photo of the damage to the leading edge clearly
shows how fortunate this pilot was in terms of where
the aircraft struck the pole. Had the aircraft hit the pole
further out on the leading edge, aircraft control may
have been lost. According to the operator, the structural
integrity of the Air Tractor wing next to the fuselage is
believed to have allowed the aircraft to remain airworthy
and retain controllability. The top of the pole was damaged
and a galvanized guy wire ⅜ in. thick was severed. The
Transportation Safety Board of Canada issued a Class 5
report (A10C0101) on this occurrence.
Debrief
Debrief
+30°
Moderate icing - cruise power
or serious icing - descent power
In this Issue...
Reducing the Risk of Landing Accidents and Runway Overruns
The following chart provides the range of temperature and relative humidity which could induce
carburetor icing.
Serious icing - any power
TP 185E
Issue 2/2011
The June 2010 occurrence
guy wire
Feature
Carburetor Icing
Carburetor icing is a common cause of general aviation accidents. Fuel injected engines have very few
induction system icing accidents, but otherwise no airplane and engine combination stands out. Most
carburetor icing related engine failure happens during normal cruise. Possibly, this is a result of decreased
pilot awareness that carburetor icing will occur at high power settings as well as during descents with
reduced power.
by Eduard Alf, P.Eng., Visual Aids Technical Unit, Aerodromes and Air Navigation Division, Standards Branch, Civil Aviation,
Transport Canada
Debrief
Debrief
MET Towers: A Collision Can Happen and it Has Happened…
TC-1004093
36
ASL 2/2011
*TC-1004093*
Paul Marquis, Editor
Aviation Safety Letter
Transport Canada (AARTT)
330 Sparks Street, Ottawa ON K1A 0N8
E-mail: paul.marquis@tc.gc.ca
Tel.: 613-990-1289 / Fax: 613-952-3298
Internet: www.tc.gc.ca/ASL
Sécurité aérienne — Nouvelles est la version française
de cette publication.
© Her Majesty the Queen in Right of Canada,
as represented by the Minister of Transport (2011).
ISSN: 0709-8103
TP 185E
Publication Mail Agreement Number 40063845
Table of Contents
section
2
ASL 2/2011
— On September 24, 2010, the crew of a Cessna C180J
was performing training circuits on glassy water on
Little Chippewa Lake approximately 30 NM northwest
of South Indian Lake, Man. After several successful
circuits, the aircraft swung to the left when power was
applied for takeoff. The left float dug in and the aircraft
nosed over. The cabin filled quickly through the broken
windshield. The aircraft sank in approximately 10 ft of
water. The two occupants were uninjured and were able
to exit the aircraft safely. The left float was broken and
the aircraft was substantially damaged. The pilot-incommand had recently attended an underwater egress
training course. TSB File A10C0171.
— On September 26, 2010, an amphibious DHC-2
aircraft took off from Port McNeill aerodrome, B.C., on
a VFR flight to Rivers Inlet, B.C. As the weather was
marginal, the pilot became preoccupied with receiving
weather information on the radio immediately after
takeoff and did not retract the landing gear. Upon
arrival at Rivers Inlet, the pilot checked the landing gear
pressure but did not visually confirm the landing gear
position. On touch down, the aircraft overturned and
sank and the cabin filled with water. The four occupants
evacuated the aircraft successfully but none were wearing
a life jacket. As the aircraft was expected, a boat was
waiting and picked up all the occupants within five
minutes. There were no injuries, but the aircraft was
substantially damaged. TSB File A10P0308.
— On September 30, 2010, while conducting
circuits at the Kamloops Airport, B.C., the pilot of
a Piper PA‑31T Cheyenne inadvertently landed on
Runway 08 with the landing gear in the retracted
position. The pilot and passenger were uninjured but the
aircraft was substantially damaged. There was no fire.
TSB File A10P0312.
— On October 7, 2010, the pilot of a
Schleicher ASW‑15B glider was soaring in mountain
waves near Cowley, Alta. He was unable to return to
Cowley when he ran out of lift, and landed in rocky
terrain about 10 NM southwest of Cowley. The glider
was substantially damaged but the pilot was uninjured.
TSB File A10W0163.
— On October 10, 2010, a Piper PA28‑140
was on a VFR flight near the airport at
St-Georges de Beauce, Que. During the landing roll, it
seems that a wind squall caused the aircraft to swerve
to the left of Runway 24. The pilot, who was alone on
board, was unable to bring the aircraft back onto the
runway. The main wheel on the left side struck a runway
light and the left wing hit a runway sign. The aircraft
continued, crossing the ditch at the edge of the runway,
and came to a stop about 100 ft later. The pilot was not
injured. The left wheel and the propeller were damaged,
the nose wheel was torn off, and the root of the left
wing was knocked in. Reported winds were 270° at 8 kt.
Several witnesses reported a wind squall just before the
occurrence. TSB File A10Q0183.
— On October 19, 2010, a Hiller UH-12E helicopter
took off from Chetwynd, B.C. and flew to a job site
20 NM southwest. The job was to seed grass along a
pipeline. While seeding at an altitude of about 150 ft,
the engine (Lycoming IO-540) stopped. The pilot made
an autorotation into a clearing but landed hard and
rolled over. The helicopter was substantially damaged
and the pilot was uninjured. The 406 emergency locator
transmitter (ELT) was activated. TSB File A10P0337. ASL 2/2011
35
Regulations and You
Guest Editorial..................................................................................................................................................................3
Pre-Flight...........................................................................................................................................................................5
Flight Operations..............................................................................................................................................................9
Maintenance and Certification........................................................................................................................................19
Recently Released TSB Reports......................................................................................................................................23
Accident Synopses............................................................................................................................................................33
Debrief: MET Towers: A Collision Can Happen and it Has Happened…..............................................................36
The First Defence (poster)................................................................................................................................................Tear-off
Take Five: Carburetor Icing.............................................................................................................................................Tear-off
Regulations and You
page
— On September 22, 2010, a Cessna 172 on floats had
taken off from Lac du Sapin Croche, Que., for a local
flight. Upon its return, it landed on the water and then
taxied towards a cottage. When it was about 150 ft from
shore, a wind squall lifted the back part of the aircraft
and flipped it over. The pilot, who was alone on board,
was not injured. He was wearing a Mustang flotation
device and was able to swim to shore without difficulty.
The aircraft remained above water, suspended by its floats.
TSB File A10Q0161.
— On September 27, 2010, the pilot of a Cessna 152
was en route from Wawa, Ont. to Sioux Lookout, Ont.
The Sioux Lookout flight service station (FSS) received
a call from the pilot stating that he was out of fuel. The
pilot conducted a forced landing into a tilled field 6 NM
east of Sioux Lookout Airport. The aircraft impacted
the ground at a high angle and low velocity. The aircraft
was substantially damaged and the pilot was seriously
injured. Overflying aircraft reported a continuous and
strong emergency locator transmitter (ELT) signal.
They provided the coordinates of the site and directed
emergency personnel. The pilot was extricated from the
wreck and transported to hospital. TSB File A10C0174.
Recently Released TSB Reports
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injuries and the passenger was not injured. An
examination revealed that the left rudder cable had
broken as a result of excessive wear: it had been rubbing
against the floor and the steel guard on one of the pulleys.
The cable was also corroding at the point of the fracture
and the right cable was also showing signs of wear. The
diameter of the pulleys (1 in.) and that of the two rudder
cables was smaller than what is normally used. As is often
the case, the cable tension on the aircraft is provided
by return springs. When the left cable broke, the right
spring pulled on the right cable, which caused the yawing
to the right. TSB File A10Q0159.
Accident Synopses
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Accident Synopses
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To the Letter
Dave Turnbull
Most of the work done by NAC is related to the approval of aeronautical product designs and
modifications to those designs, by evaluating them against a set of design standards as required by regulations. Once
operating, the continuing airworthiness of those products is overseen, and corrective actions are mandated in cases
where design deficiencies that appear in service pose a threat to safety. NAC is also heavily involved in the evolution of
appropriate means and methods of compliance with the design standards, and is the core source of the technical input
required to develop new and amended versions of the design standards and associated guidance material. NAC is part of
an international community and is involved in various working groups and committees that collaborate to continuously
adapt and develop design standards and the interpretation of these standards.
Each design project undertaken by an applicant follows a process unique to a company’s design methodology. Evaluating
a design or design change against the standards is unique each time. It requires many highly subjective technical
assessments, and as such, it requires expert flight test and engineering knowledge and skills normally acquired through
significant experience in evaluating designs against international standards. NAC and Regional Aircraft Certification
personnel, along with the ministerial delegate community across the country, have this expertise, and the ongoing
interaction with applicants and delegates on these projects is essential to remaining current with evolving technology
and approaches to aircraft design.
Over the past several years, Transport Canada Civil Aviation’s (TCCA) oversight of the aviation industry has been
gradually moving to a systems-based approach, based on the existence of new regulations requiring certain segments
of the industry to have an approved safety management system (SMS). More recently, NAC have been busy working
on determining how a company’s SMS can include the design process, and how the oversight approach can evolve into
a more systems-based approach. This is in line with Transport Canada’s (TC) move to strengthen the way it conducts
oversight of Canada’s entire aviation industry. This gives rigor to the way TC manages safety, as well as to their own
surveillance model.
Oversight (in the context of aircraft certification) is defined in TC’s Program Activity Architecture (PAA) as, “service to
and surveillance of the aeronautical product design industry”. The service elements related to aircraft certification (such
as establishing appropriate standards, agreeing to acceptable means and methods of compliance, and issuing
approvals) are fundamental and will need to remain after the introduction of SMS to the design side of the business.
The surveillance elements today consist of a risk-based Level of Involvement (LOI) policy where TCCA engineers
interact with ministerial delegates during the certification projects, plus periodic audit activities (outside the context
of specific projects) of delegated entities, as well as continuing airworthiness monitoring of the Canadian fleet. When
an organization’s SMS includes the design piece, it is the audit side of NAC’s surveillance model, as well as how the
lessons learned from continuing airworthiness surveillance is fed back into the design SMS that will have to evolve.
Project‑based service and surveillance will need to live on in parallel and in balance with a new oversight model that
pertains to the company’s new SMS design elements. Current thinking is that neither a purely systems-based nor a
purely project-based oversight model will suffice.
Flight Operations
To enable this evolution in oversight in the area of aeronautical product design, organizations will need to hold a new
type of operational certificate, similar to an air operator certificate (AOC). A company’s overall SMS will include a
design assurance system that provides a level of certainty that the designs are safe, and that the company will make
sound and defendable determinations of compliance. It also means that the design industry will be accountable to TC
for the quality of these findings and the continuing airworthiness of approved products.
ASL 2/2011
Pre-Flight
Pre-Flight
As one of the more recent directors appointed to the Civil Aviation Management
Executive Board (CAMX), I am pleased to have the opportunity to contribute to this
issue of the Aviation Safety Letter (ASL). Let me start by explaining the basics of what the
National Aircraft Certification Branch (NAC) does. In doing so, I will also capture the main
duties of our engineering colleagues in the Aircraft Certification offices in the regions.
To the Letter
Flight Operations
Guest Editorial
Guest Editorial
guest editorial
3
Dave Turnbull
Director, National Aircraft Certification Branch
Transport Canada Civil Aviation
To the Letter
Guest Editorial
To the Letter
Clearly, there are many challenges ahead; however, these are also exciting times and I look forward to working together
to improve how we do business. Striking the proper balance between systems-based oversight and certification
project‑based oversight will be crucial and will require close attention. In the meantime, the NAC continues to carry out
its mandate, working directly with industry and international colleagues to support a very strong and ever-demanding
Canadian aeronautical design and manufacturing industry. According to the Aerospace Industries Association of
Canada, Canada exports over 80 percent of its aeronautical products in an industry sector that makes up nearly 5 percent
of our Gross Domestic Product. Getting speedy approvals from our foreign markets depends directly on the quality of
our own approval process. Our ultimate goal is to improve safety, which is a goal that we share with the industry.
Guest Editorial
Issuing this new kind of operational certificate will require NAC and its regional engineering colleagues to provide new
and additional services and surveillance related to a company’s SMS. Some can be derived from the existing delegation
system that has been in place in Canada since 1968. Others will be taken from other operational areas of aviation where
SMS is already in place. The systems approach to the design side of the organizations is aimed at promoting a sound
safety culture through robust design assurance processes and a positive reporting culture.
2010 David Charles Abramson Memorial (DCAM) Flight Instructor Safety Award
Pre-Flight
Flight Operations
The annual DCAM Award promotes flight safety by
recognizing exceptional flight instructors in Canada
4
Left to right: Wayne Gouveia, Board of Directors, ATAC;
William Sutherland; Jane Abramson.
and has brought much recognition and awareness
to the flight instructor community. Recognition of
excellence within this segment of our industry upholds
a safety consciousness that will hopefully be passed on
for many years to come.
The deadline for nominations for the 2011 award is
September 13, 2011. For details, please visit www.dcamaward.com.
ASL 2/2011
Flight Operations
“It goes this year to a young man whose
achievements to date and future potential shine full
of promise as a beacon for the future of aviation
safety in Canada” said Mrs. Abramson. “His strong
leadership, integrity, technical competence and
commitment to excellence were instrumental in
MFC successfully achieving the performance criteria
required for certification as an Approved Training
Organization (ATO) authorized to conduct flight
training in Canada. The requirement to operate a flight
training organization to the exacting ATO standards
is an essential pre-requisite for MFC and its partner,
CAE, to be able to conduct the first Multi-Crew Pilot
License (MPL) training program in North America.”
Pre-Flight
The recipient of the 2010 DCAM Flight Instructor
Safety Award is Mr. William Sutherland,
Manager of Corporate Safety & Quality, Moncton
Flight College (MFC), Dieppe, New Brunswick.
The award was presented to William on
November 8, 2010, by award founders Jane and
Rikki Abramson at the Air Transport Association
of Canada (ATAC) Annual General Meeting and
Tradeshow in Vancouver, British Columbia.
pre-flight
Guest Editorial
Reducing the Risk of Landing Accidents and Runway Overruns
by Martin J. Eley, Director General, Civil Aviation, Transport Canada
Regs
Day& you
in and
day out, week after week, thousands of
aircraft land in Canadian aerodromes without incident.
Unfortunately, this isn’t always the case. Air travel is a
complex issue and landing aircraft can be equally difficult.
With unpredictable factors such as weather conditions, the
surrounding terrain and human error, the fact remains that
accidents can and do happen.
The Transportation Safety Board (TBS) investigated
this accident and on March 16, 2010, they issued a
watchlist of items that highlight safety concerns or safety
recommendations made to Transport Canada (TC).
One of the watchlist items refers to landing accidents
and runway overruns. A runway overrun is an occurrence
where an aircraft departs from or lands on the end or one
side of the runway.
TC has taken a number of actions to reduce the risk of
landing accidents and runway overruns and to address the
TSB’s watchlist.
Regulations and standards
TC agrees that RESA is a vital component of its risk
reduction plan and is committed to conforming to the
International Civil Aviation Organization’s (ICAO)
150 m RESA standard, while assessing the potential
benefits of extending the RESA to 300 m. TC has
therefore tabled Notices of Proposed Amendment (NPA)
to the Canadian Aviation Regulations to adopt a 150 m
total RESA requirement. These NPAs were considered
at the Canadian Aviation Regulation Advisory
Council (CARAC) Technical Committee meeting, which
was held from November 15 to 17, 2010.
International cooperation
TC is an active participant in the ICAO’s Air Navigation
Commission, Aerodrome Panel and Aerodrome Design
Working Group. The purpose of this participation is to
develop and harmonize international standards that will
reduce runway overrun and undershoot accidents.
At the 2010 ICAO assembly, TC presented a working
paper on runway safety that addressed incursions and
excursions. At this same assembly, a proposal was made by
1
A regulatory amendment on safe winter runway
operations was published in the Canada Gazette Part I:
Notices and Proposed Regulations. The proposal would
require airport operators to develop standardized
procedures related to winter runway maintenance. The
ASL 2/2011
EMAS is an example of a ground arrestor system. EMAS is
located beyond the end of the runway. It is designed to stop
an overrunning aircraft by exerting deceleration forces on the
aircraft’s landing gear. The application of EMAS can mean the
difference between an accident and a minor incident. EMAS is
a soft ground arrestor. This type of arrestor deforms under the
weight of the aircraft tire as it runs over it. As the tires crush
the material, the drag forces decelerate the aircraft and bring it
to a safe stop. EMAS is popular in the U.S at airports that have
difficulties complying with FAA rules on runway safety.
Flight Operations
Since 2006, requirements have been in place governing
landings in low visibility conditions. These regulations
clearly set out the minimum conditions for landings
in poor visibility. This prohibits air operators from
attempting a landing when visibility is so poor that a
successful landing is unlikely.
Additionally, TP 312 – Aerodrome Standards and
Recommended Practices is being revised in cooperation with
industry experts. The updated document will address:
• providing additional visual aids for pilots to help assess
landing distances;
• harmonizing Canadian and international runway end
safety area (RESA) standards; and
• recognizing the engineered material arresting
system (EMAS)1 as an added measure to
increase safety.
Pre-Flight
Pre-Flight
On August 2, 2005, an Air France Airbus A340 was
unable to stop on runway 24L at Toronto’s Pearson
International Airport. The flight landed during reports
of exceptionally bad weather—severe winds, heavy rain,
and localized thunderstorms—and touched down further
along the runway than usual. The aircraft came to rest in a
nearby shallow ravine and burst into flames approximately
300 m past the end of the runway. There were 309 people
on board: 297 passengers (2 of whom were infants) and
9 crew members. Fortunately, everyone survived and
successfully evacuated the aircraft, with only 12 passengers
sustaining serious injuries.
proposal would also require accurate and timely reporting
of surface conditions at airports in winter. These measures
will lead to more reliable and safer transportation for
those using Canadian airports during the winter.
To the Letter
To the Letter
Not used
Flight Operations
Guest Editorial
Reducing the Risk of Landing Accidents and Runway Overruns.................................................................................. page 5
Flight Planning: A Critical Layer of Protection from Wake Turbulence...................................................................... page 6
Instructor Refresher Courses Improve Flight Safety… and Renew your Rating........................................................... page 7
Pre-flight
5
TC agreed with this proposal and noted that the
establishment of a runway safety program should strive
as much as possible to ensure that runway incursions and
runway excursions are studied and defined separately.
This would help to develop the best and most appropriate
measures for each type of occurrence.
ICAO is also organizing a Global Runway Safety
Symposium in 2011, in which TC looks forward
to participating.
Landing accidents and runway overruns are an
unfortunate reality in aviation. TC is committed to
ongoing studies and analyses to identify the hazards
and the dynamics that lead to these safety risks, as well
as continuing to take action to maintain a high level of
safety in the air, and on land. Guest Editorial
Guest Editorial
ICAO to establish runway safety programs to prevent and
mitigate runway accidents and incidents.
Flight Planning: A Critical Layer of Protection from Wake Turbulence
In recent years, NAV CANADA controllers have noticed a
number of discrepancies between the weight categories in
flight plans filed by air operators and the expected aircraft
weight category. Most of these discrepancies are not errors,
but even a small number of errors in filed flight plans
should raise vigilance on the part of all pilots, dispatchers
and air operators.
and to apply the
appropriate separation
standard as detailed
in MANOPS (NAV CANADA, Manual of Operations).
Turbulence category is determined by the aircraft
maximum certificated take-off mass and not by the actual
take-off weight of the aircraft.
Impact of an incorrect weight category
Sources of discrepancies
Air traffic controllers depend on accurate weight category
information in the flight plan to ensure safe wake
turbulence separation. Wake turbulence is turbulent air
behind an aircraft caused by any of the following:
Other aircraft may change categories due to certified
weight increases for specific mission aircraft (such as
AirTractor Model AT8T for agricultural or fire suppression
flights) or for temporary certified increases for ferry flights.
Wake turbulence is usually invisible, leaving pilots with
no warning that they are flying into turbulence. This is
the reason why, during takeoff and landing, air traffic
controllers provide standard separation for all departing
aircraft and for IFR traffic on approach.
The vortex characteristics of any given aircraft can
also be changed by extension of flaps or other wing
configuring devices as well as by a change in speed.
However, as the basic factor is weight, the vortex strength
increases proportionately.
6
One other aircraft of note is the B757, which, while
identified as a medium category aircraft, has an increased
separation requirement specific to that model due to wake
characteristics for following aircraft.
What can you do?
For aircraft types listed in more than one category in
ICAO Doc 8643, NAV CANADA controllers are not
permitted to modify the weight category unless the pilotin-command specifically identifies a weight category
different than the one filed.
If you are filing a flight plan, double-check the weight
category. Be sure that the filed weight category is reflective
of the type of flight, flight permit or certificate that you
are operating under, not the actual take-off weight of
the aircraft. Doing so will ensure that the appropriate
turbulence separation criteria is applied to your aircraft. ASL 2/2011
Flight Operations
Flight Operations
There are a number of different factors that will affect
the strength of the vortex, and how long it persists. The
strength of the vortex is governed by the weight, speed, and
shape of the wing of the generating aircraft.
In Canada, ICAO (International Civil Aviation
Organization) Doc 8643, Aircraft Type Designators, is
utilized to determine aircraft wake turbulence categories
ICAO Doc 8643 is very extensive, but within a specific
model there can be model variants that have different
take-off weights. While most would not be noticeable
to air traffic control (ATC), some models can (and do)
move from one turbulence category to another, such as
the KingAir Model 350 (B350) and the SW4, which are
shown as both light and medium (L/M).
Pre-Flight
Pre-Flight
(a) wing-tip vortices;
(b) rotor-tip vortices;
(c) jet-engine thrust stream or jet blast;
(d) rotor downwash;
(e) prop wash.
To the Letter
To the Letter
by Dave Rye, Manager, Area Control Centre Operations Moncton, NAV CANADA
Instructor Refresher Courses Improve Flight Safety… and Renew your Rating
Many instructors elect to renew their ratings by undergoing
a flight test, but there are, in fact, several different
options for renewing an instructor rating. According to
CAR 421.66, one way to renew an instructor rating is to
attend a Flight Instructor Refresher Course (FIRC). Many
instructors are unfamiliar with, or reluctant to use, this
method of renewal, so let’s take a look at what a FIRC is.
The FIRC originally began in 1951 as a
Transport Canada (TC) initiative. Over the years, the
program underwent several changes until its conclusion
in 2007. TC then granted the flight training industry
authority to conduct its own courses under General
Aviation Advisory Circular (GAAC) 421-001.
In addition to renewing an instructor rating, the FIRC
is an outstanding avenue for professional development,
which addresses the above issues. FIRCs bring together
instructors from all over the country, with course sizes
ranging from six to thirty participants. Throughout
the course, every instructor benefits from learning
the techniques, ideas, safety systems and operational
considerations that are brought by others. The varied
Course material focuses on new skills and knowledge. For
instance, many instructors have been asked by an aircraft
owner to teach them IFR on their private aircraft, only to
find out that the aircraft is equipped with an integrated
flight deck or “glass cockpit”. The instructor may have never
been given any guidance during initial training on how
to “teach glass”. As the National Transportation Safety
Board has stated, “single engine aircraft with glass have no
better overall safety record than traditional aircraft, but do
have a higher fatal accident rate”3. The goal of the refresher
course is to review to a certain extent, but more so to give
instructors new knowledge and skills.
The FIRC modules are led by experienced flight
instructors, pilot examiners and industry experts. For
instance, during presentations on airspace/ADS-B/RNAV,
NAV CANADA may send a controller to participate, TC
may provide a presenter to discuss the implementation of
SMS at FTUs, and so on.
Every course has its own unique set of topics and more
information is available from the course providers’ websites.
Some common topics include: instructor supervision,
operational control, flight-testing weak areas, and scenariobased training. The theme through all of the modules
is how instructors can not only improve the quality of
their work, but also the level of safety—for their students,
themselves, and for the aviation industry as a whole.
Applicable real-world content is integrated throughout, to
keep the lessons both relevant and current.
1
www.tc.gc.ca/eng/civilaviation/standards/general-personnel-statsstats-2300.htm
The topic of Human Factors, for example, may look at
the training of English as a Second Language students.
What are the statistics surrounding their safety record?
What practices have been shown to improve safety in this
environment? What instructional techniques are most
effective? Though these topics may sound daunting at
2
General Aviation Advisory Circular 421-001, June 2010
3
ASL 2/2011
Flight Operations
Flight Operations
The instructor community needs to ask the following
question: how well do we continue to develop instructors
after their initial training? In many cases, a licensed pilot
completes the instructor rating with one or two Class 1
instructors and often works at the same location once rated.
This means limited exposure for many flight instructors.
In other words, after a year or two of teaching, the rate of
acquiring new knowledge and improving instructional skill
plateaus; any gaps in knowledge or bad habits that have
developed may remain uncorrected for years.
The theme of best practices is central to the content that is
prepared for the refresher courses. Attendees have a chance
to participate in lectures, small and large group discussions
and exercises, role-playing, scenario analysis, and preparing
their own presentations. The courses are quite interactive
and not designed to be a one-way flow of information.
Pre-Flight
Pre-Flight
As the GAAC points out, “The safety of flying in
Canada depends on the competence of the pilots and
the system that supports them. The competence of pilots
depends in turn on the quality of the training system that
produces them.”2
backgrounds and experience levels of those in attendance
contribute to a sharing of knowledge, and the development
of a support network amongst instructors. Instructors
can then take what they’ve learned back to their own
Flight Training Units (FTU) to share with colleagues and
improve operations.
To the Letter
To the Letter
As of June 2010, there were over 3 000 Canadian flight
instructor ratings in force1. As with instrument ratings and
pilot proficiency checks (PPCs), the instructor rating is not
valid forever and must be renewed. The flight instructor
rating is based on a class system ranging from Class 4
to Class 1, with additional privileges granted to each
successive class as instructors gain more experience and
additional qualifications.
Guest Editorial
Guest Editorial
by Michael Schuster, Principal Consultant, Aviation Solutions
Aviation International News, April 2010
7
Guest Editorial
Flight instruction is an important part of the aviation
industry and flight instructors are professionals who should
be constantly improving their knowledge and skills. The
next time you have a renewal coming up, you may want to
consider attending one of these professional development
courses. They are one of the best ways to advance both the
quality and level of safety in Canadian flight training.
first, the courses are designed for all levels of instructors,
including Class 4. The courses are also ideal for instructors
not actively working in the field who wish to retain their
ratings, by keeping up-to-date on the latest changes, trends
and innovations in flight training.
Michael Schuster is an Airline Transport Pilot (ATP) Class 1
Instructor and authorized FIRC course provider. For more
information visit www.aviationsolutions.net/instructor.php or
email mjs@aviationsolutions.net. 4
www.tc.gc.ca/civilaviation/general/flttrain/irc/menu.htm
To the Letter
To the Letter
Instructors practicing good pre-flight briefing techniques
during a role-playing exercise.
Guest Editorial
TC has laid out comprehensive guidelines for becoming an
authorized FIRC provider. Like all other operators, their
documents and training programs are reviewed and courses
are audited. There are presently several approved course
providers running courses throughout the country.4
Pre-Flight
Pre-Flight
If not for ice, watch for mice…
Flight Operations
8
ASL 2/2011
Flight Operations
Mr. Paul Harrington of Cottam, Ontario, thought this would be of interest to ASL readers. Just after maintenance on a Cessna 172, he pushed the aircraft out to run it up, and he suddenly had a large drop on the
right magneto. He decided to check the spark plugs and ignition wires, so he pushed the aircraft back in the
hangar, took the cowls off, and found number 5 magneto wire with the top chewed in half, and other wires
with teeth marks. In 36 years of working on aircraft, Mr. Harrington said this was the first time he had ever
seen this happening. So, he wanted to share this with pilots and, aircraft maintenance engineers (AME):
if you get a magneto drop, you may want to double-check the condition of the ignition wires! He replaced
the right magneto harness; for some reason, the mice didn’t touch the left one. Be careful out there!
flight operations
Guest Editorial
COPA Corner: Practice Precautionary Approaches More Often
byFeature
Dale Nielsen. This articlePre-flight
was originally published in the “Chock to Chock” column of the July 2010 issue of COPA Flight, and is
reprinted with permission.
Most of us have never landed at a site other than an
airport and probably never will. A precautionary approach
is something we don’t practice or even think much about
because we don’t think it applies to us.
Regs & you
When we took our pilot training, we learned precautionary
approaches for use at off-airport sites. Most of us did not
have instructors who told us precautionary approaches
should be performed any time we are not certain about the
landing conditions at our point of intended landing, even
at an airport. Many of usNot
occasionally
go to unfamiliar
CivAv Med. Exam.
used
airports and some of them may have runway surface
conditions we are not certain about.
A pilot of a Cessna C-180K overflew a 2 400 foot private
strip and judged it to be firm and suitable. On landing,
the aircraft drifted right. Power was added and the aircraft
became airborne for about 100 ft and touched down
again with the right wheel on softer ground. The aircraft
continued to the right until the right wheel hit a snow drift
and the aircraft flipped over. The pilot was not injured.
A Cessna C-172 pilot departed a northern Ontario airport
for a short sightseeing flight. He returned for landing
20 minutes later and shortly after touchdown, the right
wheel hit some snow that had drifted partially across the
runway. The aircraft veered right and impacted the snow
bank on the right side of the runway. The pilot was not
injured, the aircraft was.
We should always be prepared to go around. Too often
when we expect or judge a landing site safe, we put
ourselves into the mindset that we are going to land.
We do not have reports on runway conditions at
airports without an operating control tower, flight
service station (FSS) or community aerodrome radio
station (CARS). Recent snow, rain or construction can
leave unexpected hazards. Local pilots or city crews
may clear the runways of snow. Without specific airport
training, snow windrows or clumps of hard snow can be
left at entrances to taxiways or runway intersections. Winds
may blow snow back onto runways in hard drifts. Animals
may also create runway hazards at uncontrolled airports,
with deer, coyotes, dogs and birds being the most common.
When we are not sure of surface conditions, a landing
site, airport or not, should initially be flown over at about
1 000 ft (high pass). An initial assessment can be made of
the runway surface and of the wind conditions. When the
choice of runway is made, a low pass at 300 to 400 ft can be
made along the runway and to the right of the runway to
better assess the field conditions. Three hundred to 400 ft
should safely clear all nearby obstacles and the surface
conditions can be clearly seen. This pass should be made
no slower than the flap up final approach speed. Partial flap
during this pass will lower the aircraft pitch attitude and
help with aircraft stability. The airspeed, altitude, partial flap
and trim should all be set before reaching the start of the
ASL 2/2011
9
Flight Operations
The report about the PA 24-200T accident did not say
if the pilot performed a full precautionary approach
procedure, just that he overflew the airport. Doing a full
precautionary approach procedure may have prevented
this accident.
The C‑172 pilot did not perform a precautionary approach
as he had only been gone 20 minutes. Fresh snow and
a crosswind should now be a reminder for the rest of us
that it only takes minutes for snow drifts to form across
a runway.
Pre-Flight
Pre-Flight
A pilot was intending to land his Piper PA‑24-200T
Seneca at Mont Laurier. He touched down on Runway 26
but was unable to stop the aircraft on the runway. He
eventually came to a stop in the snow, 200 ft off the end of
the runway. The runway was 100% ice covered at the time.
Fortunately no one was injured and the aircraft received
little damage.
The C‑180K pilot did
fly over the strip and
judged it suitable. It appears that just the centre portion
was suitable. He allowed the aircraft to drift to the right
away from the suitable landing area and added power to
attempt to correct, but the aircraft touched down before
the correction took effect. He should have gone around
and attempted another landing, or diverted to another
landing site.
To the Letter
To the Letter
Not used
Flight Operations
Guest Editorial
COPA Corner: Practice Precautionary Approaches More Often.................................................................................. page 9
Maint. & Cert.
Underwater Egress Testimonials Validate Process........................................................................................................... page 10
Major Accident Report : VFR into IMC Claims Seven................................................................................................ page 12
Optimistic and Ability Biases: “VFR flight into IMC won’t happen to me; but if it does I can get out of it!”............ page 17
Flt. Ops
Guest Editorial
A normal circuit pattern should be performed for the
landing whenever possible, because that is what we are used
to doing, and there are fewer chances of making errors.
Major errors to watch for when performing precautionary
approaches are: making the high pass in a dive at high
speed; not having the aircraft stabilized at an appropriate
airspeed and in an appropriate configuration for the low
pass; and abbreviating the circuit and landing hot and long.
Precautionary Approach Procedure
At any airport where you would consider a precautionary
approach prior to landing, it may be wise to perform a
Walk, if it is safe and legal to do so, or taxi the entire
runway length to check the surface. An assumption that
the rest of the runway is in the same condition as the piece
you are sitting on has resulted in more than one aircraft
getting bent.
We should not assume that conditions are safe just
because we are landing at an airport, or that a strip is safe
because someone said so. The few minutes spent doing a
precautionary approach may save us a lot of down time.
Dale Nielsen is an ex-Armed Forces pilot and aerial
photography pilot. He lives in Abbotsford, B.C., and currently
flies MEDEVACs from Victoria in a Lear 25. Nielsen is also
the author of seven flight training manuals published by Canuck
West Holdings. Dale can be contacted via e-mail:
dale@flighttrainingmanuals.com. To the Letter
To the Letter
High Pass
Low Pass
Final Approach
runway surface check prior to takeoff. Standing on the
ramp, or sitting in the aircraft on the ramp, or even on
the end of the runway will provide a good view of only a
small portion of the runway surface. There could be soft
areas, holes, rocks, pools of water, ice patches, clumps of ice
dropped from a snow plow, wind drifts of snow, animals
or birds out of your line of sight. While checking out the
runway surface, check the grass near the runway for animals
or birds.
Guest Editorial
runway so that all a pilot has to do is look to the left and
inspect the runway. If the field is judged suitable, a return
for a normal, soft or short field landing can be performed
from a normal circuit pattern.
Underwater Egress Testimonials Validate Process
Putting into words how disorientation and panic are
associated with underwater submersion in an inverted
aircraft is very difficult. Following an impact and
submersion, the sudden change to cold water and to a
dark, foreign environment can often prove overwhelming
when time is of the essence; more often than not, survival
instincts take control and people tend to panic, limiting
their ability to successfully locate the elusive door
mechanisms or other emergency exits.
Short of attending a training session in person, real life
testimonials offer wonderful educational insights on this
topic. A few years ago, I received a call from Brenda Matas,
who had been traumatized in a floatplane accident years
10
previous. I explained the program and what it could
do for her. She decided to attend one of our classes
and try to relive the experience, only this time with a
positive outcome.
Brenda had been a passenger sitting beside her husband
who was piloting their Super Bushmaster on floats. Shortly
after takeoff, the aircraft stalled and impacted the water
hard enough to blow out the front window and badly
damage the aircraft. She recounted that during the impact,
there was intense water pressure violently forcing her
backwards, and her only thoughts were not to do anything
until it all stopped. Fortunately, the aircraft remained
upright but water was rapidly flooding the cabin.
Brenda quickly undid her seat belts and assisted her
unconscious husband who had sustained minor head
injuries. Once he regained consciousness, they quickly
escaped through the side window as the aircraft inverted
and began to sink. Soon after, paddles and life vests were
collected from the debris floating freely about the downed
craft. Fortunately for Brenda and her husband, a pleasure
boat appeared shortly after the incident and the pair was
rescued and given medical assistance.
ASL 2/2011
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Flight Operations
My passion for underwater egress started—ironically—in
1977 after being initiated to a high-speed water impact
as a passenger in a Cessna 150. In spite of that incident, I
received a float endorsement the following year, went on
to a fulfilling commercial pilot career and a few years later,
in 1998, I decided to become an underwater egress and
survival skills course provider. Since then, I have observed
more than 4 000 egress students and their behaviour while
training at aquatic facilities.
Pre-Flight
Pre-Flight
by Bryan Webster, Aviation Egress Systems, Victoria, British Columbia
Guest Editorial
For Brenda, this was the end of her flying days but the
beginning of a nightmare, which began with agonizing
dreams of being trapped under water and searching in
vain for non-existent passengers, until she would wake
up shaking, sweating and crying. Two years later, once
their aircraft had been repaired, she attempted to regain
currency by flying with an experienced instructor. However,
solo flight brought back the post-crash anxiety, so Brenda
and her husband seriously considered giving up flying
altogether and selling their aircraft.
This is when Brenda heard about underwater egress
training and called me to discuss her options. After a
number of discussions, she eventually agreed to attend
the course and to face her fears. However, when Brenda
arrived at our pool facility, she was physically shaking
and had serious doubts about attending the program. We
assured her that the training was professionally supervised,
safe, and that she could start with the classroom session
and see how she felt afterwards. She agreed, and took part
in class discussions on how to handle and think about
ditching, while sharing her story with her supportive group
of classmates.
In Brenda’s words:
Bryan knew what I did not. He knew I had to go back to
that underwater experience again and that was why he
was so supportive. I finally worked up the courage to take
the course and I am very happy that I did. Huge progress
has been made from the gut wrenching apprehension at
every landing to now having the confidence that I can
think my way through an underwater egress. I now
sleep well at night and plan to take the course again in
the future.
I would recommend this type of training to everyone who
flies over water. In fact, it caused me to look at how to get
out of any submerged vehicle in a whole new way.
Sincerely, Priscilla
These two stories show how devastating aircraft accidents
can be and how they can affect people’s lives. Over the
last few years there have been many floatplane safetyrelated initiatives including new promotional campaigns,
improvements in aircraft emergency exit doors and
windows, enhanced pre-flight safety briefings by operators,
industry meetings to discuss floatplane safety, and of
course a strong push to encourage licensed personnel—and
passengers—to attend underwater egress training. This
training not only explains the perils and how to recognize
them, but it also provides the knowledge and confidence
required to escape a submerged aircraft should the
unthinkable happen.
Bryan Webster is a commercial pilot, underwater egress
and survival skills course provider, and past recipient of the
Transport Canada Aviation Safety Award. He can be reached
at info@dunkyou.com. Thank you.
ASL 2/2011
11
Flight Operations
Flight Operations
In the pool, she again showed signs of reluctance and
viewed our equipment as terrifying. Only after watching
the other students take numerous turns in the simulators
did she agree to do it. At the end of the day, Brenda was
calm and reacting in the appropriate manner, which helped
her overcome her past negative experience.
After the accident, I contacted a commercial floatplane pilot
and he suggested that I consider taking underwater egress
training. I came to your class prepared with both a strong
desire to learn how to survive a floatplane ditching plus
a strong desire to help make floatplane aviation safer. The
training was excellent and in fact was a real eye-opener.
This experience showed me how challenging it is to get out
of an inverted aircraft in the water in the best of conditions.
Pre-Flight
Pre-Flight
To the Letter
Brenda Matas with her Super Bushmaster
To the Letter
Dear Bryan,
I am a frequent floatplane passenger. I used to work on
a project that required me to travel by floatplane from
Seattle to the San Juan Islands weekly for about 5 years.
I have always been concerned with the door operation
on floatplanes. The small recessed handles are not easy
to operate, even in the best of conditions. I now live on
Saturna Island, B.C. Last fall, a floatplane went down
just south of our home and I helped friends and neighbours
search for survivors. Needless to say, this terrible accident
has affected me deeply.
Guest Editorial
A second testimonial for the underwater egress training
came from a passenger, and stemmed from a more recent
occurrence. There was a terrible floatplane accident in
the Gulf Islands near Victoria, B.C. a couple years ago. I
received a call from a person who requested underwater
egress training as she had been in the area when the mishap
took place. After the training I received a letter from her
describing the event and how it had affected her.
To the Letter
Summary
On November 16, 2008, at about 1013 Pacific Standard
Time, an amphibious Grumman G-21A departed
from the water aerodrome at the south terminal of
the Vancouver International Airport (CYVR), B.C.,
with one pilot and seven passengers for a flight
to Powell River (CYPW), B.C. Approximately
19 minutes later, the aircraft crashed in dense fog
on South Thormanby Island, about halfway between
Vancouver and Powell River. Local searchers located a
seriously injured passenger on the eastern shoreline of
the island at about 1400. The aircraft was located about
30 minutes later, on a peak near Spyglass Hill, B.C. The
pilot and the six other passengers were fatally injured, and
the aircraft was destroyed by impact and post-crash fire.
The emergency locator transmitter (ELT) was destroyed
and did not transmit.
History of the flight
The automatic terminal information service (ATIS)
issued for CYVR at 1009 reported that the wind had
decreased to 8 kts and visibility had decreased to 2 SM.
The pilot requested and received authorization from
Vancouver air traffic control (ATC) to depart under
special VFR (SVFR) via the SALMON NORTH
departure. This published VFR floatplane route requires
aircraft to be equipped with an area navigation system
such as a global positioning system (GPS) to identify
12
The first nine minutes of the flight appeared on CYVR
radar, ending about 21 NM northwest of CYVR, about
15 miles southeast of the accident site. Radar returns show
that the aircraft’s ground speed remained steady around
140 kts, normal cruise speed for this aircraft, allowing for
the 8-kt to 15-kt tailwind encountered between CYVR
and South Thormanby Island. Although there was no
intervening terrain between the radar source and the
aircraft, the radar coverage was likely limited because of
the low altitude at which the aircraft flew. Of 110 valid
radar returns, 10 returns (9 percent) showed the aircraft’s
altitude as 0 ft ASL, 96 returns (87 percent) showed the
altitude as 100 ft ASL, and 4 returns (4 percent) showed
the altitude as 200 ft ASL. No radar returns showed the
aircraft’s altitude higher than 200 ft ASL.
Approximately 12 minutes after departure, the operator
dispatch tried unsuccessfully to contact the pilot to
advise him that a special weather observation at CYPW
indicated that visibility had deteriorated to ⅜ SM in fog
and remained below VFR limits. Shortly after 1032, local
authorities learned of a probable aircraft crash in dense
fog on South Thormanby Island.
ASL 2/2011
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Flight Operations
Following the weather briefing, the pilot proceeded to
the aircraft to load the cargo and board the passengers.
During his pre-flight briefing, he advised the passengers
that the flight would be conducted at low altitude and
that if anyone was concerned, they could deplane. No one
deplaned. The aircraft was released by dispatch at 1001.
About three minutes after takeoff, approximately 2 SM
east of the SALMON VFR checkpoint, ATC approved a
right turn out of the CYVR control zone (a modification
to the published SALMON NORTH departure route).
At this point, the aircraft turned onto a track of about
308°T. A slight course change to the west was made
after which the aircraft resumed the 308°T track until
radar coverage ended. About four minutes after takeoff,
the pilot reported to CYVR tower that the visibility was
about 2 to 2 ½ SM, and that he could probably climb to
200 to 300 ft ASL. About six minutes into the flight, and
about two minutes before exiting the CYVR control zone,
the pilot reported his position as 7 ½ NM from CYVR
and noted that visibility had improved to about 4 SM. The
majority of the route was greater than 4 NM from land
or other discernable features to assist navigation. The last
communication from the pilot was at about 1021, when
he advised ATC that he was clear of the zone.
Pre-Flight
The pilot reviewed and discussed the weather with
company dispatch at 0930 and was advised to
proceed to Toba Inlet if the weather did not permit
landing at Powell River. The aviation routine weather
report (METAR) issued at 0900 for Vancouver recorded
the wind as 110°T at 10 kts and 2 ½ statute miles (SM)
visibility in mist. Cloud cover formed a ceiling at 500 ft
above ground level (AGL). The temperature was 10°C,
the dewpoint 9°C. Low ceilings and visibility along the
coast for the area of the flight route were forecast by
Environment Canada. Although the reported weather at
the Toba Inlet destination was above VFR limits, weather
at CYVR and CYPW was below VFR limits at the
scheduled departure time.
the SALMON VFR callup/checkpoint, about 6 NM
offshore. At approximately 1013, the aircraft departed
the water aerodrome westbound towards the SALMON
VFR checkpoint. The accident flight was the only fixedwing VFR departure from the water aerodrome or
CYVR before 1049 that day because other operators had
cancelled or delayed their flights due to the low visibility.
To the Letter
Pre-Flight
The following article is a condensed version of Transportation Safety Board of Canada (TSB) Final Report A08P0353,
a high‑profile accident which took seven lives. There is a universal lesson from this extensive report.
Guest Editorial
Guest Editorial
Major Accident Report: VFR into IMC Claims Seven
ASL 2/2011
13
Flight Operations
Guest Editorial
To the Letter
Pilot decision making (PDM) is critical to flight
safety. PDM can be defined as a four-step sequence:
the gathering of information, the processing of that
information, making a decision based on possible options,
and then acting on that decision. Once a decision has
been implemented, the process starts over again as
the individual now gathers information to
monitor the effectiveness of the decision.
Based on how that information is processed,
the individual then continues through the
rest of the process, and so on. Each stage in
the four-step PDM process is susceptible
to error. During the information-gathering
step, misdirected attention can cause critical
cues to go undetected. In addition, biases may
prevent a pilot from recognizing cues that are
different from those expected. The processing of
information stage will introduce errors into the
PDM process if the information is incorrect,
distorted, incomplete, or misinterpreted. The
assessment of the available options involves a
subjective risk assessment based on experience
Area map with relevant weather information locations available to the pilot
and knowledge. Pilots usually decide on the
option they perceive as most likely to result in
The wreckage was located at about 350 ft ASL on the
the best outcome given their goals. The last step in the
northeast side of an unnamed 400‑ft peak, about one
process is to implement the option that has been selected
third of a mile south-southeast of Spyglass Hill on
as the most appropriate. Errors at this step of the process
South Thormanby Island. The wreckage was examined
are typically the result of implementing an inappropriate
to the extent possible; no pre-impact mechanical failures
response or improperly carrying out the correct action.
were noted.
Pilots’ decisions can be influenced by a wide range of
The pilot was certified and qualified for the flight in
factors such as perception of the situation, experience,
accordance with existing regulations. The operator’s
training, abilities, expectations, goals and objectives,
management had met with the pilot three times to
organizational and social pressure, time-criticality
discuss concerns they had with his decision making. The
and contextual elements. A VFR pilot’s decisions are
last meeting, about three months before the accident,
largely influenced by the assessment of existing weather
was held because management was concerned that
information, the availability of additional navigational
he was completing trips in what other pilots deemed
aids, and previous experience with a route. Once a
to be adverse wind and sea conditions. The company
decision is made to depart or continue along a route,
believed that this behaviour was causing other pilots to
pilots have a tendency to continue with the selected
feel pressured to fly in those conditions and was also
course of action unless there are compelling reasons not
influencing customer expectations. At least one fishing
to do so. Additionally, pilots often seek out elements
lodge owner favoured the accident pilot because he flew
that reinforce, not contradict, the decision made (that is,
customers in and out when other company pilots would
confirmation bias). Successful experience under similar
not because they felt that the conditions were too risky.
circumstances can make pilots very reluctant to select a
different course of action. If a pilot is suddenly faced with
The day before the accident, the pilot of a float-equipped
additional unexpected cues from the environment, there
aircraft encountered a 400-ft ceiling and estimated 1 SM
is a danger that the relevant cues go unnoticed. This can
visibility near Powell River and made a precautionary
occur due to mental processing limitations as information
landing on the water to wait out the conditions. That pilot
competes for a pilot’s attention. Relevant cues can also
Pre-Flight
Pre-Flight
Decision making
To the Letter
Flight Operations
subsequently observed a Grumman Goose fly by in these
conditions. Records showed that the Grumman Goose
was piloted by the accident pilot.
Guest Editorial
At 1110, 15 minutes after the aircraft’s estimated time
of arrival (ETA) at CYPW, employees from the operator
at CYPW called their dispatch centre in Vancouver to
say that the aircraft had not arrived. The dispatchers
determined that the last recorded position was at 1025
near Sechelt, just over one third of the distance from
Vancouver to Powell River. At 1210, dispatch contacted
the Victoria Joint Rescue Coordination Centre ( JRCC)
to report the aircraft overdue. Poor visibility around the
island due to fog and cloud prevented airborne search and
rescue (SAR) efforts.
Guest Editorial
To the Letter
Transportation Safety Board (TSB) data show that
continued VFR flight into adverse weather represents
a significant threat to aviation safety. While VFRinto-instrument meteorological conditions (IMC)
accidents account for a relatively small portion (less
than 10 percent) of all reported accidents, approximately
55 percent of those VFR-into-IMC accidents were
fatal, compared to 10 percent of all other accidents. An
enormous amount of research and many studies have
been conducted to identify the causes of continued VFRinto-IMC accidents. Some of the main causes of these
accidents are as follows:
• VFR pilots can be overly optimistic on the
probability of having to fly from VFR-into-IMC,
and on their own abilities to fly out of IMC if
encountered (ability bias);
• Incorrect situational assessment can cause pilots to
prolong flight into deteriorating weather because they
do not realize that they are doing so;
• Decision framing can play a role. If pilots frame their
decisions in terms of potential losses (that is, revenue,
etc.), they are more likely to prolong flight into
deteriorating weather;
• Pilots are motivated to complete their flights; and
• Pilots may exhibit greater risk-taking behaviour as
more time and effort is invested in a flight.
Analysis
Given the conditions at takeoff and at the accident
site, as well as the forecast and reported conditions for
the en route section, it is likely that most of the flight
was conducted below the required VFR minima. The
conditions present on the day of the occurrence would
have resulted in a high likelihood that IMC conditions
would be encountered. The visibility portrayed in
the photograph as the aircraft taxied into the river at
Vancouver (see Photo 1) displays conditions below SVFR
minima for fixed-wing aircraft.
14
Photo 2. Same location as Photo 1 taken on clear day
During his pre-flight briefing, the pilot advised the
passengers that the flight would be conducted at low
altitude and that, if they were concerned, they could
deplane. This is not a normal part of the pre-flight
briefing and indicates that the pilot was aware that the
weather along the route was likely to be poor enough
that, in order to maintain ground reference, the flight
would have to be conducted at a lower altitude. However,
the special weather reports (SPECI) issued at 0925 for
Powell River showed a marginal improvement that the
pilot could have interpreted as the beginning of a trend.
This is inherently risky because a single weather report
does not confirm that a trend has commenced. Although
the large majority of weather information indicated low
cloud and poor visibility along the route, the marginal
improvement at Powell River and inaccurate information
from Merry Island may have contributed to the pilot’s
decision that weather along the route would be sufficient
for a low-level VFR flight.
The pilot’s commitment to the decision to depart
would have increased after boarding passengers, loading
baggage, and starting the engines. Once ATC approved
the pilot’s request for SVFR, the onus fell on the pilot
to ensure that weather outside of the control zone would
permit continued flight under VFR. When departing
under SVFR, VFR pilots must have an alternate plan if
below-VFR weather conditions are encountered when
they leave a control zone. The pilot did not request the
latest available weather reports (actual weather at 1000)
to determine if the weather along the planned flight
route was indeed improving. Had this been done, the
ASL 2/2011
Flight Operations
A supplementary report from the Merry Island
lighthouse indicated marginal visual meteorological
conditions (VMC). Lighthouse reports have traditionally
provided VFR pilots on the coast with a valuable resource;
however, in this case, the report was inaccurate. This may
have contributed to the pilot’s conclusion that weather
along the route was acceptable.
Photo 1. Aircraft entering river for takeoff (accident flight.)
Photo courtesy of Mr. Rich Malone, who captured
it with his cell phone.
Pre-Flight
Pre-Flight
VFR-into-instrument meteorological
conditions accidents
To the Letter
Flight Operations
Guest Editorial
be missed by a pilot if they are deemed less important
than others, leading a pilot to focus on cues that may
erroneously support the pilot’s preferred course of action.
In this occurrence, the pilot’s safety significant decisions
were the decision to take off and the decision to continue
the flight into adverse weather conditions.
ASL 2/2011
15
Flight Operations
Guest Editorial
To the Letter
Once airborne, the options available to the
pilot were to continue on the planned route,
alter the route, return to CYVR, divert to
another aerodrome, or land on the water.
All these options involved risks. Since he
had been navigating from SALMON using
Wreckage of the Grumman Goose being examined by an accident investigator
GPS, he likely relied heavily on the GPS for
from the Transportation Safety Board of Canada.
navigation in the absence of adequate visual
cues. As he approached Thormanby Island, it
Damage to the aircraft and to the trees at the accident site
is highly likely that the pilot expected that he
indicated the aircraft’s speed and attitude immediately
would regain adequate visual reference with the ground.
before impact. The long, straight, rising angle of the
However, it is difficult to accurately assess visibility over
swath cut through the trees and the extreme damage to
a featureless water surface, and it likely was not apparent
those trees and to the aircraft indicate that the aircraft
to the pilot that the visibility had become so poor that
was flying at relatively high speed and climbing rapidly
a change of plan was required. When the pilot finally
before collision with terrain. Extreme damage to all the
sighted Thormanby Island, the aircraft was too close for
propeller blades indicates that high engine power was
the pilot to be able to avoid colliding with terrain.
being developed. This combination indicates that the
pilot reacted to sighting terrain seconds before impact
Several of the factors that influence a pilot’s decision
and pulled the aircraft up into a rapid climb. However,
to continue flight from VFR into IMC existed in this
the pull-up was initiated too late to out-climb the rising
accident: previous successes in low visibility, difficulty in
terrain that lay ahead.
assessing actual visibility, commitment to a chosen course
of action, the consequences of changing the chosen course
The accident aircraft’s flight at high speed while at low
of action, and ability bias.
altitude and in low visibility entailed significant risks.
These include: decreasing the available time to plan and
It is likely that one or more of these factors were
react to an emergency, limiting the available options in
contributory to this accident.
the event of an emergency, increasing the likelihood of
inadvertent descent into water or ground — particularly
CFIT
during a manoeuvre such as turning around — and
The accident flight was conducted in meteorological
increasing the likelihood of collision with ground-based
conditions below VFR minima. There is no indication
obstacles and birds.
that the pilot attempted to land on the water, or to
turn around, in the face of extremely low visibility and
Findings as to causes and contributing factors
ceilings. It is highly likely that the pilot was relying
1. The pilot likely departed and continued flight in
on the GPS for navigation and that, as he approached
conditions that were below VFR weather minima.
Thormanby Island, his attention shifted from the GPS
to looking outside the aircraft. While flying in fog, a
2. The pilot continued his VFR flight into IMC, and did
controlled flight into terrain (CFIT) occurred during
not recognize his proximity to terrain until seconds
an attempt to avoid terrain. No evidence was found to
before colliding with Thormanby Island, B.C.
indicate that the aircraft was out of control before impact.
Pre-Flight
Pre-Flight
There are indications that the accident
pilot had a tendency to push the weather.
For instance, the day prior, the pilot was
flying in below-VFR conditions. The pilot’s
decision to depart was likely affected
by confidence gained through previous
successes under similar conditions.
To the Letter
Flight Operations
Guest Editorial
deteriorating weather in Powell River
would have given the pilot the opportunity
to reconsider his decision to depart. When
the aircraft departed, the visibility on the
river was little more than ½ SM.
Guest Editorial
Findings as to risk
1. The reliance on a single VHF-AM radio for
commercial operations, particularly in congested
airspace, increases the risk that important information
is not received.
3. The lack of PDM training for VFR air taxi operators
exposes pilots and passengers to increased risk when
faced with adverse weather conditions.
4. Some operators and pilots intentionally skirt VFR
weather minima, which increases risk to passengers
and pilots travelling on air taxi aircraft in adverse
weather conditions.
5. Customers who apply pressure to complete flights
despite adverse weather can negatively influence pilot
and operator decisions.
7. Transport Canada’s (TC) guidance on risk assessment
does not address incremental growth for air operators.
As a result, there is increased risk that operators will
not conduct the appropriate risk analysis as their
operation grows.
9. There were no company procedures or decision
aids (that is, decision tree, second pilot input,
dispatcher co-authority) in place to augment a
pilot’s decision to depart.
10. Because the aircraft’s ELT failed to operate after the
crash, determining that a crash had occurred and
locating the aircraft were delayed.
Operator
Immediately following the accident, the operator
suspended air taxi operations and implemented several
actions to reduce risk before resuming operations. Since
then, the company has implemented several other
voluntary safety actions that exceed TC’s requirements
for VFR air taxi operations. These additional safety
actions include:
• Raising the minimum departure visibility from the
TC-regulated 2 SM to a company limit of 3 SM from
a base of operations for VFR aircraft.
•
Providing a PDM course, including how GPS affects
decision making, to all the VFR floatplane pilots
and adding PDM training to the company VFR
training syllabus.
•
Implementing a dispatch procedure that gives the
dispatcher/flight-follower co-authority over the
release of the aircraft.
•
Conducting risk assessments of VFR routes and
operations (including reviewing weather, wind,
and water condition limitations) and developing a
destination-specific risk rating system.
•
Conducting line checks at least three times a year on
each VFR pilot.
•
Regularly monitoring the stored data of the GPS
carried on the aircraft to ensure that pilots are
flying within company and Canadian Aviation
Regulations (CARs) limits.
•
Installing aviation-specific satellite tracking systems
in all VFR aircraft to replace the satellite messengers
previously installed in those aircraft and eliminate the
need to monitor GPS data.
•
Conducting annual company culture surveys to
identify areas needing improvement.
•
Providing accident investigation training for key
company personnel.
•
Revising the company’s SMS manual to include
revised risk assessment procedures and accident
investigation training.
11. On a number of flights, pilots on the
Vancouver‑Toba Inlet route, B.C., departed over
16
ASL 2/2011
Flight Operations
Flight Operations
8. Previous discussions between the operator and the
pilot about his weather decision making were not
documented under the company’s safety management
system (SMS). If hazards are not documented, a
formal risk analysis may not be prompted to define
and mitigate the risk.
Safety action taken
Pre-Flight
Pre-Flight
6. Incremental growth in the operator’s support to the
client did not trigger further risk analysis by either
company. As a result, pilots and passengers were
exposed to increased risks that went undetected.
12. The over-reliance on GPS in conditions of low
visibility and ceilings presents a significant safety risk
to pilots and passengers.
To the Letter
To the Letter
2. Flights conducted at low altitude greatly decrease
VHF radio reception range, making it difficult
to obtain route-related information that could
affect safety.
maximum gross weight due to incorrectly calculated
weight and balances. Risks to pilots and passengers
are increased when the aircraft is operating outside
approved limits.
Guest Editorial
3. The indication of a marginal weather improvement at
Powell River, B.C., and incorrect information from
Merry Island, B.C., may have contributed to the
pilot’s conclusion that weather along the route would
be sufficient for a low-level flight.
Transport Canada
In December 2009, as a follow-up to the Safety Study
on Risk Profiling the Air Taxi Sector in Canada, TC made
available on its Web site the Pilot Decision Making
Simulator, developed by inspector Gerry Binnema (now
retired from TC). This unique tool allows pilots to
practice aviation-related decision making in a low-risk
environment. The simulator can be found on TC’s website
at www.tc.gc.ca/eng/civilaviation/regserv/safetyintelligenceairtaxistudy-simulation-menu-1829.htm.
Transportation Safety Board of Canada
On the day this report was publicly released, the TSB
issued a communique to the aviation community warning
that flying in low visibility is causing too many deaths in
Canada. TSB’s Bill Yearwood said, “There are some hard
lessons that need to be learned and re-learned in aviation
and this is one of them.”
Yearwood went on to say, “VFR pilots must be able to
see the ground below and ahead of them at all times. It’s
almost impossible to avoid obstacles and rising ground
when clouds are low, the visibility is poor and you’re flying
at twice the speed of cars on the highway.”
Aircraft colliding with land or water under crew control
are among the deadliest accidents in aviation. They
account for 5 percent of accidents but 25 percent of
fatalities in Canada. The risk is even greater when aircraft
venture into mountainous terrain in poor weather. That
is why Collisions with Land and Water is one of the
nine critical safety issues on the TSB’s highly publicized
safety Watchlist.
“Competition is strong and customers can put pressure
on companies to complete flights”, says Yearwood. “We
need to see better decisions from companies and pilots to
prevent these kinds of accidents.”
To read the complete final report A08P0353 on this
occurrence, visit the TSB Web site at www.tsb.gc.ca. To the Letter
To the Letter
Having pilots and dispatchers document
circumstances where poor weather affects a flight
and using those data for track monitoring and to
determine risk exposure over an extended period.
Guest Editorial
Guest Editorial
•
Optimistic and Ability Biases: “VFR flight into IMC won’t happen to me; but if it does I can get
out of it!”
by Dale Wilson, Professor, Aviation Department, Central Washington University
Flight Operations
related health problems than other smokers; in drivers
who believe they are less likely than other drivers to
be involved in an automobile accident; and, in general
aviation (GA) pilots who believe they are less likely than
other pilots to experience an aircraft accident.
Most people also believe they are superior to others when
it comes to their own skills and abilities. For example, a
high majority of managers rate their managerial skills as
higher than those of their respective peers; U.S. college
professors think they do above average work compared
to other professors; Americans believe they are more
intelligent than their fellow citizens; and, automobile
drivers believe they are better, and are less likely to take
risks, than their fellow drivers. Unfortunately, this above
average effect, or ability bias, also seems to be evident in
pilots; studies confirm that most pilots think they are
safer, are less likely to take risks in flight, and possess
greater flying skill than their peers.
We administered a questionnaire to 160 pilots asking
them to compare themselves to other VFR pilots with
similar flight background and experience as their own
ASL 2/2011
17
Flight Operations
Do you think you’re less likely than other pilots to
experience a VFR-flight-into-instrument meteorological
condition (IMC) accident? Do you think you’re better
at avoiding VFR flight into IMC or successfully flying
out of IMC should you inadvertently encounter such
conditions? These are questions my colleague and I
sought to answer as we reflected on the preponderance
of scientific evidence indicating that most people are
unrealistically optimistic and are overconfident in their
abilities. For example, when university students were
asked to rate the likelihood of owning their own home,
obtaining a good job after graduation, or living a long
life, almost all of them believed they had a greater chance
than their classmates; when asked to rate their odds of
developing a drinking problem, getting divorced soon
after marriage, or being fired from a job, almost all of them
believed they had a lower chance than their classmates.
Since it’s impossible for the majority of people in a given
group to have a greater (or lesser) chance of experiencing
a positive (or negative) event than the median of the
group, some kind of optimistic bias must be at work. This
bias is seen in the high majority of cigarette smokers
who believe they are at less risk of developing smoking-
Pre-Flight
Pre-Flight
The following article is based on research published by the author and his colleague in a paper presented at the 11th International
Symposium on Aviation Psychology, in Columbus, Ohio. It serves as an addendum to the preceding story, which touched on
biases, particularly the ability bias.
Guest Editorial
To the Letter
Dale Wilson teaches aviation safety and human factors courses
at Central Washington University in Ellensburg, WA. He
has written several articles on night flying, visual illusions,
and VFR flight into IMC. Links to his work, including the
original research paper this article is based on—“Optimistic
and Ability Biases in Pilots’ Decisions and Perceptions of
Risk Regarding VFR Flight Into IMC”—can be found at
www.cwu.edu/~aviation/faculty_wilson.html. Flight Operations
Flight Operations
Pre-Flight
Pre-Flight
In spite of a gradual decline in the percentage of weatherrelated accidents, VFR-into-IMC is still the leading cause
of fatal GA weather-related accidents and continues
The optimistic and ability biases are only two of several
complex and often unconscious factors that contribute to
what the aviation safety community has historically cited
as the major cause of these accidents: get-home-itis. Added
to this malady is the strong influence other people can
have on pilot decision making: compared to other aircraft
accidents, a recent study found a significantly higher
percentage of VFR-into-IMC accident flights carry
passengers on board. Therefore, to protect yourself from
the VFR-into-IMC trap, it is vital that you recognize that
your decision making is not always rational, and if left
unchecked, the biases we all appear to be vulnerable to
could prod you into going somewhere you shouldn’t.
To the Letter
Clearly, all of us can’t be above average, nor do all of
us have a lower-than-average chance of experiencing
an aircraft accident, yet that is what most of us believe.
Why is that? These biases are part of a family of what are
known as self-serving biases that serve to protect our ego
by painting an unrealistic positive view of ourselves. In
fact, the strength of these biases is significantly reduced
in mildly depressed people and for those with lower
self-esteem; compared to so-called mentally healthy
individuals (presumably most pilots), studies indicate that
these people actually exhibit more accurate and realistic
perceptions of reality! There is also considerable evidence
supporting a link between a positive, optimistic approach
to life and reduced susceptibility to physical illnesses. The
troubling irony is that even though these biases seem to
be good for our overall physical and mental health, they
can also lead to unsafe behavior.
to be a leading cause of all fatal aviation accidents in
Canada and the United States. Even though a variety
of environmental factors such as mountainous terrain
and darkness play a role, investigators consistently cite
limitations in planning, judgment, and decision making
as reasons pilots initiate or continue VFR flight into
unsuitable weather.
Guest Editorial
when rating themselves for the following: their chances
of experiencing an accident due to inadvertent flight
into IMC; their ability to avoid inadvertent flight into
IMC; and, their ability to successfully fly out of IMC. The
results were unequivocal: participants believed they were
less likely than others to experience a VFR-into-IMC
accident and believed they were better than average at
avoiding inadvertent flight into IMC and successfully
flying out of IMC.
18
ASL 2/2011
Accident Synopses
Repair and Modification of Amateur-built Aircraft
by Maurice Simoneau, Civil Aviation Safety Inspector, Aircraft Maintenance and Manufacturing, Standards, Civil Aviation,
Pre-flight
Transport Canada
(1) Except as provided in subsection (5) and in the
case of aircraft that are operated under a special
certificate of airworthiness in the owner-maintenance
classification, a person who signs a maintenance
release in respect of a major repair or major
modification on an aeronautical product shall ensure
that the major repair or major modification conforms
to the requirements of the relevant technical data
Recreational aviation
Owners of recreational aircraft, including amateurbuilt aircraft, sometimes have the impression that
their recreational aviation activities take place outside
the
mainstream of civil aviation, and therefore that
Regs & you
certain requirements of the Canadian Aviation
Regulations (CARs) do not apply, or have little
application, to their aircraft.
In recent years, the regulatory burden applicable to
recreational aviation has been made somewhat lighter
and
clarifications have been made where necessary. For
Not used
example, with aircraft operating under a special certificate
of airworthiness in the amateur-built classification,
entries regarding the technical records for the airframe,
engine and propeller may be kept in the journey
log (see CAR 605.92(3)). In the case of airworthiness
directives, a clarification was made about exemption from
requirements for owners of aircraft in the amateur-built or
owner-maintenance classification (see CAR 605.84(1)(b)).
Despite the above, unless the CARs say otherwise,
amateur-built aircraft are subject to the same maintenance
requirements as aircraft for which the Minister has issued
a type certificate.
Maintenance
All maintenance tasks and all elementary work
(see Appendix A of CAR standard 625) must be entered
in the aircraft’s technical record. Aside from elementary
work, a maintenance release for all maintenance tasks
performed (see CAR 571.10) can be signed by the
owner of the aircraft or by an aircraft maintenance
engineer (AME) (see CAR 571.11).
(a) that have been approved or the use of which
has been approved within the meaning of the
term “approved data” in section 571.06 of the
Airworthiness Manual; or
(b) that have been established within the meaning of
the term “specified data” in section 571.06 of the
Airworthiness Manual.
(2) Except as provided in subsection (5), a person
who signs a maintenance release in respect of a
repair or modification, other than a major repair
or major modification, shall ensure that the repair
or modification conforms to the requirements of
the relevant technical data within the meaning of
the term “acceptable data” in section 571.06 of the
Airworthiness Manual.
Admittedly, CAR 571.06 is difficult to understand, and
the somewhat convoluted wording does not help. To make
it easier to understand, here is a simplified version of these
two paragraphs:
CAR 571.06
The first two paragraphs of CAR 571.06 address repairs
and modifications. They stipulate the following:
ASL 2/2011
19
Regulations and You
This rule also applies to repairs and modifications
to amateur-built aircraft, the subject of this article.
CAR 571.06 describes the conditions applicable to
repairs and modifications to an amateur-built aircraft.
Paragraphs 571.06(1) and (2) are of the greatest interest
in this case.
a) all repairs and modifications must be performed
in accordance with acceptable technical data,
within the meaning of the term “acceptable data”
in section 571.06 of the Airworthiness Manual;
b) all major repairs and major modifications on
an aircraft for which a type certificate has been
issued or accepted by the Minister for the
purposes of issuing a certificate of airworthiness
must be performed in accordance with either
“approved” technical data, within the meaning
of the term “approved data” in section 571.06
of the Airworthiness Manual, or “specified”
technical data, within the meaning of the
term “specified data” in section 571.06 of the
Airworthiness Manual;
Recently Released TSB Reports
Recently Released TSB Reports
Repair and Modification of Amateur-built Aircraft ...................................................................................................... page 19
Fatigue Risk Management System for the Canadian Aviation Industry: Introduction to
Fatigue Audit Tools (TP 14577E)........................................................................................................................... page 21
Maint. & Cert.
Accident Synopses
Regulations and You
maintenance and certification
Maintenance and Certification
Maintenance and Certification
TSB reports
Maintenance and Certification
Recently Released TSB Reports
The general rule, as stated in a) – “all repairs and
modifications must be performed in accordance with
acceptable technical data, within the meaning of the term
“acceptable data” in section 571.06 of the Airworthiness
Manual” – is applicable to all aircraft, whether certified
or not, whether used under a certificate of airworthiness
or a special certificate of airworthiness, and whether used
for commercial or recreational purposes. The same rule
applies to all aircraft, including amateur-built aircraft.
The general rule specifies that technical data must
be “acceptable” in order to perform any repair or
modification. The data include:
However, it is possible that AC 43.13‑1B and 43.13‑2B
do not have the answer for a particular repair or
modification required. In such cases, aircraft owners
could either develop their own data for a repair or
modification, or they could show that their data complies
with standards recognized in the aviation community or
with generally accepted practices. This technical data does
not need to be approved by Transport Canada. The owner
must ensure that the data is appropriate to the repair or
modification in question. It’s a matter of common sense!
The general rule that all repairs and modifications must be
performed in accordance with “acceptable” technical data
is the only rule that applies to amateur-built aircraft (and
to aircraft in the owner-maintenance classification), which
greatly simplifies things for the owner. However, it must
not be forgotten that a modification may have an impact
on structural strength, performance, operation of the
power unit, or flight characteristics. A modification must
not be taken lightly. It is important to think before acting.
20
ASL 2/2011
Regulations and You
a) drawings and methods recommended by the
manufacturer of the aircraft, component, or
appliance (manufacturer’s maintenance manual,
Technical records
structural repair manual, overhaul manual, service
Details of the repair or modification must be entered in
bulletins, technical instructions);
the journey log or in the technical record, and must be
b) Transport Canada advisory documents; and
accompanied by the maintenance release. It is important
c) advisory documents issued by foreign
to enter data references; without them, the data has little
airworthiness authorities with whom Canada
value. For example, the entry might read:
has entered into airworthiness agreements or
understandings such as current issues of
NOT GREATER THAN "A"
I TUBE CIRCUM.
4
Advisory Circular (AC) 43.13-1 and -2
(MAX.)
2A
2A
issued by the U.S. Federal Aviation
Administration (FAA), Civil Aviation
A
Information Publications issued by the
Civil Aviation Authority (CAA) of the
United Kingdom, or Advisory Circulars DAMAGE
Joint (ACJs) issued by the Joint Aviation
FIGURE 4-36. Welded patch repair.
Authority ( JAA), or Acceptable Means
of Compliance issued by the European
Lower right fuselage spar, 20 inches from the
Aviation Safety Agency (EASA).
leading edge of the horizontal stabilizer: repaired
by adding doubler, oxy-acetylene weld, repainted.
FAA Advisory Circulars 43.13‑1B and 43.13‑2B are
Reference: AC 43.13-1B, chapter 4, section 5,
recognized as the references for all amateur-built aircraft
paragraph 4.94 and figure 4-36.
Recently Released TSB Reports
Regulations and You
General rule
Methods and drawings set out in airworthiness
directives may also serve as acceptable data for repairs or
modifications. While amateur-built aircraft owners do not
have to comply with airworthiness directives, it is highly
recommended that they review applicable directives in
order to decide whether to comply on a voluntary basis
for the purpose of improving the safety of their aircraft.
Accident Synopses
Accident Synopses
The above version makes it clear that only the general rule
in a) applies to amateur-built aircraft. Versions b) and c)
above are exceptions to the rule; b) is an exception to a),
and c) is an exception to b).
owners and manufacturers. Whether for repairing fabric
coverings, refurbishing tubular members, replacing a
wooden part or installing a doubler, AC 43.13 is the go-to
source of information.
Maintenance and Certification
c) aircraft for which a special certificate of
airworthiness in the owner-maintenance
classification has been issued are exempt from
the requirement to perform major repairs and
major modifications in accordance with “approved
data” or “specified data”, within the meaning of
the terms “approved data” and “specified data”
in section 571.06 of the Airworthiness Manual;
major repairs and major modifications may be
performed in accordance with “acceptable data”,
i.e. acceptable to the Minister.
Maintenance and Certification
[signed] Ty Wright
Conclusion
Every repair or modification must be performed in
accordance with acceptable technical data. This data may
include analyses, calculations, references, drawings, or
sketches. Every repair or modification must be entered
in the appropriate technical record and there must be a
maintenance release for it.
date
Maintenance release
After a repair or modification, owners must not forget
the maintenance release, which includes the following
statement or similar: “The described maintenance has
been performed in accordance with the applicable
airworthiness requirements.”
If a job needs to be done, it should be done well.
Maintenance and Certification
The described maintenance has been performed
in accordance with the applicable airworthiness
requirements.
As the owner of an amateur-built aircraft, don’t you
deserve a job well done? This is the sixth of a seven-part series highlighting the work of the Fatigue Risk Management System (FRMS) Working Group
and the various components of the FRMS toolbox. This article briefly introduces TP 14577E—Introduction to Fatigue Audit
Tools. Intended for managers, this document provides an overview of tools available to help determine whether scheduling
provides employees with adequate opportunities to get sufficient sleep. The complete FRMS toolbox can be found at
www.tc.gc.ca/eng/civilaviation/standards/sms-frms-menu-634.htm. —Ed.
Introduction
The purpose of this guide is to provide an overview of
various tools and techniques to ensure that work schedules
meet the requirements of a Fatigue Risk Management
System (FRMS). An effective FRMS consists of several
levels of fatigue hazard controls (see Developing
and Implementing a Fatigue Risk Management
System (TP 14575E) for a detailed discussion). One of the
first things that companies need to examine is whether the
schedule provides employees with an adequate opportunity
to get enough sleep to be fit for work (Level 1 control).
Accident Synopses
Accident Synopses
Fatigue Risk Management System for the Canadian Aviation Industry:
Introduction to Fatigue Audit Tools (TP 14577E)
Regulations and You
Error Trajectory
Control Mechanism
Prescriptive CARs
requirements
Fatigue modelling
Sleep opportunity
1
Sleep obtained
2
Prior sleep/wake data
3
Symptom checklists
Self-reporting
behavioural scales
Physiological monitoring
Fatigue-related errors
4
Fatigue-proofing strategies
SMS error analysis system
Fatigue-related incidents
5
SMS incident analysis system
Fatigue-related
symptoms
ASL 2/2011
Regulations and You
Active Errors
Latent Errors
Hazard Assessment
Recently Released TSB Reports
Recently Released TSB Reports
Hazard-Control Model for Fatigue Risk Management
21
Designing a work schedule
In the past, hours-of-service (HOS) rules have been
used to ensure that a schedule provides adequate sleep
opportunity between shifts and does not result in significant work-related fatigue. In principle, this appears
to be a reasonable strategy. However, HOS regulations
designed to be applied generically to an entire industry can
be inflexible and ineffective for an individual organization.
They may not guarantee sufficient sleep opportunity.
In designing an FRMS, it is important to understand that
there is no such thing as a perfect schedule. Work schedules
need to be structured around competing needs, such as
operational safety and employee family and social life. For
example, the “family friendliness” of a work schedule is
likely to be determined by how much time off it provides
during times of high social value (i.e., afternoons,
evenings, and weekends). The “sleep friendliness” of a
work schedule depends on the breaks it provides during
times of high sleep value (i.e., nights between 9 p.m. and
9 a.m.). While sleep should be the primary concern, other
factors such as the family and social life of employees
should be considered, because they can have a direct effect
on whether employees are able to use the time off to sleep.
Consulting with employees during the early stages of
implementing an FRMS can help find a balance between
these competing needs.
Providing adequate sleep opportunity
To determine whether a given schedule may result in
work-related fatigue, calculate the sleep opportunity that it
provides. There are various ways to do this. This document
outlines two methods of managing sleep opportunity:
•
Automated fatigue audit systems. Biomathematical
modelling software has been developed that can
predict how much sleep an employee is likely to get
in a given schedule. The software is able to calculate
a fatigue likelihood score for each employee at any
given point in the schedule.
•
Manual fatigue audit systems. For organizations with
relatively simple schedules or that may not want
to invest in software, manual calculations can also
be performed to generate scores that provide an
indication of fatigue likelihood.
We conclude this introduction to TP 14577E by encouraging
our readers to view the entire document at
www.tc.gc.ca/media/documents/ca-standards/FRMS_14577eng.pdf. TC AIM Snapshot: Shuttle Procedure
A shuttle procedure is defined as a manœuvre involving a descent or climb in a pattern resembling a holding
pattern. Shuttles are generally prescribed on instrument procedures located in mountainous areas. In the
approach phase, it is normally prescribed where a descent of more than 2 000 feet is required during the
initial or intermediate approach segments. It can also be required when flying a missed approach or departure
procedure from certain airports. A shuttle procedure shall be executed in the pattern as published unless
instructions contained in an ATC clearance direct otherwise.
To ensure that the aircraft does not exceed the obstacle clearance protected airspace during a shuttle descent or
climb, the aircraft must not exceed 200 KTIAS while in the shuttle descent or climb, nor exceed one minute
outbound still air time. Normal aircraft speed may be flown once the aircraft leaves the shuttle pattern.
(Ref: Transport Canada Aeronautical Information Manual (TC AIM), Section RAC 10.9)
22
ASL 2/2011
Maintenance and Certification
summaries are extracted from Final Reports issued by the Transportation Safety Board of Canada (TSB). They have
been de-identified and include the TSB’s synopsis and selected findings. Some excerpts from the analysis section may be included,
where needed, to better understand the findings. For more information, contact the TSB or visit their Web site at
www.tsb.gc.ca. —Ed.
TSB
Final Report A07W0003—Loss of Control—
Maint. & Cert.
Marginal Weather
The calculated aircraft weight at impact was just below the
maximum gross weight; however, the amount of additional
weight of the airframe ice was not quantified. The centre
of gravity (CG) was at or slightly aft of the aft limit. This
configuration would not have created a problem under
normal flight conditions, but the aft CG would have
increased the difficulty in recovering from a stall.
Under the operator’s Transport Canada exemption for
operations below 1 000 ft AGL with less than two miles
of flight visibility, the pilot had to be trained in the use of
a global positioning system (GPS) receiver. There is no
record of his having received the required instruction. The
coordinates entered for the lodge were about a mile east
of the lodge, and the pilot had turned northeast (away
from the lodge) before reaching this waypoint. There is a
probability that the pilot abandoned the use of the GPS
when he reached the north shore of the lake, and turned
left to follow the shore of the lake for navigation, since
his visual reference was out his left side window with his
windshield obscured by ice. His subsequent flight path
continued to track eastward away from the GPS waypoint
and away from the lodge, until the aircraft crashed.
Recently Released TSB Reports
Recently Released TSB Reports
On January 3, 2007, a Cessna A185F departed
Yellowknife, N.W.T., at 1019 Mountain Standard
Time (MST), with a pilot and three passengers on
Pre-flight
board,
for a round trip flight to Blatchford Lake Lodge,
approximately 53 NM southeast. The aircraft was on
a company flight itinerary with an estimated time of
arrival of 1100. When there was no contact from the pilot
by 1300, a communication search and track crawl was
conducted by company aircraft, but this was unsuccessful
in Regs
locating
& you the aircraft. No emergency locator transmitter
signal was detected at any time. At 1513, the company
reported the aircraft overdue to the flight service station.
An active search by the rescue coordination centre was
conducted using a number of aircraft. The wreckage of
the aircraft was found at 1215, January 4, 2007, on the
ice at Blatchford Lake. The pilot and two passengers had
sustained
Not used fatal injuries, one passenger had sustained serious
injuries, and the aircraft was substantially damaged.
the effect of the ice on the wings. The use of flaps would
have decreased his stall speed, but the flaps had not been
deployed. The stall warning had not activated to warn of
the impending stall.
Accident Synopses
Accident Synopses
Recently released
The
following
TSB reports
Maintenance and Certification
recently released tsb reports
It was determined that the aircraft stalled while in a left
turn at low level. With the forward visibility through the
windshield obscured by ice, the pilot was most likely flying
with attitude references through his left side window. In a
left turn, the descending left wing would have obstructed
his visibility, leaving only a view of the snow-covered lake
surface below. The conditions would have been conducive
to a whiteout situation, whereby the snow-covered lake
surface would blend with a snowy, obscured ceiling to
disorient the pilot by eliminating all horizon references.
The pilot’s manoeuvring speed was unknown, but entering
a turn would have increased the stall speed, as would
Regulations and You
Regulations and You
Analysis
Map of area
The pilot was required to have had a minimum of
500 hours in operations under Section 700 of the CARs
or equivalent to qualify for low-level/limited visibility
flight. He had about 16 hours commercial (Section 700
of the CARs) flying time with about 1500 hours of non-
ASL 2/2011
23
Maintenance and Certification
Accident Synopses
Recently Released TSB Reports
Other finding
1. The pilot had not been trained in the use of the GPS
as required by regulation for low-level flight/limited
visibility flight.
TSB Final Report A07W0099—Load Shift/Loss
of Control on Takeoff
On June 2, 2007, a de Havilland DHC-3T Turbo Otter
had been loaded with a cargo of lumber at Mayo, Y.T.
The aircraft was taxied to the threshold of Runway 06 and
the pilot began the take-off roll at 1755 Pacific Daylight
Time (PDT). At liftoff, the aircraft entered an extreme
nose-up attitude and began to rotate to the right. Shortly
thereafter, the aircraft struck the airport ramp. The pilot,
who was the sole occupant of the aircraft, was fatally
injured. A small post-impact fire was extinguished by first
responders.
Search and rescue (SAR) efforts were delayed for several
hours because the emergency locator transmitter (ELT)
did not function. The unit was capable of operating, but the
impact activation switch (G switch) was oriented to sense a
forward impact, not a vertical (downward) impact.
Findings as to causes and contributing factors
1. The aircraft stalled at an altitude too low for the pilot
to recover.
2. The aircraft’s stall speed and stall recovery
characteristics were affected by the left turn, airframe
icing, and the aft centre of gravity loading.
Regulations and You
3. The pilot’s visibility was compromised by the marginal
weather conditions and an ice-covered windshield,
with a probability that the pilot had entered whiteout conditions.
The aircraft was loaded with a mixture of rough and
finished lumber weighing approximately 2 213 lbs. The
cargo was composed of six 16‑ft rough beams measuring
7 ½ in. by 7 ½ in., a selection of 16‑ft rough lumber, and a
selection of 10‑, 12‑ and 14‑ft finished boards. The lumber
was loaded so that all the boards were flush with the front
of the cabin. At rest, the aircraft described a 9 degree
nose-up attitude, resulting in the cargo being loaded in
an “uphill” manner while the aircraft was on the ground
(see figure 1). Before the occurrence flight, several loads of
lumber had been hauled to the same destination.
Findings as to risk
1. The pilot self-dispatched on a flight that was not
in accordance with the requirements outlined in
the company operations manual. He continued the
flight after encountering conditions beyond his
capabilities in regards to training, equipment, and
operating conditions.
24
9°
Figure 1: de Havilland DHC-3T Turbo Otter
ASL 2/2011
Recently Released TSB Reports
Regulations and You
The cargo and baggage was not secured, nor was there any
means on board for securing the baggage and cargo to the
tie-down rings. Because the primary impact was oriented
vertically, the unsecured items probably did not project
into the cabin and passengers. It could not be determined
whether the baggage carried in the passengers’ laps
contributed to the severity of their injuries. The survivor
was the passenger without baggage in his lap.
3. Two of the passengers were carrying unsecured
baggage in their laps.
Accident Synopses
The company operations manual specified that the
Cessna 185 will not depart into forecast icing conditions.
Freezing fog and patchy moderate mixed icing was forecast
for the destination area when the aircraft departed, and
the pilot report from 0651 reported rime ice upon entering
clouds at 1 100 ft ASL. After departure, the pilot had
initially climbed to 1 400 ft ASL, then began a continuous
descent to about 1 000 ft ASL near his destination. He had
encountered icing conditions as forecast and reported, as
evidenced by the ice remaining on the airframe after the
occurrence. The aircraft was not equipped or approved to
operate in icing conditions.
2. The baggage and cargo were not secured, and there
were no means on board for securing the baggage and
cargo to the tie-down rings.
Maintenance and Certification
commercial single-engine flying time. He had completed
his low-level flying training, but did not adhere to the
operations manual requirements that specified that
the aircraft was to be operated at 80 knots indicated
airspeed (KIAS) with 10° of flap. The aircraft airspeeds
varied from 130 KIAS to 77 KIAS, and flaps were
not deployed.
Maintenance and Certification
Accident Synopses
On August 12, 2007, a Bell 206B Jet Ranger helicopter
was over Abraham Lake, Alta., on final approach to
the Cline River heliport (CCR5), at approximately
1420 Mountain Daylight Time (MDT) when the
engine (Rolls-Royce/Allison 250-C20B) decelerated
and flamed out. The pilot entered autorotation and the
helicopter descended into the lake, rolled onto the right
side, and sank close to shore. The pilot and the passenger
in the left cabin seat evacuated the wreckage without
assistance. The passenger in the right cabin seat required
the pilot’s assistance to release the lap belt and exit the
wreckage after the cabin became submerged. All three
occupants sustained minor injuries. The helicopter was
substantially damaged and there was no post-impact fire.
Accident Synopses
There are several documented accidents in the TSB
database where the cargo has shifted and resulted in loss of
control accidents.
• A85Q0057 – Two fatalities. A float-equipped Cessna
305C stalled with an aft CG and unsecured load.
• A00C0059 – Two fatalities. A DC-3 lost control
during a go-around procedure. The aircraft
had CG aft of the rear limit, and the cargo was
inadequately secured.
• A01W0239 – Three fatalities. A Beech UC45-J lost
control after takeoff with an inadequately secured load
of moose meat.
• A06P0095 – One serious injury. A Cessna 185B aft
CG aggravated by a possible load shift in turbulent
conditions led to a loss of control.
TSB Final Report A07W0150—Power Loss
Maintenance and Certification
The load was secured with a single one-inch cargo strap
that was placed over the lumber. The strap was fastened to
tie-down points located ahead of the rear cargo doors. The
floor of the aircraft was plywood. The maximum aft centre
of gravity (CG) limit was determined to be 152.2 in. The
CG of the occurrence aircraft was calculated to be 154.8 in.
aft of the datum, 2.6 in. behind the rearward limit.
The aircraft was loaded in a manner that resulted in the
CG being aft of the rearward limit. The smooth surface
of the finished lumber provided less friction against the
plywood cabin floor. The cargo was only secured with one
lateral strap and it is likely that the shorter finished boards
moved aft during the taxi and take-off roll, which would
result in a significant rearward shift of the CG.
The rearward shift of the CG during the taxi and take-off
roll resulted in the aircraft pitching nose up, stalling and
entering an incipient spin from which the pilot was not
able to recover.
Findings as to causes and contributing factors
1. The aircraft was loaded in a manner that resulted in the
centre of gravity being aft of the rearward limit.
2. Because the cargo was not properly secured, it shifted
towards the rear of the aircraft, resulting in the centre
of gravity moving further aft, causing the aircraft to
pitch up and stall.
On August 30, 2007, the TSB issued Safety Advisory
A07W0099-D1-A1 (Inadequate Cargo Restraint) to
Transport Canada. The safety advisory suggested that
Transport Canada may wish to inform industry of the
significance of load shifting on aircraft performance and
the need to effectively secure cargo in order to reduce the
risk of in-flight load shift. The advisory was published in
the Aviation Safety Letter, issue 2/2008.
The engine lost power and flamed out for undetermined
reasons. While no discrepancies that would have prevented
normal operation of the engine were identified during
bench testing of the Bendix fuel control components, small
amounts of unidentified solid contamination were found in
several components after disassembly. While small amounts
of solid contamination were present, the fuel system
components functioned satisfactorily during bench testing;
therefore, the possibility that contamination contributed to
the loss of power could not be proven or ruled out.
The fuel load on the helicopter at the time of the
occurrence could not be determined with certainty,
and water contamination was present throughout the
engine and airframe fuel systems when the wreckage was
recovered. The fuel cell was breached during the accident,
which would have allowed water to flow into the fuel cell
after the wreckage became submerged. With collective
twist grip in the ground idle position and the engine
fuel check valve leaking at low pressure, water may have
been distributed throughout the fuel system by the boost
pumps after the fuel cell filled with water, before the battery
became discharged.
ASL 2/2011
25
Regulations and You
Regulations and You
Safety Action
Analysis
Recently Released TSB Reports
Recently Released TSB Reports
Analysis
Maintenance and Certification
Accident Synopses
1. The engine lost power and flamed out for
undetermined reasons on approach to the Cline River
helipad and the helicopter ditched in Abraham Lake.
2. The approach was conducted over water, toward a
sloping shoreline that exposed the helicopter to an
adverse forced landing environment.
1. Small amounts of unidentified solid contamination
were found in several engine fuel system components
after disassembly, creating the potential for fuel flow
anomalies to occur within the engine fuel system.
2. A small air leak was present in the Pc tube, situated
between the governor and the FCU, at the “B” nut on
the aft side of the governor tee. There was a risk of
engine deceleration had the leak rate increased.
3. There was a crack in the end flare on the main fuel line
in the fuel cell, where the line attached to the reducer
tee-fitting on the aft boost pump. At low fuel levels, the
engine-driven fuel pump can draw air into the system
if the boost pumps become inoperative.
5. The engine check valve assembly, located in the fuel
line between the FCU and the fuel nozzle, had a
substantial internal leak, increasing the risk of drainage
of fuel into the combustion case when the engine was
not operating.
6. The torque paint on the PTG “B” nuts was
discontinuous, leaving no way to confirm visually any
loosening of the “B” nuts.
26
3. A functioning crash-protected cockpit video digital
recorder (CVDR) may have allowed investigators to
reconstruct the flight sufficiently to better understand
the circumstances that led to the accident.
Safety action taken
Following the accident, Transport Canada completed a
limited combined regulatory inspection of the operator’s
field operation base at the Cline River Heliport. A
more in-depth inspection was subsequently carried
out by Transport Canada Aircraft Maintenance and
Manufacturing (AMM). There were 10 inspection findings
in total, most identifying administrative deficiencies.
The specialty areas that had findings were quality
assurance (QA), technical records, sample aircraft for
conformance, maintenance planning, defect recording,
rectification, deferral and control procedures, and
technical dispatch procedures. The operator responded
immediately by implementing a comprehensive corrective
action plan (CAP). An aviation consulting company
was contracted to assist in dealing with and rectifying
the deficiencies.
As a follow-up to this occurrence, the parts supplier who
shipped an incorrect PTG to the operator conducted
an internal review of the circumstances leading to this
incorrect shipment. The review employed a Maintenance
Error Decision Aid (MEDA) process. The review
resulted in four internal MEDA recommendations for
error prevention:
• Encourage the customer to identify the part number
required, and provide a purchase order when
ordering parts.
• Ensure that parts requests are entered electronically, so
as to provide an electronic trail to enable checking of
parts prior to shipment.
• Ensure that the parts are correctly identified before
removing them from inventory.
• Additional human factors training for the
employee involved.
As a follow-up to this occurrence, the contracted AMO
provided additional individual staff training, in accordance
with the Maintenance Policy Manual (MPM), as necessary
to upgrade the knowledge and understanding of the
requirements of the MPM with regards to receiving of
ASL 2/2011
Regulations and You
Regulations and You
4. The wrong PTG was installed on the engine, creating a
situation of potentially degraded engine performance.
2. Each parameter of engine data acquisition unit (DAU)
data was being averaged and recorded once per minute,
which reduced the amount and usefulness of the data
for accident investigation purposes.
Recently Released TSB Reports
Recently Released TSB Reports
Findings as to risk
1. The company did not maintain current engine
technical records in accordance with the requirements
of Section 605 of the Canadian Aviation
Regulations (CARs).
Accident Synopses
Findings as to causes and contributing factors
Other findings
Maintenance and Certification
Several maintenance-related anomalies were identified
during the examination of the engine and airframe.
The missing engine data plate, the absence of a current
engine log, and the installation of an incorrect power
turbine governor (PTG) were indicative of administrative
deficiencies, specifically maintenance tracking and record
keeping, within the company maintenance program. The
leaking compressor discharge pressure (Pc) pneumatic
tube, the lack of continuous torque paint on the PTG “B”
nuts, the crack in the reducing-tee in the fuel cell, and the
internal leak in the check valve assembly in the fuel control
unit (FCU) to fuel nozzle fuel line were further indications
of weak maintenance practices. While none of these
anomalies could be linked directly to the loss of engine
power, their presence indicated that maintenance on the
helicopter was not being accomplished fully in accordance
with the maintenance control manual (MCM) from the
contracted Approved Maintenance Organization (AMO),
or the operator’s MCM.
Maintenance and Certification
Accident Synopses
On August 24, 2007, at about 1900 Pacific Daylight
Time (PDT), an Aerostar S77A hot air balloon was
being prepared to launch for a sightseeing flight from a
field near the Hazelmere trailer park in Surrey, B.C. The
balloon was operated under a Special Flight Operating
Certificate from Transport Canada (TC) and was loaded
with a pilot and 12 passengers in the balloon’s basket. It was
fastened to its trailer by a strap to prevent the balloon from
ascending prematurely.
The number 4 cylinder fuel line was not secured, unlike
the standard fuel lines which were routed along the basket
uprights and placed inside leather sleeves to minimize
their exposure and stresses. The tank valve of the number
4 cylinder was the only tank valve determined to be open,
therefore the number 4 cylinder was the fuel source for the
fire. As burner C had metallic remains of the full length of
the number 4 fuel line connected to it, the number 4 fuel
line must have become disconnected at the number 4
cylinder tank valve. The pop and hiss sounds heard by
both the pilot and ground crewman are explained by the
fuel line disconnecting and propane under pressure being
expelled. Ignition was probably provided by the test burn
which had just been made or by the pilot light, as the loose
fuel line whipped around and propane discharged from the
number 4 cylinder under pressure.
The pilot’s practice was to coil the number 4 cylinder fuel
line around the cylinder when not in use. That practice, in
addition to the practice of connecting and disconnecting
the line during every flight, probably led to more stress on
the tank valve/fuel line connection. This extra wear and tear
likely led to the hose pulling out of its end fitting.
Balloon lifting trailer
Balloon Information
The balloon was originally manufactured with two burners
and three 23-gallon capacity propane cylinders installed in
the basket. The pilot/owner had replaced the two burners
with a three-burner installation which was approved by the
manufacturer as part of the type design of the aircraft. He
had also installed a fourth cylinder, of 15-gallon capacity,
As the number 4 cylinder was the source of the propane
fuelling the fire, closing that cylinder’s tank valve would
have removed the fuel source and likely extinguished the
fire. However, considering the ferocity of the fire, this
was not practical. An emergency fuel shut-off, such as
is generally provided in other aircraft fuel systems, was
not fitted.
ASL 2/2011
Regulations and You
Regulations and You
Analysis
Recently Released TSB Reports
An intense, uncontrolled, propane-fuelled fire occurred.
The pilot ordered the passengers to evacuate the basket and
then proceeded to evacuate himself. The balloon rose to
the limit of its tethering strap. Some of the passengers still
on board jumped from the burning basket as the balloon
climbed. The fire affected the tethering strap and it failed
from tensile overstress and the balloon climbed without
control. The balloon continued to climb until the envelope
collapsed and the burning wreckage fell into a nearby
trailer park, setting three mobile homes and two vehicles on
fire. Two passengers, who did not evacuate the basket, were
fatally injured. Several other passengers suffered serious
injuries, some with serious burns. The pilot suffered burns.
No persons on the ground were injured. Three mobile
homes, two vehicles, and the balloon were destroyed.
The aircraft journey log indicated that the balloon had
flown approximately 1272 hours since manufacture. The
balloon was being maintained by an AME who had been
performing the 100-hour inspections for the past 14 years.
If the balloon required maintenance as a result of these
inspections, it was sent to a repair facility. The AME who
performed the 100-hour inspections was unable to provide
any documentation of work performed during the past
14 years.
Accident Synopses
Recently Released TSB Reports
TSB Final Report A07P0295—Hot Air Balloon
Accident
in the basket. This modification was not approved by the
manufacturer as part of the type design, nor was it approved
by TC. No documentation was produced by the operator
to show that this installation was performed or signed-off
by an aircraft maintenance engineer (AME). The pilot
had instituted the practice of using an auxiliary 10‑gallon
portable cylinder for initial filling of the envelope with hot
air. It was not installed, but placed in the basket for the hot
inflation, and removed when its propane was exhausted.
The manufacturer was not aware of this practice.
Maintenance and Certification
parts. As well, an MPM amendment was generated to
address the use of owner-supplied parts.
27
Maintenance and Certification
Accident Synopses
Accident Synopses
Maintenance and Certification
S77A manufacturer’s three-burner configuration
The basket was the largest available for this balloon and
calculations indicate that the gross weight, with twelve
passengers on board, was substantially greater than the
maximum allowable gross weight. This increased weight
meant more lift was required. More fuel would therefore
have to be burned to create the hot air for the added lift.
The original configuration of the fuel system did not
provide sufficient fuel at the increased weight for the
average flight duration. The operator had modified the
balloon with a fourth fuel cylinder to provide greater lift
and flight time.
Although the operator was operating under a valid TC
special flight operations certificate (SFOC) stating that it
was adequately equipped and able to conduct a safe balloon
operation carrying fare-paying passengers, no inspection of
the company was ever made to support this statement. The
SFOC has no expiry date and there are no audits of balloon
operators. Had there been periodic inspections by TC, the
owner’s modifications to the balloon’s configuration and
variations from the manufacturer’s Continued Airworthiness
Instructions may have been raised as safety concerns.
28
1. The fuel line connecting the number 4 cylinder to
burner C became disconnected at the tank valve
connection, probably due to a combination of age, wear,
handling, and allowing propane under pressure to be
expelled. The propane was ignited either by flame from
the test burn just made from burner C or from the
pilot light.
2. As there was no emergency fuel shut-off and the
number 4 tank valve was open, propane continued
to be expelled through the number 4 tank valve, thus
feeding the fire.
3. Modification of the balloon from the manufacturer’s
configuration by the addition of cylinder number 4 and
the use of an additional auxiliary cylinder (number 5)
for initial envelope hot inflation contributed to the
likelihood of hose/valve discontinuity because of extra
wear and handling.
4. Operation at a weight greater than the
maximum gross weight required more fuel which
resulted in modifications being made to the
balloon’s configuration.
5. Lack of oversight by the regulator allowed the
modifications to the balloon’s configuration and
ASL 2/2011
Regulations and You
Regulations and You
Contrary to the airworthiness limitation in the
manufacturer’s Continued Airworthiness Instructions,
envelope repairs comprised more than 65 per cent of
the envelope.
Findings as to causes and contributing factors
Recently Released TSB Reports
Recently Released TSB Reports
S77A modified configuration
Maintenance and Certification
7. During the initial envelope inflation, the balloon was
fastened to its trailer, which was in turn attached to
a pick-up truck. When the fire started and people
began to evacuate the basket, the balloon began to rise
because the emergency deflation system had not been
activated. As people continued to evacuate the basket,
they had to jump from a considerable height. Some
suffered more serious injuries as a result of striking
the trailer.
8. The safety briefing given to passengers prior to their
boarding the balloon did not adequately explain how
they were to exit the balloon basket in the event of
an emergency.
Finding as to risk
1. The use of a home-made manifold to refuel all five
cylinders at once allowed the escape of a significant
amount of propane once the tank valves were closed,
after the tanks were filled. This posed a risk of fire at
the service station.
Recently Released TSB Reports
1. The lack of explicit instructions prohibiting power
recovery autorotations in the AS 350 rotorcraft
flight manual (RFM) resulted in the operator’s
training pilots adapting a practice of fuel flow control
lever (FFCL) operation that was contrary to the
manufacturer’s intent.
2. The training pilot retarded the FFCL with the
intention of executing a power recovery autorotation.
The engine did not respond as anticipated when the
FFCL was advanced for the overshoot and a high rate
of descent ensued.
3. The autorotation was flown at a higher-thanrecommended airspeed which, coupled with the steep
turn, increased the rate of descent. This high rate of
descent could not be arrested prior to contact with
the ground because of the low-energy state of the
main rotor.
4. Both pilots suffered severe back injuries due to the hard
landing. Neither pilot was wearing a shoulder harness;
this likely contributed to the severity of their injuries.
TSB Final Report A08A0007—Hard Landing—
Power Recovery Autorotation
5. The training pilot suffered severe facial injuries. He
was not wearing a helmet; this likely contributed to the
severity of his injuries.
Regulations and You
On January 10, 2008, a Eurocopter AS 350 BA
helicopter, with two pilots on board, departed the
St. John’s International Airport, N.L. to conduct annual
recurrent training. Upon arriving in the training area
at 1433 Newfoundland Standard Time (NST) at
approximately 600 ft above ground level, the training pilot
retarded the fuel flow control lever to simulate an engine
failure. The pilot commenced an autorotation. Nearing the
end of the exercise, the fuel flow control lever was advanced
to restore power to the engine with a view to executing
an overshoot. The engine (a Turbomeca Arriel 1B, serial
number 4193) did not spool up as expected. The pilot
continued the autorotation, contacting the ground at a high
rate of descent. Both pilots sustained serious injuries; the
helicopter was destroyed.
The other pilot was wearing this helmet and did not incur
head injuries; scarring on his helmet indicates contact with
the helicopter structure during impact sequence.
ASL 2/2011
Recently Released TSB Reports
1. Repairs to the fabric of the balloon envelope were in
excess of 65 per cent, contrary to the airworthiness
limitation in the manufacturer’s Continued
Airworthiness Instructions.
Findings as to causes and contributing factors
Accident Synopses
Accident Synopses
6. The strap securing the balloon to the trailer was made
of a synthetic material which was susceptible to heat
damage and failed in tensile overstress, releasing the
balloon with two passengers still on board.
Other finding
Regulations and You
Maintenance and Certification
variations from the manufacturer’s continued
airworthiness limitations to go unchallenged.
29
Maintenance and Certification
Other finding
1. While the rotor RPM was within the autorotation
range, it was not set at its optimum setting, reducing
the energy state of the rotor.
Safety action taken
The operator has issued the following safety memos:
• Shoulder harness—addressed to all pilots, advising that
the use of the shoulder harness is mandatory.
• Autorotation in AS 350-series helicopters—addressed
to all pilots, advising them that unless intending to do
a full-on practice autorotation, manipulation of the
throttle in flight is not authorized. This includes power
recoveries and surprise autorotations.
• Autorotation RPM verification—addressed to all
pilots and maintenance engineers, instructing them
to record all required parameters, such as weight,
altitude, temperature, speed, and rotor RPM,
anytime autorotation RPM verification flights have
been conducted.
Recently Released TSB Reports
TSB Final Report A08H0002—Runway Incursion
30
Analysis
When a tower controller is about to begin operations on
another runway, a request for its ownership and control
is made. When a tower controller is finished using a
runway, its ownership and control is usually transferred to
the ground controller. In this occurrence, the north tower
controller needed the ownership and control of Runway 05
to accommodate impending arrivals, but still needed
ownership and control of Runway 33L to accommodate
the delayed departure of the Boeing 737. Ownership and
control of Runway 05 had been transferred to the north
tower controller, but ownership and control of Runway 33L
had not been relinquished to the north ground position.
The north ground controller expected ownership
and control of Runway 33L to be relinquished to the
north ground position when ownership and control of
Runway 05 was transferred to the north tower controller.
The sighting of Tech 37 on Runway 33L by the north
ground controller likely confirmed in the mind of the
north ground controller that Runway 33L was no longer
in use for aircraft departures and was indeed under north
ground control. Moreover, the location of the north ground
controller position in the tower made surveillance of the
south end of Runway 33L problematic and likely prevented
the north ground controller from seeing the Boeing 737
near the threshold.
ASL 2/2011
Regulations and You
On July 28, 2008, a Boeing 737-700 was on a scheduled
flight from Toronto Lester B. Pearson International
Airport (LBPIA), Ont., to Vancouver, B.C. At
approximately 1141:50 Eastern Standard Time (EST),
the north ground controller, believing that Runway 15
right/33 left (15R/33L) was under the control of the north
ground position, cleared three emergency services vehicles
to enter Runway 15R/33L en route to the fire training area.
At 1142:27, the Boeing 737 was cleared for takeoff from
Runway 33L. The aircraft was approximately one-third
of the way down the runway when the vehicles entered
Runway 15R. The flight became airborne approximately
2500 ft from the vehicles.
Toronto LPBIA diagram
Recently Released TSB Reports
Eurocopter has developed a proposed supplement for the
AS 350 RFM that deals with engine emergencies training
procedures. The proposal provides explicit instructions on
the procedure to be followed for practice autorotations,
for both FFCL and twist grip engine controls. Regulatory
approval is pending.
Accident Synopses
Accident Synopses
1. Practice autorotations over unsuitable terrain could
result in injury and aircraft damage should a forced
landing be required.
The company has implemented a policy of cost sharing and
interest-free loans to facilitate flight helmet purchase by
the company’s pilots. Many pilots have taken advantage of
this offer and more pilots are now wearing helmets during
flight operations.
Regulations and You
Maintenance and Certification
Finding as to risk
The north service road provides access from the north fire
hall to the fire training area as well as to many other areas
around the airport without the need for vehicles to traverse
airport manoeuvring areas utilised by aircraft. There was no
operational need, in this instance, for the ARFF vehicles to
be present on the airport manoeuvring area en route to the
fire training area.
Finding as to causes and contributing factors
1. Believing Runway 33L to be under the control of the
north ground position, the north ground controller
cleared the ARFF vehicles onto that runway, leading to
a conflict with the departing Boeing 737.
Maintenance and Certification
Findings as to risk
2. Where ARFF vehicles do not need to use the runways,
their unnecessary presence on a runway increases the
risk of incursions, especially during a runway change.
Safety action taken
NAV CANADA reviewed its procedures involving
runway ownership. As a result, a new runway surface
indicator (RSI) was designed and implemented in
early September 2008. This system operates within
EXCDS (extended computer display system), allowing
visibility at all positions within Toronto tower, as well as
a recording of all actions associated with the application.
Both the EXCDS and phraseology manuals have been
updated to reflect the current standard of operation.
The Greater Toronto Airports Authority (GTAA) initiated
a communication process to assist in mitigating risk, which
requires emergency services to notify NAV CANADA
prior to conducting training exercises that involve crossing
the airfield. The GTAA will monitor this process to ensure
ongoing effectiveness. These on-field training exercises are
deemed to be essential for vehicle operators to ensure that
they maintain a level of proficiency to minimize the risk of
an incursion.
Accident site
Aircraft Information and Operation Approval
The aircraft was heavily modified, in accordance with
a Federal Aviation Administration (FAA) approval, to
enable parachuting operations. Since February 2003,
the aircraft had been registered in the United States and
was being operated seasonally in Canada under the Free
Trade Agreement (FTA) with a Canadian Foreign Air
Operator Certificate-FTA (CFAOC-FTA). The CFAOCFTA was issued annually by Transport Canada (TC) for
parachute jumping operations, recognizing the certificate
of authorization issued by the FAA to the operator. At the
time of the accident, the parachuting company was using
the aircraft for revenue parachute jumping activities.
ASL 2/2011
31
Regulations and You
Regulations and You
On August 3, 2008, a U.S.-registered Beech 65-A90
King Air took off from Pitt Meadows Airport, B.C., with
the pilot and seven parachutists for a local sky diving flight.
At 1521 Pacific Daylight Time (PDT), as the aircraft was
climbing through 3 900 ft above sea level, the pilot reported
an engine failure and turned back towards Pitt Meadows
Airport for a landing on Runway 08R. The airport could
not be reached and a forced landing was carried out in a
cranberry field, 400 m west of the airport. On touchdown,
the aircraft struck an earthen berm, bounced, and struck the
terrain again. On its second impact, the left wing dug into
the soft peat, spinning the aircraft 180 degrees. Four of the
parachutists received serious injuries and the aircraft was
substantially damaged. There was no fire and the occupants
were evacuated. The emergency locator transmitter
functioned at impact and was turned off by first responders.
Recently Released TSB Reports
Recently Released TSB Reports
1. The absence of an effective method for indicating
runway ownership and control increases the likelihood
of incursions.
TSB Final Report A08P0242—Uncontrolled
Descent into Terrain
Accident Synopses
Accident Synopses
Convinced that the north ground position had ownership
and control of Runway 33L, the north ground controller
cleared the aircraft rescue and firefighting (ARFF)
vehicles onto the runway, leading to the conflict with the
Boeing 737.
The GTAA reiterated that airport traffic directives and
the associated airport vehicle operator’s permit (AVOP)
training program indicate and inform AVOP applicants
that the service roads should be used whenever possible and
that an operational need is required to be present in the
manoeuvring area.
Maintenance and Certification
Runway ownership and control transfer is accomplished
verbally. There is no visual indication or process to inform
controllers of runway ownership, nor is there any physical
act performed to confirm controller ownership of runways
when changing runway operations.
Maintenance and Certification
The general condition of the aircraft, the condition of the
fuel systems, the engine TBO over-run, and the missed
inspection items demonstrated inadequate maintenance.
The regulatory oversight in place was inadequate because
the inspection carried out by the FAA in April 2008 did
not identify any of these issues. Furthermore, TC did not
carry out any inspections of this operation.
Maintenance and Certification
required in the maintenance instructions, the spline wear
and corrosion should have been detected.
Findings as to causes and contributing factors
1. The general condition of the aircraft, the engine
TBO over-run and the missed inspection items
demonstrated inadequate maintenance that was not
detected by regulatory oversight.
Left engine drive splines and coupling
Accident Synopses
3. The left engine lost power due to mechanical failure of
the engine fuel pump drive splines.
Close-up of external spline wear
A sudden yaw to the right is normally associated with a
right-engine power loss. Although the pilot verified the
engines’ instruments, he did not correctly identify the left
engine as the failed engine. This was likely due in part
to the horizontal layout of engine instrumentation that
makes timely engine malfunction identification difficult.
Moreover, the pilot had not received any training on the
King Air for over two years, decreasing his ability to react
appropriately. This resulted in the pilot erroneously shutting
down the operating engine.
Because the engines were being operated “on condition,”
the left engine was operated more than 800 hours
past the time before overhaul (TBO) required by the
engine manufacturer. Had the 3600-hour overhaul been
accomplished, or the phase inspection completed as
32
5. Not using the restraint devices contributed to the
seriousness of injuries to some passengers.
Finding as to risk
1. There is a risk to passengers if TC does not verify that
holders of CFAOC-FTA meet airworthiness and
operational requirements.
Safety action taken
Aircraft Owner
After the accident, the aircraft owner requested that a sister
aircraft have its fuel system inspected while undergoing
maintenance at an approved maintenance organization
in Calgary, Alta. Those inspections revealed numerous
heavily corroded components and jelly formed by microbial
growth. The fuel drained from the tanks and system was
described as milky and was disposed of.
Transport Canada
The Foreign Inspection Division has taken steps to ensure
that the regions are notified of foreign air operators
that have been issued a CFAOC-FTA for operations
in Canada. Procedures will be documented in its staff
instruction handbook indicating that the regions are to be
notified by e-mail of a CFAOC-FTA operation with the
location and dates. ASL 2/2011
Regulations and You
Regulations and You
It was concluded that mechanical failure of the left-hand
engine fuel pump drive splines resulted in the loss of
power from that engine. The bang, the shuddering, and
the yaw to the right that was experienced may have been
caused by the left-hand engine fuel pump drive splines
disengaging momentarily and then re-engaging. This
disengagement would have caused the engine to flameout,
and the re-engagement would have caused a relight with
a corresponding bang. This would have been accompanied
by a surge of power which could have caused the aircraft to
yaw to the right.
Recently Released TSB Reports
Recently Released TSB Reports
Analysis
4. The horizontal engine instrument arrangement and the
lack of recent emergency training made quick engine
malfunction identification difficult. This resulted in the
pilot shutting down the wrong engine, causing a dualengine power loss and a forced landing.
Accident Synopses
2. The TBO over-run and missed inspections resulted
in excessive spline wear in the left engine-driven fuel
pump going undetected.
Maintenance and Certification
Accident Synopses
— On August 6, 2010, a privately operated Cessna 177B
was on the landing roll on a gravel road approximately
10 NM west of Shellbrook, Sask., when the left wingtip
contacted tree branches to the left of the road. The pilot
lost directional control and the aircraft swerved left into a
ditch adjacent to the road. The nose landing gear collapsed
and the aircraft was substantially damaged. The pilot was
uninjured. TSB File A10C0137.
— On August 13, 2010, an Air Creation
MILD GTE 582S basic ultralight took off from
Chambly Airport, Que., with the pilot on board. Soon
after takeoff, for an unknown reason, the pilot attempted
an emergency landing on Highway 10. On final, the
aircraft struck high voltage lines and then crashed on
Highway 10. The aircraft was significantly damaged and
the pilot was seriously injured. TSB File A10Q0131.
— On August 14, 2010, a Wag-Aero Cuby on floats
took off from Lake Témiscouata, Que., with a pilot and
one passenger on board. Some 50 ft above the surface of
the water, the floatplane began an uncommanded turn
to the left, which the pilot was unable to control. In the
next few moments, the aircraft nosed down and hit the
lake’s surface where it came to a standstill on its floats.
The aircraft was significantly damaged. The two occupants
were both wearing life jackets when they took off. They
were rescued by some recreational boaters who were on
the lake. TSB File A10Q0130.
— On August 18, 2010, a Bell 206B helicopter was
inbound to Bischoff Lake, B.C., with three people on
— On August 19, 2010, a Cessna U206G was
on a VFR flight from Fort McMurray, Alta. to
Fort Chipewyan, Alta. While en route, the pilot noted
that the oil pressure was low. After contacting company
aircraft in the area, it was decided to divert to the nearest
aerodrome in Embarras, Alta. The oil pressure continued
to fall, the propeller RPM surged, and the manifold
pressure dropped. At 1 000 ft AGL, oil began to spray
from beneath the engine cowling because the No. 6
cylinder connecting rod had penetrated the crankcase.
The engine (Teledyne Continental IO-520-F) was shut
down and a forced approach into a wooded area was
executed. The aircraft was substantially damaged. The pilot
and four passengers were not seriously injured and were
taken to Fort McMurray by helicopter later that evening.
TSB File A10W0136.
— On August 29, 2010, a Wag-Aero Sportsman 2+2,
with a pilot and one passenger on board, left on a fishing
trip from Lac Sébastien, Que., without a flight plan
and without informing anyone of their destination.
The aircraft and its occupants were reported missing
on Sunday, August 29, and were found on the evening
of August 31, some 78 NM northeast of Lac Sébastien
near the Pipmuacan Reservoir and Lac du Fakir.
TSB File A10Q0146.
— On August 31, 2010, the owner of an Aeronca 7EC
wanted to ground-test the engine but the aircraft took
off and crashed about half a mile from the runway. The
ASL 2/2011
33
Regulations and You
— On August 15, 2010, a Dassault Falcon 900 EX was
on the ramp at Medicine Hat, Alta. The aircraft began
taxiing to the runway and struck a fence post with the left
wing tip. The aircraft was subsequently grounded and is
awaiting replacement parts. TSB File A10W0135.
board. The pilot chose a landing area on the southwest
side of the lake. Bischoff Lake’s elevation is 6 500 ft ASL
and the ambient temperature was 25°C. As the aircraft
approached the selected landing area, the pilot judged that
the aircraft was moving too fast. The landing was rejected
and a go-around was initiated. Power was increased to
climb but the helicopter began to descend, even though
torque was at 100 percent. The pilot pulled up on the
collective but the helicopter continued to descend and
began to yaw to the right. The helicopter continued
to descend and rotate faster; the low rotor RPM horn
sounded. Rotor RPM was at 90 percent. The pilot steered
the helicopter to an area that was largely free of rocks. The
helicopter hit the ground and rolled to the right. The pilot
turned off the fuel and battery, and helped the passengers
evacuate. The helicopter was substantially damaged; there
were no injuries. TSB File A10P0273.
Recently Released TSB Reports
Recently Released TSB Reports
— On August 2, 2010, a privately operated
Cessna A185E on amphibious floats was taking off from
Lake Couchiching, near Orillia, Ont., on a VFR flight to
the Orillia/Lake St. John water aerodrome. After getting
on the step during the take-off run, the aircraft struck a
boat’s wake and nosed over. The landing gear structure
was damaged and the propeller struck one of the floats.
The aircraft remained upright and was towed to a dock
without further damage. TSB File A10O0160.
Accident Synopses
Regulations and You
Note: The following accident synopses are Transportation Safety Board of Canada (TSB) Class 5 events, which occurred between
August 1, 2010, and October 31, 2010. These occurrences do not meet the criteria of classes 1 through 4, and are recorded by the
TSB for possible safety analysis, statistical reporting, or archival purposes. The narratives may have been updated by the TSB
since publication. For more information on any individual event, please contact the TSB.
Maintenance and Certification
accident synopses
— On September 6, 2010, a Schweizer G-164A Ag-Cat
was on a VFR ferry flight from Kapuskasing, Ont. to
Elliot Lake, Ont. Weather began to deteriorate about
20 NM north of Elliot Lake and the aircraft descended to
maintain visual contact. While attempting to cross over a
ridge about 3 NM north of the airport, visual contact was
lost and the aircraft struck a tree with one wing, swiveled
around and went nose-down towards the ground, coming
to rest intact, supported mainly by trees and shrubs.
After evacuating the aircraft, the pilot determined that
there was no fire, returned to the aircraft, turned on the
electrics, and contacted an overflying commercial flight
on 121.5 MHz. The emergency locator transmitter (ELT)
was not activated. The site was later located by a police
34
Maintenance and Certification
Recently Released TSB Reports
— On September 15, 2010, a Taylorcraft BC12-D was
on final approach to land on the pilot’s private strip,
approximately 25 NM east of Dorval, Que., when the
aircraft struck wires. The aircraft flipped over and came
to rest upside down. The passenger was seriously injured.
The pilot sustained minor injuries. The aircraft was
substantially damaged. The occurrence took place at dusk.
TSB File A10Q0156.
— On September 19, 2010, an Explorer advanced
ultralight on pneumatic floats had taken off from
the St-François River at water aerodrome CSA7 in
Drummondville, Que., for a local flight. During the flight,
the pilot suddenly felt a full deflection of the two rudder
bar pedals. As a result, the aircraft yawed to the right and,
despite application of the left aileron, the aircraft became
difficult to control. The pilot made an emergency landing
on a stretch of highway that was under construction. On
contact with the gravel, the aircraft bounced and turned
off toward a ditch. The aircraft was heavily damaged and
the right wing was broken. The pilot sustained minor
ASL 2/2011
Regulations and You
Regulations and You
— On September 5, 2010, an amateur-built Christavia
Mark 1 took off from a private strip near Lumby, B.C. in
gusty wind conditions. Shortly after takeoff, the aircraft
appeared to experience control difficulties and stalled.
The aircraft impacted the ground in a field near the strip.
There was a post-impact fire. The pilot and passenger did
not survive. TSB File A10P0288.
— On September 12, 2010, a de Havilland Dash 8-400
had landed and all gates were occupied. The captain
taxied to the de-ice bay and shut down both
engines. Once a gate became free, the captain
elected to start only the No. 2 engine and
taxied to the gate. Applying the brakes did
not stop the aircraft and the nose cone and
nose gear impacted a tug, causing damage and
a hydraulic leak. The right propeller struck a
ground power unit. The tip of the propeller
broke off and damaged two cabin windows.
There were no reported injuries. The No. 1
engine contains the engine-driven hydraulic
pump and when the No. 2 engine was started,
the standby AC hydraulic pump was not
selected, so no hydraulic pressure was available
for the brakes. The No. 2 engine and propeller
will be replaced due to the propeller strike.
An SMS evaluation will be conducted by the
operator. TSB File A10A0095.
Recently Released TSB Reports
Artist’s impression of rotor strike
— On September 12, 2010, a Piper PA-36 was applying a
herbicide in the vicinity of Milden, Sask. The landing gear
caught in an electrical line at the end of the field and the
aircraft crashed. The pilot was seriously injured and the
aircraft was substantially damaged. TSB File A10C0162.
Accident Synopses
Accident Synopses
— On August 31, 2010, an Aerospatiale AS350 BA
helicopter was dropping off two surveyors in the
Namur Lake area, Alta. The landing site was in a confined
area. The initial touchdown was successful; however,
the pilot repositioned the helicopter a short distance to
facilitate an easier exit for the surveyors. During this
manoeuvering, the main rotor blades contacted a sapling
2 in. in diameter, which resulted in major damage to all
three blades. TSB File A10W0143.
helicopter. The pilot was uninjured and the wings of the
aircraft were substantially damaged. It was noted that
weather reports were not available for Elliot Lake at
the time of the flight nor during preflight preparation.
TSB File A10O0194.
Maintenance and Certification
aircraft was significantly damaged. The pilot-in-command
was seriously injured. He had reconstructed the aircraft
and it seems that the control cables were reversed. He did
not have a pilot’s licence. TSB File A10Q0149.
Paul Marquis, Editor
Aviation Safety Letter
Transport Canada (AARTT)
330 Sparks Street, Ottawa ON K1A 0N8
E-mail: paul.marquis@tc.gc.ca
Tel.: 613-990-1289 / Fax: 613-952-3298
Internet: www.tc.gc.ca/ASL
Sécurité aérienne — Nouvelles est la version française
de cette publication.
© Her Majesty the Queen in Right of Canada,
as represented by the Minister of Transport (2011).
ISSN: 0709-8103
TP 185E
Publication Mail Agreement Number 40063845
Table of Contents
section
2
ASL 2/2011
— On September 24, 2010, the crew of a Cessna C180J
was performing training circuits on glassy water on
Little Chippewa Lake approximately 30 NM northwest
of South Indian Lake, Man. After several successful
circuits, the aircraft swung to the left when power was
applied for takeoff. The left float dug in and the aircraft
nosed over. The cabin filled quickly through the broken
windshield. The aircraft sank in approximately 10 ft of
water. The two occupants were uninjured and were able
to exit the aircraft safely. The left float was broken and
the aircraft was substantially damaged. The pilot-incommand had recently attended an underwater egress
training course. TSB File A10C0171.
— On September 26, 2010, an amphibious DHC-2
aircraft took off from Port McNeill aerodrome, B.C., on
a VFR flight to Rivers Inlet, B.C. As the weather was
marginal, the pilot became preoccupied with receiving
weather information on the radio immediately after
takeoff and did not retract the landing gear. Upon
arrival at Rivers Inlet, the pilot checked the landing gear
pressure but did not visually confirm the landing gear
position. On touch down, the aircraft overturned and
sank and the cabin filled with water. The four occupants
evacuated the aircraft successfully but none were wearing
a life jacket. As the aircraft was expected, a boat was
waiting and picked up all the occupants within five
minutes. There were no injuries, but the aircraft was
substantially damaged. TSB File A10P0308.
— On September 30, 2010, while conducting
circuits at the Kamloops Airport, B.C., the pilot of
a Piper PA‑31T Cheyenne inadvertently landed on
Runway 08 with the landing gear in the retracted
position. The pilot and passenger were uninjured but the
aircraft was substantially damaged. There was no fire.
TSB File A10P0312.
— On October 7, 2010, the pilot of a
Schleicher ASW‑15B glider was soaring in mountain
waves near Cowley, Alta. He was unable to return to
Cowley when he ran out of lift, and landed in rocky
terrain about 10 NM southwest of Cowley. The glider
was substantially damaged but the pilot was uninjured.
TSB File A10W0163.
— On October 10, 2010, a Piper PA28‑140
was on a VFR flight near the airport at
St-Georges de Beauce, Que. During the landing roll, it
seems that a wind squall caused the aircraft to swerve
to the left of Runway 24. The pilot, who was alone on
board, was unable to bring the aircraft back onto the
runway. The main wheel on the left side struck a runway
light and the left wing hit a runway sign. The aircraft
continued, crossing the ditch at the edge of the runway,
and came to a stop about 100 ft later. The pilot was not
injured. The left wheel and the propeller were damaged,
the nose wheel was torn off, and the root of the left
wing was knocked in. Reported winds were 270° at 8 kt.
Several witnesses reported a wind squall just before the
occurrence. TSB File A10Q0183.
— On October 19, 2010, a Hiller UH-12E helicopter
took off from Chetwynd, B.C. and flew to a job site
20 NM southwest. The job was to seed grass along a
pipeline. While seeding at an altitude of about 150 ft,
the engine (Lycoming IO-540) stopped. The pilot made
an autorotation into a clearing but landed hard and
rolled over. The helicopter was substantially damaged
and the pilot was uninjured. The 406 emergency locator
transmitter (ELT) was activated. TSB File A10P0337. ASL 2/2011
35
Regulations and You
Guest Editorial..................................................................................................................................................................3
Pre-Flight...........................................................................................................................................................................5
Flight Operations..............................................................................................................................................................9
Maintenance and Certification........................................................................................................................................19
Recently Released TSB Reports......................................................................................................................................23
Accident Synopses............................................................................................................................................................33
Debrief: MET Towers: A Collision Can Happen and it Has Happened…..............................................................36
The First Defence (poster)................................................................................................................................................Tear-off
Take Five: Carburetor Icing.............................................................................................................................................Tear-off
Regulations and You
page
— On September 22, 2010, a Cessna 172 on floats had
taken off from Lac du Sapin Croche, Que., for a local
flight. Upon its return, it landed on the water and then
taxied towards a cottage. When it was about 150 ft from
shore, a wind squall lifted the back part of the aircraft
and flipped it over. The pilot, who was alone on board,
was not injured. He was wearing a Mustang flotation
device and was able to swim to shore without difficulty.
The aircraft remained above water, suspended by its floats.
TSB File A10Q0161.
— On September 27, 2010, the pilot of a Cessna 152
was en route from Wawa, Ont. to Sioux Lookout, Ont.
The Sioux Lookout flight service station (FSS) received
a call from the pilot stating that he was out of fuel. The
pilot conducted a forced landing into a tilled field 6 NM
east of Sioux Lookout Airport. The aircraft impacted
the ground at a high angle and low velocity. The aircraft
was substantially damaged and the pilot was seriously
injured. Overflying aircraft reported a continuous and
strong emergency locator transmitter (ELT) signal.
They provided the coordinates of the site and directed
emergency personnel. The pilot was extricated from the
wreck and transported to hospital. TSB File A10C0174.
Recently Released TSB Reports
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injuries and the passenger was not injured. An
examination revealed that the left rudder cable had
broken as a result of excessive wear: it had been rubbing
against the floor and the steel guard on one of the pulleys.
The cable was also corroding at the point of the fracture
and the right cable was also showing signs of wear. The
diameter of the pulleys (1 in.) and that of the two rudder
cables was smaller than what is normally used. As is often
the case, the cable tension on the aircraft is provided
by return springs. When the left cable broke, the right
spring pulled on the right cable, which caused the yawing
to the right. TSB File A10Q0159.
Accident Synopses
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Accident Synopses
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Recently Released TSB Reports
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Transport
Canada
Transports
Canada
debrief
TP 2228E-38
(04/2011)
The spraying of crops by means of a specially adapted
aircraft is a common activity in rural areas. In order to
obtain the most effective application, the aircraft is often
flown at heights in the order of three to four meters
off the ground. The field, however, may also have a
meteorological (MET) tower, which is used to gather data
for analysis of the wind resource prior to the construction
of a windfarm. These towers have a tubular steel mast that
is held in position by sets of guy wires.
On June 29, 2010, an Air Tractor 502B was engaged in
aerial application near Portage la Prairie, Man., when it
collided with an unmarked metal wind power test pole
approximately 56 m high. The pilot elected to perform a
precautionary landing in a nearby field. Inspection of the
aircraft revealed damage to the propeller, right landing
gear, flap and wing leading edge, approximately 1.2 m from
the fuselage.
aviation safety letter
Feature
In most accidents involving carburetor icing, the pilot has not fully understood the carburetor heat
system of the aircraft and what occurs when it is selected. Moreover, it is difficult to understand the
countermeasures unless the process of ice formation in the carburetor is understood. Detailed descriptions
of this process are available in most good aviation reference publications and any AME employed on type
can readily explain the carburetor heat system. The latter is especially important because of differences in
systems. The pilot must learn to accept a rough-running engine for a minute or so as the heat melts and
loosens the ice which is then ingested into the engine.
mast
Flight Planning: A Critical Layer of Protection from Wake Turbulence
Instructor Refresher Courses Improve Flight Safety… and Renew your Rating
CARBURETOR ICING
D
U
FO
IT
Y
+10°
ID
0°
%
H
U
M
Serious icing - descent power
10
0
-10°
Both the mast and guy wires of a MET tower may be
quite difficult to see, depending on the ambient lighting
conditions and direction of approach. The photo below
illustrates this potential problem well.
-10°
Light icing - cruise or descent power
-18°
DEW POINT °C
G
C
LO
+20°
0°
+10°
+20°
+30°
MET towers are not normally at a height or location near
an aerodrome or recognized flight route, which would
require them to be either marked or lit, as stipulated in
Transport Canada CAR 621.19. For the same reason, they
would not be identified on navigational charts.
Debrief
AIR TEMP °C
(Source: Transport Canada Aeronautical Information Manual (TC AIM) Section AIR 2.3.)
COPA Corner: Practice Precautionary Approaches More Often
Underwater Egress Testimonials Validate Process
Major Accident Report: VFR into IMC Claims Seven
Optimistic and Ability Biases: “VFR flight into IMC won’t happen to me;
but if it does I can get out of it!”
Repair and Modification of Amateur-built Aircraft
MET Towers: A Collision Can Happen and it Has Happened…
Learn from the mistakes of others;
you’ll not live long enough to make them all yourself ...
"Debrief"
Prior to doing an aerial spraying, the pilot or operator
should always contact the field owner directly to find out
if there are any objects of concern in the field. If such a
tower cannot be readily seen under certain conditions,
there is a good chance it will not be detected by an air
reconnaissance alone. The pilot or operator should also
ask the field owner if there are any MET towers in
adjacent fields, over which the spray aircraft might make
necessary turns. -18°
+40°
NOTE: This chart is not valid when operating on automotive gasoline (MOGAS). Due to its higher
volatility, MOGAS is more susceptible to the formation of carburetor icing. In severe cases, ice may form
at outside air temperatures up to 20°C higher than with aviation gasoline (AVGAS).
The photo of the damage to the leading edge clearly
shows how fortunate this pilot was in terms of where
the aircraft struck the pole. Had the aircraft hit the pole
further out on the leading edge, aircraft control may
have been lost. According to the operator, the structural
integrity of the Air Tractor wing next to the fuselage is
believed to have allowed the aircraft to remain airworthy
and retain controllability. The top of the pole was damaged
and a galvanized guy wire ⅜ in. thick was severed. The
Transportation Safety Board of Canada issued a Class 5
report (A10C0101) on this occurrence.
Debrief
Debrief
+30°
Moderate icing - cruise power
or serious icing - descent power
In this Issue...
Reducing the Risk of Landing Accidents and Runway Overruns
The following chart provides the range of temperature and relative humidity which could induce
carburetor icing.
Serious icing - any power
TP 185E
Issue 2/2011
The June 2010 occurrence
guy wire
Feature
Carburetor Icing
Carburetor icing is a common cause of general aviation accidents. Fuel injected engines have very few
induction system icing accidents, but otherwise no airplane and engine combination stands out. Most
carburetor icing related engine failure happens during normal cruise. Possibly, this is a result of decreased
pilot awareness that carburetor icing will occur at high power settings as well as during descents with
reduced power.
by Eduard Alf, P.Eng., Visual Aids Technical Unit, Aerodromes and Air Navigation Division, Standards Branch, Civil Aviation,
Transport Canada
Debrief
Debrief
MET Towers: A Collision Can Happen and it Has Happened…
TC-1004093
36
ASL 2/2011
*TC-1004093*
Paul Marquis, Editor
Aviation Safety Letter
Transport Canada (AARTT)
330 Sparks Street, Ottawa ON K1A 0N8
E-mail: paul.marquis@tc.gc.ca
Tel.: 613-990-1289 / Fax: 613-952-3298
Internet: www.tc.gc.ca/ASL
Sécurité aérienne — Nouvelles est la version française
de cette publication.
© Her Majesty the Queen in Right of Canada,
as represented by the Minister of Transport (2011).
ISSN: 0709-8103
TP 185E
Publication Mail Agreement Number 40063845
Table of Contents
section
2
ASL 2/2011
— On September 24, 2010, the crew of a Cessna C180J
was performing training circuits on glassy water on
Little Chippewa Lake approximately 30 NM northwest
of South Indian Lake, Man. After several successful
circuits, the aircraft swung to the left when power was
applied for takeoff. The left float dug in and the aircraft
nosed over. The cabin filled quickly through the broken
windshield. The aircraft sank in approximately 10 ft of
water. The two occupants were uninjured and were able
to exit the aircraft safely. The left float was broken and
the aircraft was substantially damaged. The pilot-incommand had recently attended an underwater egress
training course. TSB File A10C0171.
— On September 26, 2010, an amphibious DHC-2
aircraft took off from Port McNeill aerodrome, B.C., on
a VFR flight to Rivers Inlet, B.C. As the weather was
marginal, the pilot became preoccupied with receiving
weather information on the radio immediately after
takeoff and did not retract the landing gear. Upon
arrival at Rivers Inlet, the pilot checked the landing gear
pressure but did not visually confirm the landing gear
position. On touch down, the aircraft overturned and
sank and the cabin filled with water. The four occupants
evacuated the aircraft successfully but none were wearing
a life jacket. As the aircraft was expected, a boat was
waiting and picked up all the occupants within five
minutes. There were no injuries, but the aircraft was
substantially damaged. TSB File A10P0308.
— On September 30, 2010, while conducting
circuits at the Kamloops Airport, B.C., the pilot of
a Piper PA‑31T Cheyenne inadvertently landed on
Runway 08 with the landing gear in the retracted
position. The pilot and passenger were uninjured but the
aircraft was substantially damaged. There was no fire.
TSB File A10P0312.
— On October 7, 2010, the pilot of a
Schleicher ASW‑15B glider was soaring in mountain
waves near Cowley, Alta. He was unable to return to
Cowley when he ran out of lift, and landed in rocky
terrain about 10 NM southwest of Cowley. The glider
was substantially damaged but the pilot was uninjured.
TSB File A10W0163.
— On October 10, 2010, a Piper PA28‑140
was on a VFR flight near the airport at
St-Georges de Beauce, Que. During the landing roll, it
seems that a wind squall caused the aircraft to swerve
to the left of Runway 24. The pilot, who was alone on
board, was unable to bring the aircraft back onto the
runway. The main wheel on the left side struck a runway
light and the left wing hit a runway sign. The aircraft
continued, crossing the ditch at the edge of the runway,
and came to a stop about 100 ft later. The pilot was not
injured. The left wheel and the propeller were damaged,
the nose wheel was torn off, and the root of the left
wing was knocked in. Reported winds were 270° at 8 kt.
Several witnesses reported a wind squall just before the
occurrence. TSB File A10Q0183.
— On October 19, 2010, a Hiller UH-12E helicopter
took off from Chetwynd, B.C. and flew to a job site
20 NM southwest. The job was to seed grass along a
pipeline. While seeding at an altitude of about 150 ft,
the engine (Lycoming IO-540) stopped. The pilot made
an autorotation into a clearing but landed hard and
rolled over. The helicopter was substantially damaged
and the pilot was uninjured. The 406 emergency locator
transmitter (ELT) was activated. TSB File A10P0337. ASL 2/2011
35
Regulations and You
Guest Editorial..................................................................................................................................................................3
Pre-Flight...........................................................................................................................................................................5
Flight Operations..............................................................................................................................................................9
Maintenance and Certification........................................................................................................................................19
Recently Released TSB Reports......................................................................................................................................23
Accident Synopses............................................................................................................................................................33
Debrief: MET Towers: A Collision Can Happen and it Has Happened…..............................................................36
The First Defence (poster)................................................................................................................................................Tear-off
Take Five: Carburetor Icing.............................................................................................................................................Tear-off
Regulations and You
page
— On September 22, 2010, a Cessna 172 on floats had
taken off from Lac du Sapin Croche, Que., for a local
flight. Upon its return, it landed on the water and then
taxied towards a cottage. When it was about 150 ft from
shore, a wind squall lifted the back part of the aircraft
and flipped it over. The pilot, who was alone on board,
was not injured. He was wearing a Mustang flotation
device and was able to swim to shore without difficulty.
The aircraft remained above water, suspended by its floats.
TSB File A10Q0161.
— On September 27, 2010, the pilot of a Cessna 152
was en route from Wawa, Ont. to Sioux Lookout, Ont.
The Sioux Lookout flight service station (FSS) received
a call from the pilot stating that he was out of fuel. The
pilot conducted a forced landing into a tilled field 6 NM
east of Sioux Lookout Airport. The aircraft impacted
the ground at a high angle and low velocity. The aircraft
was substantially damaged and the pilot was seriously
injured. Overflying aircraft reported a continuous and
strong emergency locator transmitter (ELT) signal.
They provided the coordinates of the site and directed
emergency personnel. The pilot was extricated from the
wreck and transported to hospital. TSB File A10C0174.
Recently Released TSB Reports
Copyright:
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in the Aviation Safety Letter are subject to copyrights held
by other individuals and organizations. In such cases, some
restrictions on the reproduction of the material may apply,
and it may be necessary to seek permission from the rights
holder prior to reproducing it.
The Order Desk
Transport Canada
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Internet: www.tc.gc.ca/Transact
injuries and the passenger was not injured. An
examination revealed that the left rudder cable had
broken as a result of excessive wear: it had been rubbing
against the floor and the steel guard on one of the pulleys.
The cable was also corroding at the point of the fracture
and the right cable was also showing signs of wear. The
diameter of the pulleys (1 in.) and that of the two rudder
cables was smaller than what is normally used. As is often
the case, the cable tension on the aircraft is provided
by return springs. When the left cable broke, the right
spring pulled on the right cable, which caused the yawing
to the right. TSB File A10Q0159.
Accident Synopses
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Note: Reprints of original Aviation Safety Letter
material are encouraged, but credit must be given to
Transport Canada’s Aviation Safety Letter. Please forward
one copy of the reprinted article to the editor.
Accident Synopses
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Recently Released TSB Reports
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Maintenance and Certification
The Aviation Safety Letter is published quarterly by
Transport Canada, Civil Aviation. It is distributed to
all holders of a valid Canadian pilot licence or permit,
to all holders of a valid Canadian aircraft maintenance
engineer (AME) licence and to other interested
individuals free of charge. The contents do not necessarily
reflect official government policy and, unless stated, should
not be construed as regulations or directives.
Transport
Canada
Transports
Canada
debrief
TP 2228E-38
(04/2011)
The spraying of crops by means of a specially adapted
aircraft is a common activity in rural areas. In order to
obtain the most effective application, the aircraft is often
flown at heights in the order of three to four meters
off the ground. The field, however, may also have a
meteorological (MET) tower, which is used to gather data
for analysis of the wind resource prior to the construction
of a windfarm. These towers have a tubular steel mast that
is held in position by sets of guy wires.
On June 29, 2010, an Air Tractor 502B was engaged in
aerial application near Portage la Prairie, Man., when it
collided with an unmarked metal wind power test pole
approximately 56 m high. The pilot elected to perform a
precautionary landing in a nearby field. Inspection of the
aircraft revealed damage to the propeller, right landing
gear, flap and wing leading edge, approximately 1.2 m from
the fuselage.
aviation safety letter
Feature
In most accidents involving carburetor icing, the pilot has not fully understood the carburetor heat
system of the aircraft and what occurs when it is selected. Moreover, it is difficult to understand the
countermeasures unless the process of ice formation in the carburetor is understood. Detailed descriptions
of this process are available in most good aviation reference publications and any AME employed on type
can readily explain the carburetor heat system. The latter is especially important because of differences in
systems. The pilot must learn to accept a rough-running engine for a minute or so as the heat melts and
loosens the ice which is then ingested into the engine.
mast
Flight Planning: A Critical Layer of Protection from Wake Turbulence
Instructor Refresher Courses Improve Flight Safety… and Renew your Rating
CARBURETOR ICING
D
U
FO
IT
Y
+10°
ID
0°
%
H
U
M
Serious icing - descent power
10
0
-10°
Both the mast and guy wires of a MET tower may be
quite difficult to see, depending on the ambient lighting
conditions and direction of approach. The photo below
illustrates this potential problem well.
-10°
Light icing - cruise or descent power
-18°
DEW POINT °C
G
C
LO
+20°
0°
+10°
+20°
+30°
MET towers are not normally at a height or location near
an aerodrome or recognized flight route, which would
require them to be either marked or lit, as stipulated in
Transport Canada CAR 621.19. For the same reason, they
would not be identified on navigational charts.
Debrief
AIR TEMP °C
(Source: Transport Canada Aeronautical Information Manual (TC AIM) Section AIR 2.3.)
COPA Corner: Practice Precautionary Approaches More Often
Underwater Egress Testimonials Validate Process
Major Accident Report: VFR into IMC Claims Seven
Optimistic and Ability Biases: “VFR flight into IMC won’t happen to me;
but if it does I can get out of it!”
Repair and Modification of Amateur-built Aircraft
MET Towers: A Collision Can Happen and it Has Happened…
Learn from the mistakes of others;
you’ll not live long enough to make them all yourself ...
"Debrief"
Prior to doing an aerial spraying, the pilot or operator
should always contact the field owner directly to find out
if there are any objects of concern in the field. If such a
tower cannot be readily seen under certain conditions,
there is a good chance it will not be detected by an air
reconnaissance alone. The pilot or operator should also
ask the field owner if there are any MET towers in
adjacent fields, over which the spray aircraft might make
necessary turns. -18°
+40°
NOTE: This chart is not valid when operating on automotive gasoline (MOGAS). Due to its higher
volatility, MOGAS is more susceptible to the formation of carburetor icing. In severe cases, ice may form
at outside air temperatures up to 20°C higher than with aviation gasoline (AVGAS).
The photo of the damage to the leading edge clearly
shows how fortunate this pilot was in terms of where
the aircraft struck the pole. Had the aircraft hit the pole
further out on the leading edge, aircraft control may
have been lost. According to the operator, the structural
integrity of the Air Tractor wing next to the fuselage is
believed to have allowed the aircraft to remain airworthy
and retain controllability. The top of the pole was damaged
and a galvanized guy wire ⅜ in. thick was severed. The
Transportation Safety Board of Canada issued a Class 5
report (A10C0101) on this occurrence.
Debrief
Debrief
+30°
Moderate icing - cruise power
or serious icing - descent power
In this Issue...
Reducing the Risk of Landing Accidents and Runway Overruns
The following chart provides the range of temperature and relative humidity which could induce
carburetor icing.
Serious icing - any power
TP 185E
Issue 2/2011
The June 2010 occurrence
guy wire
Feature
Carburetor Icing
Carburetor icing is a common cause of general aviation accidents. Fuel injected engines have very few
induction system icing accidents, but otherwise no airplane and engine combination stands out. Most
carburetor icing related engine failure happens during normal cruise. Possibly, this is a result of decreased
pilot awareness that carburetor icing will occur at high power settings as well as during descents with
reduced power.
by Eduard Alf, P.Eng., Visual Aids Technical Unit, Aerodromes and Air Navigation Division, Standards Branch, Civil Aviation,
Transport Canada
Debrief
Debrief
MET Towers: A Collision Can Happen and it Has Happened…
TC-1004093
36
ASL 2/2011
*TC-1004093*
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