2016 Instructor`s Meeting - Utah Soaring Association

Lynn Alley
April 5, 2016
 Approved club instruction materials, recordkeeping
requirements review
Twin Astir checkouts
Spring checkouts
Becoming an approved instructor
Winch operations
Avoiding Grob 103 PIOs
Thoughts on pattern bank angles
Fatal Accident Causes – Launch and Pre-Launch
Slack line recovery standardization
Approved Teaching Materials
For primary students:
 Holtz, Russell: Flight Training Manual for Gliders
 Holtz, Russell: Glider Pilot’s Handbook of Aeronautical
 Available at SSA online store or at
For transition students:
 Knauff: Thomas, Transition to Gliders
 Available at SSA online store or at www.eglider.org
Recordkeeping Requirements
 Holtz Training Requirements, as amended by the USA
in May, 2011
 Excel spreadsheet and PDF forms available
What is different about the Twin
 Ground handling
 Tailwheel glider
 Retractable landing gear
 Weight and balance and performance specifics
Suggested Checkout
Weight and balance considerations
Performance speeds
Preflight per POH, including items specific to that aircraft
Ground handling
Takeoff differences in tailwheel gliders
Managing landing gear retraction (don't do it when workload is high)
General handling, coordination
Stall series
Pre-landing checklist
Proper touchdown attitude
Tailwheel glider rollout and braking
Proper tiedown
Motivation for Spring Checkouts
 Pilots seem to be prone to errors – especially errors of
omission – after a prolonged period of inactivity.
Springtime is what Tom Knauff refers to as “the Silly
Season”, because so many “silly mistakes” are made.
 A spring checkout gives a pilot the opportunity to
“knock off the rust” under an instructors supervision.
Club Policy
9. Check Out Policy
A. All Members (other than USA designated instructors with passenger
carrying currency) are required to accomplish a Check Out each season
prior to flying solo or carrying passengers in a USA glider.
B. Any Member that has not flown a glider for six consecutive months will
be required to regain glider passenger carrying currency with a USA
designated Instructor.
C. During the Check Out, the instructor will determine that the Member
is proficient to exercise the privileges of his or her pilot certificate in
D. Members must notify the Board of Directors upon completion of a
Check Out by completing the online checkout form or other means
approved by the Board of Directors.
E. Notwithstanding paragraph A above, a designated USA instructor may
fly solo in order to establish currency.
(http://www.utahsoaring.org/Content/FlightOperatingRules.pdf )
Spring Checkout Suggestions
 Focus on things that mitigate against errors, such
as pre-takeoff and landing checklists
 Make sure basic skills are intact (launch, towing,
coordination, airspeed control, landing)
Club Policy
10. Instructor Approval
A. The Chief Instructor is appointed or reappointed by the
Board on an annual basis.
B. In order to obtain instructor privileges in club equipment,
an applicant must first make application to the Board.
Once approved by the board, the candidate must pass a
proficiency check administered by the club Chief
C. The Chief instructor will maintain a list of currently
approved instructors. The Chief Instructor and/or Board
will periodically review the list, and may revoke the
approval status of any Instructor for any reason at any time.
My Proficiency Check Goals
To verify (by a flight examination) flight proficiency at
the Commercial Pilot and Flight Instructor levels;
2. To verify (by oral examination) knowledge and ground
instructional proficiency; and
3. To verify (by flight examination, oral examination, and/or
review of the applicant’s experience) competency to
instruct in club equipment at a specific site, including
knowledge of local operating procedures, potential
hazards, and demonstrated soaring ability at that site. At
sites other than Morgan, this portion of the proficiency
check will be administered by my designee.
Some statistics
 51 Grob 103 Twin II and Twin II Acros registered in the US
 More than 20 of these have been involved in accidents that
resulted in a broken tail boom
 The primary cause of more than half of these accidents has
been loss of control during landing in a PIO-type event
 PIO accidents in 103s are rare in Europe
What is different about the Twin II?
What it is:
 Aft position of main wheel – makes the glider a joy
for ground handling
 Pneumatic (bouncy) nose wheel contacts the
ground at a shallow angle with a long moment arm
What it isn’t:
 The glider is not particularly pitch sensitive
 It doesn’t react unusually to speed brake changes
Sequence of a 103 “PIO”
 Initial contact occurs in a level or nose-low attitude substantially above
stall speed, with less than perfect control of vertical speed
 Aft position of main wheel (behind CG) causes A/C to rotate forward;
nose wheel strikes and bounces
 With rapidly increasing angle of attack, A/C flies again; tailwheel
strikes and bounces
 With sudden pitch down, the second contact is often directly on the
nose wheel, resulting in another, more energetic pitch up
 Pilot often exacerbates the situation with out-of-phase control inputs
The Solution
Proper touchdown attitude
 Initial contact should be made with the nose above the
 Ideally, both main and wheel should contact together,
or even slightly tail-first
Why this works:
 If the glider does not have enough energy to fly in a
nose-high attitude before the initial contact, it can’t fly
in response to a nose wheel bounce after the initial
 If touchdown attitude is nose-high, no other mistake
will result in a divergent pitch oscillation
What does Holtz Say?
Figure 6.2 – Landing attitude, with the tail wheel level with the main wheel. The tail wheel
should touch down at the same time, or slightly before the main wheel.
“Ideally, you will perform a “two-point” landing, with the main wheel
and the tail wheel touching down simultaneously, or a tail wheel-first
landing, with the tail wheel touching down slightly before the main
Note: Students in Europe and the UK are required to demonstrate this
landing technique as part of basic competency.
Instructing Ramifications
 Don’t allow students to routinely land in a level attitude on the
main wheel – the way many of our students do
 Dealing with overshoots:
 Mostly not necessary – just roll out long with a red face
 Don’t force the nose down in an attempt to make the glider land
 May be necessary to gently and smoothly increase airbrakes in
ground effect; this should not be routine, but students should
know how
 “Fixing” a PIO may not be possible., especially with student skill
level. Try to hold still with the stick slightly aft
Pattern Bank Angles – The issue
 In the power airplane world, it is not uncommon to
hear instructors say “never more than 30° in the
 Many glider instructors (particularly those influenced
by Tom Knauff) say “never less than 30° in the pattern”
Why the difference?
 Both viewpoints are motivated from a concern about
inadvertent stall/spin during either of the last two pattern
 It is interesting to note that, starting from the same
concern, the two groups come to the exactly opposite
 What is going on?
The Power Instructor’s View
 Some power instructors teach avoidance of large bank angles in the
pattern because, as everyone knows, stall speed increases with load
factor, which in turn increases with bank angle
 Note, however, that the stall comes from a commanded increase in
angle of attack in a misguided attempt by the pilot to maintain a slow
airspeed or hold a nose-high attitude
 Left on its own, a well-behaved airplane will drop its nose and speed up
in response to increasing load factor
 The temptation to pull back might be significant, and (with strong
elevator authority) an inadvertent stall can happen fairly easily
Why this isn’t as much of a
problem in gliders
 Modern type-certificated gliders are intentionally designed with weak
elevator authority – most cannot be commanded to stall when
normally loaded at bank angles much in excess of 45° (try this at
 Getting near a stall at bank angles near 45° requires substantial back
pressure, giving the pilot more warning
 The EASA CS-22 (Formerly JAR-22) standard requires significant and
increasing elevator control forces as bank angle is increased at constant
 Still possible to die this way – it just takes a bigger error
The Glider Instructor’s View
 Shallow banked turns are inefficient – they consume lots of time and
real estate
 If the pilot commits an error or experiences an emergency resulting in
an approach below normal glideslope, efficient turns are a must
 In such situations stress can become even worse because of the
unfamiliar sight picture when turning below pivotal altitude (see next
 The temptation to attempt to conserve altitude by raising the nose and
accelerate the turn by adding inside rudder becomes extreme
Pivotal Altitude
 Below pivotal altitude, the
projected line from the
banked wings moves inside
the turn center, resulting in
an unfamiliar picture that
makes normal banks appear
very steep
• Pivotal altitude is about 300
feet at 58 kts TAS
 Rope break practice is
normally below pivotal
Graphic from Steve Blackwell, cfi@learn2fly.biz
Why aren’t efficient turns as much
of a concern in airplanes?
 Big approaches don’t require efficient turns
 Power pilots can (and routinely do) recover from
below-glideslope conditions by simply adding power
 This works perfectly without any pilot stress, as long as
power is available
Instruction implications: the case
for efficient turns
 In gliders, glideslope errors and/or emergencies (such as PTT)
are inevitable; every pilot will encounter them at some point in a
normal flying career
 In order to successfully cope, a pilot must have the skill to
execute efficient, coordinated turns with proper airspeed
control, even under stress and below pivotal altitude
 Transition students, in particular, must often be taught not to
fear efficient bank angles when airspeed and coordination are
 The laws of primacy, repetition, and recency all suggest that
every approach be executed with efficient turns
10-Year Fatality Statistics
Hit Mountain
Source: Tom Knauff Safety Newsletter
Launch and Pre-Launch
Source: Tom Knauff Safety Newsletter
Instruction implications
 Teach medical factors
 Teach assembly and pre-takeoff checklists
 Teach weight and balance
 Teach pilot judgement
 Teach Premature Termination of Tow
 Teach CRM
 Train wingrunners and other crew
 Variations on ABCCCD
 Variations on CB-SIT-CB
 May not be practical to standardize
 Should not supplant written checklist
 Should always be used
 Placarded in (type certificated) gliders
Tom’s Pre-Boarding Checklist
Ballast weights
Cell Phone
Flight Recorder (memory
Oxygen bottle on?
 Pee system
 Sunglasses
 Sun block lotion
 Survival kit
 Tail dolly off
 Tape wings, ballast filled?
 Total energy probe
 Unzip Fly
 Wallet stowed
 Watch
 Water bottle
 Wing pin safetied?
Training Launch Crew
The Area
 Hazards (observers, cars, other aircraft)
 Pattern and runway clear
The Glider
 Condition, tires
 Assembly, positive control checks done
 Tail dolly
 Crew seat belts, canopies locked
The Tow Plane
 Rope checked and attached
 Condition, tires
The launch (walk to wingtip, but keep wing down until pilot signal)
 Airbrakes locked (except when pilot intentionally controlling)
 Flaps in logical position
 How to physically perform the run
Slack rope recovery – several
techniques in common use
 Yaw/Slip
 Pitch up/pitch down
 Use of high drag devices
Three phases of slack line recovery
Arrest increase in slack (slow the glider)
2. Remove slack (slow a little bit more)
3. Absorb the retensioning shock
Technique comparison
• Relatively easy to teach • Less effective at
• Generally effective
absorbing shock in
• Works in turns
C/G hook gliders
Pitch up/down
• Works in all A/C
• More difficult to
High drag devices
• Useful for large loops
• Must be augmented
with some way of
absorbing shock
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