How To Time Trial

How To Time Trial
Class Flag not less than 300mm by 200mm flown below club burgee
during competition. Raised during starting sequence at the start.
Line In Use - Raised on the start line to indicate line in use. Lowered
after last boat starts.
“P” - Preparatory signal—”The class designated by the warning signal
will start in 5 minutes”
“B” - Protest signal when flown means “I intend to lodge a protest”
“L” Flown ashore means “A notice to competitors has been posted”
When flown afloat means “come within hail” or “Follow me”
How To
Time Trial
Answering Pendant—Postponement signal
•
Alone means all events not started are postponed.
•
Over 1 ball or shape means postponed for 15 minutes
•
Over numeral pennant means postponed that number of hours
•
Over class flag means postponed till a later date
“N” Abandonment signal “The event is abandoned.”
Over the first substitute means “The event is cancelled”
First Substitute—When flown under “N” means “The event is cancelled”
“Y” Life Jackets. Means “Life jackets should be worn by all competitors”
“M” Mark Signal means “Round or pass the object displaying this signal instead of the mark it replaces.
Acknowledgements:
The following material has been modified or rewritten for this publication.
Enjoy Predicted Log / Cruiser Navigation By Tom Collins, Staff Commodore SCCA
Time Trialling Training Notes for Skippers by Garry Woods
Time Trialling Training Notes for Navigators by Peter Farrell
Skippers Presentations by Bryan Carter .
Compiled by
Peter Farrell
May 2001
12
1
W HAT EXACTLY IS TIME TRIALLING?
Time trialling is a boating activity run by yacht clubs on the Swan River and available to any members with a craft capable of navigating at a speed between 5 and 15
knots under engine power. Family participation is possible, there are a lot of husband and wife teams, and it provides an excellent opportunity to:
•
Use your boat during the winter season.
•
Learn the local waters.
•
Learn the navigational marks and hazards.
•
Learn the capabilities of your boat.
•
Familiarise yourself with the local waters.
A time trial event involves sailing and accurately maintaining a predetermined
course between fixed marks on the river at a nominated speed.
Sailing instructions are available prior to the event and courses must be followed at
the speed nominated by the comp etitor.
After starting at a given time, time checks are taken on each competitor at the start,
finish and at a number of undisclosed check points around the course. One point is
lost for each second a competitor is early or late at these check points, and penalties can be applied for obvious changes in nominated speed or diversions off
course. Time errors are cumulative, being early at one check is not cancelled by
being late at another. The winner is the competitor with the least points lost, according to the rules.
Equipment required for the event is a timing device (clock) and sailing instructions
that include a course sheet and possibly a chart if you don't know the course.
Passing a Mark to the Wrong Side
If a mark is passed on the wrong side you will be asked to retire unless
you rectify the error. If you realise that you have passed a mark on the
wrong side you must unwind it to be able to continue. To unwind return
on the same side as you initially passed it and then pass it on the correct
side.
True Course
Finally remember steer a true course, the shortest distance between any two marks is a
straight line. Failure to steer a true course may result in a penalty.
Retireme nt
If you are unable to finish or retire inform the starter personally or on Channel 94 but
not when another vessel is approaching the finish line.
Interference
If you have to slow down to give another vessel right of away near a mark and are subsequently late fly your red protest flag as soon as possible. When you finish report this
fact to the starter as soon as possible giving the mark at which it occurred and any
other information such as the boat name or competition number. You may have to accept having an average given for that mark.
Post Event
Raft Up
Preparation involves calculating your ETA at all the marks of the course from your
respective start time. Most events last between thirty minutes and two hours, depending on your nominated speed and the length of the course.
Joint the raft up. Take care to approach other vessels at slow speed and have buffers
and lines ready. Join others for drinks and visit other boats.
The variation in weather, wind, tide and the wash from other boats cause a never
ending change to conditions under which events are conducted. To those partic ipating regularly, a challenge is provided to master these variations, and in doing so,
improve their boat handling and navigation s kill.
Check Results
The fellowship of other competitors, particularly in interclub events, adds considerably to this further enjoyment of power yachting.
Sailing instructions are available prior to the event and courses must be followed at
the speed nominated by the competitor.
2
After the results are posted check your times for each mark and compare them with
those the navigator has noted on the running sheet. If there are major discrepancies
which you can’t explain you may request the Starter check the tapes. In any case you
should be able to learn something from your results for example if you are consistently early or late it could be that your clock was incorrectly set.
Enjoy your time trialling.
11
Counting down.
TIME TRIALLING IS FUN
As a guide:
There is really no secret to it. You don't have to be a mathematical wizard or a genius.
You don't need 100,000 miles of experience in your boat and reams of figures. All you
really need is some simple speed data you can easily obtain in a morning and a basic
understanding of the procedure for calculating your course and times. One more thing
you'll need is the desire to join in with a fine group of yachtsmen like yourself as you
enjoy using your boat during the contest and sharing in good fellowship afterwards at
the trophy presentation.
1.
count down each minute and
2.
then count the last minute,
•
every 10 seconds down to 30 seconds and
•
each 5 seconds down to 15 seconds and
•
each second until you pass the mark..
When you reach the mark and the skipper calls “NOW” enter the time on your running
sheet as seconds early or late or zero. You can then add the total points at the end of
the event. This enables you to check with the actual result given on the official score
sheet which is displayed after the Results are announced.
Short Legs.
Some times you get some short legs where it is difficult to count down so you may
decide to count up. For instance you call Bricklanding counting up to 10 - 5 6 7 8 9 10
SO LET'S GET STARTED
Remember, the idea is to keep it simple and to have fun ! As you become more
involved, you'll hear stories of compensating for winds, currents, weight, etc. The
important thing to remember is that you really don't need to be concerned with these
complexities. Each year many of the contests are won by novices just like you, while
some of the "scientists" outsmart themselves as they watch their theories on wind and
waves disintegrate before their eyes.
CHOOSING A SPEED
Aids to judging time
Time trialling and the yellow competition flag do not give you any extra rights on the
river. Remember you must still obey the rules of the road. You must pass vessels on
the correct side and you must give way as required by the rules of the road.
The first thing you'll need to do is to determine the speed of your boat. It's nice to have
a complete RPM speed curve, although for most contests all you really need to know is
your boat's RPM for the speeds which you intend to use for the contest (limited to 5 to
15 knots). Choose a comfortable speed, probably below the speed you normally use
for cruising. Keep in mind that during the contest you will need to increase or decrease
that speed to compensate for turns, tide or wind, so choose a speed where you and your
boat won't be knocked about if the water is a bit lumpy. One other consideration,
choose a speed which allows you room to increase or decrease your speed a little
without significantly affecting the attitude of your boat. If you have a planing hull you
need to select a speed which is a couple of knots above the speed at which the boat
planes.
Penalties -
RUNNING THE MILE
First read and become familiar with your rule book and your club red book and any
sailing instructions.
Your local chart will show the measured nautical mile course in your vicinity. The
course end points will usually be identified by a set of markers or some other fixed
object, such as a breakwater or pier. The best time to run the mile is in the morning
before the course becomes congested with other boats and the winds kick up a chop.
Set your throttle(s) carefully and run the course noted on the chart in both directions,
without stopping or changing your RPM. Use a stopwatch to measure the exact time it
takes you to travel the mile in each direction. The times you record for each direction
will probably be different due to wind and current that might be present. Times for
multiple runs in the same direction should be nearly the same.
Sometimes you might have intermediate navigational points around the course which
can assist in gauging time to a mark. How to obtain and use these should be left till
you are more experienced.
Rules of the Road.
Change of Speed
The most common penalty applied is for changes of speed and add 10 points to your
score. Remember the call is tape recorded at the marks and the check point crews
watch for changes of speed.
10
3
CALCULATING AVERAGE SPEED
You will now want to determine the average speed of your boat in seconds per nautical
mile (sec./nm). To do this, first convert the times you recorded for each direction into
seconds (example: 4 minutes and 25 seconds = 265 seconds). Now, add the times from
each direction and divide by two to determine the average speed in seconds per
nautical mile (example: 265 + 281 divided by 2 = 273 sec./nm). Divide the number of
seconds into 1 nautical mile ( 6075 ft) in this case 6075/273 = 22.25 ft per second.
Look up the chart Appendix 5 of the Time Trialling Rules and the closest are 21.96 =
13 knots and 22.8 = 13.5 knots.
It is possible to do the same by running between any two marks on the course where
the distance is known. For examp le Applecross Spit and Deepwater spit are 449 metres
apart and at 15 knots it takes 59 seconds = 7.62 m/sec.
PLOTTING THE COUR S E
The next step is to plot the contest course.
The contest instructions will list the start,
intermediate marks, and finish points as
well as the side to which they are to be
left. Once you have identified these points
on your chart, draw the course lines
interconnecting them. Now
note the
heading for each leg.
LE G TIMES
There are some speed restrictions on the river and therefore in our courses. These are
generally 8 knot areas and they are marked on the course instructions at the mark at
which the speed restriction finishes. Heathcote 8KT means there is an 8 knot limit
from SoPYC Start Line, the mark prior to Heathcote, to Heathcote.
The Marking System
Around the course there are check point teams (normally 3 people) who mark the time
you pass the mark. They are equipped with a clock, which has been set against the
master clock, and a tape recorder. One of the team counts the time from the clock as
you approach the mark, one calls when you pass the mark and the other records the
time on a sheet. Your time is recorded when the stem of the boat reaches the mark.
Technically it is the last second called before the stem reaches the mark (see illustration below where the time would be 39 seconds not 40). Competitors gain a point for
each second early or late at the mark. These points are cumulative and do not cancel
each other out. The object is to score as few points as possible. There have been a few
zero points lost. Tapes are replayed when the starting team notice any large discrepancy.
39 seconds
During the event.
The issued course sheets show the cumulative times for each mark The
leg time can be calculated by subtracting these times. Remember that
each leg is from mark to mark and does not include the time taken to
turn after reaching the mark therefore compensation must be made by
increasing the speed for the next leg. Below is an example of turn times
at a constant speed. You should of course calculate your own.
TURN ANGLE
TIME TAKEN
0 to 60 degrees
60 to 90 degrees
90 to 110 degrees
110 to 125 degrees
125 to 140 degrees
140 to 150 degrees
150 to 165 degrees
0 seconds
5 seconds
10 seconds
15 seconds
20 seconds
25 seconds
30 seconds
4
Speed Restrictions
Mark
40 seconds
For the navigator.
The method of counting down is a team effort and the skipper and navigator will determine the best method for them.
Calling the next mark
As a guide:
1.
call the name of the next mark,
2.
the side to pass and the bearing
3.
time to the mark
for instance from SoPYC Start to Heathcote may be called as " Heathcote Port
2 degrees 1 min 47".
9
Time To Next Mark
To calculate this we simply subtract the ETA at the previous mark from the ETA at
the current mark so using the example above the time from Applecross to Deepwater is
10:38:16— 10:37:07 = 1:13. This can also be done by using the running time in the
same manner.
Hints for chart marking.
If you draw your course to leave the marks on the actual side they are to be left you
can then colour them in red and green to make it easier to see at a glance whether they
are to be left to port or starboard. You can then calculate the bearings to each check
point and enter the bearings on the running sheet. Having a bearing to the check point
makes it less likely to head for the wrong mark.
165 to 175 degrees
35 seconds
Always subtract the turn-time allowance from the travel time for the leg
following the turn. The distance of the leg divided by new leg time will
give the velocity. Example time for leg = 2 min 11 secs less turn of 15
seconds 1 min 56 secs or 116 secs (NT). If the leg distance is 743.2 metres (D) the new speed is 743.2/116 = 6.4 m/s which from the Yacht
speed table given in Appendix 5 converts to 12.5 knots for the leg instead of 12 knots.
Equipment
Setting the clock
Timing device
Before you leave home you can set the clock by telecom time (phone 1194), however
when you arrive at the club you should check with the official clock and reset if necessary. While you are there check for any notices for the day, you start time and the
course number. Even champions have been known to start at the incorrect time or use
the wrong course. Don't rely on information provided by phone or the internet.
The major piece of equipment needed for this sport is a reliable clock since you are
competing to see how close to the exact time for the course you can complete it in.
You therefore require an accurate timing device. Currently competitors use a main
clock and some sort of backup clock as well as stop watches. These can be divided
into three categories;
Checking the call
•
•
•
Just prior to the event the skipper and the navigator should get together and the nav igator should call a practise time with the skipper looking over the shoulder so that the
skipper is aware of exactly how the navigator is calling their time. Skippers watch to
see if the call is before, on or after the second.
Course and Marks
•
PT - Port means that you leave the mark to the port side of your vessel.
•
STB - Starboard means leave the mark to the starboard side of your vessel.
•
CA-PT = close abeam port means that you must be close the mark leaving it to
your port
•
CAS-TB = close abeam starboard means you must be close to the mark leaving
it to starboard.
•
ST(20m) means that you must leave the mark to your starboard and be no
closer to the mark than 20 metres.
•
TRNSIT = transit . This is an imaginary line joining two fixed marks and extending through them. Examples are Foam - Concrete or Inner - Outer. Not all
clubs mark transits using them only to give intermediate times on some long
legs.
8
analogue clocks
digital clocks
computers
Analogue clocks
Analogue clocks should be selected for their accuracy, they
should be accurate to within about 1 second in 24 hours and
must have a second hand. The second hand should accurately
stop on each second mark. Clocks where the second hand
speeds up on the descent and slow down on the ascent should
be discarded.
Some sort of marker needs to be superimposed over the face
to enable the seconds to be counted backwards. In the picture
you will note that the face from a kitchen timer has been used. A pointer is set over the
actual second that the mark is to be reached.
Digital Clocks
Digital clocks need also to be very accurate. Normally 2 are used one as the main
clock and the other to count down time. The most commonly used
are pictured. Some competitors set a clock to count down to the finish time of their run. Others set the count down clock at a predetermined time from each mark in turn.
5
Computer
Preparation
Computers are used now by many competitors as they are able to enter the whole
course. One of the most commonly used (Sharp
1500A Pocket Computer) and for which a program
has been written which is easily available is pic tured. Many computers do not keep very accurate
time unfortunately. Note: the Sharp 1500A is very
old so you may have to search pawn shops or advertise to obtain one.
Before you can do any calculations you need to have obtained:
•
the course details and
•
your start time
Stop Watch
There are a variety of means whereby these may be obtained, however it is vitally important that they be checked against the official course and the officially published
starting times. Should you use the wrong course for the day or the incorrect time you
have no redress. Even Champions have been known to use the wrong course or the
wrong start time.
A stop watch is very handy for timing practice runs between marks and also for the
measured mile.
Calculate ETA
Back Up Clock
The Estimated Time of Arrival or ETA is calculated for each mark. For the Start it is
of course the start time that you are given. For each mark the ETA is the Start time
plus the running time given in course details. Look at the example below:
Anything can go wrong with a clock during an event and stories abound of them being
dropped, the batteries falling out and clocks stopping, however if you have some sort
of back up clock or watch set to the correct time all is not lost.
You can see that the Start Time is 10:30:00 so if we add the Run time to Applecross of
7:03 the ETA for Applecross is 10:37:03.
Pencils
Have spares sharpened as there isn’t any time to sharpen them during the event.
Personal Attributes
A Loud Voice
The navigator has to call and count down the time over engine noises. Navigators frequently say they “count their life away”.
A Thick Skin
To take no notice of the skipper’s tirade when things go wrong and to keep counting.
A sense humour
Needed to counteract the skipper’s usual lack of a sense of humour particularly when
things go wrong.
6
7
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement