THE HISTORY OF V.A.R.M.S The Annual Diary 1990 - 2009

41
LAUNCH HEIGHT
As the general strength of models increases and the average flying skills increase, the
launching heights achieved at contests are becoming more and more of a problem. It has
reached the stage where at most contests the average modeller with a traditional balsawoodplastic
covered model cannot hope to compete on equal terms. The strong, high performance
models can exceed the launch heights of the traditional models by so much that they more
than make up for any deficiencies in their thermalling ability; a deficiency that is becoming
more and more difficult to see as the models improve. On top of this, they can roam the skies
to such an extent than any lift will be found. The flyer of the traditional model must make
a decision to search in one area before they launch. If they do not find lift, their models do not
have the performance to fly to another part of the sky and they must therefore either accept
their flight time or re-launch.
The only solution for the traditional modeller is either to join the high technology group
and compete on equal terms, or try to change the rules to limit the launch heights by adopting
weak links in the winch line or reducing the power of the winches.
This debate will not be concluded in the near future. My view is that we should leave
the high technology route to F3B and F3J, as they are regulated International classes.
However, we need to change the rules of the Australian Open Thermal class to allow both high
tech and traditional models the chance to compete equally, and it is my belief that the only way
is to reduce the power of winches by increasing the resistance of the motors to the point where
ping launches are not possible.
.... and on the same topic from the same column in a previous Airborne (146 - August 1996),
we have the following;
The following is a letter that I received from Martin Simons in relation to my proposed
new rules for Thermal Soaring event. For those who do not know, Martin rarely takes part in
contests because he does not feel motivated by the format of the traditional Task A event.
" Your recent remarks in Airborne about thermal soaring events always seemed to me
that thermal soaring contests should be thermal soaring contests. It is a pity that the existing
rule have directed so much attention to the launch and the launching apparatus.
I was at Jerilderie over the Easter weekend, where it was demonstrated by Nic Wright
and others that, with the right launching technique, a modern F3B multi task model can win
the traditional type of thermal soaring event without actually having to do any soaring.
Providing that the air is not actually sinking, the model can stay in the air for long enough to
achieve the maximum permitted time. Even if the air for a particular hear is bad all round, the
model which is highest after the launch is most likely to win.
(History compiler's note: World F3B Champion Joe Wurts has been quoted as saying "He who
launches highest, Wins", and he should know).
Given the kind of launch altitudes measured by Nic Wright, between 220 and 250
metres, to achieve an eight minute flight requires a sinking rate of about 27 metres per minute,
or about 1.5 feet per second. Calculations published recently in the American magazine, RC
Soaring Digest, show that a lightweight floater model, like the old Olympic 2, can achieve this
sink rate. An Olympic cannot safely be winch launched at 250 km/h, however.
A modern F3B model has about the same minimum rate of sink, but it can be launched
to much greater heights, so it will, if well flown, beat the lightweight every time in the same air.
This has had the effect of concentrating all attention on the launching apparatus and the
launch technique and turned us away from thermal soaring.
A thermal soaring contest should be won by a person who can most skilfully locate and
use thermals for soaring. I can think of a competition in which competitors' attention and
ingenuity could be directed in this way. (Martin goes on to detail an extended, closed circuit, on
foot style of X-country competition that has not been reprinted here).
"Printed by kind permission of Airborne Magazine."