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  1. DT clarification
  2. No points for a slide
  3. Talk to the Elephant in the corner
  4. For those who have never seen an elephant on a free flight field.

DT clarification
From: Andrew Barron

There are some DT misconceptions in the most recent posting from our friend
Aram.  First, many fliers in F1A, F1B, and F1C use mechanical.  For myself
I usually have a mechanical available as well as electronic (and on
occasion we see good performances with each). Second, in F1A the behavior
depending on the stab angle is highly particular to the model.  For
instance, for the traditional (short and long) Stamov models and customary
spiral DT he prescribed to me an angle of 37.5 degrees, and between 35 and
39 degrees is ok. If you lower it to 34 or 35 degrees the spiral decent is
much more rapid (opposite of what Aram portrays). If you go below 34
degrees or above 40 degrees you can get erratic tumbling behavior.  At
around 38 or 38.5 degrees it can sometimes sit in an old-style flat DT, but
if there is any turbulence it will switch to spiral.  Other models may
behave differently.  The point is that there is no definitive angle for F1A
DT and no clearly predictable DT behavior.  Legislating it would be a
mess.  I am opposed to the use of DT descent time in fly-off, especially
with a short flight of only one minute.  At least with two or three minutes
of flying the effect of the glide and the choice of air are appropriately
important factors in altitude.


No points for a slide
From: Kristine Best

I agree with Pierre, we cannot just slide into acceptance dt flyoffs. No
world cup points should be given if CDs have not followed the FAI rules.

Talk to the Elephant in the corner
From:Stuart Darmon

Hi Roger,
Sorry to bang on again but as Pierre says, if we don’t speak up we’ll end up with these dismal DT flyoffs by default. A few points stand out from the discussion so far.Firstly, there’s nothing in the spirit or letter of the sporting code to prevent a ‘gentleman’s agreement’ among the flyers to DT at a pre-arranged time short of the max. The difference between this and the DT flyoffs we’re talking about is when 1.) this arrangement is imposed on any flyer who doesn’t wish it (even if a majority are in favour) and 2.) when sanctions are imposed by the CD for failiure to DT on time-i.e. when the score recorded may NOT be the duration in seconds of the flight as prescribed by the sporting code. What will happen the first time a ‘sportsman’ simply refuses to DT? Would he be disqualified for following the rules?  Would he be ostracised for making a principled stand against a blatantly illegal practice? A few years ago an attempt was made to impose  DT flyoffs at our Nationals , and all the F1A finallists, myself included, announced that we would do just that. The flyoffs proceded according to the rules and without problems.               The discussion of formalising DT flyoffs and including them in the rules is fraught with danger. First, the shorter the DT, the less representative the outcome will be of what the models ‘would have done’- dedicated models with high climb/ launch altitude at the expense of glide will be needed. Second, a simple gauge to check tail angle is not adequate. For a start, F1A flyers will tell you that on some long models with small tails a few degrees seperates a tumbling descent from spinning on a wingtip. Many of us also use post-DT wing and rudder changes to control the descent- we could kill the spin without touching the tail. And of course some bright spark would pop the wing to compensate, so at the very least you need to regulate the tail angle relative to the wing and the relative incidences of the wing halves; not so simple now, is it?
Finally, as to the alternative of timing by altimetry or GPS, I’m afraid that won’t bring us into the “21st century”. What we always seem ro miss in these long circular debates is that Free Flight is, literally by definition, a restricted technology discipline. It wouldn’t exist at all except for somebody with more wit than we seem to have looking around in the late forties and thinking “This RC is wonderful, cutting edge, sexy, it solves all our problems- but it takes us down a different path and will change the character of the pastime we love. Let’s ban it” Our failure to evolve to meet the pressures of the real world is not because we are dinosaurs but because we refuse to acknowledge that we are. Instead of sticking a band-aid (DT flyoff, altimeter timing) on it, we need to address the root cause of the trouble which is that some-not all-of our models just don’t fit into the places we still have left to fly them.

Cheers, Stuart

Editor’s Comment
To help those who have never seen an elephant on a free flight field.
From the
the elephant in the corner
an embarrassing or awkward topic that everyone is aware of but no one wishes to discuss. An alternative formulation is the elephant in the room