I does make a difference - 25 knots could bias the
apparent energy by 250'. So you would either have to
estimate wind from the traces based on thermal drift,
and/or make it part of the CD's discretion.

You are correct that a tailwind both raises the apparent
energy as measured by GPS and reduces the altitude
you need to get home, the first effect is bigger than
the first so they don't totally offset.

9B

At 03:30 06 October 2003, Bruce Hoult wrote:
In article ,
Andy Blackburn wrote:

What if, in instances where we are using a 1 mile
cylinder
for the finish, instead of putting in a hard deck
of
500', we make it so the scoring program can calculate
TOTAL ENERGY for each glider at the one mile point
(this should be relatively easy to do). The idea would
be for each sailplane to have at least 500' of EQUIVALENT
ALTITUDE at 1 mile. That is, take actual AGL altitude
and add the equivalent altitude that the glider would
have if it's kinetic energy were converted to altitude
(at say 60 knots).

I agree with the idea, but the fly in the ointment
is wind -- the
analysis computer won't know what the wind is, so it
can only know your
groundspeed not your airspeed. It will thus let you
get away with a
lower airspeed if you're going downwind, while you'll
need a higher
airspeed to satisfy it if you're going upwind.

Fortunately, these errors are in the sensible direction,
but the
magnitudes of them may or may not be sensible.

-- Bruce