On Sep 26, 8:33*am, John Cochrane
wrote:
To give a simplistic/extreme example. * We have a guy in our club who
flies a 1-26. *For a while, he also owned an ASW-20. * When he owned
the 20, he was always in the top 5 in both handicapped and
unhandicapped contests. *He also routinely wins the 1-26 Nationals.
Now, put him in a 1-26 (with it's 1.6 handicap) flying against an
ASG-29, and he's likely to finish near the bottom of that contest if
there is even one weak day. * Given that many of our nationals are
decided with only 4 or 5 days of flying, that makes it pretty unlikely
that a great pilot would be rewarded by flying the 1-26.

While that's probably the extreme example, it's useful for
illustrating the point. * You have to draw a line somewhere in terms
of "bunching" ships into a handicapped class that's close enough to
eliminate the majority of the luck factor involved in having the right
ship for the conditions. * For better or worse, the IGC has already
drawn that line, so why reinvent it?

I think there is a bit of a misconception here. You need to focus on
the whole contest, not just the particular day. The handicaps not only
try to compensate for speed differences on a consistent day, they also
try to compensate for the impossible days, and are pretty succcessful
at it. The high performance gliders have handicaps that are way too
punitive based on their polars. That is to compensate for their
greater chance of making it home, as well as a little bit of
affirmative action.

On (say) 1 out of 5 days, the 1-26 can't cross the blue hole, gap,
etc. and lands out and the asg 29 wins. On (say) 1 out of 5 days, the
1-26 gets to play on the local ridge / stay in the cloudstreet etc.
while the asg29 has to go cross some horrendous blue hole; the asg 29
finishes but with a terrible score. On (say) 3 out of 5 days, both
pilots make it home in consistent weather, but the 1-26 handicap is so
huge that it comes out ahead by 50 points or so. (This is pretty much
the story of the last sports nationals I competed in, substitute "KA6"
for "1-26" and "ASW27" for "ASG29")

Over a long contest, the two gliders even out if piloted equally well.
The issue is variance, not mean (yes, we are techies, are we not) A
contest with more consistent days favors the 1-26; a contest with more
weak days favors the ASG29, a contest with more days/tasks that allow
the 1-26 to stay in small areas of good weather favor it again.

Thus the real problem with a wide handicap range is not that one or
another kind of glider is favored on average, it is that there is even
more weather and task related luck than usual. Dave Stephenson did
great in sports class in Foka, Ka-6 and associated gliders, proving
those can compete. In part this was great piloting, in part it was a
bet on consistent weather.

Splittiing gliders up into narrower handicap ranges will certainly
produce races with less luck. On the other hand, it also produces
smaller contests. I'm dismayed that the average regional seems to have
7 gliders per class, and the average national seems to be struggling
to keep in the two digits.

If we had enough gliders, I'd be all for *three classes -- "FAI" for
handicaps above 0.90 or so, "club" for the middle range, and "ex-word-
class" for handicaps below 1.0 or so. Spitting only in two by taking
out the middle -- "club" for 15 gliders in the mid range, and then
"sports" that keeps only the Nimbus 3 and 1-26, is not a good idea.
But we need more gliders....

John Cochrane

Exactly.

Here is a specific, real example.

Pilot A and Pilot B competed in four contests at the same site over
four consecutive years. 18 of the contest days they flew against each
other in an FAI class. For 9 of the days they competed in Sport Class
and Pilot B flew a Club Class glider with a 14% higher handicap.

Over the 18 days of FAI class flying Pilot B's average daily score was
97% of Pilot A's.

Over the 9 days of Sports Class flying Pilot A finished every day and
Pilot B landed out twice. If you count every contest day (including
the two landouts) Pilot B's average daily score was 95% of Pilot A's.

If you drop the scores for both pilots on one of the days that Pilot
B's landed out, Pilot B's average daily score was 99% of Pilot A's.

If you drop the scores for both pilots on both of the days that Pilot
B's landed out, Pilot B's score was 107% of Pilot A's.

This is consistent with John's contention that handicaps are
calculated inclusive of a presumed higher landout rate for gliders
with higher handicaps. I know that two pilots over 27 contest days
doesn't make a statistically significant sample, but it gives you a
sense for the scoring effects at work. As John said, any contest with
landouts increases the variance of outcomes, even without handicaps.

It makes me realize that the Drop-a-Day provision that has been
suggested would tend to favor higher handicap gliders.

9B