Fantastic. Two great posts, from 59er and from Mr.
Cochrane. I am starting to lean towards the idea of
a 500ft or 1000ft finish.
My remaining question is still whether safety is best
served by the idea of a narrow cylinder, remote 'control
point' at 500-1000ft, or the standard 500-1000ft cylinder
over the airport.
I do think that low passes AFTER the finish as a crowd-pleaser
are at contest organizer discretion, but I don't think
these should be encouraged by extra contest points.
Forgive me for this, but
there is one perhaps morbid and a little tasteless
observation about an advantage of low passes. The
finishers who were dehydrated ended up stall/spinning
somewhere near the airport that was likely unoccupied,
instead of a half-uncoscious landing and swerving off
into the poor spectators lining the runway.
I have been in a situation with a problem aircraft
where I purposely decided to fly over an ocean so that
if anything went wrong further, I wouldn't hurt people
on the ground. So I do take this seriously.
I wonder if we will now see less of these stall/spin
accidents and more of the final approach landing accidents
instead, just shifting the problem.
Well, since by far the most common victim is the pilot,
and survivability seems much better with a miffed landing
than a stall/spin, we're all maybe still better off
with 500-1000ft finish altitudes and miffed landings
instead.
I'll get to watch all this in the coming contest, and
I'm sure I'll see at least a few dehydrated pilots
do 'interesting' things. Hopefully not TOO interesting...
Hmmm...perhaps Alhambra or Evian would be a good contest
sponsor?
At 16:00 27 March 2005, Bb wrote:
M B wrote:
It occurs to me that if someone is on final glide
at
the end of a competition, they may pick a speed (like
85 knots) which their computer says is optimal for
points, but which is both:
1) too fast for a rolling finish/landing
and
2) too slow for a pull up, turn around, and landing.
Is that an accurate assessment? Would a competition
pilot be put in a situation where he must decide between
points and safety of the landing?
This is exactly right. The mathematically optimal point
score comes
when you cross the finish (50 feet, middle of the airport)
at the
regular inter-thermal glide speed, 70-80 kts rather
than 130. This is
of course about the worst place from which to start
a sensible pattern,
especially when 50 other guys are doing the same thing
at the same
time. You see fast finishes because most of us are
a bit chicken and
hold some reserve, losing a few points in the process.
Everyone in these threads has been advocating 'just
do a rolling finish
if it seems touchy' but that's a hard decision too.
The finish gate is
typically downwind, so the following pattern is only
a 180 to land into
the wind. Thus, a rolling finish is a downwind landing,
often in a
substantial wind, with a huge fleet landing in the
opposite direction.
Furthermore the pilot in the typical marginal situation,
with enough
energy to cross the gate at 50-100 feet with 70-80
kts, has to
dissipate a lot of energy to roll a finish at the far
end of the
runway. If not, this pilot would cross the runway threshold
at say
100-200 feet and 80 kts. At this point it's really
too late to roll
(remember all those guys landing into the wind at the
other end of the
runway!) and you don't have enough energy to do a proper
flying finish.
Coffin corner.
So the decision to roll - accept a downwind landing
into the face of
traffic - has to be made at least a mile or two out,
while there is
still substantial energy left and a good chance of
picking up 50-100
feet of energy, or misjudging your total energy by
50-100 feet. I think
I can start to sympathize with people who get in this
mess.
John Cochrane
BB
Mark J. Boyd