physics question about pull ups

On 6/5/2010 2:41 PM, Nine Bravo Ground wrote:
On Jun 5, 2:30 pm, Gary wrote:
On Apr 25, 8:21 am, wrote:

As an aside - the strong G-effect on induced drag is the main reason
why you should try to avoid hardpullupsinto thermals - you give away
a bunch of altitude.

9B

Yes, if you both accelerated and are now pulling up in a constant
velocity of transportation field. But by mentioning the thermal, this
is not likely. With discontinuous fluid fields, coupled pullups and
pushovers which are properly timed within a shifting frame of
reference have the potential to gain much more energy than is ever
lost to induced and friction drag- dry or fully loaded. The fully
loaded case has more potential in typical soaring environments because
more time is available to apply the technique and the events can be
further apart.

For most gliders, the optimized multiplier is so substantial that you
run out of positive g maneuvering envelope (based on JAR standards)
with a mere 2-3 knots of lift.

Best Regards,

Gary Osoba

If you mean dynamic soaring then the airmass velocity gradient needs
to be horizontal, not vertical as is the case with thermals - plus the
magnitude of the gradient in a thermal is way too low to be useful,
even if it were in the correct orientation.

If you aren't referring to dynamic soaring then all I can say is
"huh"?

9B

I don't care what he is referring to. I'm still saying "huh"?
Paul
ZZ