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Old July 7th 07, 09:46 PM posted to rec.aviation.homebuilt
Peter Dohm
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Posts: 1,754
Default Survivability VS landing speed

"Vaughn Simon" wrote in message
...

wrote in message
ups.com...

Thanks in advance for the help


I can't help you on the specific article (I would like to see it

myself).
Remember that Energy = MV^2, and the landing ain't over until all of that

energy
has somehow been dissipated. It can be dissipated in aerodynamic drag,

rolling
resistance, and by heating up brakes; or it can be dissipated by deforming

the
airframe and its occupants. We naturally prefer the former.

Assume any weight you like for your airframe and do the math for

different
speeds. You will quickly discover that ten knots one way or the other

makes a
heluva difference. A lighter airframe also makes a significant

difference.

This is why the Sport Pilot regulations limit both gross weight and

stall
speed... to limit the landing energy the pilot must deal with.

Vaughn

Presuming, of course, that the plan is to crash--which has been one of my
biggest criticisms of both Ultralight Vehicles and LSA from the beginning.

OTOH, other things being equal, higher landing speed also equates to greated
crosswind capability. Given excellent pilot proficiency, 10 knots change in
landing speed means up to 4 knots change in maximum crosswind
component--which is also a heluva difference!

Peter