budyerly@msn.com wrote:
> Yep Graham,
> Airplanes only feel air pressure, not the velocity of the molecule alone.
> Dynamic
pressure is Density times Velocity Squared or IAS (actually you have
calibrated then equivalent) is what the airplane feels. Those RV guys got all
hung up on this and confused everyone.
>
> Bottom line, what you read on the airspeed indicator counts.
Hi Bud, scenario: flying at 10,000 with standard pressure and temperature with
IAS of 165kts the TAS calculates to be 190kts. Are you saying that is OK?
Currently I feel not. Im always open to (non technical!) well reasoned
persuasion
and argument but even despite Ivanss welcoming and comforting story about
the flutter trials I would have thought this puts one into unknown territory.
Agreed that structural issues are related to IAS but I feel that specifically,
flutter issues relate to the actual speed with which particles pass by!
HOWEVER - if the design and testing criteria is that the VNE is based on IAS and
that flutter is proven not to occur at any TAS that could concievably be reached
at that maximum IAS then I guess that my thinking about VNE (whilst
conservative)
has been wrong!
My opinion was from my gliding days where in mountain wave conditions we could
get very high, circa 25,000. Sometimes we would descend afterwards from high
altitude at high speed to lose height; with VNE of 135kts common in gliders the
TAS could be extremely high - up to 200kts! Im sure I can remember some gliders
flight manuals warning of this and that VNE was TAS based - but it was a
long time ago!
Graham - thanks for that. Mass sounds better! I said I was at schoolboy
level.
But a schoolboy would have known that so I am below that level even! I was
referring to the amount or number of molecules and yes, mass is better than
volume!
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G-TERN
Classic Mono
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