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Re: Europa-List: More on VNE

Subject: Re: Europa-List: More on VNE
From: Gilles Thesee <Gilles.Thesee@acgrenoble.fr>
Date: Mon, 24 Sep 2007 03:09:46

Andrew Sarangan a crit :
>
>
> I read the Vne definition from wikipedia (which you posted) and your
> observations that Vne is always given in IAS, and am having a difficult
> time reconciling the two. 

Andrew and all,

As you say things are not that straightforward.
Airplanes are designed for a specific Vd (Velocity dive) which is 
expected to be well below flutter velocity.
Test pilots must *demonstrate* Vdf where flutter is absent (Vdf < or = Vd).
After that, Vne is *calculated* to be Vne < or = 0.9 Vdf  < or = Vd. 
This takes into account any ASI inaccuracy with a reasonable safety margin.
Only test pilots are allowed to intentionnally exceed Vne up to Vd.

So provided the airplane is correctly rigged and control-balanced, there 
is no problem flying up to Vne in calm air.
Be aware though, that there is also a Vno and a Va (maneuvering speed) 
to comply with. At Va you are only allowed to actuate *one* control to 
full deflection at a time.

FWIW,
Best regards,
-- 
Gilles
http://contrails.free.fr



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