Avoiding Vne

Edward Downham wrote:

It is important to note that this margin is there to cope with things such as
ASI position and calibration errors. When you fly a glider at an _indicated_
speed of Vne, you might actually be nearer Vd and the realm of the test pilot.

No. VNE is an indicated airspeed limit (IAS). If there is a airspeed
calibration error, VNE has been reduced to correct it. The margin is
there for instrumental errors, and *pilot* errors.


As Bill Dean has mentioned, some gliders lose a lot of their control authority
over Vd. You may find yourself flying faster and faster and unable to do much
about it. Also, the faster you get, the more likely you are to overstress the
airframe with control inputs (and I don't just mean the elevator).

Have you any reference for this affirmation ? THis is a know issue on
earlier delta wings, also in earlier near-transsonic aircraft, but I
don't know any glider with such a problem.

In most modern gliders you should be able to pull 6g+ without breaking any bits
off them.

Not at VNE !!!

The rise is drag is high, and will pretty certainly arrest any
further speed build-up and bring the nose up quite smartly. Also you won't get
so close to the ground, if this is a factor.

The drag rise is not enough to avoid overspeeds. The rise in drag
provided by *airbrakes* (not pulling too hard) is the *only* way to
avoid either flutter (above VNE) or breaking the wings (by overloading).

Except when too close to the ground this is always the only thing to do.

And to come back to the original question, I think there is nothing to
fear pulling the airbrakes before getting out of the spin, since it will
help stopping the rotation (the outer airbrake will have a greater drag
due to greater airspeed)

--
Denis

R. Parce que ça rompt le cours normal de la conversation !!!
Q. Pourquoi ne faut-il pas répondre au-dessus de la question ?