Interesting discussion.

Some time ago, a well known and very good hang gliding pilot, Mark
"Hollywood" Champlin (sp?), started flying rigid wings. To familiarize
himself with the different behaviour (it is almost impossible to spin
a HG), he did some "safety training". When recovering from a spin the
wing collapsed and he fell to his death.

The cause was that he exceeded Vne and then pulled up.
The problem is that (at least it was told at the time :-)), rigid wing
pilots are taught about Vne and to not build up too much speed in a
dive from the start of their training.

In a HG, this problem is almost non existant. In a HG in a "bump at
high speed" situation, either from manual input or a gust, the
flexible wing uses its elasticity to sort of "circumvent the forces".

For example (I have not read this -  I hope it is correct):
A plane or HG flies along very fast, but with little AOA.
A gust from below doubles the AOA. Since, AFAIK, in this regime the
lift is fairly linear, the airplane would have 2 g. The HG would flex,
reducing the wing are slightly. The tunnel would became greater (the
trailing part of the wing would swing up in regard to the fixed
leading edge), reducing AOA. The wing would get less effective.
Through all this, the lift would not increase by a factor of 2. 

Also, flex wings are surprisingly robust, even slow beginner
nice-weather-only gliders are specified to +6 gs.

So, the Vne problem is almost non existant in HGs and this pilot was
not used to watch out for it and how fast a seemingly harmless
situation can get bad because of the increasing speed.

Regarding the Airbus, IMHO you should not be able to break an airliner
through rudder input, especially at those speeds. OTOH, I have seen a
video of a NA Bronco on purpose flying into the vortices of an
airliner (IIRC 707) and know the huge forces that can occur, even at
some distance after the airliner generating the vortices.


Bye bye,
Wolfram.

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