[Florin_Andrei]

(asking here because your other reply is nested too deeply)

> The margin between stall and overspeed is something like 20 knots at that altitude.

Whaaa? I thought aircraft have a much wider margin.

How does it change with altitude?

If the margin is so low, then wouldn't a sudden wind gust simply knock the plane off the sky?

[jrockway]

http://en.wikipedia.org/wiki/Coffin_corner_%28aviation%29

(Perhaps a better explanation than the article: http://de.wikipedia.org/wiki/Datei:CoffinCorner.png)

And to answer your question about wind gusts: yes. That is why you don't fly into thunderstorms.