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Old 25th Feb 2005, 09:32
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Genghis the Engineer
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Roger "Dodge" Bailey gave a talk a year or so ago in Oxford where he recounted how low the lateral and directional stability of the Sea Hurricane where in his opinion. He then described an argument with a former wartime Hurricane pilot who maintained that the aircraft was an incredibly stable gun platform and Roger didn't know what he was talking about.

Dodge's conclusion was of-course that neutral static stability in certain axes (particularly lateral and directional) can imply less gust response - particularly to lateral gusts. And therefore what is technically a less stable aeroplane, can appear more stable to the operator.

All down to terminology and how you use it really, as Lomcevak says, the term "stability" on it's own is incredibly amibuous and can mean any of about a dozen things.


Similarly, I once made myself unpopular by declining to allow somebody to do a mod to an aircraft with high directional static stability, that was intended to increase that stability. My argument was that it was likely to make the aircraft directionally uncontrollable in side-gusts. Well, since when he ignored me and did it anyway, he went off the side of the runway and wrecked the aircraft, I was probably right. But, his perception was that the aircraft was directionally unstable, because of lateral excursions when flying in turbulence - the reverse was actually true, he had too much directional stability. Some people (especially light aircraft owners I think sometimes) just won't listen, and as a result an aircraft was written off, although thankfully nobody hurt.

G

Last edited by Genghis the Engineer; 25th Feb 2005 at 09:55.
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