This video shows a Hawker jet with the wing fluttering up and down like it's about to break. What can cause flutter like that? Can it actually cause a wing or stabilizer failure? How can flutter be prevented? What should be done if something like this happens?
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2The description on https://www.youtube.com/watch?v=s3-g9B6Fgjs is not too bad. Usually the only way to stop flutter without breaking anything is to slow/brake down really quickly. I also like https://www.youtube.com/watch?v=RenbFgLZBNA, plus there is the linked PDF. – yankeekilo Dec 22 '13 at 08:15
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In the case of that Hawker we definitely seem to be looking at a resonant vibration in the wing (think the Tacoma Narrows Bridge, but flying), likely due to some "incorrect" maintenance done on the plane at some point. The FAA SAIB linked in the video description (NM-14-05) is worth a read, though it doesn't really answer your question. – voretaq7 Dec 22 '13 at 08:53
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1@voretaq7 - your comment would make a terrific answer. Flutter is all about resonant vibration, & one of the reasons we have Vne – Dan Pichelman Dec 22 '13 at 15:31
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I guess altitude and winglets are factors. http://www.ainonline.com/aviation-news/ainalerts/2013-05-09/bulletin-advises-fl340-limit-api-wingletted-hawkers – xpda Dec 22 '13 at 17:24
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Imbalanced or loose (and, in extreme cases, structurally weak) control surfaces can cause flutter, a type of harmonic motion. Flutter is a very dangerous condition; if it is not stopped, it can cause structural failure and potentially lead to a fatal accident. V-tail Bonanzas had a series of such accidents related to flutter of the butterfly ruddervator tail.
I understand that prevention is a combination of good maintenance and keeping the aircraft below Vne (never exceed speed), or possibly other speeds in some configurations.
The appropriate reaction would be to slow down, first and foremost. Descending is probably also a wise choice.
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6Poor maintenance can definitely be a cause of aileron flutter in light aircraft (worn aileron rod end bearings that allow enough play for resonant vibrations to set up are a pretty classic example, and part of why we check the ailerons for free play during preflight). – voretaq7 Dec 22 '13 at 08:46
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Flutter is essentially an aerodynamic and structural interaction that has gone unstable. At certain speeds and flight conditions, the aero forces interact with the structural dynamics of the aircraft. This aero and structural dynamic instability can be seen in other places other than aircraft as well, the most famous that comes to mind is the one with the bridge rocking back and forth before collapsing
