Aircraft tail flutter. This is what it looks like.

[Downunder]

[Deskpilot]

NASTY

 

 

[facthunter]

If it doesn't scare you it should. Nev

 

 

[Guernsey]

It certainly had my heart fluttering.

 

 

[Geoff13]

OK I keep hearing about this. What causes it and what is the solution?

 

 

[ayavner]

looks like it could fly apart at any time! How does it feel, and what would you do about it! The aircraft in question seemed like it was fully under control, what would the pilot have been sensing there?

 

 

[SDQDI]

[SDQDI]

That video will explain it a little.

 

Also a good reason to not exceed VNE

 

 

[facthunter]

I couldn't open the second vid.

 

The faster your plane flys the more you have to try to prevent flutter by designing it properly It's because the structure flexes and there are things like harmonics. The Lockheed Electra airliners lost about 3 aircraft before some one saw one go down because the wing detached due to twisting. Eventually they found the Allison engines were dropping because the engine mounts allowed movement when they deteriorated in service. It was taking less than a second to do this when it starts. The critical speed was not the highest speed it was allowed to fly at.

 

Mass balancing of critical control surfaces is the usual way of dealing with it in our area of aviation, but it can be a bit like a flag flapping. I wouldn't like to see some trim tabs lose their linkages either.

 

Slackness in controls is to be avoided too. Nev

 

 

[rgmwa]

Here's a link to an article written by former Vans Aircraft aeronautical engineer, Ken Krueger, that includes a discussion on flutter, among other things. It's written in the context of RV's, but the principles apply to all aircraft. https://www.vansaircraft.com/pdf/hp_limts.pdf

 

If you can find a copy of the Sept 2014 Kiplanes magazine, there's an excellent article by Barnaby Wainfan, another aeronautical engineer, on Critical Flutter Airspeed. http://www.kitplanes.com/issues/27_3/designers_notebook/Structural_origins_of_flutter_9130-1.html

 

Theodore Von Karmen, who was a famous aerodynamics theoretician once said, "Some fear flutter because they do not understand it, and others fear it because they do."

 

rgmwa