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ACRO E-mail Archive Thread: [Acro] RE: Aileron Flutter Question

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ACRO E-mail Archive Thread: [Acro] RE: Aileron Flutter Question


Thread: [Acro] RE: Aileron Flutter Question

Message: [Acro] RE: Aileron Flutter Question

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From: "Peter Ashwood-Smith" <petera at>

Date: Thu, 31 Oct 2002 15:23:44 UTC


You  make both flutter resistant with proper static balance. Normally you
would put weight in the leading edge ahead of the hinge point in a Friese to
obtain the proper static balance. If the hinge point is not aft of the
leading edge, you would add a counter balance in the form of a horn (i.e the
surface is L shaped). Alternatively you can add mass under and ahead of the
surface hinge line with a streamlined tube of some kind angled 45 degrees or
more forward, this is often combined with a spade.

Other tricks that can reduce flutter are reduced hinge gap. With an offset
hinge you can make a beautifully tight hinge gap. I.e. the cross section of
the trailing edge '(', leading edge of the aileron '(' and hinge axis 'o'
look like this: "((  o ". 

Anyway you don't want to be mucking with this stuff unless you know what you
are doing because flutter can rip a plane apart in milliseconds.


	-----Original Message-----
	From:	Eric Minnis [SMTP:acroeric at]
	Sent:	Tuesday, October 29, 2002 9:56 PM
	To:	acro at
	Subject:	[Acro] Aileron Flutter Question

	Anyone know which aileron design is more flutter resistant? Frise or
	Eric Minnis
	Swick Tcraft 
Attachement 1: part2.html


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