Duncan & Ami McFadyean a crit :
> <ami@mcfadyean.freeserve.co.uk>
>
> Not forgetting that I=mr2, counterbalance weights in the tailplane
> leadng edge, apart from being much heavier would have much less
> inertia, offering a lower amount of resistance to flutter and/or its
> initiation.
Duncan,
The leading edge balance weight is something widespread in aviation.
Concerning weight, some messages seem to state that some Europas do
carry weight in the tail.
Defeating flutter necessitates a complex study, but mass balancing has
something to do with the POSITION of the CG of the control surface. It
is considered that one should aim at a forward or at least neutral CG
position with regard to the control hinge.
A lightweight construction aft of the hinge point is key, and painting
and hardware are best carefully studied to avoid adding weight aft of
the hinge.
The problem with mass balance arms (which are also used), is localized
wear and tear allowing slop to develop. Any slop encourages flutter.
Of course flutter also has to do with torsional and flexural(?)
properties of the structure.
Darrol Stinton's Design of the aeroplane could be a good starting point
for further insight.
FWIW,
Best regards,
--
Gilles
http://contrails.free.fr
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