Rudder counterbalance ?

Wayne Galligan wgalligan at goodsonacura.com
Thu Apr 28 10:25:53 AKDT 2005


I have had conversations with a few people that own these airframes
(Impact)and they along with a few others have strengthened the fuse in two
ways.  A ladder  type frame in the fuse from the wing t.e back to the stab
area and another put a stiffener(former) at the front of the wing area to
decrease the possibility of compression of the fuse in this area.  It is
believed that compression of the fuse in this area contributes to a wave
progression all the way back to the tail section.  The tail section being
the smallest and weakest area gets whipped and eventually the fuse breaks or
contributes to tail feather flutters.

>From what I've heard....  FWIW

WG


----- Original Message ----- 
From: "Peter Pennisi" <pentagon.systems at bigpond.com>
To: <discussion at nsrca.org>
Sent: Thursday, April 28, 2005 4:29 AM
Subject: Rudder counterbalance ?


>
>
> Hi all,
>
>
> Most of you would be aware that a number of Composite ARF "IMPACT" have
> failed from suspected rudder flutter.
>
>
> I raise a couple of questions to this forum;
>
>
> I know that the purposes of counterbalances are to reduce the loads on
> servos and linkages in our application but what are the side effects.
>
> Can a rudder counterbalance create undesired torsional stresses on the
> fuselage?
>
> Can a poorly configured and tensioned pull-pull linkage to the rudder be
> more susceptible to flutter if the rudder has a counterbalance?
>
> What other types of forces are at play with counterbalances?
>
> I am just trying to find a reason for the relatively high failure rates
> against this design.
>
> It is the same old thing- why are some people having problems and others
> don't. (Similar story to 4-stroke exhaust headers)
>
> I will be test flying my model soon so I am obviously concerned.
>
> Regards,
>
> Peter
>
>
>
> =================================================
> To access the email archives for this list, go to
> http://lists.f3a.us/pipermail/nsrca-discussion/
> To be removed from this list, go to http://www.nsrca.org/discussionA.htm
> and follow the instructions.
>
> List members email returned for mailbox full will be removed from the
list.
>
>


=================================================
To access the email archives for this list, go to
http://lists.f3a.us/pipermail/nsrca-discussion/
To be removed from this list, go to http://www.nsrca.org/discussionA.htm
and follow the instructions.

List members email returned for mailbox full will be removed from the list.



More information about the NSRCA-discussion mailing list