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<DIV><FONT face=Arial size=2>OK, here's the link to a thread I just started on
RCU re. the little tube socket box I mentioned earlier. Use it if you like
the idea, I find that it helps.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2><A
href="http://www.rcuniverse.com/forum/m.asp?m=2514871&mpage=1&key">http://www.rcuniverse.com/forum/m.asp?m=2514871&mpage=1&key</A>=</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Regards</FONT></DIV>
<DIV><FONT face=Arial size=2>Ed</FONT></DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=pattern4u@comcast.net href="mailto:pattern4u@comcast.net">Grow
Pattern</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, January 07, 2005 7:40
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> 2005 Masters maneuver #4 -
Warning</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2><EM>This is a sort of public service
announcement, or at least please regard it as a "Heads-up".</EM></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>For all of you who are flying or will be flying
the Reverse Avalanche you might want to check your wing tubes and phenolic
tube wing supports.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>It seems that if you go into the snap a bit hard
you can bend your wing tube or, in the worst case scenario break, your wing.
The plane is pulling some G's at the bottom of the loop and then you
add more by putting in a lot of elevator to get a good break for the
snap.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Last year I had several incidents reported to me
and my initial reaction was to say that they were probably not flying the
maneuver correctly. <EM>"You need to slow the plane down at the bottom of the
loop",</EM> I said. I must add that what I said did not impress an
FAI and pilot and District masters champion very much. :-(</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So strapping on my asbestos underwear I decided
to do some testing of my own. </FONT><FONT face=Arial size=2>At the end
of November 2004 it was nice here in NJ. I took the Focus-2 and the
Temptation out for a day of Masters 2005. Both planes were inspected for tube
tightness and the wing covering touched up with the glove-iron.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Twelve flights later and an average of 10 reverse
avalanches in each flight I went home thinking all was well. (It got cold and
a bit dark too).</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Back in the shop the first thing that I
noticed was new wrinkles in the covering on the Temptation wings. Nothing
was loose. To test this I put the wing-tube in the wing and leaned on it a
little. All was well but I was beginning to think that the wing must
have flexed to cause the covering to loosen up. A bit like what the
covering sometimes does around the aileron horns. It this case it was at the
roots above the tubes - both sides.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Then I turned to the Focus-2 wings. Not good! The
wing-tube could now be moved up and down and I could hear foamy crunches in
both of the wings. </FONT><FONT face=Arial size=2>Both wings have Carbon tube
wing tubes and it dawned on me that they could not bend (much) or stay bent.
That is why I had not seen this before. The forces were applying
themselves to the ends of the wing tubes. I opened up both panels and added
epoxy and micro balloons to stabilize the sub ribs. It was an easy repair but
could have been a lot worse if I was not looking for it.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I am advised that stress damage is
cumulative and that it does not show up initially. It certainly had
not revealed itself while I had been demonstrating the 2005 schedule over
the late summer of 2004. So where does this leave me? I think we have a
potential problem that requires frequent preventative equipment inspection
depending upon the planes that you fly. If you can slow down your plane and it
is at around 10 lb you may never see this happening.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2><STRONG><U>I would strongly advise checking your
wing with the wing tube in place to look for tube movement. Also look for
straightness if you have an ali-wing-tube.</U></STRONG></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>This situation is a bit unique for me. It is the
first time I have been involved with a maneuver that you don't know you
are doing it wrong unless you fly it that way too many times. And then only if
the wing shows damage or even worse it breaks in the air.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Regards,</FONT></DIV><FONT face=Arial size=2>
<DIV><BR>Eric Henderson.</DIV>
<DIV> </DIV>
<DIV>P.S. The only time I remember seeing a reverse avalanche before is
in the hardly flown? current FAI Finals
schedule.</FONT></DIV></BLOCKQUOTE></BODY></HTML>