My GOD !!! If <THAT> doesn't hold it, I don't know WHAT would !!!
Looks like a piece of railroad bridge is missing !!! :-) :-)
Thanks !!
....bobp
------------------------------orig.-----------------------------------
At 08:01 PM 8/25/00 +1200, you wrote:
a few problems with load dissipation into the fuse with the spring gear, allJust a few thoughts to go with the photos that mike has made available.
Those that have been following this forum for a while will know I have had
that is in the archives.
braking loads have been causing stress on the lower door post area ( notI use my Rebel on rough strips very frequently and it became obvious that
only braking loads but pot holes and rocks etc.)
to transfer these loads from the carrythrough to the lower door post ( youI am also very concerned that the wing strut attach bracket is being used
cant rely on the 'sandwich' of the cabin floor ( SG14 & SG 13 etc.) to
dissipate these loads, this a very inefficient method, I beefed this area up
and it made no difference!) If you get someone to sit in the aircraft and
apply the brakes and get someone else to push backward and forward on the
prop simulating braking loads, you can feel the wing strut attach bracket
flexing backwards and forwards. ( You can measure this by clamping a piece
of angle on top of the gear leg facing back along the side of the fuse, then
measure the amount of deflection as you rock back and forward.) If this
happens long enough and often enough, over time stress points will appear in
these brackets. Not a good place to get cracks! ( I am really fond of those
wings staying in a consant angle relative to the fuse!!)
the bungee gear would attach at the rear. I made up an I beam out of goodTo counter this I placed a hard point on either side at the position where
quality steel and attached this to the straddle brackets on the gear ( by
putting in longer bolts)and to the hard point at the rear.
have been flying it for about three months so far and the system seemsThis completely isolates these twisting loads before they enter the fuse, I
bullet proof.( so far!)
If you did not intend to operate in less than ideal places this mod may notI will issue my usual disclaimer! I do operate on rough strips regularly.
be necessary. This is the type of mod that if I decided to sell my aircraft
( I couldn't think why I should!) I would unbolt it ( about an hours work )
and put the fairings back on, I would place the I beams in the luggage
compartment and say to the new owner if he intends to operate in less than
ideal places he should consider bolting them on.
and sweep the Hangar floor!!Hope this gives food for thought, no sense everybody reinventing the wheel.
Cheers
Alister
PS Looking at the photo of my Rebel I think I had better give it a clean
mike<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META content="text/html; charset=iso-8859-1" http-equiv=Content-Type>
<META content="MSHTML 5.00.2614.3500" name=GENERATOR>
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<DIV><FONT face=Arial size=2>Just a few thoughts to go with the photos that
andhas made available.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Those that have been following this forum for a
while will know I have had a few problems with load dissipation into the fuse
with the spring gear, all that is in the archives.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I use my Rebel on rough strips very frequently
doorit became obvious that braking loads have been causing stress on the lower
attachpost area ( not only braking loads but pot holes and rocks etc.)</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I am also very concerned that the wing strut
lowerbracket is being used to transfer these loads from the carrythrough to the
beefeddoor post ( you cant rely on the 'sandwich' of the cabin floor ( SG14 & SG
13 etc.) to dissipate these loads, this a very inefficient method, I
forwardthis area up and it made no difference!) If you get someone to sit in the
aircraft and apply the brakes and get someone else to push backward and
bracketon the prop simulating braking loads, you can feel the wing strut attach
months soflexing backwards and forwards. ( You can measure this by clamping a piece of
angle on top of the gear leg facing back along the side of the fuse, then
measure the amount of deflection as you rock back and forward.) If
this happens long enough and often enough, over time stress points will appear
in these brackets. Not a good place to get cracks! ( I am really fond of
those wings staying in a consant angle relative to the fuse!!)
</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>To counter this I placed a hard point on either
side at the position where the bungee gear would attach at the rear. I made up
an I beam out of good quality steel and attached this to the straddle brackets
on the gear ( by putting in longer bolts)and to the hard point at the rear.
</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>This completely isolates these twisting loads
before they enter the fuse, I have been flying it for about three
idealfar and the system seems bullet proof.( so far!)</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I will issue my usual disclaimer! I do operate on
rough strips regularly. If you did not intend to operate in less than
decidedplaces this mod may not be necessary. This is the type of mod that if I
aboutto sell my aircraft ( I couldn't think why I should!) I would unbolt it (
intends toan hours work ) and put the fairings back on, I would place the I beams in
the luggage compartment and say to the new owner if he
think Ioperate in less than ideal places he should consider bolting them
on. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Hope this gives food for thought, no sense
everybody reinventing the wheel.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Cheers</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Alister</FONT> </DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>PS Looking at the photo of my Rebel I
*-----------------------------------------------------------------------------------*had better give it a clean and sweep the Hangar floor!! </FONT></DIV>
<DIV><FONT face=Arial size=2> </FONT></DIV></BODY></HTML>
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