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In a message dated 6/27/99 9:58:25 PM, you wrote:

<<Instead of using the 1/4" holes I made at the cockpit closeout rib location,
I'm planning to use the holes at the wing tiedown points for jacking the plane
off its gear. Have any of you tried this with success? Is there a reason why
this should not be done?>>

Two possible problems, neither of which may be harmful:

1)  You would have to make sure that the wing root bending moment is not too
high.  The wing design limit load in flight (6 G's times the gross weight) is
distributed along the wing.  The concentrated load out at the wingtip would
result in a higher bending moment per pound of load, but with a smaller load,
of course.  I gotta think that it would be less than a 6 G flight load -- but
I have not run the numbers.

2)  If you're building the plane, and the wings are off, you'd need another
way to lift the plane.

Having said that, I agree that the per-plans jacking points are rather close
inboard.  I once stood on the wing spar out near the BL-50 rib (climbing into
my project) and caused the plane to lift off it's jack point on the other
side.  (No damage was done -- the pin dropped back into the hole.)  My
fuselage is very light now (there's almost nothing in it yet) so that won't
be a problem too much longer.  Now I have a small stepladder near the wing
root so I don't have to climb on the spar.  I use the A-frame jackstand that
was in the LNN newsletter about four years ago -- It works great!

- Rob Wolf
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