X-Mozilla-Keys:                                                                                 
Bill Freeman wrote:

Paul,

Just a bit of support for the 10G motor mount spec, which
IMHO should also apply to the gear.  Both see their most
severe load condition during a hard landing.

I landed my Long EZ about 6-7 years ago, after about
250 hrs of flying it and *just* after a very nice squeaker
mains touchdown (EZ is easy this way) a very unusual
and strong gust literally slapped the nose down onto
the runway.  I was shocked at the severity!  Gayle
expressed surprise and concern and "what was that?!"
from the back seat.

It was rolling along just fine, so I taxied back and
upon inspection the nosegear hardware had been
severely overloaded.  The Long EZ has a 1/8" 2024T3
aluminum plate in front of the fiberglass strut and
an aluminum casting behind it, with two bolts on each
side clamping the nosegear onto the strut, plus epoxy
flox bonding, too.
The plate was bent about 1/4" on each side and the AN3
bolts were severely deformed, with the heads at about
a 20 deg angle from the normal 90 degs!  I straightened
the aluminum plate, drilled everything up to 1/4 and put
AN4 bolts to attach the nosegear to the strut, have had
no more problems, but no gusts that severe at touchdown,
either.

I would guess around 6-8 times the normal peak load
was applied to the nosegear by that gust.  It is rare, but
the same sort of thing can happen again  and you may not
be lucky enought to have just rolled on the mains. I wonder
what would have happened if the gust had hit while I was
still 3 ft in the air!!

Bill

I wonder what people are going to call me when I ask
them to pick up a 3000 pound car with thier motor mount
using the fuselage as a lever???? :-)

Vance has some recent expierence along these lines.
What do you think about all this Vance?
 
Paul Lamar
 
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