From: Sky2high@aol.com
Message-ID: <e4cf1341.366cbf19@aol.com>
Date: Tue, 8 Dec 1998 00:54:33 EST
To: dechaze@cardell.com, lancair.list@olsusa.com
Subject: Main gear actuator bottom out
Mime-Version: 1.0

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Ed,

I still don't know what condition got the pushrod a bit out of line -- pivot
resistance, wind buffet just before pressure was re-applied, special load from
a hard landing, side landing, too fast of a turn, etc, etc, etc, but it did
not come into contact with the overcenter link wing attach point -- close, but
no contact.

Consider this:  Did you ever tow your tractor out of spring mud utilizing a
long chain between the tractor and a far away tree and by pulling
perpendicularly at the center?  Pulling a few feet moves the tractor a few
inches.  This is a great multiplier of power and works just as well in reverse
if the middle is slightly bent.  Nails go in quite straight until they are hit
a bit obliquely - then they easily bend.

If one assumes something caused the slightest misalignment and the physical
ends of the cylinder and push rod are contrained, the remaining 1/4 inch push
could cause quite a bend.  Considering the unreliability of the 2nd generation
pressure switches, the push may have been at max pump pressure.  Furthermore,
I was able to straighten the push rod by unbending it against my knee (of
course, these were first generation actuators).

In any event, bottomed out push rods can't be pushed any further -- Ergo, they
can't be bent by irrestible forces applied against immoveable objects.

Scott Krueger
N92EX