Date: Wed, 9 Dec 1998 19:45:13 -0500
From: Marvin Kaye <74740.231@compuserve.com>
Subject: Main Gear Actuator Bottom Out
Sender: Marvin Kaye <74740.231@compuserve.com>
To: Lancair Mail List <lancair.list@olsusa.com>
Message-ID: <199812091949_MC2-6305-28EB@compuserve.com>
Mime-Version: 1.0

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From:  Sky2high@aol.com >INTERNET:Sky2high@aol.com
Subj:  Main Gear Actuator Bottom Out

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