Here’s a note from Lon Kelley regarding
his ES motor mount issues. I hope these pictures will encourage you all to
examine closely … very closely … your motor mount. Personally I don’t
see how there wasn’t a very serious accident because of this problem …
Lon and Pam were just plain lucky.
Jim Nordin
From: PKkelle@aol.com
[mailto:PKkelle@aol.com]
Sent: Saturday, August 25, 2007
3:40 PM
To: panelmaker@earthlink.net
Subject: ES engine mount
Jim, here is some information on the recently discovered engine mount
problems in my ES. The pictures are attached and show some major breaks and
widespread cracking in the welds. It is my opinion that these cracks indicate
improper welding procedures in my mount, and there may also be a problem in
other early ES mounts. I have not got any professional opinion on the welds,
and really don't intend to, but the cracks all appear to be in the
heat-affected zone adjacent to the weld, and this is the area of concern in
most high carbon material where embrittlement might occur.
I believe these cracks have been there for a long time, and we missed
them during inspections. My only excuse for this is that they wouldn't be
visible under the paint. What led to my finding them was some very rough
taxiing at Sun N Fun, Oshkosh and a rough grass strip this summer. At the last
oil change I specifically wanted to look at the nose-gear mount, and feel very
lucky that we took the bottom cowling off, and I stuck my nose down there and
chipped some paint back. Of course the two broken members were pretty obvious
if you were looking. My plane has 1225 hours and this mount was made in 1994.
Incidentally, we sent our strut back to Lancair in about 1999, and Vern
rebuilt it. We have not experienced serious shimmy with it, and I don’t
believe the weld cracks are associated with shimmy. Lon Kelley