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<< Lancair Builders' Mail List >>
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Of course, any good Lancair discussion requires a story with a moral -- This
is no exception. Pull your chairs near to the wood stove and listen up!
I started building in 1989 and therefore, received an early version of the
ESCO strut. Serial No. 30 to be exact. Thru the many years of building, I
religiously executed all the service bulletins -- From memory (old people
only remember history), I applied Locktite to the screw-on flange and later,
sent in my strut for a more complex internal service which resulted in it
becoming serial number 30A.
Finally finishing N92EX (1996, I am a sloooow builder), I recently flew to
S&F and mentioned theoil oozing from under the flange. Lancair expertise
indicated it was an internal leak, possibly serious, and I should return the
strut for service. Upon returning home (nice flight, red carpet in Gadsden
AL) I thought I would send in the strut and also request the "centering"
upgrade since I had the usual scrape marks on the door caused by the
occasional, slightly off-center, retraction of the nose gear.
The strut was returned within a week with the centering upgrade complete,
including a beefier ram and a much beefier flange with a locking collar.
Conversation with Lancair indicated that the leak, resulting in low oil, may
have lead to the apparent trashing of the internal mechanism -- I was lucky
to have sent in the strut before a complete failure had occurred. Good.
However, the new collar interfered with the Lancair towbar attachment, but it
was suggested that the pin/bracket be placed below the fork when everything
was bolted up.
So Far, So Good!
After a few flights, I found oil on the nose wheel center tread. Further
investigation revealed a leak from the ram seal and the strut had sunk 1/2
inch lower. Conversation with the strut rebuilder indicated that he had done
50 with no leak, but the seal installation, requiring the seal be streched
over some parts, was difficult and I should return the strut to have the
problem fixed. I did just that.
Today, (Yes, Mid April to Mid June - No fun Lancair flying -- I couldn't find
anybody to hold up the nose while I taxied) I installed the "re-sealed" strut
and noted that the collar (firmly fixed by a hex-head bolt) was quite loose.
A call to Lancair Management (Quality Control?) concerning the danger of
sending out struts in that condition resulted in a call back from the strut
rebuilder with the following comment -- We send them back loose so that the
builder can set the wheel to track straight and then tighten the flange
lock...(Indeed, this is a two-piece affair with slotted holes in one part).
"WELL!" I said, "I had no such information on the first install and I flew it
a few times that way (It was snugged enough to not appear loose)." The reply
was "I should write up instructions on that".
Further thought had me consider that perhaps, possibly, I should commit
myself to the local loony bin.
Consider the following:
First -- The self-centering mechanism only operates when the strut is fully
extended (a pin entering an inverted v slot?) so that when the gear is
retracted, the wheel is straight and will not bang its way into the well.
Second -- When the strut is compressed, there is a mechanism to dampen twist
of the nose wheel, but no centering mechanism other than rolling in a
straight line (definition of unsteerable full castering nose wheel).
Third -- We all built our wheels to run straight and retract straight (as
best we could).
Fourth -- It is a fact that the centering mechanism, when seated, allows
about a degree or so slop in the wheel alignment. The slotted holes allow
several degrees of wheel movement.
So, the directions should be that the flange is adjusted so that the wheel,
when centered on extension, will retract into the well without hitting the
door or the sides.
Flight will be tomorrow -- I will let you all know if it didn't work.
BTW - Moral --- trust no-one, including yourself. Check everything twice.
Everyone is out to get you. Get other people to check your work, but don't
trust them either. Join my new group PEOPLE (Paranoia Explains Other
People's Lost Empathy). Trust me.
Scott Krueger (I promise I'll go straight)
N92EX
PS Jim Frantz - Possible 1 Sentence SDR -- LNC2 factory nose strut update may
require phalange exploratory examination for loose flange.
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LML homepage: http://www.olsusa.com/Users/Mkaye/maillist.html
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