Rob,
I can really feel with you, having just completed MOD 73. The manual
falls short to say that you ought NOT to insert the tail planes so deep
into the torque tube that the two retaining pins would contact or even
insert into the bushings fitted to the tailplane root.
I was lucky on the first one which refused to insert because the layup
is performed on the opposite side. It was EASY to crack the torque tube
to retaining layup by TWISTING the tailplane against the torque tube.
Came right off no problem. I was not worried either as the inner tube
was greased.
What compelled me with my second tailplane to push it that far in to
allow the pins to insert I don't know as I should have used my head, not
the description in the MOD manual. Next morning wanting to separate the
tailplane from the torque tube turned out to take several hours. Yes, I
admit I showed up with a hammer, pry bars etc, but after initially
starting to damage a bit of the root layup by prying I decided not to
proceed. Instead I disassembled the entire torque tube which had been
there for years and took all out. Took me 2 hours. From there it was
easy as the pin retaining welded part could be removed and the tailplane
cracked loose by a twist.
In hind sight I am glad I did not use the hammer. This can be extremely
damaging to internal parts in the tailplane like hair cracks. My
recommendation is to just insert the torque tube sufficiently into the
inner tube at time of layup so that pins stay out of the way. This
should be added to the current MOD 73 instructions.
Best,
Christoph Both
@223
Wolfville, Nova Scotia Canada
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Rob Housman
Sent: Monday, September 29, 2008 11:52 AM
Subject: Europa-List: Mod 72 - Undercarriage mounting frame
strengthening
Having been working mostly on those factory mandated or recommended
modifications of late, I now realize that it is much easier to build an
airplane than it is to repair one. Mod 70 (Mass balance arm) was merely
tedious, working deep in the tailcone, one handed, through small access
holes, but Mod 73 (Tailplane retention) and Mod 59 (Shimmy damper) did
not go well when following the written procedures, and now with Mod 72
there is more of that wonderful English understatement: "Insert the
tubes - they will probably need a light tap to fit them" it says in the
procedure. English hammers must be considerably larger and heavier than
American hammers (or 16.5 mm reamers must be a bit larger) because "a
light tap" does nothing. After pounding away for entirely too long, and
peening the ends of the tubes where the hammer repeatedly struck, I
finally fabricated a steel spud to put between the offending pin and the
hammer. This made it easier to keep pounding with less damage to the
pins, or to the adjacent smaller diameter tubes to which the engine
mounts attach if I were to miss the target. The steel spud is starting
to look like a mushroom from all of those "light taps."
I should have retained my initial skepticism regarding the fit of
painted tubes, which after painting with etch primer are larger than
16.5mm, but no, I foolishly believed that the factory had actually tried
this procedure. Well folks, the paint makes the pin almost impossible
to fit.
Fearing complaints from my neighbors about so much hammering on a
peaceful Sunday afternoon I finally quit pounding with the intention of
resuming mid-day today when most of my neighbors will be away at work.
As of yesterday afternoon one pin was snug against the bolt attaching
the frame to the fuselage and the other was still barely halfway home.
Now, if I could find one of those English hammers at Home Depot....
Best regards,
Rob Housman
Irvine, CA
Europa XS Tri-Gear
A070
Airframe complete
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