Karl
I think that when the cause is eventually discovered - it will be found to
be a combination of two or more conditions that individually, would not
cause a problem.
One Pip-Pin was found to be bent through 90 degrees, implying that one
tailplane did rotate and that TP4 remained in place. I would guess that the
TP6 remained firmly anchored to the torque tube by the pin and the rest of
the structure broke loose and rotated around it.
A few years back I witnessed a formula one fatal at Reno, right in front of
our grandstand. The aircraft suffered a tailplane flutter which resulted in
four or five violent pitch up/down cycles before the tail broke free and the
aircraft pitched into the ground. The whole incident probably took no more
than 2.5 seconds from start to sad end. The torsional load on the main wing
spars must have been phenomenal and it would be easy to understand how a
main plane could fail following a tailplane flutter.
With regard to suitable repairs. I have thought long and hard about this
(and so are the guys at the PFA) and the truth is that there is no quick
fix. Regardless of whatever method is devised to locate the tail laterally,
the fact remains that a disbonded TP5 and TP6 will prevent the tailplane
locating accurately on TP4 - and this must be addressed.
The Mod 73 Pip-pin reinforcement is a good short term fix (the sticking
plaster).
To retro-fit the tailplane mod would require that the entire tailplane be
dismantled and rebuilt .....possible, but by no means easy.
In my opinion it would be easier to build new tailplanes (and if I was in
this predicament, this would be my chosen course of action).
I quite enjoyed building mine and it didn't take that long.
How about someone (Europa 2004?) producing new tail kits (Tailplanes only)
and offer these to existing Europa owners at cost plus. I reckon they could
be produced for around 400-500 GPB ($800-$1000 USD) plus shipping. It's an
idea to keep the discussion rolling......
Nigel
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com]On Behalf Of Karl Heindl
Sent: 15 July 2007 14:50
Subject: RE: Europa-List: Europa Tailplane - Mod 73
Nigel,
I understand all that and your mod should have been made standard a long
time ago. But what about older Europas ? We hear reports about disbonded
TP6s but we don't hear how they were repaired. I really would like to know.
A suitable retrofit mod should also have been made available as soon as this
problem was known.
I still say that there is no way the tailplane can move if the pip pin head
is firmly against solid material on the inboard side. You say there is
always a gap, but that gap is filled with floxed epoxy, and the head is
inside a close fitting plastic pipe in my case. I think another builder
recently told us about a similar mod he made. The remaining space around the
pipe is also filled with epoxy. Of course all these solutions are based on
theory and only a lab test could verify the claims.
When my TP5s disbonded from trailering I was kicking myself for not having
installed a one-piece pipe, but in those early days I was very careful to
follow the build instructions precisely. I stll think that a retrofit of a
one-piece sleeve would be more than strong enough to prevent any future
disbonding, and would be a relatively easy solution where the TP6s have
already disbonded.
As far as the accident goes, we still don't have any real conclusive
evidence about the sequence of events. Only a number of theories. Only a
wind tunnel test would verify the flutter theory, but who is going to pay
for that ? Eyewitness reports can be very misleading.
If the wing trailing edge pin came off first, is it possible that the pilot
was getting set up for landing and deploying flaps and undercarriage ?
I also like the other suggested solutions where a lock is put behind the
TP12
Karl
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