Hi all, Remi,
I'm not sure about that.
I had to replace my outer TP pins at 15 hours.
300++ hours later they are still OK, despite operating mostly from grass
strips.
In my opinion, the pins are very accurately made. But the holes in the
TP tubes are not. My new pins were set-up so that they had to be driven
in; I suspect this makes the difference. The PFA requirement is now for
an "interference" fit.
Duncan McF.
----- Original Message -----
From: R=C3=A9mi Guerner
To: europa-list@matronics.com
Sent: Sunday, June 24, 2007 9:56 AM
Subject: Europa-List: Tailplane flutter
The half inch play tolerance as specified by the factory means that,
in a more than one degree range, the tailplanes are not balanced at all.
This is a possible cause for flutter. I consider that any play in the
chain between the mass balance arm and the tailplanes is unacceptable:
that means zero play between TP4 and TP9 and zero play between TP 4 and
TP12. The factory solution is Mod 62: replacement of the =C2=BC=9D
pins by 3/8=9D pins. This mod is known to only delay, not
eliminate, the problem. As far as I know, there are 3 solutions which
have been implemented successfully by builders:
- gluing TP9 and TP12 to TP4
- replace the straight pins TP14C and TP14D by AN486 taper
pins
- replace the straight pins TP14C and TP14D by AN bolts
As some builders have mentioned in this forum in the past, all these
solutions have their own inconveniences and must be implemented
carefully, but I believe these inconveniences are far outweighed by the
safety of a fully balanced tailplane in all conditions.
Regards
Remi Guerner
F-PGKL, XS S/N395 monowheel, 912S, Airmaster, 482 hours
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