I think everyone`s had to put up with the twist about the longitudinal fus.
axis and which results in the tailplanes being + and - 3mm misaligned with
the fairings on the fus. side.
I also had the problem of the centreline of the rear of the fus. being
skewed in relation to the rest. My concern was that this would also offset
the fin the "wrong" way when things got that far. This wouldn`t have
mattered much with a 912, but the engine I have installed rotates in the
opposite direction. However, it was possible to remove the skew by holding
the lower fus. half in an external former bonded temporarily to the outside
at the location of the fin post. Additionally and whilst the skew was held
out, a temporary shear web was bonded across the inside of the tailcone.
These braces were only removed after the whole fus. had been structurally
completed. Its all abit of a compromise, but zero incidence was achieved on
the fin.
The force required to hold the correct alignment was actually very small, so
I`m not too concerned about building-in stresses that weren`t part of the
original design.
If thats all abit unclear then let me know and I`ll expand off-forum.
Duncan McFadyean
-----Original Message-----
From: William McClellan <wilmac@gte.net>
Date: Sunday, March 19, 2000 7:31 PM
Subject: Tail Twist
>To all,
>
>I have a twist clockwise or to port in my rear fuselage (under
>construction). Also the starboard side of the lower fuselage half tail
>surface is curved in more than the port side making the centerline
>between the two crossed for centering the torque-tube and also the line
>between the two front flange (for gluing to the upper fuselage half)
>corners are not horizontal or level. This is before and after I fix the
>distance between the points as the manual stipulates. As I am
>installing the tail bulkhead I am concerned that if I epoxy it in place
>without correcting this twqist, I will make the twist more permanent.
>My plan is to epoxy with the tapes only the starboard lower quadrant of
>the bulkhead in place, then manually twist the fuselage to correct
>position and then epoxy the rest of the bulkhead in place, thus not
>making the deformity/twist permanent.
>
>Has anyone had this problem? Has anyone successfully corrected this
>twist?
>
>Thanks,
>Bill McClellan A164
>
>
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