GRAUPNER heim Starlet 50 Mode D'emploi page 83

Starlet 50
Alternatively you could re-position the tail rotor gearbox flange 1292.7 slightly further aft on the
tail boom. Remove the tail boom from the mechanics again.
7.6 Connecting the tail boom to the mechanics
Withdraw the tail rotor assembly from the tail boom to the point where the shaft coupling
becomes accessible. Undo the grubscrews in the shaft coupling, so that the tail rotor shaft
4451.19 can be pulled out. Carefully de-grease the shaft, push it as far as it will go into the shaft
coupling, and secure it in this position with the grubscrews. This joint must be really firm. First
unscrew the grubscrews from the coupling entirely, apply thread-lock fluid, Order No. 952, or
bearing retainer fluid, Order No. 951, to the threaded holes, then re-fit the grubscrews and
tighten them fully. Even better, file or grind a flat in one side of the shaft where the grubscrews
engage, as this effectively prevents the shaft slipping in the joint. Fix the tail rotor to the tail rotor
gearbox flange 1292.7 securely using three 2.9 x 13 mm self-tapping screws. Lightly grease the
quick-release sleeve and the front end of the tail rotor shaft.
Attach the two tail boom braces to the left and right mechanics side frames using the stand-off
pillars 4445.12, which you prepared in Section 7.1.
The completed tail boom assembly can now be pushed into the tail boom flange 1292.5 as far
as it will go; check carefully that the quick-release coupling engages correctly. Rotate the tail
boom so that the curve of the boom runs upwards, and is exactly in the vertical plane, and
rotate the tail rotor flange so that the tail rotor shaft, when viewed from the tail, stands at right-
angles to the main rotor shaft. With the tail boom correctly aligned, tighten the M3 x 12 socket-
head cap screw in the tail boom flange to fix it in position. We recommend that you hold the tail
boom pointing vertically upwards while you tighten the clamping screw.
Adjust the position of the rear flange 1292.6 so that the tail boom braces 4445.8 can be
attached to it as shown in the drawing, using an M3 x 30 socket-head cap screw and an M3
self-locking nut.
Place the mechanical assembly on a perfectly flat table top, and adjust the position of the tail
boom brace flange until the bottom edge of the tail rotor flange 1292.7 is about 170 mm above
the surface of the table. In this position tighten the flange clamp securely, then drill 1.5 mm Ø
pilot-holes in the tail boom through the tail rotor flange 1292.7, the tail boom brace flange
1292.6 and the tail boom flange 1292.5. Fit the 2.2 x 6.5 mm self-tapping screws to prevent the
tail boom rotating or shifting position.
7.7 Stabiliser panels
(bag SR-3)
Fix the vertical stabiliser 1292.4 to the tail rotor flange using 2.9 x 13 mm self-tapping screws.
Attach the horizontal stabiliser to the tail boom by means of the stabiliser mount and the rod
guide, using 2.9 x 19 mm self-tapping screws. Set the horizontal stabiliser exactly at right-
angles to the vertical stabiliser; the distance between the horizontal stabiliser mount and the tail
rotor flange should be 200 mm. Tighten the retaining screws.
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