Falcon 900: Flap Drive Gearbox Gimbal Mounts

June 2010

Next time your flaps are off or during the removal and replacement of the flap drive 90° gear boxes, per maintenance procedure 27-521, pay particular attention to the orientation of the mounts attaching the gearboxes to the aft spar. These mounts, items 19 and 20 in fig 1 of the MP, not only have a "hat" which needs to be installed towards the gearbox gimbal, but the mount itself also must be orientated so that it does not contact the structure of the aircraft as the gearbox is flexing up and down during flap travel. Note that this mount is not symmetrical and if installed with the larger dimension to the spar, flap drive movement will be restricted with damage to the spar and mount.

For questions about this or other Falcon technical issues, contact your Duncan Aviation Falcon Tech Rep.