screen of the AVA) is to be subtracted from the initial
e. The target measurement for one station is equal to the initial station measurement (taken above), plus/minus
the table correction. Perform the same calculation for all six stations.
Maximum trim tab bending adjustment per flight for
one station is 0.030 inch in each direction from the
current setting. Do not over-bend trim tab.
Trim tabs should be bent uniformly at all six
Place center of the trim tab-bending tool over the measuring station. See figures 10 & 11.
Using a very light effort (to acquire a feel for the force needed to bend trim tab), bend tab. Check the
magnitude of adjustment using the trim tab measuring plate and adjust future bending effort based on this
experience. Repeat adjustment until the TARGET tab setting is obtained for that station. Perform this
procedure for all six-tab stations.
Annotate the new trim tab measurements on the trim tab position measurement record. A sample form is
shown on figure 12, but each blade should have a measurement record in the historical forms (green book).
Remove tab adjustment tools and perform limited test flight. Fly the aircraft and re-check the 1/REV vibrations
at the required flight conditions.