Narrative:

During cockpit setup I ran the electric rudder trim in both directions. The trim pointer remained at zero, then jumped 5 units. Ran trim several times observing rudder pedals moving. About half of the times the pointer would hang up then jump. Maintenance replaced indicator before departure. At no time did the flag appear. I recommend during cockpit set up to actually operate the rudder trim rather than just checking for zero trim.

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Original NASA ASRS Text

Title: REPORTER DISCOVERS THAT RUDDER TRIM INDICATOR IS DEFECTIVE DURING HIS PREFLT INSPECTION.

Narrative: DURING COCKPIT SETUP I RAN THE ELECTRIC RUDDER TRIM IN BOTH DIRECTIONS. THE TRIM POINTER REMAINED AT ZERO, THEN JUMPED 5 UNITS. RAN TRIM SEVERAL TIMES OBSERVING RUDDER PEDALS MOVING. ABOUT HALF OF THE TIMES THE POINTER WOULD HANG UP THEN JUMP. MAINT REPLACED INDICATOR BEFORE DEP. AT NO TIME DID THE FLAG APPEAR. I RECOMMEND DURING COCKPIT SET UP TO ACTUALLY OPERATE THE RUDDER TRIM RATHER THAN JUST CHECKING FOR ZERO TRIM.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.