Falcon 20 first officer reported noticing abnormally high nose down tendency on approach; and after ...

Narrative:

On approach into shv runway 14; after autopilot disengaged; I flew from approximately 2000 ft AGL to short final using what felt like more aft pressure than normal; maintaining controllability and remaining on approach profile and proper airspeed. Upon landing at 20 ft AGL during the landing flare I stated to my captain that the yoke had hit the aft stop. A normal landing occurred. During the 'after landing' checklist it was observed that the trim was in the full nose down position; and could not be returned to the takeoff position using normal trim. Emergency trim worked normally allowing the crew to move the trim to the normal takeoff position. Upon reengaging the normal trim circuit breaker the trim drove itself to the full nose down position again.

Original NASA ASRS Text

Title: Falcon 20 First Officer reported noticing abnormally high nose down tendency on approach; and after landing stabilizer trim was found in full nose down position. Trimming nose up with the normal system had no effect; but emergency trim did work.

Narrative: On approach into SHV runway 14; after autopilot disengaged; I flew from approximately 2000 FT AGL to short final using what felt like more aft pressure than normal; maintaining controllability and remaining on approach profile and proper airspeed. Upon landing at 20 FT AGL during the landing flare I stated to my Captain that the yoke had hit the aft stop. A normal landing occurred. During the 'after landing' checklist it was observed that the trim was in the full nose down position; and could not be returned to the takeoff position using normal trim. Emergency trim worked normally allowing the crew to move the trim to the normal takeoff position. Upon reengaging the normal trim circuit breaker the trim drove itself to the full nose down position again.

Data retrieved from NASA's ASRS site 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.

Attributes
ACN	1224671
Time
Date	201412
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ
State Reference	US
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	Falcon 20FJF/20C/20D/20E/20F
Operating Under FAR Part	Part 91
Flight Phase	Landing
Component
Aircraft Component	Horizontal Stabilizer Trim
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe

Falcon 20 first officer reported noticing abnormally high nose down tendency on approach; and after landing stabilizer trim was found in full nose down position. Trimming nose up with the normal system had no effect; but emergency trim did work.