Narrative:

'Autoplt pitch trim' caution message was displayed on EICAS. First officer had control of aircraft, autoplt engaged. Captain directed first officer to maintain aircraft control while the QRH was referenced for corrective procedure. First officer noticed no abnormalities in aircraft attitude, autoplt remained engaged. QRH procedure was performed, and problem persisted, so in accordance with the QRH, the autoplt was disconnected and the aircraft was hand-flown by the first officer. Noticeable pitch-up forces were felt on the controls, which required a small amount of force to counteract at approximately 310 KIAS. Attempts to trim away this force were unsuccessful, as the pitch trim would not operate any farther in the nose-down direction (stick at an indication of '3'). Dispatch and maintenance were contacted before attempting any airspeed changes. When airspeed was decreased to about 290 KIAS, the nose down force required for level flight was reduced to zero at the current stabilizer trim setting. As airspeed was further reduced while descending into destination (250-270 KIAS) the aircraft required nose-up trim, which was easily attainable. The stabilizer trim then worked well in the nose-up and nose-down direction, at settings higher than at the time of the original caution message. All subsequent airspeed changes and confign changes were made in 10-20 KIAS increments, and all controllability contingencies (to include a go around) were fully briefed between the captain and first officer. A long, uneventful straight-in final approach was flown to destination, where a safe full stop landing was made. On the ground, it was noted that the stabilizer trim could not be adjusted to any setting lower than '3' in the nose down direction. Callback conversation with reporter revealed the following information: the reporter refused to answer any and all questions pertaining to the pitch trim and main electric trim failure until the ASRS identify strip is returned.

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Original NASA ASRS Text

Title: A CANADAIR CL65 IN CRUISE AT FL280 EXPERIENCED AUTOPLT PITCH TRIM AND MAIN ELECTRIC STABILIZER TRIM IN NOSE DOWN DIRECTION.

Narrative: 'AUTOPLT PITCH TRIM' CAUTION MESSAGE WAS DISPLAYED ON EICAS. FO HAD CTL OF ACFT, AUTOPLT ENGAGED. CAPT DIRECTED FO TO MAINTAIN ACFT CTL WHILE THE QRH WAS REFED FOR CORRECTIVE PROC. FO NOTICED NO ABNORMALITIES IN ACFT ATTITUDE, AUTOPLT REMAINED ENGAGED. QRH PROC WAS PERFORMED, AND PROB PERSISTED, SO IN ACCORDANCE WITH THE QRH, THE AUTOPLT WAS DISCONNECTED AND THE ACFT WAS HAND-FLOWN BY THE FO. NOTICEABLE PITCH-UP FORCES WERE FELT ON THE CTLS, WHICH REQUIRED A SMALL AMOUNT OF FORCE TO COUNTERACT AT APPROX 310 KIAS. ATTEMPTS TO TRIM AWAY THIS FORCE WERE UNSUCCESSFUL, AS THE PITCH TRIM WOULD NOT OPERATE ANY FARTHER IN THE NOSE-DOWN DIRECTION (STICK AT AN INDICATION OF '3'). DISPATCH AND MAINT WERE CONTACTED BEFORE ATTEMPTING ANY AIRSPD CHANGES. WHEN AIRSPD WAS DECREASED TO ABOUT 290 KIAS, THE NOSE DOWN FORCE REQUIRED FOR LEVEL FLT WAS REDUCED TO ZERO AT THE CURRENT STABILIZER TRIM SETTING. AS AIRSPD WAS FURTHER REDUCED WHILE DSNDING INTO DEST (250-270 KIAS) THE ACFT REQUIRED NOSE-UP TRIM, WHICH WAS EASILY ATTAINABLE. THE STABILIZER TRIM THEN WORKED WELL IN THE NOSE-UP AND NOSE-DOWN DIRECTION, AT SETTINGS HIGHER THAN AT THE TIME OF THE ORIGINAL CAUTION MESSAGE. ALL SUBSEQUENT AIRSPD CHANGES AND CONFIGN CHANGES WERE MADE IN 10-20 KIAS INCREMENTS, AND ALL CONTROLLABILITY CONTINGENCIES (TO INCLUDE A GAR) WERE FULLY BRIEFED BTWN THE CAPT AND FO. A LONG, UNEVENTFUL STRAIGHT-IN FINAL APCH WAS FLOWN TO DEST, WHERE A SAFE FULL STOP LNDG WAS MADE. ON THE GND, IT WAS NOTED THAT THE STABILIZER TRIM COULD NOT BE ADJUSTED TO ANY SETTING LOWER THAN '3' IN THE NOSE DOWN DIRECTION. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR REFUSED TO ANSWER ANY AND ALL QUESTIONS PERTAINING TO THE PITCH TRIM AND MAIN ELECTRIC TRIM FAILURE UNTIL THE ASRS IDENT STRIP IS RETURNED.

Data retrieved from NASA's ASRS site as of July 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.