Narrative:

During climb out of ZZZ. The stabilizer trim would not trim more than 4.2 units nose down. Autoplt was unable to trim the aircraft either. Trouble shooting was conducted to determine the controllability of the aircraft. Trim was available aft but no more than previously stated 4.2 units nose down. Maintenance control was contacted but offer no new ideas. Flight continued to destination at lower altitude and reduced airspeed for controllability and comfort of pilots flying by hand. QRH was consulted with no procedures so stabilizer 1 and 2 inoperative was used as a gridline and a altitude landing flap setting was used. ATC was advised of the situation and our reduced airspeed, but no other assistance was requested or required. Flight and landing was otherwise normal and uneventful. Callback conversation with reporter revealed the following information: the reporter stated the replacement of the main electric actuator corrected the problem. The reporter said the autoplt actuator should have been replaced as it also was inoperative. The reporter stated it was his belief that one failed actuator could not lock up the other actuator as built in clutches would disengage the failed actuator. The reporter said reports of stabilizer trim failures are not out of the ordinary but occur mainly on the ground. The reporter stated this airplane was not parked in the rain or snow overnight and WX was not a cause.

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Original NASA ASRS Text

Title: A CANADAIR CL-65 IN CLB AT 12000 FT HAD AUTOPLT STAB TRIM WARNING. SWITCHED OFF AUTOPLT AND FOUND MAIN ELECTRIC TRIM ALSO INOPERATIVE. CAUSED BY FAILED MAIN ELECTRIC ACTUATOR.

Narrative: DURING CLB OUT OF ZZZ. THE STAB TRIM WOULD NOT TRIM MORE THAN 4.2 UNITS NOSE DOWN. AUTOPLT WAS UNABLE TO TRIM THE ACFT EITHER. TROUBLE SHOOTING WAS CONDUCTED TO DETERMINE THE CONTROLLABILITY OF THE ACFT. TRIM WAS AVAILABLE AFT BUT NO MORE THAN PREVIOUSLY STATED 4.2 UNITS NOSE DOWN. MAINT CTL WAS CONTACTED BUT OFFER NO NEW IDEAS. FLT CONTINUED TO DESTINATION AT LOWER ALTITUDE AND REDUCED AIRSPEED FOR CONTROLLABILITY AND COMFORT OF PLTS FLYING BY HAND. QRH WAS CONSULTED WITH NO PROCS SO STAB 1 AND 2 INOP WAS USED AS A GRIDLINE AND A ALT LANDING FLAP SETTING WAS USED. ATC WAS ADVISED OF THE SIT AND OUR REDUCED AIRSPEED, BUT NO OTHER ASSISTANCE WAS REQUESTED OR REQUIRED. FLT AND LNDG WAS OTHERWISE NORMAL AND UNEVENTFUL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE REPLACEMENT OF THE MAIN ELECTRIC ACTUATOR CORRECTED THE PROB. THE RPTR SAID THE AUTOPLT ACTUATOR SHOULD HAVE BEEN REPLACED AS IT ALSO WAS INOPERATIVE. THE RPTR STATED IT WAS HIS BELIEF THAT ONE FAILED ACTUATOR COULD NOT LOCK UP THE OTHER ACTUATOR AS BUILT IN CLUTCHES WOULD DISENGAGE THE FAILED ACTUATOR. THE RPTR SAID RPTS OF STABILIZER TRIM FAILURES ARE NOT OUT OF THE ORDINARY BUT OCCUR MAINLY ON THE GND. THE RPTR STATED THIS AIRPLANE WAS NOT PARKED IN THE RAIN OR SNOW OVERNIGHT AND WX WAS NOT A CAUSE.

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.