Narrative:

Soon after takeoff from ZZZ, captain flying with autoplt, it became apparent that, if the sidestick was released, the aircraft would gradually nose over into an increasing angle of descent. Once in cruise and stabilized, the flight crew determined that about 1.5 cm of backstick pressure was required to keep the ship level, or in whatever angle of climb or descent was required. If the sidestick was released, the autotrim would commence trimming nose down slowly. With either autoplt on, the aircraft would maintain the correct attitude. Various tests were performed which indicated that both sidesticks were affected, and autothrust or flight/director on or off had no effect. Maintenance control and dispatch were contacted via radio and the situation discussed. Conjecture was that elac #2 might be the problem but it was agreed not to cycle flight control computers. Also, since there were no ECAM indications or flight control difficulties of a mechanical nature, and the autoplts kept things stable, it was agreed that a divert was not warranted. The crew reviewed the applicable system in volume 1 of the fcom and conducted a plan of action in the event the situation deteriorated. The flight could have been conducted at FL390, but the crew elected to cruise at FL350 to provide greater maneuvering margins if necessary. On arrival in ZZZ1, a flaps 3 degrees normal landing was selected to ensure sufficient nose up authority/authorized in the flare. The autoplt and autothrust were disconnected at 8000 ft to get a good feel for controling the ship and the arrival and landing were manually flown to an uneventful landing. No emergency was declared as full control was maintained at all times. Great input and teamwork from the first officer contributed to a successful conclusion. Callback conversation with reporter revealed the following information: the reporter stated the maintenance findings and fix was replacement of the #1 and #2 elevator and aileron computers (elac) and rerigging the elevator and stabilizer controls. The reporter said it was disappointing that it took so long to discover this fault but this airplane is so seldom hand flown.

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Original NASA ASRS Text

Title: AN A320 CREW REPORTS A GRADUAL PITCH DOWN MOVEMENT UNLESS CONSTANT SIDESTICK UP PRESSURE IS MAINTAINED. #1 AND #2 ELEVATOR AND AILERON (ELAC) COMPUTERS WERE REPLACED.

Narrative: SOON AFTER TKOF FROM ZZZ, CAPT FLYING WITH AUTOPLT, IT BECAME APPARENT THAT, IF THE SIDESTICK WAS RELEASED, THE ACFT WOULD GRADUALLY NOSE OVER INTO AN INCREASING ANGLE OF DSCNT. ONCE IN CRUISE AND STABILIZED, THE FLT CREW DETERMINED THAT ABOUT 1.5 CM OF BACKSTICK PRESSURE WAS REQUIRED TO KEEP THE SHIP LEVEL, OR IN WHATEVER ANGLE OF CLB OR DSCNT WAS REQUIRED. IF THE SIDESTICK WAS RELEASED, THE AUTOTRIM WOULD COMMENCE TRIMMING NOSE DOWN SLOWLY. WITH EITHER AUTOPLT ON, THE ACFT WOULD MAINTAIN THE CORRECT ATTITUDE. VARIOUS TESTS WERE PERFORMED WHICH INDICATED THAT BOTH SIDESTICKS WERE AFFECTED, AND AUTOTHRUST OR FLT/DIRECTOR ON OR OFF HAD NO EFFECT. MAINT CTL AND DISPATCH WERE CONTACTED VIA RADIO AND THE SIT DISCUSSED. CONJECTURE WAS THAT ELAC #2 MIGHT BE THE PROB BUT IT WAS AGREED NOT TO CYCLE FLT CTL COMPUTERS. ALSO, SINCE THERE WERE NO ECAM INDICATIONS OR FLT CTL DIFFICULTIES OF A MECHANICAL NATURE, AND THE AUTOPLTS KEPT THINGS STABLE, IT WAS AGREED THAT A DIVERT WAS NOT WARRANTED. THE CREW REVIEWED THE APPLICABLE SYS IN VOLUME 1 OF THE FCOM AND CONDUCTED A PLAN OF ACTION IN THE EVENT THE SIT DETERIORATED. THE FLT COULD HAVE BEEN CONDUCTED AT FL390, BUT THE CREW ELECTED TO CRUISE AT FL350 TO PROVIDE GREATER MANEUVERING MARGINS IF NECESSARY. ON ARR IN ZZZ1, A FLAPS 3 DEGS NORMAL LNDG WAS SELECTED TO ENSURE SUFFICIENT NOSE UP AUTH IN THE FLARE. THE AUTOPLT AND AUTOTHRUST WERE DISCONNECTED AT 8000 FT TO GET A GOOD FEEL FOR CTLING THE SHIP AND THE ARR AND LNDG WERE MANUALLY FLOWN TO AN UNEVENTFUL LNDG. NO EMER WAS DECLARED AS FULL CTL WAS MAINTAINED AT ALL TIMES. GREAT INPUT AND TEAMWORK FROM THE FO CONTRIBUTED TO A SUCCESSFUL CONCLUSION. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE MAINT FINDINGS AND FIX WAS REPLACEMENT OF THE #1 AND #2 ELEVATOR AND AILERON COMPUTERS (ELAC) AND RERIGGING THE ELEVATOR AND STABILIZER CTLS. THE RPTR SAID IT WAS DISAPPOINTING THAT IT TOOK SO LONG TO DISCOVER THIS FAULT BUT THIS AIRPLANE IS SO SELDOM HAND FLOWN.

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.