Narrative:

During climbout from ZZZ aircraft displayed yaw oscillations that were very small in magnitude. Oscillations stopped near or at level off. No change with autoplt on or off, yaw dampers on or off. Flight to ZZZ1 completed without further incident. Supplemental information from acn 536731: I was the captain of flight abcd, ZZZ to ZZZ1 aircraft X. During climb out of 10000 ft, co-pilot and I noticed a yawing motion of the aircraft, very small in magnitude, as if someone was pushing on the rudder pedals (left and right, and right and left) back and forth. We tried to identify the problem by looking at the ECAM page and noticed slight rudder movements without either of us pushing on the rudder pedals. We then proceeded to turn off the yaw dampers one at a time, then both. The aircraft continued to yaw back and forth. We also turned off the flight directors, but the yawing continued. We then turned the autoplts on, but the yawing continued. We decided to level off at FL240. As power was reduced, the aircraft stopped yawing as we leveled off. We then decided to continue to climb up to cruise altitude. When climb power was reinstated and climb initiated, the aircraft started to yaw back and forth again in small rhythmic oscillations 1 to 1.5 per second, until we leveled off at a cruising altitude of FL350. The yawing stopped at cruise altitude. There was no further yawing of the aircraft in cruise flight or during descent to landing. The landing was normal. Upon arrival into ZZZ1 I wrote an entry in the aircraft log book. Callback conversation with reporter revealed the following information: the reporter stated the oscillations were observed in the rudder pedals in climb only and was not noticeable in the aft cabin. The reporter said when leveling off the oscillations stopped. The reporter stated this oscillation has been observed by him before and believes it is caused by a combination of aircraft weight, center of gravity and climb. The reporter said after level off in cruise and until landing in ZZZ1 no oscillations occurred.

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Original NASA ASRS Text

Title: AN AIRBUS 300-600 ON CLBOUT DISPLAYED SMALL OSCILLATIONS IN RUDDER AND RUDDER PEDALS. YAW DAMPER ON OR OFF, AUTOPLT ON OR OFF. OSCILLATIONS STOPPED IN LEVEL OFF.

Narrative: DURING CLIMBOUT FROM ZZZ ACFT DISPLAYED YAW OSCILLATIONS THAT WERE VERY SMALL IN MAGNITUDE. OSCILLATIONS STOPPED NEAR OR AT LEVEL OFF. NO CHANGE WITH AUTOPLT ON OR OFF, YAW DAMPERS ON OR OFF. FLT TO ZZZ1 COMPLETED WITHOUT FURTHER INCIDENT. SUPPLEMENTAL INFO FROM ACN 536731: I WAS THE CAPT OF FLT ABCD, ZZZ TO ZZZ1 ACFT X. DURING CLB OUT OF 10000 FT, CO-PLT AND I NOTICED A YAWING MOTION OF THE ACFT, VERY SMALL IN MAGNITUDE, AS IF SOMEONE WAS PUSHING ON THE RUDDER PEDALS (L AND R, AND R AND L) BACK AND FORTH. WE TRIED TO IDENTIFY THE PROB BY LOOKING AT THE ECAM PAGE AND NOTICED SLIGHT RUDDER MOVEMENTS WITHOUT EITHER OF US PUSHING ON THE RUDDER PEDALS. WE THEN PROCEEDED TO TURN OFF THE YAW DAMPERS ONE AT A TIME, THEN BOTH. THE ACFT CONTINUED TO YAW BACK AND FORTH. WE ALSO TURNED OFF THE FLT DIRECTORS, BUT THE YAWING CONTINUED. WE THEN TURNED THE AUTOPLTS ON, BUT THE YAWING CONTINUED. WE DECIDED TO LEVEL OFF AT FL240. AS POWER WAS REDUCED, THE ACFT STOPPED YAWING AS WE LEVELED OFF. WE THEN DECIDED TO CONTINUE TO CLB UP TO CRUISE ALTITUDE. WHEN CLB POWER WAS REINSTATED AND CLB INITIATED, THE ACFT STARTED TO YAW BACK AND FORTH AGAIN IN SMALL RHYTHMIC OSCILLATIONS 1 TO 1.5 PER SEC, UNTIL WE LEVELED OFF AT A CRUISING ALTITUDE OF FL350. THE YAWING STOPPED AT CRUISE ALTITUDE. THERE WAS NO FURTHER YAWING OF THE ACFT IN CRUISE FLT OR DURING DSCNT TO LNDG. THE LNDG WAS NORMAL. UPON ARR INTO ZZZ1 I WROTE AN ENTRY IN THE ACFT LOG BOOK. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE OSCILLATIONS WERE OBSERVED IN THE RUDDER PEDALS IN CLB ONLY AND WAS NOT NOTICEABLE IN THE AFT CABIN. THE RPTR SAID WHEN LEVELING OFF THE OSCILLATIONS STOPPED. THE RPTR STATED THIS OSCILLATION HAS BEEN OBSERVED BY HIM BEFORE AND BELIEVES IT IS CAUSED BY A COMBINATION OF ACFT WT, CENTER OF GRAVITY AND CLB. THE RPTR SAID AFTER LEVEL OFF IN CRUISE AND UNTIL LNDG IN ZZZ1 NO OSCILLATIONS OCCURRED.

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.