Narrative:

Control check on the ground was normal. Sometime after takeoff and during cruise climb the captain noticed a rolling moment and an unusual amount of rudder needed. Brought up the status page on EICAS and noticed the right inboard aileron position above the neutral index. During turns; noticed that the right inboard aileron would move up for right turns; but would not move down for left turns. The other ailerons were behaving normally. Being the relief pilot for this flight; I was elected to go back and visually check the control surfaces. Visual check confirmed the right inboard aileron was 'stuck' about 6 inches above the faired position in level flight. During turns; the aileron would move up; but not down below the 6 inches elevated position. Conferred with maintenance and dispatch and decided to declare an emergency and return to the departure airport. We took our time returning to burn excess fuel in order to land under maximum landing weight. We didn't find any checklist that dealt specifically with our problem; so we consulted several checklists; took information from those that was pertinent; and used our collective experience and judgment to preclude any further problems. We descended early to help burn fuel and configured early to determine any negative effects the stuck aileron might have on controllability. Captain decided to land with flaps at 20 due to the gusty winds reported and to have higher airflow over the other ailerons for controllability. The approach and landing was uneventful. Landing weight was approximately 315;000 lbs. Sometime after touchdown the right inboard aileron moved back to its normal 'drooped' position for the flap 20 setting. Conferred with maintenance and was told to leave flaps in the landing configuration for taxi-in. All things considered; I believe this incident was handled appropriately and professionally. The only unanticipated issue was getting the ground proximity. Warning for landing with flaps 20.

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Original NASA ASRS Text

Title: A B767 right inboard aileron remained deployed about six inches up in level flight which required unusual trim so an emergency was declared and the flight returned to the departure airport.

Narrative: Control check on the ground was normal. Sometime after takeoff and during cruise climb the Captain noticed a rolling moment and an unusual amount of rudder needed. Brought up the status page on EICAS and noticed the right inboard aileron position above the neutral index. During turns; noticed that the right inboard aileron would move up for right turns; but would not move down for left turns. The other ailerons were behaving normally. Being the Relief Pilot for this flight; I was elected to go back and visually check the control surfaces. Visual check confirmed the right inboard aileron was 'stuck' about 6 inches above the faired position in level flight. During turns; the aileron would move up; but not down below the 6 inches elevated position. Conferred with Maintenance and Dispatch and decided to declare an emergency and return to the departure airport. We took our time returning to burn excess fuel in order to land under maximum landing weight. We didn't find any checklist that dealt specifically with our problem; so we consulted several checklists; took information from those that was pertinent; and used our collective experience and judgment to preclude any further problems. We descended early to help burn fuel and configured early to determine any negative effects the stuck aileron might have on controllability. Captain decided to land with flaps at 20 due to the gusty winds reported and to have higher airflow over the other ailerons for controllability. The approach and landing was uneventful. Landing weight was approximately 315;000 lbs. Sometime after touchdown the right inboard aileron moved back to its normal 'drooped' position for the flap 20 setting. Conferred with Maintenance and was told to leave flaps in the landing configuration for taxi-in. All things considered; I believe this incident was handled appropriately and professionally. The only unanticipated issue was getting the GROUND PROX. warning for landing with Flaps 20.

Data retrieved from NASA's ASRS site as of July 2013 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.