Narrative:

Approx 2.3 hours into flight was contacted by dispatch via satcom. We were informed that a 3'x5' piece of #1 engine cowling had fallen off the aircraft during takeoff roll. We were at FL380 in continuous light to moderate turbulence. All engine and other indications were normal. Fuel burn was approximately 2;300 lbs more than planned. On climb out; the aircraft required approx 1.1 units of right rudder trim in order to center 'the ball'. After the info from dispatch; the rudder trim requirement appeared to confirm additional drag from #1 engine. Approach was notified and emergency response crews were coordinated. Uneventful approach and landing. #1 thrust reverser was not utilized in order to prevent further damage. During taxi in; emergency response vehicle informed us that #1 engine looked ok; but #2 engine looked damaged. Post flight inspection confirmed damage to #2. Maintenance work had been performed on #2 engine two days prior. I do not know what caused this event. Aircrew preflight walk around inspection appeared normal. Perhaps additional maintenance inspection? It would have been very helpful if maintenance would have identified the correct engine! Further damage to #2 thrust reverser; engine cowls; etc could have been prevented.

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Original NASA ASRS Text

Title: DC-10 First Officer is informed 2.3 hours into flight that a large piece of the number one engine cowl departed the aircraft during takeoff. An emergency is declared for landing at destination where it is discovered that the number two engine is missing part of its cowl. Maintenance had been preformed on the engine two days prior.

Narrative: Approx 2.3 hours into flight was contacted by Dispatch via SATCOM. We were informed that a 3'x5' piece of #1 engine cowling had fallen off the aircraft during takeoff roll. We were at FL380 in continuous light to moderate turbulence. All engine and other indications were normal. Fuel burn was approximately 2;300 lbs more than planned. On climb out; the aircraft required approx 1.1 units of right rudder trim in order to center 'the ball'. After the info from Dispatch; the rudder trim requirement appeared to confirm additional drag from #1 engine. Approach was notified and emergency response crews were coordinated. Uneventful approach and landing. #1 thrust reverser was not utilized in order to prevent further damage. During taxi in; emergency response vehicle informed us that #1 engine looked ok; but #2 engine looked damaged. Post flight inspection confirmed damage to #2. Maintenance work had been performed on #2 engine two days prior. I do not know what caused this event. Aircrew preflight walk around inspection appeared normal. Perhaps additional maintenance inspection? It would have been very helpful if Maintenance would have identified the correct engine! Further damage to #2 thrust reverser; engine cowls; etc could have been prevented.

Data retrieved from NASA's ASRS site 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.