Narrative:

It seemed to be a normal takeoff; [but] on departure and climb out we noticed that the left engine vibration indicator was at 5.0. No vibration was felt from the controls or the aircraft. The lead flight attendant did mention that he felt a slight vibration on takeoff; but it went away once airborne. I directed the relief pilot to see if there was a checklist in our QRH dealing with this problem. The only one was dealing with a actual engine vibration and not with the indicator only. I asked him to call dispatch and maintenance on the satphone to get their inputs on our problem. The relief pilot went to the expanded engine performance page and read them the information. They advised for us to monitor and evaluate; but [left] it up to us to continue. The engine indications were within limits. N1 was the same as the right engine; the N2 was within 2%; fuel flow was about 600lbs/hr higher. Oil quantity; temperature; and pressure were all almost identical. Upon further evaluation; I wanted to receive more input to this problem. I called dispatch to let me talk to maintenance and someone from training. They coordinated a conference call between operations; maintenance; flight operations manager and dispatch. They wanted me to divert to XXX; because they had another aircraft for us to continue on to YYY and it would give us time to burn fuel to get to landing weight. I concurred and coordinated the divert. Once heading to XXX; we coordinated a fuel dump of 30;000 pounds. VMC weather allowed us to descend to 10;000 feet and burn off fuel to landing weight. A normal descent and landing were accomplished. It was not until parked at the gate when maintenance inform us that we had engine damage that we became aware of the extent of the damage.

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Original NASA ASRS Text

Title: The pilots of a B767 noticed a high engine vibration during takeoff and climb. All of the other engine parameters seemed normal; however after reviewing the situation with company personnel; it was determined that a precautionary diversion was prudent. After a successful landing; engine damaged was identified by Maintenance.

Narrative: It seemed to be a normal takeoff; [but] on departure and climb out we noticed that the left engine vibration indicator was at 5.0. No vibration was felt from the controls or the aircraft. The lead Flight Attendant did mention that he felt a slight vibration on takeoff; but it went away once airborne. I directed the Relief Pilot to see if there was a checklist in our QRH dealing with this problem. The only one was dealing with a actual engine vibration and not with the indicator only. I asked him to call Dispatch and Maintenance on the SATPHONE to get their inputs on our problem. The Relief Pilot went to the expanded engine performance page and read them the information. They advised for us to monitor and evaluate; but [left] it up to us to continue. The engine indications were within limits. N1 was the same as the right engine; the N2 was within 2%; fuel flow was about 600lbs/hr higher. Oil quantity; temperature; and pressure were all almost identical. Upon further evaluation; I wanted to receive more input to this problem. I called Dispatch to let me talk to Maintenance and someone from Training. They coordinated a conference call between Operations; Maintenance; Flight Operations Manager and Dispatch. They wanted me to divert to XXX; because they had another aircraft for us to continue on to YYY and it would give us time to burn fuel to get to landing weight. I concurred and coordinated the divert. Once heading to XXX; we coordinated a fuel dump of 30;000 pounds. VMC weather allowed us to descend to 10;000 feet and burn off fuel to landing weight. A normal descent and landing were accomplished. It was not until parked at the gate when Maintenance inform us that we had engine damage that we became aware of the extent of the damage.

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.