Narrative:

As the plane began to lift off the runway I heard and felt a loud thump with air rushing as if into a large vacuum. My thought was the fuselage had ruptured and was coming apart. The rattle and vibration from the left engine was so strong I thought it was ripping away from the wing. When we were informed it had been a bird strike I did feel some relief; but the noise and vibration from the engine was still prevalent. A passenger began having chest pain and we paged for a physician. Someone responded to the request; but had no credentials and was not allowed to tend to the passenger. We were told by the captain that he had declared an emergency; but told us not to prepare as there was no time. We did our normal checks and returned to our jumpseats. We were unable to dump fuel to lighten the airplane and we landed heavy; you could feel that as we touched down. The landing was hard; but also smooth and controlled; meaning we did not bounce or sway. We taxied to the apron where paramedics came to get the passenger. We sat on the apron for a bit as the brakes were overheated. They towed us to a gate and passengers were deplaned normally via the jet bridge.

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Original NASA ASRS Text

Title: A B767-300ER returned to the departure airport with a seriously vibrating left engine after ingesting a bird on takeoff.

Narrative: As the plane began to lift off the runway I heard and felt a loud thump with air rushing as if into a large vacuum. My thought was the fuselage had ruptured and was coming apart. The rattle and vibration from the left engine was so strong I thought it was ripping away from the wing. When we were informed it had been a bird strike I did feel some relief; but the noise and vibration from the engine was still prevalent. A passenger began having chest pain and we paged for a physician. Someone responded to the request; but had no credentials and was not allowed to tend to the passenger. We were told by the Captain that he had declared an emergency; but told us not to prepare as there was no time. We did our normal checks and returned to our jumpseats. We were unable to dump fuel to lighten the airplane and we landed heavy; you could feel that as we touched down. The landing was hard; but also smooth and controlled; meaning we did not bounce or sway. We taxied to the apron where paramedics came to get the passenger. We sat on the apron for a bit as the brakes were overheated. They towed us to a gate and passengers were deplaned normally via the jet bridge.

Data retrieved from NASA's ASRS site as of April 2012 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.