Narrative:

On departure from runway 33 at lima using maximum power due to acceptable tailwind we began our takeoff roll. Prior to rotation I noticed what looked like a bird running across the runway in front of the aircraft. Seeing normal engine indications we continued the takeoff. Once in the air, I noticed a low pitched rumbling sound followed by the right engine vibrations indicator turning amber and displaying the number 5. We notified ATC that we had a problem and wanted to return to the field. The flight attendants then called to tell us they heard a loud rumbling and that they saw sparks coming from the cowl area of the right engine. I then declared an emergency and we received vectors back for an approach to runway 15. I notified the flight attendants that we did not anticipate an evacuate/evacuation and that they should not begin one without hearing from me. When the throttle of the right engine was retarded, the vibration indicator returned to normal so the engine was not shut down. Landing was made overweight, at 238000 pounds and touchdown was smooth. Upon returning to the gate and shutting down, we observed that 2 engine fan blades were bent, apparently from the impact with whatever we hit, believed to be a bird.

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Original NASA ASRS Text

Title: A B757 CREW, DEPARTING LIMA (SPIM), INGESTED A BIRD(S) INTO THE R ENG ON TKOF, REQUIRING A RETURN TO DEP ARPT WITH AN OVERWT LNDG BEING MADE.

Narrative: ON DEP FROM RWY 33 AT LIMA USING MAX PWR DUE TO ACCEPTABLE TAILWIND WE BEGAN OUR TKOF ROLL. PRIOR TO ROTATION I NOTICED WHAT LOOKED LIKE A BIRD RUNNING ACROSS THE RWY IN FRONT OF THE ACFT. SEEING NORMAL ENG INDICATIONS WE CONTINUED THE TKOF. ONCE IN THE AIR, I NOTICED A LOW PITCHED RUMBLING SOUND FOLLOWED BY THE R ENG VIBRATIONS INDICATOR TURNING AMBER AND DISPLAYING THE NUMBER 5. WE NOTIFIED ATC THAT WE HAD A PROB AND WANTED TO RETURN TO THE FIELD. THE FLT ATTENDANTS THEN CALLED TO TELL US THEY HEARD A LOUD RUMBLING AND THAT THEY SAW SPARKS COMING FROM THE COWL AREA OF THE R ENG. I THEN DECLARED AN EMER AND WE RECEIVED VECTORS BACK FOR AN APCH TO RWY 15. I NOTIFIED THE FLT ATTENDANTS THAT WE DID NOT ANTICIPATE AN EVAC AND THAT THEY SHOULD NOT BEGIN ONE WITHOUT HEARING FROM ME. WHEN THE THROTTLE OF THE R ENG WAS RETARDED, THE VIBRATION INDICATOR RETURNED TO NORMAL SO THE ENG WAS NOT SHUT DOWN. LNDG WAS MADE OVERWT, AT 238000 LBS AND TOUCHDOWN WAS SMOOTH. UPON RETURNING TO THE GATE AND SHUTTING DOWN, WE OBSERVED THAT 2 ENG FAN BLADES WERE BENT, APPARENTLY FROM THE IMPACT WITH WHATEVER WE HIT, BELIEVED TO BE A BIRD.

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.