Narrative:

Aircraft pushed back from gate xx at phl as air carrier X flight phl to bos. Ship pushback event was normal with appropriate checklists completed. Engines were started during pushback as would normally occur. At completion of pushback, brakes were set and push crew were cleared to disconnect by the captain. Push crew disconnected tow bar and interphone and said see you out front. Captain acknowledged. Engine start sequence was completed, after start checklist completed. Thumbs up given by push crew wave-off and thumbs up given by captain. As the aircraft taxied forward, the left engine struck the tug used to push the aircraft. Substantial damage to left engine occurred. No injuries to either push crew or passenger and crew reported at that time. For whatever reason, ground crew gave thumbs up when the aircraft was not clear of ground equipment. Tug was in a position not visible to the captain. Although standard push procedures are in effect at all air carrier X stations to prevent this type of accident, it occurred anyway. Procedures may need to be refined, perhaps by adding push crew members. Phl is very busy. Using 2 people for pushbacks may not be enough. It is not uncommon for both push crew members to be out of sight during the pushback sequence. Wave-off often not seen by both crew members in aircraft due to location of ground man during procedure.

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Original NASA ASRS Text

Title: FLC OF A B737-400 HIT THE TOW TUG DURING TAXI AFTER PUSHBACK CAUSING DAMAGE TO THE L ENG. NO ONE WAS INJURED.

Narrative: ACFT PUSHED BACK FROM GATE XX AT PHL AS ACR X FLT PHL TO BOS. SHIP PUSHBACK EVENT WAS NORMAL WITH APPROPRIATE CHKLISTS COMPLETED. ENGS WERE STARTED DURING PUSHBACK AS WOULD NORMALLY OCCUR. AT COMPLETION OF PUSHBACK, BRAKES WERE SET AND PUSH CREW WERE CLRED TO DISCONNECT BY THE CAPT. PUSH CREW DISCONNECTED TOW BAR AND INTERPHONE AND SAID SEE YOU OUT FRONT. CAPT ACKNOWLEDGED. ENG START SEQUENCE WAS COMPLETED, AFTER START CHKLIST COMPLETED. THUMBS UP GIVEN BY PUSH CREW WAVE-OFF AND THUMBS UP GIVEN BY CAPT. AS THE ACFT TAXIED FORWARD, THE L ENG STRUCK THE TUG USED TO PUSH THE ACFT. SUBSTANTIAL DAMAGE TO L ENG OCCURRED. NO INJURIES TO EITHER PUSH CREW OR PAX AND CREW RPTED AT THAT TIME. FOR WHATEVER REASON, GND CREW GAVE THUMBS UP WHEN THE ACFT WAS NOT CLR OF GND EQUIP. TUG WAS IN A POS NOT VISIBLE TO THE CAPT. ALTHOUGH STANDARD PUSH PROCS ARE IN EFFECT AT ALL ACR X STATIONS TO PREVENT THIS TYPE OF ACCIDENT, IT OCCURRED ANYWAY. PROCS MAY NEED TO BE REFINED, PERHAPS BY ADDING PUSH CREW MEMBERS. PHL IS VERY BUSY. USING 2 PEOPLE FOR PUSHBACKS MAY NOT BE ENOUGH. IT IS NOT UNCOMMON FOR BOTH PUSH CREW MEMBERS TO BE OUT OF SIGHT DURING THE PUSHBACK SEQUENCE. WAVE-OFF OFTEN NOT SEEN BY BOTH CREW MEMBERS IN ACFT DUE TO LOCATION OF GND MAN DURING PROC.

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.