Narrative:

At the beginning of our scheduled shift (2 round trips to phl from leb) the computer system indicated we were to be in the same aircraft until we reached phl the second time. However, our release out of leb the second time indicated that we were to swap into another aircraft. Neither the captain nor I caught this on the release. We were delayed out of leb by ATC. Both of us were concerned about making the edct and just overlooked the aircraft tail number switch and flew an aircraft that was not listed on the dispatch release. Supplemental information from acn 472801: I first became aware of my mistake when the first officer called in range and operations read back a different tail number. My errors were not checking the release during preflight as thoroughly as I should and not allowing that the initial ship's routing can and does change during the day.

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Original NASA ASRS Text

Title: ACR CREW FLIES THE INCORRECT ACFT.

Narrative: AT THE BEGINNING OF OUR SCHEDULED SHIFT (2 ROUND TRIPS TO PHL FROM LEB) THE COMPUTER SYS INDICATED WE WERE TO BE IN THE SAME ACFT UNTIL WE REACHED PHL THE SECOND TIME. HOWEVER, OUR RELEASE OUT OF LEB THE SECOND TIME INDICATED THAT WE WERE TO SWAP INTO ANOTHER ACFT. NEITHER THE CAPT NOR I CAUGHT THIS ON THE RELEASE. WE WERE DELAYED OUT OF LEB BY ATC. BOTH OF US WERE CONCERNED ABOUT MAKING THE EDCT AND JUST OVERLOOKED THE ACFT TAIL NUMBER SWITCH AND FLEW AN ACFT THAT WAS NOT LISTED ON THE DISPATCH RELEASE. SUPPLEMENTAL INFO FROM ACN 472801: I FIRST BECAME AWARE OF MY MISTAKE WHEN THE FO CALLED IN RANGE AND OPS READ BACK A DIFFERENT TAIL NUMBER. MY ERRORS WERE NOT CHKING THE RELEASE DURING PREFLT AS THOROUGHLY AS I SHOULD AND NOT ALLOWING THAT THE INITIAL SHIP'S ROUTING CAN AND DOES CHANGE DURING THE DAY.

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.