Narrative:

First officer flying, captain operating radios. Level at FL330, ZDC instructs, 'air carrier X, descend and maintain FL290.' the captain reads back 'descend to FL290, air carrier X.' after confirming the altitude with the captain by pointing at the selected altitude, I started my descent. After passing FL326, ATC instructed us to climb back up to FL330, as the instruction was for air carrier Y. We had been following 'air carrier Y from south florida and were listening carefully as we had similar call signs. Both the captain and I can be assured that ATC called 'air carrier X and not air carrier Y.' after arriving in pit, I talked to ZDC supervisor who had not listened to the tapes yet but said that they (ZDC) have been having trouble with the 2 call signs for awhile. I said that I would talk to dispatch to see if they could make any modifications to the similar sounding call signs. After hanging up with ATC, I contacted dispatch, as he was at the desk that air carrier X was dispatched from. He noted that air carrier Y departed pbi mins before we departed fll and had the exact same route. He made a note to have the call signs adjusted to prevent further confusion.

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Original NASA ASRS Text

Title: B737-300 CREW AND SAME ACR WITH A SIMILAR CALL SIGN, HAD THE ZDC RADAR CTLR ISSUE A CLRNC TO THE WRONG ACFT IN ZDC CLASS A.

Narrative: FO FLYING, CAPT OPERATING RADIOS. LEVEL AT FL330, ZDC INSTRUCTS, 'ACR X, DSND AND MAINTAIN FL290.' THE CAPT READS BACK 'DSND TO FL290, ACR X.' AFTER CONFIRMING THE ALT WITH THE CAPT BY POINTING AT THE SELECTED ALT, I STARTED MY DSCNT. AFTER PASSING FL326, ATC INSTRUCTED US TO CLB BACK UP TO FL330, AS THE INSTRUCTION WAS FOR ACR Y. WE HAD BEEN FOLLOWING 'ACR Y FROM SOUTH FLORIDA AND WERE LISTENING CAREFULLY AS WE HAD SIMILAR CALL SIGNS. BOTH THE CAPT AND I CAN BE ASSURED THAT ATC CALLED 'ACR X AND NOT ACR Y.' AFTER ARRIVING IN PIT, I TALKED TO ZDC SUPVR WHO HAD NOT LISTENED TO THE TAPES YET BUT SAID THAT THEY (ZDC) HAVE BEEN HAVING TROUBLE WITH THE 2 CALL SIGNS FOR AWHILE. I SAID THAT I WOULD TALK TO DISPATCH TO SEE IF THEY COULD MAKE ANY MODIFICATIONS TO THE SIMILAR SOUNDING CALL SIGNS. AFTER HANGING UP WITH ATC, I CONTACTED DISPATCH, AS HE WAS AT THE DESK THAT ACR X WAS DISPATCHED FROM. HE NOTED THAT ACR Y DEPARTED PBI MINS BEFORE WE DEPARTED FLL AND HAD THE EXACT SAME RTE. HE MADE A NOTE TO HAVE THE CALL SIGNS ADJUSTED TO PREVENT FURTHER CONFUSION.

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.