Narrative:

Departing iad while being vectored to buffr intersection center issued a TA and then a climb from 7000 ft to 10000 ft. The captain had the traffic in sight. Since the aircraft was relatively light we had a higher than usual climb rate which resulted in a TCASII advisory to reduce climb. After passing well clear of the other aircraft, the controller asked if we were at 7000 ft. We advised that we had read back a clearance to 10000 ft. It seems likely that the controller had mistaken us for another company aircraft with a similar call sign. The controller then cleared the aircraft with the similar call sign to 10000 ft and cleared us on up to 17000 ft. The flight was completed uneventfully.

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Original NASA ASRS Text

Title: WDB ACFT GIVEN CLRNC INTENDED FOR SIMILAR A/N COMPANY ACFT. TCASII.

Narrative: DEPARTING IAD WHILE BEING VECTORED TO BUFFR INTXN CTR ISSUED A TA AND THEN A CLB FROM 7000 FT TO 10000 FT. THE CAPT HAD THE TFC IN SIGHT. SINCE THE ACFT WAS RELATIVELY LIGHT WE HAD A HIGHER THAN USUAL CLB RATE WHICH RESULTED IN A TCASII ADVISORY TO REDUCE CLB. AFTER PASSING WELL CLR OF THE OTHER ACFT, THE CTLR ASKED IF WE WERE AT 7000 FT. WE ADVISED THAT WE HAD READ BACK A CLRNC TO 10000 FT. IT SEEMS LIKELY THAT THE CTLR HAD MISTAKEN US FOR ANOTHER COMPANY ACFT WITH A SIMILAR CALL SIGN. THE CTLR THEN CLRED THE ACFT WITH THE SIMILAR CALL SIGN TO 10000 FT AND CLRED US ON UP TO 17000 FT. THE FLT WAS COMPLETED UNEVENTFULLY.

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.