Narrative:

ZDV issued clearance for aircraft X left 20 degrees pilot read back left 20 degrees and turned left 20 degrees. Center later asked what was our heading. We replied 042 degrees and said clearance was given to us to turn left 20 degrees. Center said clearance was for aircraft Y to turn left 20 degrees. We were then vectored 20 degrees to left then on course. No conflict was indicated by center, however, had he not noticed our deviation, a conflict would have arose. Controller should have warned us that a similar call sign was on frequency. Also, we read back clearance with full call sign and controller should have noticed error.

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Original NASA ASRS Text

Title: AN AIRBUS A320 FLC ACCEPTED A CLRNC INTENDED FOR A SIMILAR CALL SIGN ACFT.

Narrative: ZDV ISSUED CLRNC FOR ACFT X L 20 DEGS PLT READ BACK L 20 DEGS AND TURNED L 20 DEGS. CTR LATER ASKED WHAT WAS OUR HDG. WE REPLIED 042 DEGS AND SAID CLRNC WAS GIVEN TO US TO TURN L 20 DEGS. CTR SAID CLRNC WAS FOR ACFT Y TO TURN L 20 DEGS. WE WERE THEN VECTORED 20 DEGS TO L THEN ON COURSE. NO CONFLICT WAS INDICATED BY CTR, HOWEVER, HAD HE NOT NOTICED OUR DEV, A CONFLICT WOULD HAVE AROSE. CTLR SHOULD HAVE WARNED US THAT A SIMILAR CALL SIGN WAS ON FREQ. ALSO, WE READ BACK CLRNC WITH FULL CALL SIGN AND CTLR SHOULD HAVE NOTICED ERROR.

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.