Narrative:

On climb out, we were given a turn to 080 degrees. I read back 'left turn 080 degrees.' as we climbed, ATC advised that he gave us a right turn, then amended our heading to 190 degrees and altitude 8000 ft instead of the initial 15000 ft. The potential conflict was handled by ATC. Later, the captain informed me that he thought that the controller gave us a right turn but when I read back left turn and ATC didn't correct me, the captain assumed that I was correct and started the left turn. Problem: 1) ATC too busy to speak clearly. 2) my failure to understand. 3) captain didn't question what he thought he heard. 4) late night flying when I usually fly early morning. 5) ATC failure to listen to the pilot's readback.

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Original NASA ASRS Text

Title: READBACK OF CTLR'S INSTRUCTIONS WAS INCORRECT. PF FOLLOWED THE INCORRECT READBACK EVEN THOUGH HE QUESTIONED WHAT HE HEARD. CTLR HAD TO ISSUE AN AMENDED CLRNC TO CORRECT THE SIT.

Narrative: ON CLBOUT, WE WERE GIVEN A TURN TO 080 DEGS. I READ BACK 'L TURN 080 DEGS.' AS WE CLBED, ATC ADVISED THAT HE GAVE US A R TURN, THEN AMENDED OUR HDG TO 190 DEGS AND ALT 8000 FT INSTEAD OF THE INITIAL 15000 FT. THE POTENTIAL CONFLICT WAS HANDLED BY ATC. LATER, THE CAPT INFORMED ME THAT HE THOUGHT THAT THE CTLR GAVE US A R TURN BUT WHEN I READ BACK L TURN AND ATC DIDN'T CORRECT ME, THE CAPT ASSUMED THAT I WAS CORRECT AND STARTED THE L TURN. PROB: 1) ATC TOO BUSY TO SPEAK CLRLY. 2) MY FAILURE TO UNDERSTAND. 3) CAPT DIDN'T QUESTION WHAT HE THOUGHT HE HEARD. 4) LATE NIGHT FLYING WHEN I USUALLY FLY EARLY MORNING. 5) ATC FAILURE TO LISTEN TO THE PLT'S READBACK.

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.