Narrative:

Our takeoff clearance included a turn to 180 degrees. I thought the clearance was to turn to 120 degrees and started a turn after takeoff. The first officer was busy cleaning up the airplane and did not notice I was turning. He noticed I was turning and said that the clearance was to a 180 degree heading. I reversed the turn as the tower controller said turn to 180 degrees. The tower had no other comment.

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Original NASA ASRS Text

Title: B757 ACFT, RPTR CAPT PF MISUNDERSTOOD HDG AFTER TKOF AND COMMENCED TURN. PNF FO NOTICED THE TURN AND CORRECTED THE CAPT AT THE SAME TIME THE TWR CTLR ADVISED FLC OF HDG.

Narrative: OUR TKOF CLRNC INCLUDED A TURN TO 180 DEGS. I THOUGHT THE CLRNC WAS TO TURN TO 120 DEGS AND STARTED A TURN AFTER TKOF. THE FO WAS BUSY CLEANING UP THE AIRPLANE AND DID NOT NOTICE I WAS TURNING. HE NOTICED I WAS TURNING AND SAID THAT THE CLRNC WAS TO A 180 DEG HDG. I REVERSED THE TURN AS THE TWR CTLR SAID TURN TO 180 DEGS. THE TWR HAD NO OTHER COMMENT.

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.