Narrative:

On climb out before nikkl, we were assigned to climb to 14000 ft and maintain present heading (approximately 130 degrees). I was hand flying with the flight directors on and they were engaged in VNAV and H/south. As the aircraft approached nikkl, I followed the purple line and the copilot slewed the heading bug to match the purple line since both of us forgot about the assigned heading. After nikkl, there was an aircraft also on climb out which we noted on the TCASII. At that time, ATC called and asked us our heading. That is when we remembered what our clearance was. ATC then assigned us a 10 degree right turn and to maintain 14000 ft, which we did. This was pilot error, but aircraft safety was not compromised. In the future, I will be more aware of what I'm doing when the heading bug gets married up with the purple line.

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Original NASA ASRS Text

Title: A300 CREW, ON AN ASSIGNED HDG, TURNED TO COURSE DEPICTED ON SID.

Narrative: ON CLBOUT BEFORE NIKKL, WE WERE ASSIGNED TO CLB TO 14000 FT AND MAINTAIN PRESENT HDG (APPROX 130 DEGS). I WAS HAND FLYING WITH THE FLT DIRECTORS ON AND THEY WERE ENGAGED IN VNAV AND H/S. AS THE ACFT APCHED NIKKL, I FOLLOWED THE PURPLE LINE AND THE COPLT SLEWED THE HDG BUG TO MATCH THE PURPLE LINE SINCE BOTH OF US FORGOT ABOUT THE ASSIGNED HDG. AFTER NIKKL, THERE WAS AN ACFT ALSO ON CLBOUT WHICH WE NOTED ON THE TCASII. AT THAT TIME, ATC CALLED AND ASKED US OUR HDG. THAT IS WHEN WE REMEMBERED WHAT OUR CLRNC WAS. ATC THEN ASSIGNED US A 10 DEG R TURN AND TO MAINTAIN 14000 FT, WHICH WE DID. THIS WAS PLT ERROR, BUT ACFT SAFETY WAS NOT COMPROMISED. IN THE FUTURE, I WILL BE MORE AWARE OF WHAT I'M DOING WHEN THE HDG BUG GETS MARRIED UP WITH THE PURPLE LINE.

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.