Narrative:

We were on a flight from cvg to sfo, navigation was omega, backed with VOR. We were on a direct to coaldale. Center requested a 10 degree turn, then again cleared us to go direct to coaldale. The copilot was flying, and I changed my VOR to the next station, modesto. I was engaged in conversation with the so, and turned around not observing the flight path. The copilot made a turn to the right followed by a turn to the left. While we were in the left turn (approximately 270 degrees) center called and told us to make an immediate left turn to 210 degrees. Center also told another flight behind us to make an immediate right turn. We observed the TCASII and a target was to our right rear near the 10 mi mark. The first officer had made the turn to correct back on course, not realizing I had changed the VOR station. When I observed the flight path we were back on course. Center called us again and asked us why we made such an abrupt change in heading (approximately 65 degrees). I told the center we were correcting on course. Center stated in the future if we make that big a change in heading to notify them first. Contributing factors: long flight time, near the end of the flight. Complacency with a navigation system that was flying direct, and distraction in the cockpit with conversation. Failure to notify ATC of the turn.

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Original NASA ASRS Text

Title: FLC WAS AT FL350 AT CRUISE CLRED DIRECT TO A DISTANT VOR AFTER BEING GIVEN A MOMENTARY 10 DEG VECTOR CORRECTION AND MADE AN UNEXPECTED 65 DEG TURN TO THE R FOLLOWED BY A TURN BACK TO THE L. IMMEDIATE CORRECTIVE ACTION WAS REQUIRED BY THE ALERT CTLR TO PRESERVE THE SPACING WITH THE TFC IN TRAIL.

Narrative: WE WERE ON A FLT FROM CVG TO SFO, NAV WAS OMEGA, BACKED WITH VOR. WE WERE ON A DIRECT TO COALDALE. CTR REQUESTED A 10 DEG TURN, THEN AGAIN CLRED US TO GO DIRECT TO COALDALE. THE COPLT WAS FLYING, AND I CHANGED MY VOR TO THE NEXT STATION, MODESTO. I WAS ENGAGED IN CONVERSATION WITH THE SO, AND TURNED AROUND NOT OBSERVING THE FLT PATH. THE COPLT MADE A TURN TO THE R FOLLOWED BY A TURN TO THE L. WHILE WE WERE IN THE L TURN (APPROX 270 DEGS) CTR CALLED AND TOLD US TO MAKE AN IMMEDIATE L TURN TO 210 DEGS. CTR ALSO TOLD ANOTHER FLT BEHIND US TO MAKE AN IMMEDIATE R TURN. WE OBSERVED THE TCASII AND A TARGET WAS TO OUR R REAR NEAR THE 10 MI MARK. THE FO HAD MADE THE TURN TO CORRECT BACK ON COURSE, NOT REALIZING I HAD CHANGED THE VOR STATION. WHEN I OBSERVED THE FLT PATH WE WERE BACK ON COURSE. CTR CALLED US AGAIN AND ASKED US WHY WE MADE SUCH AN ABRUPT CHANGE IN HDG (APPROX 65 DEGS). I TOLD THE CTR WE WERE CORRECTING ON COURSE. CTR STATED IN THE FUTURE IF WE MAKE THAT BIG A CHANGE IN HDG TO NOTIFY THEM FIRST. CONTRIBUTING FACTORS: LONG FLT TIME, NEAR THE END OF THE FLT. COMPLACENCY WITH A NAV SYS THAT WAS FLYING DIRECT, AND DISTR IN THE COCKPIT WITH CONVERSATION. FAILURE TO NOTIFY ATC OF THE TURN.

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.