Narrative:

Controller frequency 132.52 issued our flight a heading for a climb from FL280 to FL310. While on this heading and climbing, I had to get out of my seat to check the security of the cockpit door. Prior to this, I had just come back from the cabin. I had some trouble locking the door so I got up to doublechk the lock. I gave the first officer control of the aircraft and the radio. While I was out of my seat, the first officer accepted a clearance and turned back toward the pxv VOR. When I got back into my seat the controller questioned our heading as if we were off heading. To my knowledge, there was no conflict with other traffic. We had no TCASII alerts. I don't know if my first officer accepted another aircraft's clearance or if the controller made an error.

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Original NASA ASRS Text

Title: AN ACR FLC FLYING AN MD80 NEAR PXV FAILS TO MAINTAIN ASSIGNED HDG AS INSTRUCTED BY ATC.

Narrative: CTLR FREQ 132.52 ISSUED OUR FLT A HDG FOR A CLB FROM FL280 TO FL310. WHILE ON THIS HDG AND CLBING, I HAD TO GET OUT OF MY SEAT TO CHK THE SECURITY OF THE COCKPIT DOOR. PRIOR TO THIS, I HAD JUST COME BACK FROM THE CABIN. I HAD SOME TROUBLE LOCKING THE DOOR SO I GOT UP TO DOUBLECHK THE LOCK. I GAVE THE FO CTL OF THE ACFT AND THE RADIO. WHILE I WAS OUT OF MY SEAT, THE FO ACCEPTED A CLRNC AND TURNED BACK TOWARD THE PXV VOR. WHEN I GOT BACK INTO MY SEAT THE CTLR QUESTIONED OUR HDG AS IF WE WERE OFF HDG. TO MY KNOWLEDGE, THERE WAS NO CONFLICT WITH OTHER TFC. WE HAD NO TCASII ALERTS. I DON'T KNOW IF MY FO ACCEPTED ANOTHER ACFT'S CLRNC OR IF THE CTLR MADE AN 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.