Narrative:

Small transport aircraft training flight. Clearance was maintain runway heading off 36L and expect turn to 050 to V14. Safety pilot took clearance and was to work communications as was pilots request. As pilot I listened to clearance but planned to rely on safety pilot. After takeoff safety pilot switched seats with another pilot and the confusion began. Sound level was high at takeoff and I had not heard departure give me right turn but was expecting it. I was not aware that seat changing would take place on climb out. During this time heading deviated 20 degree right. Departure called and asked for my assigned altitude and heading. I wasn't sure but at this time expected that 360 was still assigned heading. I stated 360 degree assigned and our climb to altitude. Departure asked my current heading and I reported 'looking for a turn to 050.' departure again said state your heading and I stated 020. We were told to turn back to assigned heading and continue climb. I know of no evasive action taken. Contributing factors. Training flight. Poor coordination between pilot and safety pilot. Pilot relied on safety pilot for communication and should not have. High noise level at takeoff. Suggestions to prevent recurrence. Pilot must be prepared to be fully in command at all times. Maintain last assigned heading altitude until you are sure that it has been changed. If pilot is unclr, contact proper facility for clarification.

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Original NASA ASRS Text

Title: PLT ON AN IFR TRAINING FLT DEVIATED FROM ASSIGNED HDG ON INITIAL CLB OUT DUE TO COCKPIT DISTR AND EXTRA HIGH ACFT NOISE.

Narrative: SMT ACFT TRAINING FLT. CLRNC WAS MAINTAIN RWY HDG OFF 36L AND EXPECT TURN TO 050 TO V14. SAFETY PLT TOOK CLRNC AND WAS TO WORK COMS AS WAS PLTS REQUEST. AS PLT I LISTENED TO CLRNC BUT PLANNED TO RELY ON SAFETY PLT. AFTER TKOF SAFETY PLT SWITCHED SEATS WITH ANOTHER PLT AND THE CONFUSION BEGAN. SOUND LEVEL WAS HIGH AT TKOF AND I HAD NOT HEARD DEP GIVE ME R TURN BUT WAS EXPECTING IT. I WAS NOT AWARE THAT SEAT CHANGING WOULD TAKE PLACE ON CLBOUT. DURING THIS TIME HDG DEVIATED 20 DEG R. DEP CALLED AND ASKED FOR MY ASSIGNED ALT AND HDG. I WASN'T SURE BUT AT THIS TIME EXPECTED THAT 360 WAS STILL ASSIGNED HDG. I STATED 360 DEG ASSIGNED AND OUR CLB TO ALT. DEP ASKED MY CURRENT HDG AND I RPTED 'LOOKING FOR A TURN TO 050.' DEP AGAIN SAID STATE YOUR HDG AND I STATED 020. WE WERE TOLD TO TURN BACK TO ASSIGNED HDG AND CONTINUE CLB. I KNOW OF NO EVASIVE ACTION TAKEN. CONTRIBUTING FACTORS. TRAINING FLT. POOR COORD BTWN PLT AND SAFETY PLT. PLT RELIED ON SAFETY PLT FOR COM AND SHOULD NOT HAVE. HIGH NOISE LEVEL AT TKOF. SUGGESTIONS TO PREVENT RECURRENCE. PLT MUST BE PREPARED TO BE FULLY IN COMMAND AT ALL TIMES. MAINTAIN LAST ASSIGNED HDG ALT UNTIL YOU ARE SURE THAT IT HAS BEEN CHANGED. IF PLT IS UNCLR, CONTACT PROPER FACILITY FOR CLARIFICATION.

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.