Narrative:

During climbout at about 10 minutes after departure while climbing through about 15;000 feet the captain noticed the same non-normal odor on the flight deck experienced two days prior. We called the mechanic who was on our jumpseat up to try and locate the source of the odor. After about a minute of not being able to locate the source of the odor; we sat the mechanic down and donned oxygen. It was apparent that the issue had not been fixed and a source of the odor could not be readily determined; we advised ATC. We are given a heading and a descent to return to ZZZ. As I was the pilot flying; the captain started working through 'smoke; fire or fumes' QRH and once completed; the descent and approach checklists. As we are in an expeditious descent as pilot flying; I had kept the speed at above 250 KIAS under 10;000 feet as a part of our authority to get the plane on the ground in the soonest amount of time. We set up for the ILS into ZZZ and were given vectors to the final approach course and tracked the ILS in for a normal landing. After touchdown; a right turnoff the runway was made and after the parking brake was set; the 'evacuation checklist' was completed. We vacate the aircraft via a set of mobile air stairs and wait as the fire crew clear the aircraft. During the postflight; the mechanic onboard deemed that the source of the odor was near the captain's overhead panel and possible from the wiring harness associated with the window heat system.

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Original NASA ASRS Text

Title: B767 flight crew reported experiencing a burning smell in the flight deck resulting in a return to the departure airport.

Narrative: During climbout at about 10 minutes after departure while climbing through about 15;000 feet the Captain noticed the same non-normal odor on the flight deck experienced two days prior. We called the mechanic who was on our jumpseat up to try and locate the source of the odor. After about a minute of not being able to locate the source of the odor; we sat the mechanic down and donned oxygen. It was apparent that the issue had not been fixed and a source of the odor could not be readily determined; we advised ATC. We are given a heading and a descent to return to ZZZ. As I was the pilot flying; the Captain started working through 'Smoke; Fire or Fumes' QRH and once completed; the descent and approach checklists. As we are in an expeditious descent as pilot flying; I had kept the speed at above 250 KIAS under 10;000 feet as a part of our authority to get the plane on the ground in the soonest amount of time. We set up for the ILS into ZZZ and were given vectors to the final approach course and tracked the ILS in for a normal landing. After touchdown; a right turnoff the runway was made and after the parking brake was set; the 'Evacuation Checklist' was completed. We vacate the aircraft via a set of mobile air stairs and wait as the fire crew clear the aircraft. During the postflight; the mechanic onboard deemed that the source of the odor was near the Captain's overhead panel and possible from the wiring harness associated with the window heat system.

Data retrieved from NASA's ASRS site 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.