Narrative:

We taxied out as a line of thunderstorms was passing the departure airport. During the starts and stops of the engines during the wait for takeoff on the west side; we were finally told to expect a departure to the southeast on the departure on the east side off 17. My first officer suggested we keep the APU running as we continued over to the other side and I agreed; as we would need it for the final engine starts. Shortly thereafter; they changed us back to the west side again on 18. In the reset process for this; the APU shutdown got over looked and missed again after takeoff on the cleanup checklist. I was the flying pilot enroute and the running APU was discovered later in the flight. It helped explain at that point the possible reasons for having burned more fuel; amongst our reroute and weather deviations on the flight. We of course shut it down immediately and kept it off till after landing. I continued to adopt further step climbs when able as we continued uneventfully our foreign destination. We continued to save fuel and found that the extra burn did not impact our endurance and divert options in a significant fashion. I plan of course as the flying pilot to increase my checklist backup in the future; and improve my scan of the overhead panel to assist the pilot monitoring; so I can avoid these types of omissions going forward. Thanks for taking the report.

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Original NASA ASRS Text

Title: An international B767 crew departed after multiple distractions caused by a weather related departure delay with engine shutdowns; then discovered after hours of flying that the APU had remained operating.

Narrative: We taxied out as a line of thunderstorms was passing the departure airport. During the starts and stops of the engines during the wait for takeoff on the west side; we were finally told to expect a departure to the southeast on the departure on the east side off 17. My First Officer suggested we keep the APU running as we continued over to the other side and I agreed; as we would need it for the final engine starts. Shortly thereafter; they changed us back to the west side again on 18. In the reset process for this; the APU shutdown got over looked and missed again after takeoff on the Cleanup Checklist. I was the flying pilot enroute and the running APU was discovered later in the flight. It helped explain at that point the possible reasons for having burned more fuel; amongst our reroute and weather deviations on the flight. We of course shut it down immediately and kept it off till after landing. I continued to adopt further step climbs when able as we continued uneventfully our foreign destination. We continued to save fuel and found that the extra burn did not impact our endurance and divert options in a significant fashion. I plan of course as the flying pilot to increase my checklist backup in the future; and improve my scan of the overhead panel to assist the pilot monitoring; so I can avoid these types of omissions going forward. Thanks for taking the report.

Data retrieved from NASA's ASRS site as of July 2013 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.