Narrative:

We operated into dtw and had a little over an hour sit before our flight out. After we shut down; the first officer got out to do his walk around; while I escorted an unaccompanied minor to the top of the jetway. After that I went and grabbed a cheeseburger. When I got back to the plane; the only people on board were the flight attendant and a check airman who was about to do my line check. Both were seated in the back of the aircraft. I went and sat in the main cabin as well. After a few minutes; an unidentified individual came on board and said we had an engine running. When I checked; the number two engine was running near idle. I shut it down immediately.

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Original NASA ASRS Text

Title: Air carrier Captain reported leaving the cockpit after parking the aircraft and realizing later one engine was left running.

Narrative: We operated into DTW and had a little over an hour sit before our flight out. After we shut down; the FO got out to do his walk around; while I escorted an unaccompanied minor to the top of the jetway. After that I went and grabbed a cheeseburger. When I got back to the plane; the only people on board were the FA and a Check Airman who was about to do my line check. Both were seated in the back of the aircraft. I went and sat in the main cabin as well. After a few minutes; an unidentified individual came on board and said we had an engine running. When I checked; the number two engine was running near idle. I shut it down immediately.

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.