Narrative:

After takeoff from ZZZ; we were being vectored for our climb and were kept on a speed restriction. Climbing through about 17;000 feet; the speed restriction was removed and we heard a noise coming from the cabin. Soon; we realized [the] cabin door key had been left in the door. Noise lasted only a few minutes followed by an engine whine in the left engine. There were no other secondary indications. [We] chose to land in ZZZ1 which was only 15min away. Landed without incident.

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Original NASA ASRS Text

Title: Air carrier flight crew left key in door and it may have been ingested into left engine during cruise flight.

Narrative: After takeoff from ZZZ; we were being vectored for our climb and were kept on a speed restriction. Climbing through about 17;000 feet; the speed restriction was removed and we heard a noise coming from the cabin. Soon; we realized [the] cabin door key had been left in the door. Noise lasted only a few minutes followed by an engine whine in the left engine. There were no other secondary indications. [We] chose to land in ZZZ1 which was only 15min away. Landed without incident.

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.