Narrative:

Climbing out between 10;000 and 12;000 feet I felt an impact from the captain's side of the flight deck with a loud boom. Assuming that we hit a bird at approximately 260 KIAS; I advised ATC turned on the autopilot; and returned. We smoothly landed over weight and returned to the gate without incident.

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Original NASA ASRS Text

Title: B737 flight crew reported a loud bang climbing through 10;000 feet. Assuming a bird strike the crew elected to return to the departure airport. Maintenance found an issue on the Captain's side window when they pressurized the aircraft to approximately 2.5 PSI which caused popping and flexing.

Narrative: Climbing out between 10;000 and 12;000 feet I felt an impact from the Captain's side of the flight deck with a loud boom. Assuming that we hit a bird at approximately 260 KIAS; I advised ATC turned on the autopilot; and returned. We smoothly landed over weight and returned to the gate 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.