Narrative:

During climb out flight attendant reported a loud 'rushing air' noise coming from main cabin door 1L. Cockpit indications were all normal. After inspection by cockpit crew it appeared that the main cabin door was improperly closed on the ground. Right side interior main cabin door hinge cover was out of place not allowing the cabin door to properly seal. Coordinated with dispatch to return to ZZZ so maintenance technicians could inspect door. After returning to ZZZ; maintenance found door to have been improperly closed. Corrective action: close door properly; no further action required. After discussion with dispatch and maintenance technicians; aircraft was refueled; re-released; new [maintenance document] signed-off; and proceeded to ZZZ1 without further incident.

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Original NASA ASRS Text

Title: B737 Captain reported Flight Attendant reported air leak at cabin Main Entry Door after takeoff.

Narrative: During climb out Flight Attendant reported a loud 'rushing air' noise coming from Main Cabin Door 1L. Cockpit indications were all normal. After inspection by cockpit crew it appeared that the main cabin door was improperly closed on the ground. Right side interior main cabin door hinge cover was out of place not allowing the cabin door to properly seal. Coordinated with Dispatch to return to ZZZ so Maintenance Technicians could inspect door. After returning to ZZZ; Maintenance found door to have been improperly closed. Corrective action: close door properly; no further action required. After discussion with Dispatch and Maintenance Technicians; aircraft was refueled; re-released; new [Maintenance document] signed-off; and proceeded to ZZZ1 without further 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.