Narrative:

Just crew onboard B737-800; first officer closed the boarding door and informed cabin crew we were ready to go. I was in the cabin; went to my left forward entry (L1) door and made announcement to flight attendants to 'arm' doors and cross check. Immediately after take-off a loud air noise was immediately noticed. First officer (who was apc riding in passenger cabin) went to cockpit to notify them. We turned around and landed back at the departure airport. First officer re-opened/closed door; per procedures; door had to be inspected. All checked out ok. We took off for our destination without problem with the door.defect in boeing door [design] that cockpit door warning indicator doesn't show if door is not properly closed; if problem is in the aft section of the door; was how it was explained to me.

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Original NASA ASRS Text

Title: The Flight Attendant in charge reports their B737-800 aircraft required an air turn-back due to a loud air noise coming from Forward Entry Door 1-Left immediately after takeoff. A First Officer had closed the door prior to departure. Flight Attendant noted the cockpit Door Warning Indicator did not show door was not properly closed.

Narrative: Just crew onboard B737-800; First Officer closed the boarding door and informed cabin crew we were ready to go. I was in the cabin; went to my Left Forward Entry (L1) Door and made announcement to flight attendants to 'Arm' doors and Cross Check. Immediately after take-off a loud air noise was immediately noticed. First Officer (who was APC riding in passenger cabin) went to cockpit to notify them. We turned around and landed back at the departure airport. First Officer re-opened/closed door; per procedures; door had to be inspected. All checked out OK. We took off for our destination without problem with the door.Defect in Boeing door [design] that cockpit Door Warning Indicator doesn't show if door is not properly closed; if problem is in the aft section of the door; was how it was explained to me.

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.