Narrative:

After takeoff; the landing gear was up and locked but loud noise was heard (suspect nose gear doors did not close). Prior maintenance had worked on landing gear but wrote could not duplicate. Flew at slow speed under 200 kts to ZZZ (longer runway and maintenance and better crash fire rescue equipment). Declared an emergency; did all emergency related checklists even though no checklist for this problem. Put gear down before landing and did a fly-by by the tower so ATC and our own maintenance could see down and locked condition. Landed without incident.

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Original NASA ASRS Text

Title: Loud noise following gear retractions leads EMB-140 flight crew to suspect the nose gear doors failed to close. Declare emergency and divert to another airport for maintenance.

Narrative: After takeoff; the landing gear was up and locked but loud noise was heard (suspect nose gear doors did not close). Prior maintenance had worked on landing gear but wrote could not duplicate. Flew at slow speed under 200 kts to ZZZ (longer runway and maintenance and better Crash Fire Rescue equipment). Declared an emergency; did all emergency related checklists even though no checklist for this problem. Put gear down before landing and did a fly-by by the Tower so ATC and our own maintenance could see down and locked condition. Landed without incident.

Data retrieved from NASA's ASRS site as of May 2009 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.