Narrative:

After takeoff; retracted gear; excessive vibration and noise from the nose gear area; extended gear; got 3 down and locked; declared an emergency; returned to ZZZ; landed without incident; ground crew had failed to close the forward gear doors on the nose landing gear.

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Original NASA ASRS Text

Title: UNKNOWN ACFT TYPE RETURNS TO DEP ARPT WHEN NOSE GEAR DOORS FAIL TO CLOSE ON RETRACTION DUE TO GND CREW ERROR.

Narrative: AFTER TKOF; RETRACTED GEAR; EXCESSIVE VIBRATION AND NOISE FROM THE NOSE GEAR AREA; EXTENDED GEAR; GOT 3 DOWN AND LOCKED; DECLARED AN EMER; RETURNED TO ZZZ; LANDED WITHOUT INCIDENT; GND CREW HAD FAILED TO CLOSE THE FORWARD GEAR DOORS ON THE NOSE LNDG GEAR.

Data retrieved from NASA's ASRS site as of January 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.