Narrative:

FAF for the ILS to 10 at msy, the gear was lowered and the 'gear down before landing' check was run by the first officer. The first officer checked the gear and found that the nose gear had an unsafe indication. We cycled the gear once and still had an unsafe nose gear. I notified tower as to the condition and went around. At this time an emergency was declared, and the first officer and I began to run the emergency checklist. In our aircraft 'be- 19OOD' the emergency checklist is very vague as to what should be done with an unsafe gear. It stated only to manually extend the gear. I decided that before we should attempt a manual gear extension that we should check for a more logical problem 'bad light bulb.' there are 2 additional ways to confirm that the gear is extended in a 1900, by the flaps to full or by retracting 1 throttle to idle. This was done and we did not get the gear warning horn. Thus confirming that the gear was down and locked. The aircraft was safely landed without incident. When the aircraft was deplaned, a mechanic found the landing gear to be safely locked in the down position. He later found that the whole landing gear light receptacle was bad.

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Original NASA ASRS Text

Title: FLC OF AN LTT DECLARED AN EMER AFTER THE NOSE GEAR UNSAFE LIGHT STAYED ON AFTER GEAR EXTENSION.

Narrative: FAF FOR THE ILS TO 10 AT MSY, THE GEAR WAS LOWERED AND THE 'GEAR DOWN BEFORE LNDG' CHK WAS RUN BY THE FO. THE FO CHKED THE GEAR AND FOUND THAT THE NOSE GEAR HAD AN UNSAFE INDICATION. WE CYCLED THE GEAR ONCE AND STILL HAD AN UNSAFE NOSE GEAR. I NOTIFIED TWR AS TO THE CONDITION AND WENT AROUND. AT THIS TIME AN EMER WAS DECLARED, AND THE FO AND I BEGAN TO RUN THE EMER CHKLIST. IN OUR ACFT 'BE- 19OOD' THE EMER CHKLIST IS VERY VAGUE AS TO WHAT SHOULD BE DONE WITH AN UNSAFE GEAR. IT STATED ONLY TO MANUALLY EXTEND THE GEAR. I DECIDED THAT BEFORE WE SHOULD ATTEMPT A MANUAL GEAR EXTENSION THAT WE SHOULD CHK FOR A MORE LOGICAL PROB 'BAD LIGHT BULB.' THERE ARE 2 ADDITIONAL WAYS TO CONFIRM THAT THE GEAR IS EXTENDED IN A 1900, BY THE FLAPS TO FULL OR BY RETRACTING 1 THROTTLE TO IDLE. THIS WAS DONE AND WE DID NOT GET THE GEAR WARNING HORN. THUS CONFIRMING THAT THE GEAR WAS DOWN AND LOCKED. THE ACFT WAS SAFELY LANDED WITHOUT INCIDENT. WHEN THE ACFT WAS DEPLANED, A MECH FOUND THE LNDG GEAR TO BE SAFELY LOCKED IN THE DOWN POS. HE LATER FOUND THAT THE WHOLE LNDG GEAR LIGHT RECEPTACLE WAS BAD.

Data retrieved from NASA's ASRS site as of July 2007 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.