Narrative:

We performed an emergency landing in mia because the gear could not be confirmed down and locked. When we realized the gear was unsafe we went around. We performed a series of tests and determined that the gear was down but the cockpit indicators still were 'unsafe.' I did a manual gear extension and still could not get the gear light to indicate down. I called our company and got advice from our maintenance. After they confirmed we did everything, we briefed the passenger. They prepared for an emergency landing. We called ATC and declared an emergency. Prior to this, we burned 1 hour of fuel to reduce the fuel. I landed on runway 9R in mia uneventfully and taxied to the gate. We later learned that a switch was dirty and prevented electrical contact.

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Original NASA ASRS Text

Title: A BEECH 1900D ON APCH FOR LNDG DECLARED AN EMER DUE TO L MAIN LNDG GEAR UNSAFE LIGHT ILLUMINATED CAUSED BY A FAILED L MAIN DOWNLOCK SWITCH.

Narrative: WE PERFORMED AN EMER LNDG IN MIA BECAUSE THE GEAR COULD NOT BE CONFIRMED DOWN AND LOCKED. WHEN WE REALIZED THE GEAR WAS UNSAFE WE WENT AROUND. WE PERFORMED A SERIES OF TESTS AND DETERMINED THAT THE GEAR WAS DOWN BUT THE COCKPIT INDICATORS STILL WERE 'UNSAFE.' I DID A MANUAL GEAR EXTENSION AND STILL COULD NOT GET THE GEAR LIGHT TO INDICATE DOWN. I CALLED OUR COMPANY AND GOT ADVICE FROM OUR MAINT. AFTER THEY CONFIRMED WE DID EVERYTHING, WE BRIEFED THE PAX. THEY PREPARED FOR AN EMER LNDG. WE CALLED ATC AND DECLARED AN EMER. PRIOR TO THIS, WE BURNED 1 HR OF FUEL TO REDUCE THE FUEL. I LANDED ON RWY 9R IN MIA UNEVENTFULLY AND TAXIED TO THE GATE. WE LATER LEARNED THAT A SWITCH WAS DIRTY AND PREVENTED ELECTRICAL CONTACT.

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.