Narrative:

My crew and I were on final to sfo runway 28R in a dassault falcon 20. Upon extending the landing gear, I noticed that there was only 2 of 3 green down and locked indications. After testing the circuit, I realized that it could be a burnt out bulb, at which time I elected to do a go around to do checklist procedures. After landing and having maintenance verify the problem, it turned out to be a burnt bulb, at which time the mechanic replaced the bad bulbs with new ones and returned the aircraft to service.

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Original NASA ASRS Text

Title: A DASSUALT FALCON 20 RECEIVED 2 GEAR DOWN LIGHTS AND FOLLOWED PROCS WITH A NORMAL LNDG.

Narrative: MY CREW AND I WERE ON FINAL TO SFO RWY 28R IN A DASSAULT FALCON 20. UPON EXTENDING THE LNDG GEAR, I NOTICED THAT THERE WAS ONLY 2 OF 3 GREEN DOWN AND LOCKED INDICATIONS. AFTER TESTING THE CIRCUIT, I REALIZED THAT IT COULD BE A BURNT OUT BULB, AT WHICH TIME I ELECTED TO DO A GAR TO DO CHKLIST PROCS. AFTER LNDG AND HAVING MAINT VERIFY THE PROB, IT TURNED OUT TO BE A BURNT BULB, AT WHICH TIME THE MECH REPLACED THE BAD BULBS WITH NEW ONES AND RETURNED THE ACFT TO SVC.

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.