Narrative:

On approach to phx -- visual to runway 26, at approximately 2000-1500 ft AGL, we lowered the landing gear. All appeared normal, however, the 'gear door' yellow annunciator light would not extinguish. We discussed a possible go around and recycled the gear. This time, the door light went out and we landed uneventfully. I assumed there was a spurious switch problem that corrected itself. We were scheduled for approximately 45 mins of ground time and we went about our preflight duties. Prior to the first officer doing his walkaround, the agent came on board and wondered if our mechanical would delay boarding. I wondered what mechanical he was talking about and he informed me that we had a gear door problem. I said it had fixed itself in the air and was no problem. About that time, a mechanic showed up and informed us that pieces were missing from the emergency lock on the right main gear door. Apparently, when we initially lowered the gear on approach, the bolt holding the latch in place was working itself out of position and would not allow the door to fully close. When we recycled the gear, the bolt and several washers and a nut had departed the aircraft (fortunately, we were over the salt river basin at the time and only snakes and lizards were put in harm's way). Without the broken parts preventing the locking of the gear door, it closed and indicated properly. It was held up by hydraulic pressure and sagged to the ground after the auxiliary hydraulic pump was turned off during the 'secure cockpit checklist.'

Google
 

Original NASA ASRS Text

Title: AN MD80, DURING LNDG GEAR EXTENSION, EXPERIENCED YELLOW R MAIN GEAR DOOR WARNING. RECYCLED LNDG GEAR CHKED OK. ON GND FOUND MISSING BOLT.

Narrative: ON APCH TO PHX -- VISUAL TO RWY 26, AT APPROX 2000-1500 FT AGL, WE LOWERED THE LNDG GEAR. ALL APPEARED NORMAL, HOWEVER, THE 'GEAR DOOR' YELLOW ANNUNCIATOR LIGHT WOULD NOT EXTINGUISH. WE DISCUSSED A POSSIBLE GAR AND RECYCLED THE GEAR. THIS TIME, THE DOOR LIGHT WENT OUT AND WE LANDED UNEVENTFULLY. I ASSUMED THERE WAS A SPURIOUS SWITCH PROB THAT CORRECTED ITSELF. WE WERE SCHEDULED FOR APPROX 45 MINS OF GND TIME AND WE WENT ABOUT OUR PREFLT DUTIES. PRIOR TO THE FO DOING HIS WALKAROUND, THE AGENT CAME ON BOARD AND WONDERED IF OUR MECHANICAL WOULD DELAY BOARDING. I WONDERED WHAT MECHANICAL HE WAS TALKING ABOUT AND HE INFORMED ME THAT WE HAD A GEAR DOOR PROB. I SAID IT HAD FIXED ITSELF IN THE AIR AND WAS NO PROB. ABOUT THAT TIME, A MECH SHOWED UP AND INFORMED US THAT PIECES WERE MISSING FROM THE EMER LOCK ON THE R MAIN GEAR DOOR. APPARENTLY, WHEN WE INITIALLY LOWERED THE GEAR ON APCH, THE BOLT HOLDING THE LATCH IN PLACE WAS WORKING ITSELF OUT OF POS AND WOULD NOT ALLOW THE DOOR TO FULLY CLOSE. WHEN WE RECYCLED THE GEAR, THE BOLT AND SEVERAL WASHERS AND A NUT HAD DEPARTED THE ACFT (FORTUNATELY, WE WERE OVER THE SALT RIVER BASIN AT THE TIME AND ONLY SNAKES AND LIZARDS WERE PUT IN HARM'S WAY). WITHOUT THE BROKEN PARTS PREVENTING THE LOCKING OF THE GEAR DOOR, IT CLOSED AND INDICATED PROPERLY. IT WAS HELD UP BY HYD PRESSURE AND SAGGED TO THE GND AFTER THE AUX HYD PUMP WAS TURNED OFF DURING THE 'SECURE COCKPIT CHKLIST.'

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.