Narrative:

I made a normal approach to landing in light wind conditions. There was no indication of a problem during the approach. I put the landing gear in the down position when I was approximately 2 mi west of the field. The indicator showed that the gear was extended fully. I entered a left downwind for runway 35 and completed the prelndg checklist for the second time when I turned a 1.5 mi final approach. I turned final at 550 ft AGL, the gear was down, the mixture was full rich, the propeller speed was full forward, and I was operating off the left main fuel tank. I flew the final approach just above the VASI GS and touched down at the 1000 ft markers. Everything seemed normal at touchdown and I was in the process of removing the last of the engine power when a buzzer sounded briefly. I then realized that the plane was beginning to settle to the runway. I held the nose of the plane up for as long as possible as the plane slid on the runway. I do not know what caused the landing gear to fold up, but am certain that the wheels touched and the plane began to roll before the gear folded. While I touched down at the 1000 ft marker and the plane progressed another approximately 500 ft, there was only about 30-50 ft of skid/scrape on the pavement. The plane came to a rest right side up with each of the main gears still partially extended. There were no injuries. A number of witnesses mentioned, after the incident, that the landing appeared to be normal until the plane fell to the runway. The circuit breaker for the landing gear motor was blown after the incident.

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Original NASA ASRS Text

Title: ACFT EQUIP PROB. LNDG GEAR COLLAPSED AFTER LNDG.

Narrative: I MADE A NORMAL APCH TO LNDG IN LIGHT WIND CONDITIONS. THERE WAS NO INDICATION OF A PROB DURING THE APCH. I PUT THE LNDG GEAR IN THE DOWN POS WHEN I WAS APPROX 2 MI W OF THE FIELD. THE INDICATOR SHOWED THAT THE GEAR WAS EXTENDED FULLY. I ENTERED A L DOWNWIND FOR RWY 35 AND COMPLETED THE PRELNDG CHKLIST FOR THE SECOND TIME WHEN I TURNED A 1.5 MI FINAL APCH. I TURNED FINAL AT 550 FT AGL, THE GEAR WAS DOWN, THE MIXTURE WAS FULL RICH, THE PROP SPD WAS FULL FORWARD, AND I WAS OPERATING OFF THE L MAIN FUEL TANK. I FLEW THE FINAL APCH JUST ABOVE THE VASI GS AND TOUCHED DOWN AT THE 1000 FT MARKERS. EVERYTHING SEEMED NORMAL AT TOUCHDOWN AND I WAS IN THE PROCESS OF REMOVING THE LAST OF THE ENG PWR WHEN A BUZZER SOUNDED BRIEFLY. I THEN REALIZED THAT THE PLANE WAS BEGINNING TO SETTLE TO THE RWY. I HELD THE NOSE OF THE PLANE UP FOR AS LONG AS POSSIBLE AS THE PLANE SLID ON THE RWY. I DO NOT KNOW WHAT CAUSED THE LNDG GEAR TO FOLD UP, BUT AM CERTAIN THAT THE WHEELS TOUCHED AND THE PLANE BEGAN TO ROLL BEFORE THE GEAR FOLDED. WHILE I TOUCHED DOWN AT THE 1000 FT MARKER AND THE PLANE PROGRESSED ANOTHER APPROX 500 FT, THERE WAS ONLY ABOUT 30-50 FT OF SKID/SCRAPE ON THE PAVEMENT. THE PLANE CAME TO A REST RIGHT SIDE UP WITH EACH OF THE MAIN GEARS STILL PARTIALLY EXTENDED. THERE WERE NO INJURIES. A NUMBER OF WITNESSES MENTIONED, AFTER THE INCIDENT, THAT THE LNDG APPEARED TO BE NORMAL UNTIL THE PLANE FELL TO THE RWY. THE CIRCUIT BREAKER FOR THE LNDG GEAR MOTOR WAS BLOWN AFTER THE INCIDENT.

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.