Narrative:

During approach to an uncontrolled runway in VMC conditions, I performed a before landing checklist. This included rotating the manual gear handle to the 'up' position and locking it into place, therefore placing the gear down. On final, both my passenger (also a commercially-certified pilot) and I confirmed the security of the gear handle bar and the associated green light indication on the instrument panel that indicated a safe gear down condition. We continued the approach to the round out and flare and executed a smooth landing. We rolled for approximately 200-300 ft uneventfully. I then heard a muffled thump, accompanied by the aircraft continuing to settle to the runway. The propeller struck the ground and the engine encountered a sudden stoppage. The aircraft slid on the centerline for an additional 1000 ft and we egressed uneventfully. After shutdown, postflt inspection revealed the manual gear extension handlebar had popped out of its detent and had moved approximately 3/4 of its rotation toward the gear 'up' position. The aircraft was able to be jacked up to extend its gear and was towed to parking. The aircraft did not sustain substantial damage and was considered an incident.

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Original NASA ASRS Text

Title: MOONEY M20 GEAR FOLDED DURING LNDG ROLL DUE TO THE MANUAL GEAR ACTUATING BAR SLIPPING OUT OF ITS EXTEND POS DETENT.

Narrative: DURING APCH TO AN UNCTLED RWY IN VMC CONDITIONS, I PERFORMED A BEFORE LNDG CHKLIST. THIS INCLUDED ROTATING THE MANUAL GEAR HANDLE TO THE 'UP' POS AND LOCKING IT INTO PLACE, THEREFORE PLACING THE GEAR DOWN. ON FINAL, BOTH MY PAX (ALSO A COMMERCIALLY-CERTIFIED PLT) AND I CONFIRMED THE SECURITY OF THE GEAR HANDLE BAR AND THE ASSOCIATED GREEN LIGHT INDICATION ON THE INST PANEL THAT INDICATED A SAFE GEAR DOWN CONDITION. WE CONTINUED THE APCH TO THE ROUND OUT AND FLARE AND EXECUTED A SMOOTH LNDG. WE ROLLED FOR APPROX 200-300 FT UNEVENTFULLY. I THEN HEARD A MUFFLED THUMP, ACCOMPANIED BY THE ACFT CONTINUING TO SETTLE TO THE RWY. THE PROP STRUCK THE GND AND THE ENG ENCOUNTERED A SUDDEN STOPPAGE. THE ACFT SLID ON THE CTRLINE FOR AN ADDITIONAL 1000 FT AND WE EGRESSED UNEVENTFULLY. AFTER SHUTDOWN, POSTFLT INSPECTION REVEALED THE MANUAL GEAR EXTENSION HANDLEBAR HAD POPPED OUT OF ITS DETENT AND HAD MOVED APPROX 3/4 OF ITS ROTATION TOWARD THE GEAR 'UP' POS. THE ACFT WAS ABLE TO BE JACKED UP TO EXTEND ITS GEAR AND WAS TOWED TO PARKING. THE ACFT DID NOT SUSTAIN SUBSTANTIAL DAMAGE AND WAS CONSIDERED AN 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.