Narrative:

Executed proper landing sequence. Followed checklist on downwind leg, base leg, and final approach. After touchdown landing gear lock failed causing landing gear to retract.

Google
 

Original NASA ASRS Text

Title: A MOONEY 20F LANDS AT RKP, TX, AND THE LNDG GEAR COLLAPSES AS THE LNDG GEAR LOCK HAD FAILED, ALLOWING THE GEAR TO RETRACT.

Narrative: EXECUTED PROPER LNDG SEQUENCE. FOLLOWED CHKLIST ON DOWNWIND LEG, BASE LEG, AND FINAL APCH. AFTER TOUCHDOWN LNDG GEAR LOCK FAILED CAUSING LNDG GEAR TO RETRACT.

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.