What happened
The pilot was performing the downwind leg for runway 35 when the landing gear was lowered. According to the pilot, all systems appeared normal during the approach; however, upon touchdown, the landing gear retracted.
Following the retraction, the aircraft slid approximately 250 yards along the runway before coming to an upright stop. A post-accident fire subsequently erupted, which consumed the cockpit area, the instrument panel, and the belly of the airframe. No injuries were reported.
The investigation
The investigation focused on why the gear failed to remain extended. The pilot noted that the gear did not lock in the down position. Per the Pilot's Operating Handbook, a green light on the instrument panel below the landing gear switch is intended to indicate that all gears are down and locked. Additionally, the landing checklist requires pilots to verify that the green light is on, the warning horn is off, and the emergency handle is in the forward position when speeds are under 150 MPH.