20210424006649A

Aircraft departed from runway 23 at approximately 15:30Z from ucp en-route to TSO. At about 10 miles north of the airfield, pilot began decent to traffic pattern from 4500 ft by reducing power down to 17 inches of manifold pressure to slow airspeed to flap operating range. After crossing over the airport at midfield to enter a left downwind for runway 25, he applied a first notch of flaps. Once established on a left downwind position in the traffic pattern, pilot stated he lowered the gear handle and verbally called gear down. Due to traffic reported in the area, he looked outside the cockpit to look for the traffic approaching the field and does not recall checking to see if he had the gear down and locked indicated. After assessing everyones position and distance from the field, he announced turning base legs over the UNICOM and added second notch of flaps, then adding the final notch of flaps as he turned final. While descending over the runway threshold at approximately 105 mph he stated he did not recall any difference in handling of the aircraft or the stall horn warn going off until making contact with the ground. The aircraft then rode the propellers and underside of the aircraft down the centerline of the runway until the plane came to a full stop. At that time, he stated a lite cloud of smoke appeared underneath the left yoke. He then turned the fuel shutoff, magnetos, and master switch to the off position and evacuated the aircraft along with his passengers.