On September 9, 1997, at 0845 central daylight time, a Beech BE35-V35, N 9453S, owned and operated by a private individual under Title 14 CFR Part 91, departed runway 18 at the Sulphur Municipal Airport, Sulphur Springs, Texas, when the landing gear collapsed during the landing. The private pilot, sole occupant of the airplane, was not injured and the airplane sustained substantial damage. Visual meteorological conditions prevailed for the cross country flight and a flight plan was not filed for the flight that departed Paris, Texas, at 0800. Telephone interviews, conducted by the investigator-in-charge (IIC), revealed that the pilot performed several touch and goes at Cox Field, Paris, Texas, and then flew to Sulphur Springs where he performed a series of touch and goes to runway 36. During the final approach and landing on runway 18, the right main gear collapsed, the airplane turned 90 degrees to the runway, and the left main gear and the nose gear collapsed. The airplane departed the west side of the runway and came to rest in the grass. The flaps, propeller, fuselage, firewall, and landing gear received structural damage. The pilot was practicing short field landings for his Commercial Pilot Certificate. The pilot was scheduled with the FAA Designated Pilot Examiner at 0900 at Sulphur Springs for his commercial pilot certification flight. During personal interviews, and a review of the FAA Pilot Certification Records, the IIC gleaned that the pilot had failed his commercial pilot certification flight during two previous tries. On the first flight check, the airplane was 20 feet AGL before the pilot lowered the landing gear during a "simulated" emergency. During the second flight check, the short field landings were unsatisfactory. The FAA inspectors examined the airplane and found no discrepancies with the landing gear system. A mechanic, assisting the recovery of the aircraft, reported that when he entered the cockpit the gear handle was in the "down" position and the landing gear motor circuit breaker was "popped." When the mechanic turned on the master switch and pushed the circuit breaker "in," the gear motor ran for 2 seconds and the "green" gear down indicator light illuminated. All gear system components were intact and the landing gear was blocked over center for towing to the hangar. No electrical system discrepancies were found. During telephone interviews, conducted by the IIC, the witness, reported observing the airplane enter the pattern for runway 18. The right landing gear was not fully extended when the right wing struck the runway and the right inboard gear door scraped the runway. Subsequently, the left gear retracted and the left inboard gear door separated from the airframe.