HISTORY OF FLIGHT On October 5, 1997, at 1220 central daylight time (cdt), an Aero Commander 100-180, N4028X, registered to Auburn Flying Services, Inc., of Auburn, Nebraska, was destroyed during a collision with a moving semi-tractor trailer and terrain, while on short final approach to runway 20 (1600' X 100' dry/sod) at Farington Field, Auburn, Nebraska. The commercial pilot sustained serious injury and the three passengers sustained fatal injuries. The personal 14 CFR Part 91 flight was not operating on a flight plan. Visual meteorological conditions prevailed at the time of the accident. The flight departed Farington Field, Auburn, Nebraska at 1210 cdt. According to an eyewitness, the airport was sponsoring a pancake fly-in that morning of the accident. The pilot had been giving rides to people throughout the morning. The pilot flew a total of ten flights. He landed on runway 16 for seven of the flights, and landed on runway 20 for the two flights just prior to the accident. During the last approach to runway 20, the airplane collided with a semi-tractor trailer traveling west on highway 136, impacting the truck's sleeper compartment. The airplane's tail section was entangled in a backhoe the semi-tractor trailer was carrying on the trailer, while the rest of the airplane came to rest on the threshold of runway 20. A second eyewitness said, the "...plane made its approach, it was too low." According to a second eyewitness, he heard the noise of a semi-tractor trailer cresting the hill behind him on highway 136. He turned to look and saw N4028X on final approach to runway 20. Out of the corner of his eye he watched N4028X flare and saw the truck, which had a high backhoe on the trailer, drift directly into the path of the airplane. The tail section of the airplane struck the high wind deflector on the truck cab, slid back, and was caught by the John Deere backhoe. The airplane fractured behind the passenger compartment and the balance of the airplane (passengers, wings, engine, etc.) continued over the road and onto the grassy area at the end of runway 20. The runway is sod. The airplane, minus the empennage, struck the ground and rolled over several times ending upside down. OTHER DAMAGE A semi-tractor trailer registered to Drillon Trucking Company received damage to the sleeper berth. The John Deere backhoe on the trailer received minor damage. PERSONNEL INFORMATION The pilot was born December 17, 1920. He was the holder of a commercial pilot certificate with single/multi engine land ratings. The pilot also held an instructors rating. He also held a second class medical issued on October 18, 1996. A review of the pilot's last logbook revealed his most recent biennial flight review was on July 23, 1997. He had accumulated a total of 15,710 hours of flight time. AIRCRAFT INFORMATION The airplane was an Aero Commander 100-180, serial number 5128, N4028X. The airplane had accumulated 3,912 hours time in service at the time of the accident. The engine had 1,587 hours total time in service. The most recent annual inspection was conducted on June 19, 1997, 21 hours prior to the accident. WRECKAGE AND IMPACT INFORMATION The NTSB on-scene investigation began at 1130 cdt on October 6, 1997. The main wreckage was found on the over run area to runway 20 in an inverted position, approximately 60 feet from the highway. The engine had separated from the firewall and was lying next to the main cabin area. Both wings remained attached to the main cabin with numerous bends and wrinkles to the leading edges. The empennage and tail section aft of the passenger compartment area was removed from the John Deere backhoe. The empennage was wrapped around the front of the backhoe. The sleeper section of the truck had evenly spaced slash marks. Both propeller blades had chord wise scrapes. Flight control continuity was confirmed. The engine, engine controls, and all other airplane systems revealed no anomalies. ADDITIONAL DATA A Party to the investigation was the Federal Aviation Administration. Following the on-scene portion of the investigation, the wreckage was released to a family member on October 6, 1997.