On March 4, 2002, at 1235 central standard time, a Bell 206L-3 single-engine helicopter, N227H, was substantially damaged during a forced landing to a road following a total loss of engine power while on approach to a company helipad near Tulsa, Oklahoma. The commercial pilot and his passenger were not injured. The helicopter was owned and operated by Tulsa Security Patrol Inc., d.b.a. Action Helicopter Services of Tulsa. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 positioning flight. The flight originated from Tulsa's Richard Lloyd Jones Jr. Airport, approximately 1230, and was en route to the company helipad. The pilot reported that the flight was en route to the helipad for fuel when the engine lost power approximately 300 yards short of the helipad. During an autorotation to a road, the pilot had to execute an evasive maneuver to avoid a vehicle. Subsequently, at 10 feet agl, the main rotor blades struck 1.5 inch-diameter tree branches. The main rotor RPM decreased, the helicopter landed hard on the road, and the main rotor blades contacted and severed the tail boom. The pilot estimated 300 pounds of fuel was on board at the time of the accident. On March 14, 2002, at a facility in Tulsa, an FAA inspector, the operator's director of maintenance, and the pilot examined the helicopter. Prior to the FAA inspector's arrival, the main rotor blades and main rotor mast had been removed. During the inspection, the engine was started and test run to idle speed, and no anomalies were noted. The fuel nozzle and fuel filters were inspected, and no anomalies were noted. The reason for the loss of engine power was not determined.