NTSB Factual Report

On May 11, 2002, approximately 1900 central daylight time, a Bell 206B, single-engine helicopter, N717NH, impacted the terrain while maneuvering near Rosenberg, Texas. The helicopter was owned and operated by Jet Air, Inc., of Houston, Texas, under 14 Code of Federal Regulations Part 91. The airline transport rated pilot and three passengers received serious injuries, and one passenger received minor injuries. The helicopter sustained substantial damage. Visual meteorological conditions prevailed for the planned cross-country flight, and a flight plan was not filed. The flight was originating at the time of the accident.

The 11,000-hour pilot reported that after a south departure following a "normal takeoff" into the prevailing wind, he initiated a left turn at approximately 300 feet indicated altitude and felt "vibrations" and the next thing he remembered, "he was on the ground." The pilot did not claim any mechanical malfunction on the Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2).

The FAA inspector, who responded to the site, reported structural damage throughout the airframe of the helicopter.

The wreckage of the helicopter was conditionally released for recovery to the Air Salvage of Dallas (ASOD) facility in Lancaster, Texas, for further examination and evaluation. An examination of the fuselage revealed physical evidence consistent with downward compression and crushing with deformation left of the fuselage centerline. The left horizontal stabilizer exhibited physical evidence of ground impact, while the right horizontal stabilizer was not damaged. The tail boom was separated approximately one foot forward of the vertical fin.

Flight control continuity was established to the cyclic, collective and anti-torque control systems in the cockpit to the hydraulic servo actuators and tail rotor. The main rotor rotated freely and there was continuity at the hydraulic pump drive. One main rotor blade was bent aft and exhibited buckling. The top of the rotor mast was bent. The tail rotor gearbox was found separated from the mount and one tail rotor blade was separated at mid-span.

The integrity of the fuel lines and the PC air lines was not compromised and the torque stripes were not broken. Fuel was found in the airframe fuel filter as well as in the fuel lines. The fuel bladder was ruptured.

The caution light panel and the freewheeling unit were removed from the aircraft for examination at the Bell Helicopter facilities in Hurst, Texas. Examination of the free wheeling unit concluded that the outer shaft was fractured due to torsional overload. The torsional overload fracture and the condition of the sprag clutch with the inner and outer shafts were consistent with the sudden stoppage of the main rotor upon impact with the ground. Most of the bulbs in the caution panel appeared normal, with little or no aging of the filament. None of the filaments in any of the bulbs exhibited evidence of stretching.

The Rolls Royce Model 250-C20 engine, serial number CAE 270414 was removed from the airframe for examination. Foreign Object Damage (FOD) was found in the compressor section aft to the 4th stage. Continuity was established for N1 gas producer and N2 power turbine. The freewheeling unit was found seized and the drive shaft was found fractured. The inspection of the engine and engine components did not revealed any evidence of pre-impact failure.

The main fuel control and the power turbine governor were removed from the engine and shipped to the Honeywell facility in South Bend, Indiana, for further examination. Their testing revealed no anomalies that would result in a loss of power, flame-out, or sudden overspeed condition.

Examination of the maintenance records for the airframe and the engine did not reveal any overdue inspections or anomalies that could have precluded operation of the helicopter prior to the accident.

At 1853, the weather reporting facility at Sugarland, located approximately 17 nautical miles east of the accident site, reported the wind from 150 degrees at 13 knots, with scattered clouds at 5,00 feet. The temperature was 27 degrees Celsius (81 degrees Fahrenheit) and the dew point 22 degrees Celsius (72 degrees Fahrenheit). The altimeter setting was 29.98 inches of Mercury. The FAA inspector reported the wind was from the southeast at 15, gusting to 25 knots.

NTSB Probable Cause

The pilot's failure to maintain terrain clearance.