History of Flight
On August 31, 2010, at approximately 0355 central daylight time, a Bell 206L-1 helicopter (registration N62AE) operated by Air Evac EMS, Inc. as Air Evac 30 was substantially damaged when it struck terrain following an in-flight breakup near Walnut Grove, Arkansas. The helicopter was on an emergency medical services positioning flight under Part 91. All three occupants—the pilot, a flight nurse, and a flight paramedic—were fatally injured. The flight departed from Vilonia, Arkansas, at 0335 en route to Crabtree, Arkansas, to pick up a patient.
The request for the flight originated from Van Buren County 911 dispatch at 0316:45. The dispatcher noted "crappy weather" in the county. After checking weather, the crew confirmed it was good, and the flight was dispatched at 0322:36. At 0339:35, the crew reported souls and fuel on board, an estimated time en route of 27 minutes, a planned altitude of 1,200 feet above ground level, and a risk assessment score of 15.
Radar data showed the helicopter climbing to between 2,000 and 2,600 feet mean sea level, with the last radar return at 0355:45 at 2,700 feet msl. The onboard GPS tracklog recorded the final position at 0355:52 at an altitude of 1,760 feet. The last minute of GPS data showed a series of turns: left, right, left, right, and a final left reversal. Skytrac data recorded the last position at 0354 at 1,800 feet and 119 knots ground speed.
Witnesses reported hearing rotor blade sounds, then a slowing of the blades, and sounds of an explosion and crushing metal. One witness reported seeing the helicopter circle overhead.
Wreckage and Impact
The accident site was located in forested, rolling terrain at an elevation of 585 feet msl. The main wreckage included the instrument panel, landing skids, engine, transmission, and cabin area, all damaged by impact forces and fire. A circular burn area extended north from the main wreckage. The main rotor mast was embedded about three feet diagonally in the ground.
The debris field started north of the main wreckage and extended southeast for half a mile to the main rotor assembly. The chin bubble was found 0.5 miles north at 930 feet msl. The main rotor assembly came to rest 715 feet northwest of the main wreckage at 611 feet msl. The white blade was inverted, with a tie-down strap wrapped around it, and exhibited multiple puncture holes and tears. The red blade also had puncture holes and scoring. The tail boom, consisting of the horizontal and vertical stabilizers, tail rotor driveshaft, and tail rotor assembly, came to rest 190 feet southwest of the main wreckage.
Examination of the flight controls revealed overload fractures in the main rotor non-rotating controls and the red pitch change link attach ear. The swashplate was found with the main wreckage. The throttle was found halfway between idle and full power. The engine showed no evidence of failure or malfunction prior to impact; boroscope examination revealed rotational impact damage consistent with the breakup.
Instrument panel indications included an inverted attitude indicator, airspeed 54 knots, heading 030 degrees, torque below zero, N1 at 126 percent, and N2 at 48 percent.
Personnel and Aircraft Information
The pilot, age 35, held commercial and airline transport pilot certificates with rotorcraft and instrument ratings. He had logged at least 3,312 hours in rotorcraft, including 489 hours in the accident make and model, and 311 hours in actual or simulated instrument conditions. He was hired by Air Evac in September 2007 and was the base pilot supervisor at Vilonia.
The helicopter was a Bell 206L-1 (serial number 45169), manufactured in 1978, powered by a Rolls-Royce 250-C30P engine. It was maintained under an approved inspection program. The last 150-hour inspection was completed on August 29, 2010, at 24,686.9 hours total airframe time. The helicopter had 24,689.5 hours at the time of the accident. It was equipped for instrument flight but not IFR certified; it had a radar altimeter and a night vision imaging system installed in July 2009, but no Helicopter Terrain Awareness Warning System.
Toxicological tests detected ethanol and other alcohols in the pilot's tissues, but the source does not attribute these to impairment or cause.
The emergency locator transmitter did not activate; its antenna cable had separated.