Incident Overview
On an unspecified date, a Bell 206B JetRanger helicopter (serial number 381) landed at a private campground near Nordegg, Alberta. After landing, the pilot reduced the throttle to idle, tightened the cyclic and collective friction controls, and instructed the fixed-wing pilot seated in the left seat to hold the left-side controls steady. The helicopter pilot then exited the running helicopter and ran approximately 150 feet to a recreational trailer. While returning, he briefly spoke with the campground caretaker about 100 feet to the left of the helicopter.
Sequence of Events
Shortly after the conversation, witnesses heard a clunking sound similar to an out-of-balance washing machine, and the helicopter began to rock fore and aft on its skids. The main rotor disc appeared tilted to an extreme forward position. The pilot ran back, ducked under the main rotor disc from the left side, circled around the front, and climbed into the right seat. He attempted to stabilize the helicopter by applying collective and increasing rotor speed. The oscillations initially diminished but intensified when the skids lifted. The pilot then lowered the collective and shut down the engine. Applying the rotor brake after shutdown produced a loud clunk before the blades stopped.
Damage and Injuries
Examination revealed that the swashplate drive collar set and both main rotor pitch links were fractured. The transmission isolation mount, mount plate and support, and transmission pin assembly sustained overload damage consistent with severe mast bumping. The pitch horns on the rotating upper swashplate showed cowling contact damage. The collar set and pitch link fractures were overload in nature. None of the four occupants on board were injured.
Flight and Environmental Conditions
The flight, originating from Edmonton City Centre Airport, was to transport two Transport Canada officials and a dependent to multiple destinations for inspections. The stop at Nordegg was unplanned; the pilot chose to land at the campground to save time. Visual meteorological conditions prevailed with clear skies, unrestricted visibility, and light southerly winds. Temperature was estimated at 22 degrees Celsius.
Pilot Qualifications and Actions
The helicopter pilot held an Airline Transport Pilot Licence with 6,760 total hours, including 4,700 in rotorcraft and 943 in the Bell 206. He had previously exited running helicopters during training. The fixed-wing pilot, with 12,000 hours of fixed-wing experience, had no helicopter training and had not ridden in a Bell 206 for about 10 years. He reported pushing the cyclic forward during oscillations to prevent the helicopter from becoming airborne.
Regulatory Context
Canadian Aviation Regulations (CARs) 602.10 prohibit leaving an aircraft engine running unless a pilot seat is occupied by someone competent to control the aircraft. Exiting a running helicopter is considered acceptable by some pilots. The Transport Canada Helicopter Flight Operations Manual restricted control manipulation during flight to qualified pilots but did not address ground operations with rotors turning. An operational memorandum required a qualified pilot to occupy a seat with flight controls whenever the helicopter was running.
Helicopter Maintenance and Characteristics
The helicopter, originally a 1969 Bell 206A, had been upgraded to a Bell 206B JetRanger II. The mast assembly had been replaced about 15 hours before the incident; no pre-occurrence maintenance discrepancies were found. The Bell 206 features a semi-rigid, teetering, two-blade main rotor system. Mast bumping can occur if static stops contact the mast due to excessive blade flapping during ground operations. The cyclic and collective friction controls are not intended as control locks.