What happened
On 30 July 2024, a Bell 505 Jet Ranger X, registered N57NC, was conducting flight training near Killucan, Co. Westmeath. The aircraft, operated by an Approved Training Organisation, was carrying an instructor and a student pilot. The flight was intended to prepare the student for a type rating skills test.
During the flight, the crew performed a series of maneuvers known as practice autorotations. Data indicates that the helicopter had successfully completed five such maneuvers before the accident occurred during a sixth attempt. At approximately 14:25 UTC, the helicopter impacted an agricultural field. Following the initial impact, the aircraft traveled forward, cleared a boundary fence, and struck the gable wall of an agricultural building, coming to rest in the structure's roof and wall. Both crew members sustained fatal injuries.
The investigation
The AAIU examined the wreckage and recovered digital data from the aircraft's Garmin G1000H integrated avionics system. The investigation established that the aircraft's flight path followed the M4 motorway before the fatal maneuver.
Physical examination of the wreckage revealed significant structural damage, including a fractured main rotor mast and a separated tail rotor gearbox. The engine had separated from the main and tail rotor drive shafts, and the tailboom was loosely attached to the fuselage. Investigators also noted that the 'Fly/Idle' switches on the collective levers were in different positions: the instructor's switch was in 'Fly' while the student's was in 'Idle'. There was no evidence of engine malfunction or power loss prior to the impact.
Findings
- The accident occurred during the execution of a sixth practice autorotation maneuver.
- The aircraft sustained severe structural failure, including the separation of the engine from the drive shafts and the fracturing of the main rotor mast.
- The weather at the time of the accident was clear, sunny, and dry, with high visibility.
- The student pilot had recently completed a Private Pilot Licence (H) and had only a few hours of experience on this specific helicopter type.