What happened
On 26 October 1999, a Gazelle SA 342, registration F-GFDG, was conducting a private flight from a site in Nailsea toward Bristol Airport. The pilot intended to perform a downwind approach before turning into a westerly wind of approximately 8 knots. While executing the turn at an altitude of roughly 150 feet above ground level, the pilot experienced a loud bang accompanied by intense vibrations throughout the airframe. After a second loud noise, the vibration levels decreased. The pilot issued a 'Pan Pan' urgency call and successfully performed an emergency landing on the grass area near taxiway 'Golf'. There were no injuries to the two occupants.
The investigation
Following the incident, a post-flight inspection was conducted. Investigators found that both engine cowlings had been lost; these components were eventually recovered on and near the runway. The inspection also revealed superficial damage to all three main rotor blades, specifically noting that the leading edge protective strips had been torn. While the pilot initially suspected a bird strike, no evidence of such an impact was found on the aircraft. The investigation established that the helicopter had been in operation for three hours since its most recent pre-flight check.
Findings
- The failure of the forward locking device was the primary cause of the incident.
- The loss of the cowlings occurred during the turn toward the westerly wind.
- The aircraft sustained damage to the rotor blades and irreparable damage to the engine cowlings.