What happened
On 11 June 2011, an MD 900 Explorer, registration G-SASH, was performing a non-revenue commercial air transport flight from Leeds Bradford Airport to Bagby Airfield. The helicopter, operating as an air ambulance, had been placed on a specific landing spot by ground personnel. This spot was located upwind and approximately 18 metres away from the West Apron, where several light aircraft were parked.
As the pilot initiated a lift into a hover, the powerful downwash from the helicopter's rotors impacted a light aircraft parked nearby. This force caused the light aircraft to move, rotating 180 degrees. During this movement, the aircraft's port wing became wedged under the wing of another parked aircraft. The resulting contact caused minor damage to both light aircraft involved.
The investigation
Following the incident, the pilot and the Duty Airside Safety Unit Officer inspected the area. Both individuals confirmed that none of the light aircraft stationed on the West Apron had been chocked at the time of the occurrence. The investigation focused on the positioning of the helicopter and the lack of securing measures for the parked aircraft.
Findings
- The primary cause of the movement was the downwash generated by the helicopter during its transition to a hover.
- The light aircraft on the West Apron were not secured with chocks, allowing them to be displaced by the rotor wash.
Safety action
Since the event, Leeds Bradford Airport has reviewed its aircraft parking protocols. As a result of these changes, air ambulance helicopters are no longer permitted to use the West Apron area for positioning.