What happened
On June 24, 2007, during the Salthill Airshow in Co. Galway, an EHI Merlin HC Mk 3, registration ZJ 137, experienced a component separation during departure. The aircraft, part of a military static display, was transitioning from a hover to a flight toward Galway Airport when an emergency egress hatch detached from the right-hand side cargo sliding door and fell to the ground.
As the crew began closing the sliding door during the flight transition, the unsecured hatch fell toward a beach area. The falling object caused two minor injuries to members of the public; one individual was struck by the hatch, while another was injured while attempting to evade the falling component. The pilot subsequently returned the aircraft to Galway Airport without further incident.
The investigation
The AAIU investigation focused on the condition of the hatch and the circumstances surrounding its detachment. Technical examination of the hatch revealed that the locking mechanism was functional and had been moved to the open/jertison position. Photographic evidence from the event confirmed that the hatch handle was in a closed position at 16:47 hrs but had been moved to the open position by 17:01 hrs, while the aircraft was on static display.
Investigators examined the security of the static display park, noting that while personnel from the Gardaí and Civil Defence were present, the public had significant access to the aircraft. The investigation also reviewed the pre-flight procedures performed by the flightcrew, specifically the external walk-around inspection conducted by the co-pilot.
Findings
- An unknown member of the public interfered with the hatch locking mechanism while the aircraft was on static display.
- The flightcrew failed to detect the unsecured hatch during their pre-flight walk-around inspection.
- The aircraft was subject to high volumes of public interaction, with approximately 400 people entering the cabin, making it difficult to prevent unauthorized contact with the exterior.
- The detachment occurred because the hatch was in the jettison position, allowing it to separate from the sliding door during flight maneuvers.
Safety action
Following the investigation, safety recommendations were made to the Joint Aviation Authorities (JAA) and the Irish Aviation Authority (IAA) to provide specific guidance regarding the protection of aircraft within static display parks, specifically addressing the need for barriers or cordons to prevent unauthorized interference.