The pilots of a Sikorsky S-92A search and rescue helicopter were unaware, as they maneuvered toward a waypoint on the Irish coast in poor weather at night, that the waypoint was next to a 282-ft-high obstacle – a lighthouse and its surrounding terrain. The helicopter stuck the terrain and then plunged into the Atlantic Ocean, killing all four crewmembers.
In its final report on the March 14, 2017, crash of the CHC Ireland (CHCI) S-92A, the Irish Air Accident Investigation Unit (AAIU) identified the maneuvering, in combination with the crew’s lack of awareness of the obstacle, as the probable cause of the accident.
The report cited a dozen contributory causes, including that the location of the BLKMO waypoint was “almost coincident with the terrain”; that the operator’s activities in connection with “the adoption, design and review of its routes in the FMS [flight management system] Route Guide were capable of improvement in the interests of air safety”; and that the…
