History of the Flight
On 25 July 2019, the Sikorsky S-76C+ helicopter, registration EC-JES, departed for a night training exercise over the Vigo estuary near Cape Home. The flight was canceled due to fog and rescheduled for the following day. The training involved simulating a cliff rescue: a dummy was placed in the water, and a rescue swimmer was lowered by the winch operator to retrieve it.
On 26 July, the crew reported at 20:00 UTC and briefed on weather, maneuvers, and emergencies. The helicopter took off at 21:10 UTC from Vigo Airport and turned towards the estuary. During the flight, the crew switched roles so the co-pilot became the pilot flying.
As the helicopter descended to 500 ft to begin the exercise, the crew noticed the aircraft continuing to descend rapidly. They realized they were only 50 ft above sea level and executed an abrupt ascent maneuver, reversing the descent. The lowest altitude recorded was 22 ft above sea level.
Injuries and Damage
No occupants were injured, and the aircraft sustained no damage.
Investigation
The investigation by the Spanish Civil Aviation Accident and Incident Investigation Commission (CIAIAC) focused on the flight's procedures and crew actions. It determined that the incident resulted from a failure to adhere to proper procedures.
Probable Cause
The incident was caused by a failure to adhere to the proper procedures.
Safety Recommendations
The CIAIAC issued a recommendation to the operator, Babcock, proposing improvements to training on procedural adherence, response to warnings and alarms, and particularly CFIT (Controlled Flight Into Terrain) prevention during initial and recurrent crew training exercises.