Accident Summary
On 26 February 2019, a Bell 412 helicopter, registration EC-MAQ, operated by Babcock MCS España S.A.U., executed an emergency landing on the Narcea River near Llongoria, Asturias. The helicopter was engaged in aerial firefighting operations in the Belmonte area. The crew, consisting of two pilots, had completed a first two-hour flight period and was beginning a second period. During a water refill from a pool in the Narcea River where the channel splits, the tail rotor contacted vegetation as the helicopter inadvertently drifted backward. Upon detecting the contact, the pilot-in-command reduced power and performed a level touchdown on the riverbed, where the water depth was approximately one meter.
Aircraft and Crew
The helicopter was a Bell 412, registration EC-MAQ. It was owned and operated by Babcock MCS España S.A.U. The crew comprised two pilots; the flight was conducted as a single-pilot operation with two pilots on board. Both occupants were uninjured and evacuated the aircraft unaided.
Accident Sequence
The helicopter had been deployed from its base at Tabuyo del Monte (León) to assist in extinguishing a forest fire near Belmonte, Asturias. On the day of the accident, the crew was beginning the second flight period. They selected a water source different from the one used in the first period: a pool in the Narcea River where the river split into two branches. After arriving at the location, they performed a test water load and released it at the same hover point. During the second water load, the crew did not notice that the helicopter had drifted backward, resulting in the tail rotor blades contacting nearby vegetation.
Damage
The helicopter sustained substantial damage to the tail rotor, main rotor, transmission shaft, and landing skids.
Cause
The investigation determined that the accident was caused by the incorrect execution of a water refill maneuver over a water course, motivated by the lack of adherence to procedures.