The collision with electric lines was the cause of the helicopter accident that fought a fire in Sobrado, Valongo, Porto district, on September 5, 2019, causing the death of the pilot, Noel Ferreira, concluded the investigation.
The final report of the Office for the Prevention and Investigation of Aircraft Accidents and Railway Accidents (GPIAAF), to which the Lusa agency had access today, explains that, when approaching for the second water start, “when crossing an obstacle constituted by high voltage lines ”, the AS350-B2 bucket and tail rotor touched the cables, leading to loss of control of the device.
“The loss of control of the aircraft was inevitable and a consequent fall in rotation, covering a total distance of 84 meters until it immobilized on its left side, six seconds after the impact with the cables. After the collision with the ground, an intense fire immediately broke out and consumed the aircraft in its entirety. The pilot and sole occupant of the aircraft was fatally injured, ”says GPIAAF.
Noel Ferreira, 36, was also a pilot of the Portuguese Air Force at Squadron 751, based in Montijo, which operates the EH-101 helicopter in search and rescue missions, and also commander of Cete’s Voluntary Firefighters, in Paredes, district of Porto, which, “at the time of the accident, was among others, fighting the fire on the ground”.
The Eurocopter took off at 15:10 from a private Afocelca base (Navigator group) in Valongo, Porto district, with a team of five firefighters and the fire-fighting equipment consisting of a basket and bucket. After dropping the intervention team on the ground, and the bucket having been positioned, the pilot flew to a nearby water point for the first supply and discharge in the fire.
The cycle repeated, in the second approach to the fire and in coordination with another aerial medium that operated on the spot, “the pilot, aware of the existence and location” of the electric lines, “defines the trajectory for the second start”.
“After crossing a very duly signaled first line of very high voltage, composed of 14 conductors, the aircraft and the suspended bucket collided with a second line. This second line, composed of 8 conductors, was positioned at a lower level and about 45 meters from the first horizontal distance, ”says the report.
The lines on which the helicopter crashed were not signposted, but the investigation notes that, “in view of the current regulations, such signage is not a requirement, since they were in the area of influence of another higher signposted line”.
After the collision, without a tail rotor or vertical stabilizer, the device “started an uncontrolled flight until it collided with the terrain”.
“The pilot’s body was found 5 meters to the right of the cockpit seat, (…), a situation that could not have resulted from the fall or the explosion, thus evidencing its autonomous movement after the fall”, concluded the researchers.
According to the report, the pilot recorded 180 hours of total flight time experience on the AS350-B2 model, mostly in firefighting operations, in which he participated since 2018.
In terms of risk assessment, GPIAAF underlines that, in view of the physical scenario and the verified conditions, “it cannot be excluded that another additional factor contributed to the accident, namely that the pilot felt one or more of the types of pressure characterized in a ICAO circular – International Air Transport Organization: mental pressure resulting from the operation, motivational pressure and peer pressure ”.
“As the pilot was fighting a fire by air when on the ground was a corporation of volunteer firefighters, in which, in addition to sharing the spirit of mission and a companionship relationship, there was also a hierarchical connection where the pilot was the commander of this corporation, it cannot be excluded that there could be, to a certain degree, a propensity to devalue or relativize the risks, in search of the best success in the rapid fire domain ”, points out the report.
However, according to the researchers, “the mental attitude with a focus on flight conditions is decisive in the necessary and constant risk assessments required of a pilot with the numerous threats presented in the experienced scenario, especially in flight situations where there are no concrete rules and strict performance, as is the case with these operations with airlines ”.