Hélicopters - 2022

In 2022, the BEA published eight reports regarding occurrences during helicopter operations. These reports concern seven accidents and one serious incident.

The published reports deal with eight different types of helicopter, including two twin-engine helicopters. All seven helicopters involved in the accidents were destroyed. One accident and the serious incident took place during a dark night. 

• Three occurrences highlight the fact that some private pilots did not take into account or even lacked knowledge of the characteristics and performance limitations of rotorcraft.
• Two reports address the risks that pilots may take given the manoeuvring possibilities of helicopters when flying in the vicinity of obstacles or terrain.
• Two reports highlight organisational weaknesses in companies carrying out commercial air transport and aerial work.

In these seven accidents, nine people were fatally injured, two were seriously injured and five were injured.

1. Lack of knowledge of helicopter characteristics and performance

In 2022, as in previous years, three investigations showed a lack of knowledge of phenomena specific to rotorcraft (especially unanticipated yawing) and failure to take into account the differences in helicopter performance between flat land flight and mountain flight.

The accident to F-GFHA on 17 August 2021 at Fleurey-sur-Ouche illustrates a safety theme already identified in the previous year’s thematic reviews (2021 review): the pilot failed to counter a right yaw during a low speed turn. Although he could not remember the accident flight precisely, the pilot indicated that he was not familiar with the yaw effect, although it has been described in numerous publications which are mentioned in the report. He linked this yaw with a loss of tail rotor effectiveness. He did not apply the correct emergency procedure for this but made ill-adapted inputs on the rudder pedals with respect to direction, amplitude and duration to regain control of the helicopter.

In two accidents, the pilots flew at the operating limits of their aircraft without being aware of the available power margins. In the accident to F-HAGO on 12 January 2021 at Bastelica, the pilot flew at low height over a pass situated at an altitude of 7,200 ft. He then found himself on the leeward side of the terrain, under the effect of a downdraft. At this point, the pilot did not have sufficient reserve power to counter this effect. He was then obliged to make a forced landing on the slope. In the accident to F-HPIC on 2 March 2021 at Les Gets, the pilot chose to carry out a yaw take-off from a mountain helicopter landing surface in an environment restricted by numerous obstacles and with a helicopter close to its maximum permissible weight, which offered a low reserve power for take-off. The pilot quickly decided to abort the take-off and during the forced landing manoeuvre, he was unable to avoid a power line and a billboard.

A more thorough study of the helicopter's performance before take-off might have alerted the pilots of the risks.

Two people were seriously injured in the occurrences mentioned.

2. Risks associated with flying near obstacles or terrain

Helicopters give pilots the possibility of flying in restricted spaces and of landing in confined areas, often surrounded by obstacles. Whether for leisure or for professional purposes, pilots must always keep in mind that this freedom of movement is subject to risk.

In the accidents to F-GIBM on 7 March 2021 at Touques and to F-GKTR on 13 May 2021 at Planaise, the pilots knew their environment, nevertheless they hit obstacles they were aware of. The pilot of F-GIBM had to perform a skilful safe vertical climb close to obstacles. This type of manoeuvre offers few safety margins. In the second case, the pilot knowingly chose to fly close to obstacles, to limit the risk of spraying product on the nearby motorway and he hit the power line that he had nevertheless previously spotted.

The accident to F-HUBA on 9 February 2021 at Planay showed dangerous manoeuvres unnecessary for normal flight management. The pilot flew at low height over a ridge with a small safety margin. The BEA regularly observes accidents resulting from similar risk-taking. The analysis of these occurrences brings to light that one of the motivations leading a pilot to carry out this type of manoeuvre is to put on a sort of “show” for third parties, passengers for example.

In the events mentioned, four people were fatally injured, one was seriously injured and three were injured.

3. Organizational weaknesses

Two published reports involving two twin-engine helicopters provide numerous safety lessons specific to helicopters, though the factors behind the occurrences are not limited to just them.

The near-collision with the surface of the water of F-GYLH on 11 February 2021 off Le Havre was the result of an error in the selection of the autopilot mode during a short, routine, single-pilot flight on a dark night. The lack of monitoring of flight parameters during a phase of flight with a high workload, the non-application of procedures, which can be explained by the fact that they were not sufficiently adapted to the reality of the operation, as well as the low salience of the warning signals have been identified as possible contributing factors.

The accident to F-HJAF on 8 December 2020 at Bonvillard was a collision with vegetation, also on a dark night, during low-height operations in the mountains. This collision at night could be explained by the pilot’s loss of situational awareness regarding the position of the helicopter in relation to the terrain. Partial or total loss of visual references due to deteriorating weather conditions and reduced light on a dark, moonless night was identified as a contributing factor.

Night flight, compared to day flight, increases the pilot’s  exposure to certain risk factors such as degraded visual performance, visual aberrations and spatial disorientation. This information is described in the DSAC (French civil aviation safety directorate) guide "Night VFR in helicopters" (in French).

In both reports, organisational factors appear to have contributed to the occurrences. In particular, the workload linked to the accumulated duties or the low experience of some of the crew members are highlighted. In the incident to F-GYLH, the operator's safety management system had identified internal weaknesses that had only been partially addressed by the operator and the oversight authorities. In the accident to F-HJAF, the investigation showed that the risks of the flight in relation to the night flight experience of the crew to be trained were underestimated.

In the occurrences mentioned, five people were fatally injured and one was seriously injured.