Report on serious aviation incident on 24 February 2020 near the Maersk Invincible (XMKI) oil rig in the North Sea involving Sikorsky Aircraft Corporation S-92A, LN-ONT, operated by Bristow Norway AS
Aviation report 2024/03
The crew of the Sikorsky S-92A helicopter lost control of the helicopter shortly after take-off from the helipad on the Maersk Invincible oil installation. The departure was made in the dark and under demanding conditions where the crew had no external horizon or external visual references. On board was a crew of two pilots and nine passengers. The helicopter lost altitude, direction and speed. With a high nose up pitch, the helicopter accelerated backwards at a speed of 49 kt over a distance of 210 meters while losing further altitude. After approx. 40 seconds the crew regained control. The helicopter continued the flight to Stavanger Airport, Sola without further incidents. The Norwegian Safety Investigation Authority finds that the crew was probably exposed to spatial disorientation during take-off. Together with overcorrection of the flight controls, this caused the helicopter to leave the normal departure profile.
With no outside horizon and in the dark, both crew members were disoriented. Departures like this can be very demanding, and the importance of uncovering threats to a safe flight ahead of departure is very important. It will contribute to less stress for the crew, and help to ensure good internal communication.
As a result of the investigation, the Norwegian Safety Investigation Authority has advised two safety recommendations, one to the Norwegian Civil Aviation Authority and one to the helicopter operator. In its supervisory role with offshore helicopter operators, the Norwegian Civil Aviation Authority is advised to follow up their procedures and routines related to Threat and Error Management (TEM), TEM training and how TEM is managed in daily operations.
In the safety recommendation to Bristow Norway AS, the Norwegian Safety Investigation Authority advises the helicopter operator to implement "deviation call" for abnormal pitch variations for flights with passengers.
Published 15.02.2024
Safety recommendation
Safety recommendation Aviation No 2024/02T
The serious aviation incident on 24 February 2020 involving a Sikorsky S-92A, LN-ONT, occurred in the dark and in very challenging conditions where the crew had no external visual horizon or visual references. The pilots lost control of the helicopter during manual flying just after take-off from the Maersk Invincible oil rig as a result of disorientation and lack of situational awareness. Threat and Error Management (TEM) is currently described in the Expanded Checklist in the Operations Manual Part B. This investigation shows that the possibility of omitting important safety elements related to departure under particularly demanding conditions is still present. Active use of TEM in order to uncover threats to safe flight must be reflected in the daily operation.
The Norwegian Safety Investigation Authority (NSIA) recommends that The Norwegian Civil Aviation Authority (CAA-N) in its supervisory activities with offshore helicopter operators emphasize following up the operators' procedures and routines related to TEM, TEM training and how TEM is managed in daily operations.
Safety recommendation Aviation No 2024/03T
The serious aviation incident on 24 February 2020 involving a Sikorsky S-92A, LN-ONT, occurred in the dark and in very challenging conditions where the crew had no external horizon or visual references. The helicopter was flown manually, and, as a result of the pilot at the controls becoming disorientated, a situation arose with loss of control of the helicopter and a high pitch-up attitude. The Standard Deviation Calls do not include a deviation call for abnormal variations in pitch attitude. The NSIA considers that the absence of standard deviation calls for abnormal pitch variations can contribute to miscommunication and misunderstandings while seeking to re-establish a correct flight profile.
The Norwegian Safety Investigation Authority (NSIA) recommends Bristow Norway AS that the Standard Deviation Calls be extended to also include deviation calls for pitch variations that exceed predefined limit values.
Facts
| Location | Maersk Invincible (XMKI), Valhall oilfield, Norway |
| Occurrence date | 24.02.2020 |
| ICAO Location indicator | XMKI |
| Aircraft | Sikorsky øvrige |
| Operator | Bristow Norway AS |
| Registration | LN-ONT |
| Meteorological conditions | VMC |
| County | Annet/offshore |
| Type of occurrence | Serious incident |
| Type of operation | Offshore |
| Category of operation | Heavy, helicopter (> 2 250kg) |
| Aircraft category | Helicopter, Multi-engine, Turboprop/turboshaft |