What happened
On December 17, 2011, two Eurocopter BO105 S helicopters, operating from the research vessel *Polarstern*, were involved in a sequence of accidents in the Atka Bay region of Antarctica. The day's operations included transporting personnel between the ship and the Neumayer-III station and ferrying scientists for ice drilling.
Following the delivery of researchers, the pilot of the first helicopter attempted a return flight to the station but aborted the mission due to whiteout conditions. The pilot returned to the second helicopter, which was parked on the sea ice. As weather conditions deteriorated with snowfall, the pilots decided to return to the *Polarstern*. After a brief period of waiting for improved weather, the pilots attempted a flight toward the ship but encountered further visibility degradation. They landed the two aircraft at a nearby penguin colony to wait for better conditions.
Upon seeing the ship and the station from the colony, the pilots attempted a final departure. During this flight, visibility dropped again, and ground references were lost. The pilot of the lead helicopter (No. 1) initiated an emergency landing. While attempting this, the following helicopter (No. 2) struck the ice surface hard, causing heavy damage. The lead helicopter subsequently attempted a turn toward the second aircraft, but its main rotor blades struck the ground, causing the aircraft to crash. The accident resulted in two persons slightly injured.
The investigation
The BFU investigation examined the operational procedures, flight planning, and meteorological conditions. The investigation found that the flight monitoring station on the ship's bridge was unmanned during the afternoon flights, contrary to established Standard Operating Procedures (SOP).
Furthermore, the investigation identified discrepancies in flight planning. Fuel calculations used a simplified method that did not fully comply with regulatory requirements for flying in hostile environments. Weight calculations for passengers were also found to be inconsistent with regulations, as they did not adequately account for the varying weights of personnel and survival gear. Additionally, the pilot of the lead helicopter was acting as the onboard flight operations manager without being formally designated as such in the company's SOPs.
Findings
The primary cause of both accidents was the loss of situational awareness due to whiteout conditions.
Contributing factors included:
- Rapidly deteriorating weather characterized by heavy snow showers.
- A featureless, snow-covered, and icy terrain that made visual references impossible.
- A lack of timely meteorological updates regarding the approaching weather front.
- The decision to continue the flight toward the ship despite having a safe landing option available in a more accessible area.