Two aircraft nearly collided with the same helicopter over Reykjavik

Two aircraft in the traffic circuit at Reykjavik Airport crossed the flight path of the same helicopter about 10 seconds apart over Fossvogur, according to mbl.is. In the second incident, the aircraft came within 93 metres horizontally of each other.

The incidents are detailed in a final report by the Transportation Accident Investigation Board into a serious air traffic incident near Reykjavik Airport on August 2, 2024. The board said the tower controller likely lost track of the aircraft and, as a result, control of air traffic because of heavy workload.

The events began shortly after 1pm, when traffic at the airport was heavy. Two helicopters, OM-XWB and OM-TMH, were approaching for landing through Fossvogur valley while two planes, TF-FHI and TF-KFH, were in the circuit for runway 01. An air ambulance approaching from the north then requested priority to land on runway 13, requiring the controller to reorganise the sequence of approaches, take-offs and landings.

At 1:20:10pm, the pilot of TF-FHI told the controller that he had passed a helicopter at an altitude of 800 feet. The investigation found that about 10 seconds later, TF-KFH also came close to the same helicopter, OM-TMH, in almost the same location.

The exact distance between TF-FHI and the helicopter could not be established because the plane’s transponder was not operating. The helicopter pilot estimated that the plane crossed its path about 200 metres ahead, at around 1,100 feet, while the helicopter was at about 880 feet.

In the second incident, both aircraft had operating transponders, allowing investigators to estimate their separation using radar data. At their closest horizontally, they were 0.05 nautical miles, or about 93 metres, apart, with a vertical separation of 250 feet, or about 75 metres. At another point, their vertical separation fell to 175 feet, or about 53 metres, while they were 0.61 nautical miles apart.

Workload at the tower position was very high. The combined radio-frequency and telephone workload reached 97% during the seven minutes before the incident. The tower was fully staffed, with three controllers on duty: one at the tower position, one at the ground position and one resting in the tower room.

After the air ambulance requested priority, the controller struggled to reorganise traffic. He forgot to issue TF-KFH a landing clearance, and the plane went around after descending to about 20 feet above runway 01. He also twice confused the helicopters’ call signs and mixed up runways 13 and 31.

The pilots of the planes were not told about the helicopters approaching through Fossvogur valley, and the helicopter pilots were not told about the aircraft in the circuit. The controller said he initially thought the information did not need to be shared, but later had no time to do so.

The board said the controller’s limited experience, after about six months working in the tower, combined with a sudden and unusually heavy workload, likely led to the loss of control. The report also drew attention to equipment in the control tower.