Background
A Norwegian military transport flight, operated by the Norwegian Air Force, was conducted from Harstad/Narvik Airport, Evenes, Norway, to Kiruna Airport, Sweden, as part of the Norwegian-led military exercise Cold Response. The aircraft, a C-130J-30 Super Hercules with call sign HAZE 01, carried a crew of four and one passenger.
Flight Sequence
HAZE 01 took off and climbed to Flight Level 130 (FL130), entering a holding pattern south of Evenes. After one hour, the flight continued towards Kiruna. Norwegian air traffic control (ATC) handed over the aircraft to Swedish ATC. Swedish ACC Stockholm cleared HAZE 01 to descend to FL100 “when ready” and instructed the crew to contact Kiruna Tower. The crew acknowledged and began descent from FL130. The lower limit of controlled airspace at this location was FL125. The aircraft entered uncontrolled airspace, and Kiruna Tower cleared HAZE 01 to FL70. Neither ACC Stockholm nor Kiruna Tower had radar contact with the aircraft because Swedish air navigation services lacked radar coverage at the altitudes involved.
Collision
HAZE 01 leveled at FL70 at 14:57 hrs. Half a minute later, the aircraft collided with terrain between the north and south peaks on the west side of Kebnekaise. The aircraft was in level flight at a ground speed of approximately 280 knots. Cockpit voice recorder and digital flight data recorder data showed the crew was unaware of the imminent danger of underlying terrain. The remaining distance to Kiruna Airport was 42 NM (77 km). All occupants sustained fatal injuries.
Investigation Findings
No technical malfunction caused or contributed to the accident. The investigation identified latent weaknesses both at the Norwegian Air Force and at LFV (the Swedish air navigation service provider). On the flight operations side, shortcomings existed in procedures for planning and following up a flight, combined with a probably high confidence in ATC, leading to the crew not noticing that the clearance required an altitude without adequate terrain separation. On the air traffic services side, clearances and flight information were not issued in accordance with applicable regulations due to insufficient experience and knowledge of the controllers. The lack of radar coverage reduced ATC’s ability to monitor and guide traffic. The Ground Collision Avoidance System did not activate because the terrain profile and settings did not meet warning criteria.
Rescue Operation
The rescue operation, characterized by very good access to resources from Sweden and abroad, lasted a relatively long time under extreme weather conditions in difficult alpine terrain. The investigation highlighted the need for further development in management, collaboration, and training.
Probable Cause
The accident was caused by the crew on HAZE 01 not noticing to the shortcomings in the clearances issued by the air traffic controllers and to the risks of following these clearances, which resulted in the aircraft coming to leave controlled airspace and be flown at an altitude that was lower than the surrounding terrain. The accident was rendered possible by the following organizational shortcomings in safety: - The Norwegian Air Force has not ensured that the crews have had sufficiently safe working methods for preventing the aircraft from being flown below the minimum safe flight level on the route. - LFV has not had sufficiently safe working methods for ensuring, partly, that clearances are only issued within controlled airspace during flight under IFR unless the pilot specifically requests otherwise and, partly, that relevant flight information is provided.