What happened
On 29 May 2022, a Tara Air Twin Otter (D/HC-6/300), registration 9N-AET, was scheduled for several flights between Pokhara and Jomsom. Due to earlier weather-related closures at Jomsom Airport, multiple aircraft from both Tara Air and Summit Air were operating in the area. At 0410 UTC, 9N-AET departed Pokhara with 19 passengers and 3 crew members on board.
Prior to departure, the pilot expressed hesitation regarding the flight due to unfavorable weather reports received from a preceding Summit Air aircraft, 9N-AKZ. However, following pressure from ground staff or passengers and the departure of a subsequent Summit Air flight, the aircraft took off. During the climb, the crew reported passing Ghodepani and climbing toward 12,500 feet. Upon contacting Jomsom Tower, the pilot inquired about wind conditions, noting high southwesterly winds of up to 30 knots.
As the flight progressed, the aircraft encountered heavy cloud cover. Cockpit voice recordings indicated that the pilot was attempting to navigate through brighter areas to avoid clouds. During these maneuvers, the aircraft's Terrain Avoidance and Warning System (TAWS) was inhibited. The aircraft eventually struck rocky terrain at an altitude of 4050 meters AMSL on Sanusare Mountain in the Thasang Rural Municipality. The impact resulted in 22 fatalities and the total destruction of the aircraft.
Findings
Investigation into the accident identified several contributing factors:
- The flight crew failed to monitor their course correctly while flying in instrument meteorological conditions (IMC).
- The operation was conducted with the TAWS inhibited during deteriorating weather.
- There was a significant loss of situational awareness among the crew members.
- The pilot in command performed all cockpit duties, including both flying and monitoring, which impaired performance.
- Factors such as high crew gradient, poor crew resource management (CRM), and the underutilization of navigation instruments were noted.
- External pressures to depart despite unfavorable weather reports contributed to the sequence of events.