Summit Air Flight 802D

Summit Air Flight 802D was a flight from Tenzing-Hillary Airport to Ramechhap Airport in Nepal. On April 14, 2019, the aircraft struck two Écureuil helicopters during takeoff. The aircraft veered off the runway and into an AS350 Écureuil by Shree Air and another Écureuil, by Manang Air. The collision resulted in the death of the Summit Air copilot and 2 security guards on the ground.^[1][2][3]

The aircraft involved was a Let L-410 with MSN 2914. The plane was manufactured in 2013.^[4]

The Let L-410 was scheduled for a positioning flight to Ramechhap Airport that day. The captain taxied the aircraft to the takeoff point of runway 24 and then handed over the controls to the first officer. The takeoff roll began at 9:07 a.m. After only three seconds, the aircraft veered sharply to the right, towards the Lukla Airport heliport. The Let's wing struck two security personnel who were directing aircraft at the heliport. As the aircraft taxied onto the heliport, a main rotor blade from a Manang Air Eurocopter AS350 9N-ALC ripped through the Let's cockpit, instantly killing the first officer. The aircraft then collided with the helicopter, and both fell to the level below the heliport, where a Shree Airlines Eurocopter AS350 9N-ALK was located. The first two aircraft were beyond repair, while helicopter 9N-ALK sustained only minor damage. The Let L-410 first officer and two people on the ground were killed.^[5][6][7]

The cause of the accident was determined to be a sudden veer to the right of the Let shortly after the start of the takeoff run, which was attributed to the fact that the right thrust lever had moved backward into idle during takeoff. The resulting thrust asymmetry caused the aircraft to veer off course. The cause of the faulty thrust lever position could not be determined. A contributing factor was the first officer's failure to recognize the thrust lever misalignment and react accordingly. This also left the captain, who was monitoring the flight, insufficient time to intervene. Furthermore, the captain's attempt to stop the veer by increasing engine thrust was unsuccessful. The subsequent braking maneuver, due to the pedal position, resulted in an asymmetrical braking action, which further contributed to the aircraft's veering off course.

• 2008 Los Roques Archipelago Transaven Let L-410 crash

• Final report
• Accident description at the Aviation Safety Network