Pulled the Wrong Lever – and Crashed into a Helicopter

Mount Everest brings Nepal around $300 million annually. Tourists from around the world travel to the country hoping to conquer the summit, paying $11,000 just for the climbing permit. That’s not including flights, hotels, guides, gear, and other expenses.

Let’s take a closer look at the flights. The journey to Everest runs through the small town of Lukla - often called “The Gateway to Everest.” Located at 2,860 meters above sea level, it is where most trekkers and climbers arrive from Kathmandu, Nepal’s capital, before continuing on foot toward the base camp - the starting point for the ascent.

Lukla Airport is one of the most challenging in the world. Its single runway is only 520 meters long. Due to the terrain, all landings are made on Runway 06, and all takeoffs on Runway 24. The runway has a steep gradient - the two thresholds differ in elevation by 60 meters. Runway 06 ends at a 700-meter cliff, while 24 faces a 4,000-meter ridge. The apron also has a helipad. All operations at the airport are visual only, as the only navigational aid is a basic radio station.

On April 14, 2019, a Summit Air L-410 Turbolet was preparing to depart from Lukla. The Let L-410 is well-suited for airports like this - it can take off from a 510-meter runway and land on a 500-meter one. However, the aircraft type has a poor safety record: 116 hull-loss accidents and 474 fatalities, largely due to its use in extreme and remote environments where other aircraft simply can’t operate.

There were only three crew members on board. This was the aircraft’s third flight of the day, transporting tourists and climbers from Ramechhap to Lukla.

The takeoff was being performed by the first officer. Just three seconds into the takeoff roll, the aircraft began veering to the right.

At that moment, an H125 helicopter operated by Manang Air was landing on the helipad. Its rotors were still spinning when the L-410 veered off the runway and slammed directly into it. The airplane hit the helicopter with enough force to flip it over. It then struck another helicopter parked on the apron before finally coming to a stop. The entire incident was caught on video.

The first officer, who was flying the aircraft, was killed upon impact with the spinning rotor blades of the helicopter. Two police officers responsible for the security of the helicopter’s passengers also lost their lives. The captain of the L-410 and the helicopter pilot sustained injuries. As previously mentioned, there were no passengers aboard the airplane. The passengers of the helicopter - including government officials - had already disembarked before the collision occurred.

In its final report, Nepal’s Aircraft Accident Investigation Commission determined that the accident was caused by the aircraft veering to the right during takeoff, which occurred due to the abrupt and unintended aft movement of the right power lever. This led to a thrust asymmetry. The captain’s attempt to correct the situation by increasing engine power did not yield the desired result. Additionally, asymmetric braking - caused by incorrect foot placement on the rudder pedals - further aggravated the rightward deviation.

Investigators were unable to determine the exact reason behind the sudden movement of the right power lever. One theory suggests that the first officer was not qualified to operate flights in and out of Lukla. According to Civil Aviation Authority of Nepal (CAAN) regulations, pilots must complete at least 100 short takeoffs and landings, have one year of flying experience in Nepal, and perform a minimum of 10 landings at Lukla under the supervision of a certified instructor. However, reports indicate that the first officer had at least 18 months of flight experience before the crash. Regardless, the commission specifically noted the first officer’s inability to quickly recognize and manage the situation, attributing it to a lack of sufficient experience.