Nepalese investigators have expressed concern over the potential risks of prematurely giving first officers operational experience at difficult airports, in their inquiry into a fatal accident at Lukla.

The first officer of an Aircraft Industries Let L-410 had been the flying pilot during a short take-off departure at Lukla last year. As the aircraft began to roll, a power differential between the engines led to an excursion and collision with a helicopter.

Nepal’s Aircraft Accident Investigation Commission says there is a “major challenge” arising from the desire by first officers to “master” difficult airports before they are authorised or ready for such operations.

“It was found that [first officers] have a tendency to request for such opportunities in order to be recognised among their co-workers, so as to be considered the first choice as a [first officer] for all senior captains,” says the inquiry.

Instructor pilots “rarely object” to these requests, it adds, especially if favourable conditions, such as good weather, are present.

“This sense of early achievement – which actually is dangerous – triggers a sense of satisfaction and feeling of confidence in [first officers],” says the inquiry.

It adds that these findings had “relevance” to the 14 April 2019 accident, involving a Summit Air flight, in which the first officer and two ground personnel suffered fatal injuries.

Lukla’s runway 24 is just 527m in length with an elevation of nearly 2,850m.

After the captain performed the taxiing and line-up on the departure runway, he handed control to the first officer, who initiated the take-off roll after just 15s.

But the inquiry says this time interval between the line-up and the roll was “not enough” for completing a handover.

Investigators had already made a number of recommendations in the aftermath of the accident, among them that captains should not hand control of departures or arrivals to first officers at short take-off and landing airports.