Inexperienced pilots, poor management and ineffective rules are endangering air travellers' lives in mountainous Nepal, aviation experts warned after the latest in a series of fatal accidents.
The comments came after the crash of an Agni Air plane on Monday, which killed 13 Indians and two Nepalese pilots.
Aircraft and pilots often have to contend with bad weather and difficult landing strips in the Himalayan country.
But Kul Bahadur Limbu, a retired pilot and former head of the national flag carrier, Nepal Airlines, said: "Like the country's other sectors, aviation suffers from lack of professionalism and leadership.
"There's also a cultural tendency not to strictly follow the rules. But in aviation, you can't deviate from the rules. Either you follow the rules or you don't -- there's no middle way.
"If you don't follow them, at some point, you will be caught, which could claim your life," he said.
His comments came following Monday's crash Monday near the high-altitude Jomsom airport, a gateway to the Annapurna mountain range, shortly after the pilot reported a fault.
It was the fifth fatal plane crash in less than two years in Nepal, which have claimed a total of 76 lives.
The frequency of accidents underscores the gap between the safety practices common in wealthy countries and those in Nepal, which only replaced radio guidance systems with radar in 1998.
The nation has a poor road network and large numbers of tourists, pilgrims and professional climbers often rely on the country's 16 domestic airlines and 49 airports to reach remote areas.
In 2008 the Initiative for Aviation Safety in Nepal (IASN), a lobby group promoting air safety, released a study which blamed the rising number of plane crashes in the country on 16 main factors.
Chief among them was a failure by government, the Civil Aviation Authority and airlines to implement recommendations proposed by accident investigation commissions.
"After every air crash the government forms a probe team. The team comes up with a report, which is never made public," said Limbu.
"Also, its recommendations for the concerned authorities are hardly ever implemented. Even if they do, they do it half-heartedly."
In its 2008 report the IASN concluded that a rapid increase in competition since the liberalisation of the industry in the 1990s -- opening up the skies to private airlines -- had not been accompanied by a rise in safety standards.
The group also warned that many aircraft were poorly maintained while runways across the country were dilapidated and flights often operated in bad weather and carrying excess weight.
"The government and air services operators have not been able to ensure flight safety. Both parties seem apathetic towards this issue," Toya Dahal, the author of the IASN report, said at the time.
"The trend of flying in hazardous weather and weak technical conditions must come to an end.
"There must be monitoring to ensure that aircraft are not flying under pressure in the name of business competition, and strict action must be taken against those found responsible for such actions."
Hemant Arjyal, an engineer and aviation analyst who is a member of the non-profit Nepal National Aviation Council, told AFP the industry was often dishonest in apportioning blame for fatal accidents.
"There is a tendency to blame the dead pilot," he said.
He conceded, however, that human error was a large factor in many of Nepal's plane crashes, with pilots -- often with little experience -- tending to be over-confident and even "adventurous" in the air.
"The mechanical systems will have enough back up," he told AFP. "But it's human beings who are responsible for the decisions that lead to crashes.
"Humans are the weakest link in the aircraft."