KATHMANDU, Nepal (CNN) -- Pilot error caused the crash of a U.N. helicopter in March which killed 10 people, a Nepalese investigating official said Wednesday.
A U.N. worker at the site of the March helicopter crash that killed 10 people in Nepal.
The helicopter was traveling from a camp for former Maoist rebels in eastern Nepal to the capital, Kathmandu, when it crashed on March 3.
The crew did not consult the weather forecast, nor did it plan a route before taking off, said Nagendra Prasad Ghimire, the joint secretary of the civil aviation ministry and part of the investigation commission.
Once the helicopter encountered bad weather, the pilot's unfamiliarity of local terrain compounded the problem, Ghimire said, summarizing the commission's findings.
"He thought that, 'If I climb into the clouds, I will be safe above the terrain and continue to Kathmandu,'" he said.
Instead, the crew found itself unable to control the aircraft. But the pilot kept the helicopter on auto-pilot mode.
"The pilot should have manually handled the aircraft to rotate safely to the ground," Ghimire said. "Unfortunately, he didn't."
The chopper crashed in a mountainous region near Bhawasa, about 145 km (90 miles) east of Kathmandu.
The U.N. mission said three victims were Nepalese citizens. The others included four international arms monitors from Gambia, Indonesia, South Korea and Sweden.
The air crew, from a Russian company, comprised of two Russians and one Belarussian, the U.N. mission said.
The helicopter was returning from inspecting a camp for former Maoist rebels who fought a 10-year civil war to end Nepal's monarchy. More than 13,0000 people died in the fighting.
The rebels signed a peace deal with the government in 2006, joined mainstream politics and won the most seats in April's election for the Constituent Assembly.
The victory transformed Nepal from a monarchy to a republic after 239 years of autocratic rule.