Though Nepal's air industry has boomed in recent years, carrying goods and people between hard-to-reach areas as well as foreign trekkers and climbers, it has a poor safety record. Nepal's aviation industry has long been plagued by poor safety due to insufficient training and maintenance. The European Union has banned all Nepali airlines from its airspace over safety concerns.

from Times of India https://timesofindia.indiatimes.com/world/south-asia/plane-crashes-in-nepal-over-the-years-claim-hundreds-of-lives-a-timeline/articleshow/91868696.cms