An investigation by the Nepal government into the US-Bangla plane crash in Kathmandu has raised questions on the mental condition of the lead pilot of the aircraft. 51 people died after the Dhaka-Kathmandu US-Bangla Airlines aircraft clipped the fence at the Kathmandu airport and burst into flames. Both the pilots died in the crash. An investigation by the Nepal government suggests that the captain of the flight -- Abid Sultan -- lied to air traffic control (ATC) about carrying out the proper procedures for landing, was behaving erratically and was smoking continuously during the flight. The report also suggests the pilots seemed disoriented while landing and had lost sight of the runway.

Captain under immense stress The report, accessed by Nepali daily Kathmandu Post, suggests that Sultan was under immense mental stress and anxiety while flying the ill-fated ST211 plane that was carrying 71 passengers. His unusual behaviour during the flight should have raised immediate red flags, the investigation concluded. Among the troublesome behaviour investigators uncovered was captain Sultan lighting a cigarette three minutes before starting the plane's descent. Sultan also lied to the ATC about having locked down the plane's landing gears six minutes before making the final descent. The investigation report reportedly found that when the co-pilot conducted a final landing check, she found the gear was not down. Analysis of the conversation recorded by the cockpit voice recorder suggests that Sultan was suffering from stress. "He seemed to be fatigued and tired due to lack of sleep," the Kathmandu Post quoted the investigators as saying in their report. "He was crying on several occasions." The voice recorder also captured the conversation between Sultan and his co-pilot which suggests his turbulent state of mind. "I don't f---ing care about the safe flight, you f--- your duty," Sultan said at one point inside the cockpit, according to the report. Eventually, he also admitted he made a mistake to his co-pilot when the plane was starting to land. Sultan was also heard abusing a female colleague with whom he had a dispute throughout the hour-long journey.

History of depression A former Bangladesh Air Force pilot, Sultan had a history of depression, which was not reviewed by the US-Bangla airline when he was hired, Kathmandu Post reported. He had been removed from active duty in the Air Force after a psychiatric assessment in 1993 before he rejoined in 2002. However, medical assessments made during 2002-2018 did not indicate any mental health issues and found him fit for flying, the report also said.

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