Kathmandu, Sept. 14 -- Nepal Airlines' only operational widebody aircraft was grounded in Japan on Monday after an engine problem disrupted its return flight to Kathmandu, further straining the state-owned carrier's international operations.

The Airbus widebody had been due to leave Narita at 10:30am local time and arrive in Kathmandu at 3pm. But the aircraft remained at Narita after a damaged blade was found on its No. 2 engine, leaving 226 passengers waiting for their flight arrangements to be resolved. The widebody aircraft had taken off from Kathmandu's Tribhuvan International Airport for Japan on Sunday at 11pm.

Nepal Airlines said one of the 26 blades in the engine had been damaged and the aircraft could not be cleared to fly unti...