A computer problem forced All Nippon Airways Co. to cancel 53 domestic flights Sunday and delay more than 200 others, the airline said.
The glitch hit the computer system that controls reservations, check-in and baggage control at 50 airports nationwide, forcing ANA to handle those procedures manually.
The system was restored after 11 a.m., but some 51,000 passengers were expected to use other flights or get refunds before the day was over.
ANA said flights would be back to normal Monday.
Canceled flights included those from Haneda airport in Tokyo to Toyama, Osaka, Okayama, Hiroshima, Takamatsu, Fukuoka, Nagasaki and Miyazaki, ANA said.
The glitch also affected flights of Hokkaido International Airlines, known as Air Do, Star Flyer and Skynet Asia Airways, all of which depend on the ANA system.
The glitch was detected at around 4:40 a.m. when a Star Flyer employee launched the ticketing system.
The airline suspects that the problem was caused by a malfunctioning server. “I was supposed to take a flight at 9 a.m. to arrive (at Osaka) by noon because we have to attend a meeting with my sister’s fiance and his family members,” Toru Chochi, 28, a civil servant in Shinjuku Ward, Tokyo, who was at Haneda.
A 29-year-old salaried worker from Meguro Ward said, “My family is planning to stay in Nagasaki for one night. But we won’t be able to spend much time there” due to the flight delay.