A Vietnam Airlines mistakenly hit the hijack button after a technical problem triggered an abnormal loss of cabin pressure on a recent short-haul flight, according to the Central Aviation Authority of Vietnam (CAAV).
“Black box and other data showed that this was a technical problem that did not involve terrorism in any way,” the agency’s director, Lai Xuan Thanh told the media on Saturday.
The flight left Ho Chi Minh City for the north-central town of Vinh on December 16, but was rerouted to Hanoi following its loss of cabin pressure.
Thanh said Vietnam Airlines technicians have conducted a test flight on the plane, an Airbus 321, to ensure it is safe to fly again.
The agency believes the captain falsely pressed the hijacking code (7500) instead of the emergency code (7700).
Thanh said the pilot corrected his mistake in a minute.
Thanh said his agency's investigation of the incident remains underway and could not rule out disciplinary action.
Earlier media reports quoted an unidentified source as saying that someone had tried to force his/her way into the cockpit, causing the pilots to reroute to Hanoi.
Vietnam Airlines issued a subsequent statement insisting that the emergency landing had nothing to do with a hijacking attempt.
The plane and its 135 passengers and seven crew members landed safely at Noi Bai at 7:15PM, according to Vietnam Airlines.
Of the 135 passengers, 26 remained at Noi Bai, while the others were transferred to another Vinh-bound flight that left at 9:40PM.
Vietnam Airlines currently operates three flights from HCMC to Vinh, the capital city of Nghe An Province, on a daily basis.
The flight in question was the last to take off that day at 5:10PM.
It was scheduled to land in Vinh at 6:55PM.