United Airlines flight from Singapore to San Francisco is declaring an emergency.
The flight UA28, operated by a Boeing 787-9 (registration N27957) finally departed Singapore Changi Airport runway 20C at 21:35 SGT.
But less than one hour into the flight, the crew declared an emergency (squawk 7700) due to a technical issue with the aircraft.
UPDATE 14:50 UTC
The plane is holding 15,000 ft attitude being vectored back to SIN airport.
UPDATE 14:55 UTC
The airline is confirming to AIRLIVE the technical issue and scheduling a new departure in about 3 hours.
UPDATE 15:04 UTC (23:04 local time)
The aircraft has safely landed back at Singapore Airport runway 20C. It is taxiing to terminal 2, gate F42.
UPDATE 16:40 UTC
The flight is now cancelled, the Boeing 789 is out of service.
