The first non-stop flight between Australia and the UK has left Perth and is due to land in London on Sunday morning.
Qantas Flight QF9 should complete its 14,498km (9,009-mile) journey in just over 17 hours.
The airline is using the Boeing 787-9 Dreamliner, which is twice as fuel-efficient as the Boeing 747.
It is part of ambitious plans by Qantas to add ultra long-haul flights to its schedules.
Chief Executive Alan Joyce has called the new Perth-London service a “game-changing route”.
Speaking at an event ahead of the inaugural flight, he said the earliest Qantas flights between Australia and the UK – known as the “kangaroo route” – had taken four days and involved seven stops.
Western Australia’s state government is also hoping to see an increase in tourist numbers as a result of the new direct route.
The historic flight, carrying more than 200 passengers and 16 crew, departed from Perth at 18:49 local time on Saturday and is due at London Heathrow at 05:10 on Sunday.
To minimise the discomfort of such a long flight, the plane has been equipped with improved air quality and lower cabin noise.
Some of the passengers have agreed to share data on their sleeping and activity patterns with researchers from the University of Sydney.
They are wearing special monitors and devices that also record mental state, eating patterns and hydration, Sydney’s Daily Telegraph reports.
The flight will be the world’s second-longest after Qatar Airways’ route from Doha to Auckland, which spans 14,529km, according to the International Air Transport Association.
Other carriers, including Emirates and United Airlines, have also flown non-stop journeys greater than 14,000km.