Australia's Qantas operates 19 hour London-Sydney flight

Australia's national carrier Qantas on Friday successfully completed a 19-and-a-half hour non-stop flight from London to Sydney, which was used to run a series of tests to assess the effects of ultra long-haul flights on crew fatigue and passenger jetlag.

The Boeing 787-9 Dreamliner took off from London's Heathrow Airport on Thursday morning and touched down at Sydney Airport 45 minutes behind schedule at 12:30pm on Friday.

The 17,800 mile (11,060 mile) journey was part of Project Sunrise Qantas' goal to operate regular, non-stop commercial flights from Australia's east coast cities of Brisbane, Sydney and Melbourne to London and New York.

Last month, Qantas completed the first non-stop flight from New York to Sydney, which took 19 hours and 16 minutes.

Another New York to Sydney flight is expected next month to round out the project.

There were 52 people mostly Qantas employees on board. They participated in various experiments, including using wearable technology devices to track sleep patterns, food and drink intake, lighting and physical movement.

A final decision on whether the ultra-long haul flights will become a commercial reality is expected by the year's end, with the service potentially launching by 2022.

It was the second time a commercial airline has flown the route. The first was in 1989, with a journey time of 20 hours and 9 minutes.

Ahead of the flight, Qantas chief executive Alan Joyce said the airline wants to improve comfort on long-haul flights.

"We know that travelers want room to move on these direct flights, and the exercises we encouraged on the first research flight seemed to work really well," he said.

"So, we're definitely looking to incorporate on-board stretching zones and even some simple modifications like overhead handles to encourage low impact exercises, he added.

Joyce and Australian Prime Minister Scott Morrison welcomed the arrival of crew and passengers as the airline celebrates its centenary year.