Eighteen hours aloft, covering more than 9,000 miles and crossing eight time zones: not an endurance test for air force personnel but the future longest commercial flight in the world, intended to start within two years.
Qantas plans to connect the UK non-stop with Australia by 2017, using the latest Boeing 787-9 to fly between London and Perth. The airline's chief executive, Alan Joyce, told Air Transport World that the new aircraft "opens up direct service from Australia to Europe for the first time", and indicated that a flight from Heathrow to the Western Australia capital would be the obvious choice.
In recent years Qantas has cut back its previously extensive European network, including a Heathrow-Perth route that stopped en route in Asia to refuel. It is believed the Australian airline has leased slots at Heathrow to British Airways, which could be reclaimed for the new service.
Qantas currently flies daily from Heathrow to Melbourne and Sydney, both via Dubai. The new London-Perth route would complement these links.
The ideal timing would be an early evening departure from Perth, arriving around noon next day in London - allowing plenty of time for connections at either end. The return flight would take off from Heathrow around 3pm, arriving late afternoon the next day in Perth.
Two pairs of pilots would be required for the flight, as well as extra cabin crew. The 787 will be fitted with a crew rest area above the passenger cabin.
The Australian airline holds the current record for the world's longest flight, with its daily Dallas-Fort Worth to Sydney service. The 8,579-mile trip takes 17 hours. Emirates plans to fly even further from February next year, with a Dubai-Panama City service covering 8,590 miles.
The London-Perth connection would prove navigationally challenging, involving diversions from the most direct route - which passes over the Crimea, currently off-limits to Western aircraft after last year's shooting down of Malaysia Airlines' flight MH17 with the loss of 298 lives.
The direct track also passes over the politically complex Caucasus and the Iranian city of Tabriz, before flying along India's western seaboard and over Sri Lanka to begin the Indian Ocean crossing.
Concerns have been raised about the need for diversionary airports in Western Australia, in case Perth is closed because of a storm. The nearest full-service international airport is Adelaide, a further 1,300 miles - or 2.5 hours flying time.
Experts have questioned the wisdom of opening such a route just at the time when Western Australia's economy is suffering because of a slump in commodity prices. The aviation analyst, John Strickland, said: "It's technically possible but commercially questionable. Much of the traffic would be price-sensitive leisure traffic which wouldn't give much of a return on using an expensive state-of-the-art aircraft."
Ultra-long-haul flights rely on a significant number of business travellers being prepared to pay a premium for a non-stop trip, thereby bankrolling the high fuel and staff costs involved.
British Airways, which currently flies from Heathrow to Sydney via Singapore, has the same "Dash 9" Boeing jet on order. The airline said: "We are always assessing our network and where we send aircraft."
Alan Joyce of Qantas has also speculated on a Melbourne-Dallas route, which would be almost exactly the same "great circle" distance as London-Perth. But because the vast majority of the route flies over the Pacific, it would be able to fly on the optimum track.
In it for the long-haul: Record non-stop jet flights through the years
May 1952 Rome-Beirut, BOAC Comet, 1,367 miles
October 1958 New York-London, BOAC Comet, 3,445 miles
June 1961 New York-Tel Aviv, El Al Boeing 707, 5,761 miles
August 1967 Madrid-Buenos Aires, Aerolineas Argentinas Boeing 707, 6,254 miles
December 1976 San Francisco-Sydney, Pan Am Boeing 747, 7,419 miles
May 1988 Tel Aviv-Los Angeles, El Al Boeing 747, 7,576 miles
June 2004 Singapore-New York, Singapore Airlines Airbus A340, 9,536 miles; route discontinued in 2013.
September 2014 Dallas-Sydney, Qantas Airbus A380, 8,579 miles
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