Imagine spending more than 20 hours on a single flight, without getting off and stretching your legs.
It is not an exciting prospect, but Australian passengers who want to get to London more quickly will have the option of the marathon flight, under a plan hatched by Qantas chief executive Alan Joyce.
The non-stop Sydney to London flight would be the longest commercial route in the world and would take 20 hours and 20 minutes. In exchange, passengers will get to London almost four hours sooner because there will be no need to stop and refuel in the Middle East.
Joyce wants to offer the non-stop flights to London as well as non-stop flights to New York by 2022.
The one impediment to the plan is that there are currently no planes that could make the journey when fully laden with passengers and luggage. Joyce is challenging Boeing and Airbus to develop the aircraft within the next five years.
The aircraft manufacturers are already close.
In fact, in April next year Qantas will launch the first ever direct flight between Australia and Europe, when it begins flying direct from Perth to London, a 17 hour journey.
It shows how far air travel has come - when Qantas created the Kangaroo Route to London in 1947, it took four days and nine stops.
April's launch will give the airline the chance to see what sort of passenger demand there is for such long flights.
The Kangaroo Route - Australia to Europe - is highly competitive, with around two dozen airlines offering flights. Qantas hopes that the new service will differentiate it from those other airlines, which all have to stop for refuelling in Asia or the Middle East.
According to Reuters, analysts estimate Qantas could charge a 20 per cent premium for tickets on the service in return for delivering business passengers to their destination more quickly.
The 17 hour flights from Perth will give Qantas a chance to test demand for ultra long-haul flights. It is also working on a research project with the University of Sydney to make long-haul flights less unpleasant. Research areas include strategies to counteract jetlag, on-board exercise and movement, menu design and service timing, pre and post-flight preparation, transit lounge wellness concepts and cabin environment including lighting and temperature.
The fact that Qantas is planning to spend several billion dollars on a new fleet demonstrates the success of the airline's remarkable turnaround engineered by Joyce.
As Joyce announced the plan to launch the marathon flights, he also released Qantas' latest annual profit. It is the airline's second highest profit in history, after last year's.
Underlying profit before tax for financial year 2017 was A$1.4 billion (NZ$1.5b), down 8.6 per cent from 2016, when it reported a record profit A$1.53 billion.
What is remarkable is that Qantas has achieved this result in the face of tough competition on its international routes.
Qantas said a flood of foreign airlines coming to Australia's shores had hurt earnings in its international business.
It is a far cry from where the airline was just three years ago, when it asked the government for financial assistance it said was crucial to its survival.
Qantas was refused help, but what Joyce's plea of 2014 underlined was the seriousness of the airline's plight, securing the support of unions for wage restraint and the patience of investors as the airline slid to a A$2.8 billion loss.
Joyce last week said the airline's three year turnaround campaign had been a success and had realised more than A$2.1 billion in benefits.
A strong domestic performance has driven Qantas' profits over the past year. In fact, Qantas and its budget offshoot Jetstar between them command 90 per cent of the profitability within Australia's domestic aviation market.
That is great news for Qantas and its shareholders, but not so much for the travelling public. Qantas is planning to cut its domestic capacity by 1 per cent next year in response to a reduction in demand from the mining sector.
It suggests the airline is not expecting much of a competitive threat from smaller rival Virgin and so will have more market power to increase prices on the slightly fewer flights it will offer.
At the same time, Qantas will increase overall capacity by 3 per cent, mostly by expanding routes and services into Asia. It is another sign of the airline's sure footing and its confidence in its future.
Over the past year, Qantas has paid down A$434 million in debt to reduce net debt to A$5.2 billion and it has A$1.8 billion in short-term liquidity available to it.
This means that when the next crisis hits global aviation, and that will almost certainly be sooner rather than later, be it from surging fuel prices, terrorism, an airborne disease or something we haven't seen before, Qantas will be in a strong position to withstand the storm.