Qantas flight planners are working on the fine details of what is shaping up as the final frontier for the airline.
The Australian carrier is near a crucial stage of its long-planned Project Sunrise programme, aimed at introducing new non-stop routes from New York to Sydney and London to Australia with new aircraft as early as 2022.
First, it needs to find out how those flights will affect passengers and crew, so it will trial the routes with three flights over the next three months.
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There will be about a sixth the usual number of passengers and crew on board and those in the trial will become human guinea pigs, wearing monitoring equipment and subject to a number of tests.
The airline will use the delivery flights of its latest Boeing 787-9 Dreamliners for the ultra-long-range trials.
Captain Lisa Norman will be in command of one of the New York-Sydney flights, a point-to-point distance of just under 16,000km.
''I'm an aviation nerd from way back so I think this is really exciting,'' says Norman, who also heads the 787 programme for the airline.
While London to Sydney point-to-point is around 800km longer than the New York trip, it has been done before. Just over 30 years ago Qantas flew a new 747-400 using modified fuel and carrying just 23 people on the route, taking just over 20 hours.
The Dreamliner flight this year is likely to use 40 per cent less fuel than that historic Jumbo mission but it will be the JFK-Sydney flight that will break new ground.
Norman says years of weather data will determine the flight path of the 787-9, which has seats for 236 passengers but will have 40 passengers and crew on what is private flight.
Qantas is using the new cloud-based Constellation system, which will analyse millions of pieces of data and recommend flight tracks. The airline already flies between Australia and the western United States and cross-country from Los Angeles to New York.
Norman says the Airbus A380s used across the Pacific are like ''flying weather stations'', so the airline has a huge amount of information about the route.
''We've been running plans from a fuel perspective and wind perspective because historically we know the headwinds get a little bit stronger at that time of the year coming out of JFK into LAX and then over the Pacific they're light and variable,'' she says.
Getting closer to Australia, the aircraft hit jetstream headwinds.
''We're running different routes to see what is the most optimised ones for us. When you're going west, you have the jetstream and that can add an hour.''
The flight could ''stay high'' and take a track straight across the continent, passing between San Francisco and Los Angeles and then cut down over Hawaii.
Another route could head as far south as New Mexico.
Those on the trial flight, mainly Qantas staff, have been advised to pack light and there will be minimal catering, but they will be travelling in comfort, sprinkled among the plane's 42 business class seats.
Norman says this nose-heavy passenger load will affect the pitch of the plane and planners have to allow for this.
''With everyone sitting up the front, that creates a bit more fuel burn,'' says Norman, who has been with Qantas for 30 years.
The plane would be filled with fuel and all up it will have a takeoff weight of 235 tonnes, 19 tonnes short of its maximum takeoff weight.
Crew on the flight will be stationed in New York to acclimatise for about four days ahead of takeoff in the middle of next month, and during the flight they will be monitored by a range of equipment including wearable technology, possibly headsets, so long as they don't interfere with communications gear.
The airline is working with experts from Sydney University's Charles Perkins Center and Monash University who will be testing alertness and levels of melatonin, key to regulating the sleep-wake cycle — before, during, and after the flights.
There will also be tests of cognitive ability.
Norman says the aim is to optimise the rostering of pilots that was developed during a long history of long-haul flying.
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''We have a fatigue risk management programme that's been in place for a long time - this is a continuous learning system based on predictive and reactive data.''
The airline has been flying Dreamliners from Perth to London since last March and has been taking fatigue data from crew, as well as from the Sydney-Dallas flight which is nearly the same distance.
Some passengers have worn wearable devices on the Perth-London service. Among early results, it was found that one passenger had not moved from his business-class seat for the duration of the nearly 18-hour flight.
Norman says the new round of tests will build on previous monitoring.
''I see this as the next extension and going further. With the level of science behind it, we can go into [Project] Sunrise with confidence in the systems,'' she says.
She also pays tribute to the crew who blazed the trail from London to Sydney, and Qantas planners will be looking at the track they took.
''We are a long way from where they were. Our forefathers were the pioneers and we're just continuing that and taking it to the next level of research.''
Ready to make the big call
Qantas has yet to make a decision on whether it will go ahead with Project Sunrise - flights from London and New York to Australia's eastern cities.
The economics have to stack up for the airline, which will make a call late this year as it decides whether its next ultra-long-range planes will be A350s or the Boeing 777X, which has yet to fly and has been delayed. At one stage, Airbus was working on underfloor ''pods'' for its A350s that would have had exercise space or sleeping areas.
It is understood that these are not feasible because of the lack of headroom, but the airline is concentrating on providing spaces where passengers can socialise and stretch.
Boeing is working with Qantas as a result of the delays in the 777X programme.
Boeing revealed in June that the aircraft was facing challenges because of problems with GE9X engines.
The 777-8 aircraft were initially planned to commence service by 2022, following the first flight of the 777-9 variant late this year. However in June, Boeing pushed the first flight of the 777-9 back to next year because of issues with the GE9X engine.
A Boeing spokesman this week said the first two 777X flight test planes were now in pre-flight testing.
''Our teams continue to make good progress and are currently focused on integrated systems, propulsion and airplane-level tests. Overall the airplane is performing well as we work through our pre-flight testing regime,'' he said.
''As with any development programme, we are being thoughtful and deliberate, taking the time to get the details right with safety as our top priority. We will fly only when we are satisfied with the performance of the aircraft.''
For ultra-long-range flying, airlines not only have to get the right planes, but also the right onboard products.
For its Perth-London flights Qantas has a special menu and a bigger range of non-alcoholic drinks. The lighter food contains ingredients aimed at increasing hydration and the meal service encourages sleep at optimal times during the flight to reduce jet lag.
The airline designed a special lounge in Perth where there is "light therapy" in the 15 shower suites to help adjust the body clock, a wellbeing studio with stretching classes and a refresh area providing hydrating face products.
Singapore Airlines uses a specially configured A350-900ULR (ultra long range) aircraft for its flights between Singapore and New York (Newark), which is now the longest commercial flight in the world at 16,700km. It too has a special menu for the 161 passengers who are in business and premium economy seats.
There is no economy section.