Will 20-hour flights be bad for you? What to know about ultra-long hauls

Sydney Morning Herald

03-06-2025

The production and implementation cost of a premium economy seat is 1.6 times higher than that of an economy class seat, yet it generates 2.3 times higher revenues than its production cost.' Qantas may also be hoping that its new route will cut competition from Middle Eastern and Asian carriers with well-used stopover hubs. ​​
How do you pass the time?
Love movie marathons? You're in luck. On Qantas's new route, you could potentially watch as many as 13 feature-length films – and you won't even need to pack snacks (these will be available in self-service fridges onboard).
Served meals, however, can feel few and far between when flying ultra long-haul. On Singapore Airlines' 19-hour JFK-Singapore route, there's (tray) table service for only dinner and breakfast, with light snacks in between.
The good news is there's a lot more than 'chicken or beef' to eat on these flights. 'Meal services are being re-engineered,' says Bauer. 'For example, lighter, low-inflammatory meals with adjusted timings help modulate melatonin levels and align with passengers' destination time zones – a practice pioneered by Qantas and Singapore Airlines.'
What's it like to sleep on board?
First and business class passengers should have no problem getting some rest. Bauer says airlines are engaged in an 'arms race in premium comfort' and cites Qatar's business class QSuite, which comes with doors, mood-lighting and fully lie-flat beds, as the cream of the crop.
On Qantas's new planes, specially designed first class cabins are like small, but very sleek, bedrooms, complete with dining areas for two and comfy beds with flexible backrests. Business class passengers will sleep in lie-flat beds, and premium economy passengers get footrests and 40-inch (102-centimetre) seat pitches. But, while the cheapest seats will have 33-inch (84 centimetres) pitches (more than other Qantas planes), shelves for iPads and free Wi-Fi to help the time pass more quickly, spending 19 hours in economy still doesn't look like a particularly enticing prospect.
There may be another issue with shut-eye too. According to the Sleep Foundation, 'the circadian clock takes about 1-1.5 days to adapt per time zone crossed,' so it could take more than nine days to recover from an ULH flight between Sydney and London. A stopover in the Middle East means a more gentle adjustment and gives passengers the opportunity to seek out daylight and fresh air en route, both of which can help with jetlag.
Are ultra long-haul flights bad for your health?
Operators are keen to do whatever they can to make ULH flights as comfortable as possible. 'It's not just an amenity issue – it's a strategic imperative to justify premium pricing and mitigate health and fatigue risks,' he says. 'Some carriers are piloting AI-driven in-flight wellness apps that adjust lighting, and offer hydration reminders and stretch routines based on biometric feedback.'
Qantas's new planes will even have 'Wellbeing Zones' available to all passengers, featuring stocked fridges and 'movement areas' with guided exercises. Lights have been designed to 'optimise the circadian effects of different times' across all the cabins.
With so much being done to mitigate the ill effects of ULH travel, it may be tempting to skip the ankle and neck rolls and regular jaunts through the cabin that physiotherapists so often advise. Don't.
Flights lasting longer than 10 hours pose the greatest risk of DVT according to the American Society of Hematology. Meanwhile, easy exercises such as the ones recommended by physiotherapist Helen Davison in this article should help keep aches and pains at bay.
What can passengers do pre- and post-flight to mitigate any ill effects?
Embrace drink – just not the alcoholic or caffeinated kind. Experts suggest people can lose up to two litres of water on long-haul flights. Liquids can help keep headaches and joint swelling at bay and electrolyte sachets could help too.
Meanwhile, the UK Civil Aviation Authority advises moving bed and waking times in the weeks before flying, in order to more easily adjust to a new time zone. Passengers can also use an online jet lag calculator to find out the best times to seek out sunlight on arrival.
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There's no better excuse for a spa treatment either. At the Sofitel London Heathrow, guests can book an hour-long Jet Lag Recovery massage that starts with work on the legs and feet (and may help with puffy, achy ankles), before moving on to a tension-relieving back and shoulder massage and rehydrating facial.
Will we see more ULH routes?
Definitely. According to Bauer, 'Singapore Airlines and Qantas are exploring new non-stop services to secondary North American cities such as Boston, Chicago and Miami,' while 'Air India, under its Tata-led transformation, is evaluating a direct Delhi–Los Angeles route'.