18-05-2025
Everything you need to know about taking an ‘ultra long haul' flight
By the end of 2026, it should be possible to fly direct from London to Sydney in around 20 hours aboard an A350-1000. Codenamed 'Project Sunrise', Qantas's plan to cut flight time between the two cities by up to four hours (compared with those that include a stopover) has been nine years in the making.
The airline has reportedly invested around $4.4 billion into 12 new planes to make this journey – alongside another route between New York and Sydney – as comfortable as possible, while an extra fuel tank means the aircraft can fly for up to 22 hours. But, though London-Sydney is scheduled to be the world's longest ultra long haul flight, it's far from the first.
Back in 1936, a Pan Am flight from San Francisco to Hawaii took more than 19 hours to reach its destination, despite flying less than 4,000 kilometres. It wasn't until 2004 that ultra long haul (ULH) flights as we know them took off, with Singapore Airlines's route between Newark and Singapore Changi clocking up more than 15,000 kilometres. Though very long flights briefly fell out of favour with rising fuel costs, the airline now operates what's currently the longest route in the world: JFK to Singapore Changi.
But what does taking an ULH flight mean for you, your body and your wallet? Find out below…
What is an ultra long-haul flight?
Officially, the term applies to any non-stop flight which is more than 16 hours in duration – of which there are currently around 30, though most originate or land in the United States. There are also flights from Doha to Auckland, Shenzhen to Mexico City and Paris Charles de Gaulle to Perth, while Qantas already operates a non-stop one between Heathrow and Perth, with a flight time of just under 17 hours.
As well as being easy and convenient for passengers, ULH routes have benefits for airlines, too. For example, they usually have more first and business class seats to cater for business travellers and leisure passengers willing to pay a higher price to ensure greater comfort. Even in economy, tickets are likely to be more expensive than journeys with multiple legs: the cheapest direct flights from London to Perth in October 2025 at the time of writing were £1,833; add a stopover in Singapore and the price drops to £1,139.
'ULH flights disproportionately attract premium travellers,' says the founder of aviation consultancy firm BAA & Partners, Linus Benjamin Bauer. 'With business class and premium economy yielding more per seat than economy, these routes can materially lift overall profitability.
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 seat pitches. But, while the cheapest seats will have 33-inch pitches, 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 London and Sydney. 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 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.
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 – but not from the UK in the near future. 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'.
