'No escape': what will it really be like on board the first nonstop flights to London?

Will your city be the first to offer nonstop flights to London?

Sorry, Melbourne, Sydney just won the ultimate aviation race, with Qantas officially crowning Sydney as the launchpad for its historic, nonstop marathon flight to the UK.

Kicking off in October 2027 between Sydney and London, the ultra-long-haul route will shrink the historic five-day "Kangaroo Route" down to a single, 22-hour leap.

Named for the airline's double sunrise endurance flights during World War Two, the services will run on modified Airbus long-haul jets.

But while the aviation world is buzzing, a massive question mark hangs over the back of the plane: will everyday passengers actually endure nearly a day in economy?

Complex Travel Group managing director, Mark Trim, said only time will tell whether travellers will choose these flights over traditional routes.

While premium cabin demand is expected to be strong and command "very high prices for the few hours of transit time saved", it remains to be seen how economy passengers will react to "such a significantly long nonstop flight".

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Trim said on other ultra-long-haul services, including Singapore Airlines' A350ULR from Singapore to New York - which is a few hours less than Qantas's Sydney to London flight - the economy cabin has been removed entirely, and the offering is mainly business class with some premium economy seating at the rear.

"Based on the heavy contingent of corporate and luxury customers loyal to the Qantas frequent flyer program, it seems there would have been a demand for a 'premium cabin only' configuration, and arguably that would have maximised yield on this route," Trim told Explore.

"Perhaps Qantas was concerned about the optics and potential public backlash of excluding economy travellers."

He said by including economy and therefore restricting premium seats, Qantas will be able to "hold a high line on pricing, as they've been successful in doing on the Perth-Europe routes despite a now-outdated seat product on current 787-9 Dreamliners."

Another drawback is the timing of the launch, which has been delayed a number of times.

Trim says it will miss the key European summer travel window between April and September.

He also says, because of IATA global flight timetabling changing from the Northern summer to winter schedules, most new services will launch in the last few days of October, "so don't expect to take this flight in school holidays next year".

Airline Ratings CEO, Sharon Petersen, said the appeal is "enormous" for premium travellers.

"You board once, settle in and arrive having saved four hours," Petersen told Explore.

"Qantas, in our view, offer the world's best premium economy product and rank among the world's best long-haul airlines."

She said that makes the proposition "genuinely compelling", particularly for passengers wanting a good rest, uninterrupted.

But it's a different story in economy.

Qantas says the new nonstop flights will cut up to four hours off the travel time compared to current one-stop services.

The serviced will run alongside Qantas's existing Perth-London and Sydney-Singapore-London services.

The first Project Sunrise Sydney to London services will go on sale in February 2027.

Project Sunrise will fly in the A350-1000ULR aircraft, specifically manufactured by Airbus for Qantas, and fitted with an additional 20,000-litre fuel tank, enabling the aircraft to fly more than 16,000 kilometres, for up to 22 hours nonstop.

Qantas has purchased 12 of the aircraft in total, each configured with 238 seats across four cabins. The first aircraft has been delivered.