Are supersonic passenger flights going to make a comeback?

London to Miami in five hours is promised for the next generation of high-speed passenger planes

Boom time: Artist’s impression of the Overture supersonic jet (Boom Supersonic)

The last passengers to experience a transatlantic crossing in barely three hours boarded British Airways BA2 from New York JFK early in the morning of 24 October 2003.

As the Concorde approached London later that day, it was joined by two other supersonic jets, which flew low over the capital before landing at Heathrow airport.

The Anglo-French aircraft was grounded by a combination of high oil prices, low demand and concerns about safety following the 2000 crash in Paris in which 113 people died.

The airline says: “British Airways withdrew Concorde, bringing to a close the world’s only supersonic passenger service.”

Since then various companies have worked on possible new-generation high-speed aircraft, but one is well ahead of the field: Boom Supersonic, based in Denver.

The Colorado company says its plane, known as Overture, will fly at Mach 1.7, which is one-sixth slower than Concorde but still twice the speed of conventional subsonic aircraft.

At a cruising altitude of 60,000 feet, Mach 1.7 equates to a ground speed of around 1,050mph – slower than Concorde, but around twice as fast as current short-haul aircraft, which fly at around Mach 0.85.

The range, says Boom, will be 4,888 miles (4,250 nautical miles). That is only about one-sixth more than Concorde’s maximum. But it would comfortably open up many more route options such as:

• London-Miami (4,425 miles)
• Los Angeles-Lima (4,167 miles)
• Seoul-Honolulu (4,577 miles)
• Brisbane-Tokyo (4,425 miles)

Boom Supersonic says potentially there are more than 600 “profitable routes” for the Overture.

Journeys from US east coast cities such as Boston, New York, Washington DC and Miami to London, Paris, Dublin, Lisbon and other European hubs are likely to comprise the key market.

Those routes would be mostly over water, which is where Overture would be able to fly at full speed; over land, the sonic boom created by breaking the sound barrier would be unacceptable.

Not only will Overture be slower than Concorde, it will also be smaller. The maximum passenger capacity will be 80, compared with 100 on the Anglo-French supersonic jet.

In the cabin, Boom promises “An Elevated Passenger Experience … that maximises value to our airlines and is beloved by their passengers.”

The company says that its order book “stands at 130 aircraft”, including both orders and pre-orders from major airlines such as United, American and Japan Airlines.

In 2017, the company said it would be flying scheduled services by 2023. The entry into service is currently set for 2029.

Rhys Jones of the frequent-flyer website headforpoints.com said there are huge technological and environmental hurdles to overcome: “Whilst I’d love to see the return of supersonic flight, I struggle to see how this will work with current engine technology.

“Unfortunately for supersonic travel, our awareness of environmental issues has changed hugely since Concorde took its last flight in 2003. Airlines are doing everything they can to use less fuel, with many committing to net zero by 2050.

“They will come in for huge criticism if supersonic aircraft such as Boom’s Overture are not as efficient per passenger-mile as existing aircraft.

“Boom says that the Overture will be net carbon neutral, but this is based on the use of sustainable aviation fuels. If the Overture requires twice as much of this fuel per passenger mile versus a subsonic aircraft then arguably the fuel would be better used on a conventional jet plane, where it could fly two people across the same distance rather than just the one.”

Boom Supersonic says the premium seat-mile cost of Overture will be lower than for subsonic aircraft. Accordingly, says the manufacturer, airlines will be able to operate profitably while charging normal business-class fares.

Concorde sold at a premium to British Airways first-class fares.