A SUPERSONIC jet vying to bring back Concorde speed trips across the globe has reached an important new record - but it could be a bit longer until passengers get to fly on it.
US firm Boom Technology has been testing the "Son of Concorde" supersonic aircraft, officially known as XB-1.
It could eventually cut journey times from London to New York City to just 3.5 hours, down from the eight or so hours it currently takes.
The company has been progressing with test flights toward Mach 1, the speed of sound.
In its ninth test flight, a new maximum speed of Mach 0.87 - the equivalent to 667mph - was reached.
And the XB-1 also achieved a new record height too, climbing 27,716 ft.
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"Flight nine focused on clearing flutter points at increased speeds and varying altitudes to ensure the aircraft structure continues to behave as predicted in the expanded flight envelope," Boom Technology said in an update.
"This type of testing measures the interaction of the aircraft structure with the atmosphere it is flying through and is critical as XB-1 continues to reach higher speeds."
Engineers made changes to the flutter excitation system (FES) which is an important part to avoid structural failure.
Boom had been hoping to carry out its first supersonic flight later this year.
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But due to the essential modifications to keep the flights safe it will now take place in early 2025.
Before then, one more test flight is expected to take place.
Although no launch plans or date to carry passengers have been announced just yet, the pushing back of test flights will surely mean any such fully-fledged commercial passenger service faces a delay.
Boom Technology says it has also continued a series of tests in collaboration with the Defense Innovation Unit (DIU) and Air Force Operational Energy Office.
Before flight eight, a shark skin-inspired ‘riblet’ package was added to XB-1’s aft underbelly for durability testing at transonic and supersonic speeds.
This new material aims to reduce drag, fuel consumption and emissions, especially at high speeds.
The company has also revealed new footage taken from its seventh flight, which took place in early November.
In it, we get to see stunning views over Mojave Desert, California, where chief test pilot Tristan “Geppetto” Brandenburg has been flying the jet over the last year, as well as a look behind the cockpit.
Speaking to The Sun exclusively earlier this year, Geppetto said the jet will be much cheaper than the Concorde, which he says failed because of its fares.
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"Part of the reason the Concorde isn't flying anymore is just because it wasn't a sustainable business model," he explained.
"The flights were so expensive that the average person just couldn't afford to take those."
Remembering Concorde
THE CONCORDE was the first supersonic passenger-carrying luxury airplane.
Two decades ago the Concorde took its first-ever flight.
It became supersonic in 1969, flying passengers from New York to London in less than three hours.
It was the only aircraft in the British Airways fleet that required a flight engineer.
Concorde needed unsustainable amounts of fuel and created very loud sonic booms.
Then, in July 2000, a horror accident saw 113 people killed when an Air France Concorde ran over a small piece of metal while taking off from Charles de Gaulle Airport.
It caused the tyre to explode and the engine to ignite.
A year after the horrific crash, 9/11 majorly affected passenger numbers.
Ultimately a combination of these events led to its downfall.
By 2003, Air France and British Airways announced they would be retiring their fleet of Concorde planes.