A US company’s prototype jet has broken the sound barrier in a demonstration it hopes will pave the way for a successor to the Concorde.

Boom Supersonic’s XB-1 is the first civilian aircraft to achieve the feat since the British-French supersonic airliner, which was retired in 2003.

The XB-1 broke the sound barrier for the first time over the Mojave Desert in California.

During the test flight, it reached an altitude of 35,000ft before accelerating to Mach 1.1 (844mph) – 10% faster than the speed of sound.

The jet, which was flown by Boom Supersonic’s chief test pilot Tristan “Geppetto” Brandenburg, went on to reach Mach 1.1 two more times.

A live stream showed the test flight as it happened.

Denver-based Boom Supersonic hopes the XB-1 will pave the way for the development of Overture, the company’s supersonic commercial airliner.

The XB-1 is around 63ft-long, around one-third the size of Overture, which is intended to seat between 64 and 80 passengers and travel at speeds of up to Mach 1.7.

Such speeds would be around twice as fast as subsonic passenger jets, but still slightly slower than the Concorde.

The Overture has already been pre-ordered 130 times by companies such as American Airlines, United Airlines, and Japan Airlines.

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What happened to Concorde?

Concorde was a British-French supersonic airliner which predominantly flew routes between New York and London or Paris.

It could accelerate up to around Mach 2 (1,354mph) – more than twice the speed of sound – and carried around 100 passengers.

In July 2000 an Air France Concorde crashed shortly after take-off, killing all 109 on board and four people on the ground. It also led to the fleet being grounded for a year.

Maintenance issues, high operational costs and the impact of the 9/11 attacks on air travel led British Airways and Air France to retire the Concorde in 2003.

Donald Trump thinks the Chinese startup DeepSeek, which claims it has a technical advantage over US rivals, should be “a wakeup call” for American AI firms.

DeepSeek says its artificial intelligence models are comparable with those from US giants, like OpenAI which is behind ChatGPT and Google’s Gemini, but potentially a fraction of the cost.

That has triggered a fall in various US shares, especially chipmaker Nvidia which registered a record one-day loss for any company on Wall Street.

But the US president believes the success of the Chinese firm could be helpful to America’s AI aspirations.

“The release of DeepSeek, AI from a Chinese company should be a wakeup call for our industries that we need to be laser-focused on competing to win,” Mr Trump said in Florida.

He pointed to DeepSeek’s ability to use fewer computing resources. “I view that as a positive, as an asset… you won’t be spending as much, and you’ll get the same result, hopefully,” he added.

On Monday, the DeepSeek assistant had surpassed ChatGPT in downloads from Apple’s app store.

OpenAI CEO Sam Altman has given his rival some acknowledgement in a post on X, reacting to DeepSeek’s R1 “reasoning” model – a core part of the AI technology which answers questions.

“DeepSeek’s r1 is an impressive model, particularly around what they’re able to deliver for the price,” he wrote.

But Mr Altman was also defiant: “We will obviously deliver much better models and also it’s legit invigorating to have a new competitor! we will pull up some releases.”

There have been concerns DeepSeek could undermine the potentially $500bn (£401bn) AI investment by OpenAI, Oracle and SoftBank in Stargate which Mr Trump announced last week at the White House.

That project essentially aims to build vastly more computing power to boost AI development.

But while addressing Republicans in Miami on Monday, Mr Trump remained upbeat. He claimed that Chinese leaders had told him the US had the most brilliant scientists in the world.

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He indicated that if Chinese industry could come up with cheaper AI technology, US companies would follow.

“We always have the ideas. We’re always first. So I would say that’s a positive that could be very much a positive development.

“So instead of spending billions and billions, you’ll spend less, and you’ll come up with, hopefully, the same solution,” Mr Trump said.

The intense attention on the Chinese firm has not all been good news though. It reported suffering “large-scale malicious attacks” on its services.

The company said it was hit by a cyber attack on Monday which disrupted users’ ability to register on the site.

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As thousands of Palestinians head back to their homes in Northern Gaza, US correspondents Mark Stone and James Matthews find out if Arab Americans who backed Trump in November are still happy with their choice, or if his comments about ‘cleaning out’ the Gaza Strip have rocked their confidence in the President.

And, diplomacy via social media? What does Donald Trump’s almost-trade war with Columbia, and the way it was resolved, tell us about how the Trump administration will handle international affairs?

You can email James, Martha and Mark on trump100@sky.uk