Concorde, the flag-bearer of supersonic aircraft, retired more than a decade ago. Some thought that the era of supersonic traveling will end in grave. But, some scientists didn’t lose the motivation and are still working on bringing the concept of supersonic air travel back to reality.

U.K.-based Reaction Engines is developing technology for Synergetic Air-Breathing Rocket Engines (SABRE), which could one day allow aircraft to fly up to five times faster than the speed of sound — that’s Mach 5 or 3,836 miles per hour. At that speed, hypersonic flights between London and Australia could be over in just four-and-a-half hours.

After the retirement of the Concorde in 2003, supersonic commercial air travel came to an end. With an average speed just above Mach 2 (1,354 mph), the Concorde’s fastest Transatlantic trip between New York and London occurred in 1996, lasting just 2 hours 52 minutes and 59 seconds.

Its retirement was seen by many as a real loss even as there were serious problems with commercial supersonic air travel, primarily the noise. It was prohibited from flying at supersonic speeds over land to spare those down below from the loud sonic boom as it flew. Though a sonic boom seems like a single event, the boom itself is relative to the observer, the boom itself simply being the moment the compressed sound waves of the aircraft finally reaching the observer. Traveling over land, a supersonic aircraft is essentially raking the ground below with its sonic boom.
Boeing has gone further than many of its competitors by unveiling a design for a hypersonic aircraft that could potentially travel five times quicker.

But for those speeds to be possible, the futuristic engines need to process air flows with extremely high temperatures. Now Reaction Engines has revealed that its precooler component – designed to manage extreme heat – has successfully handled temperatures of 420 degrees Celsius, matching the conditions it would face when reaching Mach 3.3 speeds. At that speed, an aircraft would be traveling three times faster than the speed of sound and 50 percent faster than Concorde.

The test took place at Reaction Engines’ facility at the United States’ Colorado Air and Space Port. They were the first phase of an extensive trial program, which will eventually see the precooler exposed to temperatures hotter than 1,000 degrees Celsius – the conditions expected during Mach 5 hypersonic flight.

In space rocket mode, the engines are being designed to speed a craft up to Mach 25.

Over the last four years, Reaction Engines has secured more than £100 million ($130 million) in investment from backers including BAE Systems, Rolls-Royce, and Boeing’s venture capital arm. The firm has also received a £60 million ($78 million) funding commitment from the U.K. Government.

The commercial feasibility and the impact of supersonic traveling on human bodies is yet to be tested. The technology is on the right path and with each successful tests, the day of supersonic traveling would come nearer.