Britain is advancing plans to test a hypersonic space plane designed to significantly reduce travel time between London and Sydney to approximately three hours. The project, led by the European Space Agency (ESA) with support from the UK Space Agency, involves the development of the Invictus aircraft, which aims to reach speeds of Mach 5—over 3,800 miles per hour, or five times the speed of sound.
The Invictus will operate by taking off horizontally like a conventional airplane before ascending to the edge of the atmosphere at around 80,000 feet. From this altitude, the vehicle could either deploy satellites or rapidly traverse long distances, potentially transforming cross-continental air travel. Initially, the test models will not carry passengers; however, successful trials could pave the way for future hypersonic commercial aircraft.
Two UK locations are competing to host the first test flight: Spaceport Cornwall in Newquay and Spaceport Machrihanish in Scotland. The latter, a former Royal Air Force base on the Kintyre Peninsula with historical ties to testing Concorde and the B-2 stealth bomber, offers less congested airspace and proximity to Glasgow Airport, just a 20-minute flight away. Gordon Stevenson, a director at Spaceport Machrihanish, highlighted the potential for the technology, noting, "You could be in Sydney, Australia in three hours. It depends on the speed at which it flies and the success of the technology, but it would be amazing wouldn’t it?”
The development timeline anticipates completing the design phase for Invictus within 2026. Smaller-scale engine and hydrogen system tests are slated for the following year, with propulsion trials planned for the late 2020s. Initial test flights, expected by 2034, will operate at sub-hypersonic speeds, progressing to full hypersonic trials around 2036.
James Cornish, space business development manager at Frazer-Nash—the prime contractor on the project—explained that while Invictus itself is not intended for passenger transport, the technology validated through its testing could enable significantly faster long-haul commercial flight in the future.
The initiative comes after the end of supersonic commercial flights with Concorde’s retirement in 2003. Concorde’s top speed allowed it to reach Sydney in approximately 17 hours, but operational challenges included multiple refueling stops. Achieving hypersonic flight presents even greater technical difficulties, mainly because engines risk melting due to the intense heat generated at such speeds. While military fighter jets use complex cooling systems, these tend to be bulky, expensive, and inefficient.
To address this, ESA has partnered with Oxfordshire-based Reaction Engines to develop a pre-cooled hydrogen/oxygen propulsion system. This technology rapidly chills superheated air entering the engine, enabling sustained high-speed flight without overheating.
If proven successful, Invictus could mark a significant step forward in aerospace technology, reducing global travel times dramatically and opening new possibilities for both commercial aviation and satellite deployment.