System study results for SABRE-powered reusable launcher
An ESA-funded study has highlighted the challenges and benefits of launch services based on reusable hypersonic spacecraft to complement Europe’s launch capabilities beyond 2030. The proposed system uses a hybrid air-breathing rocket engine called SABRE.
The Synergetic Air-Breathing Rocket Engine, SABRE, is being developed by Reaction Engines in the UK and has previously been supported by ESA. This engine could be used to power a horizontally launched vehicle using either a one- or two-stage-to-orbit concept. In both cases, the SABRE-powered first stage would be fully reusable.
During flight, SABRE is designed to reach hypersonic speed through Earth’s atmosphere before switching to rocket mode on the climb to orbit.
In air-breathing mode, the engine utilises ambient air to burn on-board fuel allowing it to reach speeds up to Mach 5.
At an altitude of about 25 km, SABRE would then switch to rocket mode turning to an onboard source of oxidiser and fuel with which to continue its ascent.
In a two-stage launch system the upper stage carrying the payload would be released at an altitude of about 150 km to continue its path to orbit while the first stage would return to land on Earth for reuse.
Reaction Engines conducted this study supported by ArianeGroup and Bryce Space & Technology. ArianeGroup provided guidance on cryogenic technologies and proposed concepts of an upper stage for exo-atmospheric flight phases. Bryce Space & Technology provided market perspective beyond 2030 and supported business analysis for the launch service.
The study converged on a two-stage-to-orbit launch vehicle targeting specific payload classes for insertion into low Earth orbits from Europe’s Spaceport in French Guiana.
“The results of this study highlight the technical and economic challenges of a reusable launch vehicle based on existing SABRE technology. It encompassed the space and ground segment right up to maiden flight,” explained Jamila Mansouri, Space Transportation beyond LEO Manager at ESA.
Oliver Nailard, Business Development and Strategy Executive at Reaction Engines commented, “We’re seeing an incredible pace of development and change within the space industry. It is important we understand how SABRE propulsion can be deployed in order to optimise the operational, performance and economic benefits of the concept. This was a great opportunity to work with ESA and international expertise on that challenge.”
This study was carried out within the Future Launchers Preparatory Programme of ESA’s Space Transportation directorate and is intended to frame further activity within a 2022–2025 horizon.
