The concept under investigation is Skylon, a vehicle proposed by the UK firm Reaction Engines Ltd (REL). Skylon would be powered by an air-breathing rocket engine that could enable it to take off and land at a standard runway.
Esa is providing £1m for the study, to be completed by the end of the year. It will look at how a Skylon vehicle might operate in a market for satellite launches from the early 2020s onwards.
The research will be led by REL themselves. It will address the economics and some of the outstanding technical issues. The latter includes examining the type of spaceport needed by the vehicle; and the team will visit French Guiana to see how a Skylon could fly out of Europe’s existing launch facility in the territory.
There will be work done also to define more clearly the upper-stage carrier required for the Skylon concept. As envisaged, the plane would fly to just above 300km and then release a secondary propulsion module to place a satellite in its final orbit. For telecommunications spacecraft, this would be at an altitude of 36,000km. It is an approach that was adopted by the US space shuttle in its early years.
Thales Alenia Space (TAS) of Italy will look at the specifications of this carrier. The desire is to make it recoverable, so that after deploying the satellite, the propulsion module would return to Skylon to be brought back down to Earth for use on a later mission.
The contract for the Skylon-based European Launch Service Operator (Selso) study has been issued by Esa’s launcher directorate. As well as overseeing work on the agency’s existing rockets, such as Ariane and Vega, the department keeps an eye also on future launch technologies.