credit: Virgin Galactic / caption: could SpaceShipTwo use a liquid propulsion system?

Virgin Galactic’s SpaceShipTwo could be a single stage to suborbit vehicle using liquid chemical propulsion according to independent research carried out by a company that has been contracted by the European Space Agency for suborbital and hypersonic transport studies

UK company Gas Dynamics has concluded, after its own internal study, using all the publicly available material it could obtain about SS2, that the spacecraft does not need its carrier aircraft WhiteKnight Two if it is fitted with a liquid chemical propulsion systemGas Dynamics has worked for ESA studying suborbital flight because of the agency’s interest in using such vehicles for technology testing. The compay’s own website refers to “Vinci: A cryogenically fuelled suborbital concept for the European Space Agency”

Hyperbola is not aware of any link between this ESA Vinci suborbital project and Gas Dynamics own internal SS2 study

However the UK firm came to the conclusion that the volume within which SS2 carries its solid rocket motor and nitrous oxide supply could equally hold a liquid chemical propulsion system capable of providing enough thrust for long enough for a horizontal take-off and ascent to 50,000ft and above without the need for WK2

Hyperbola had spoken to Gas Dynamics at an aerospace sciences conference held in the northern English city of Manchester a week or two before the 60th International Astronautical Congress held in Daejeon, south Korea. It was then that this blog learnt of the company’s internal SS2 study and related ESA work

At the IAC last October Virgin Galactic president Will Whitehorn mentioned in passing during his presentation that in future SS2 could use liquid propulsion and Hyperbola sent a cryptic tweet at the time expecting to be able to follow that up with a blog post in the future

This blog was hoping to gain further details about Gas Dynamics’ ESA studies in the months since the Manchester conference and IAC but senior European Space Research and Technology Centre managements’ nervousness about the perception of suborbital projects meant an interview could not be arranged before now