The rocket in BLOODHOUND SSC is a hybrid design that uses high test peroxide (HTP) as its oxidiser. Around 800 litres of this HTP needs to be delivered into the rocket at 76 Bar (1000psi) in just 20 seconds, which is why the design of the pump is so vital.
A bit of history
The pump for BLOODHOUND was originally developed from the large HTP pump from the Stentor rocket engine that was used in the Blue Steel cruise missile, which was carried by the RAF’s V Bombers in the 1960s. The design was reverse engineered with the help of one of the original designers, John Scott-Scott, as engineering drawings were not available. In particular, the design of the volute – the casing that receives the fluid being pumped by the impeller – was improved to provide the increased performance required for BLOODHOUND.
The impeller was further developed in 2014, with the new design evolving from a smaller unit by the same designer, which was a competition-winning liquid oxygen pump. Mark Elvin, one of BLOODHOUND’s Engineering Leads, then adapted the design to work in the existing volute chamber. He took the lead from its design, but had to work within the realms of what was possible from a manufacturing perspective, as it had become a very challenging, single piece, 5-axis machining that was particularly difficult for Conor La Grue to find someone to make.
The impellor has three bladed axial inducers leading to three full-length impeller blades, partnered with three half-length impeller blades and a further 12 quarter-length blades – giving a total of 18 impeller blades of various lengths.
The final design of impeller is now incredibly efficient, and matches perfectly with the Jaguar 550hp V8 engine which is powering it.