Friday, February 20, 2009

Achieving orbit in style

Skylon Rocket/Jet Hybrid Is, Scientifically Speaking, Super Cool

The Skylon reusable space plane takes off from an airport runway, burns atmospheric oxygen, switching to liquid oxygen and hydrogen to hit escape velocity and attain orbit. At least, it will in 10 years.

The plane will be designed to carry 12 tons of payload into orbit and return safely, without having wasted $100 million worth of throwaway rocket. The company behind this hybrid shuttle is Reaction Engines, which just got a million euros in funding to prove that its "air breathing" Sabre engine can work.

1 comment:

Amateur Rocket Scientist said...

Very cool looking, apparently unmanned, transorbital prototype vehicle. The jet engines on the wingtips are very reminiscent of the Blackbird SR-71 turbo/ramjets, with their movable inlet spikes.

An excerpt from the BBC article, which notes:

"The Skylon concept's key enabling technology is its Sabre propulsion system.

"It is part jet engine, part rocket engine. It burns hydrogen and oxygen to provide thrust - but in the lower atmosphere this oxygen is taken from the atmosphere.

"At high speeds, this requires Sabre cope with 1,000 degree gasses entering its intake. These need to be cooled prior to being compressed and burnt with the hydrogen.

"Reaction Engines' breakthrough is a remarkable heat exchanger pre-cooler.

"Arrays of extremely fine piping plunge the hot intake gases to minus 130C in just 1/100th of a second."

That seems extraordinary--atmospheric gasses at 1000C (from air compression at high speed when entering the upper atmosphere or deorbiting?) having to be cooled to minus 130C in just 1/100 of a second?

That seems an almost ridiculously quick temperature phase change--somehow I doubt even a non-standard heat exchanger with micro-capillary arrays could do that so quickly--some kind of onboard cryogenic technology would be required to assist. Very weird.

Interestingly, there is some witness evidence or rumor than a similar single stage (or more likely two-stage) to orbit vehicle prototype has already been tested out of Area 51 (two-stage meaning similar to an XB-70 size "mothership" launching a smaller orbital craft, like the few old autonomous D-21 spy drones launched initially from SR-71's) almost 10 years ago.