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Spaceplane Concept Receives Euro Funding
draevil writes "BBC News reports that the novel "Skylon" spaceplane design of British firm Reaction Engines has received funding to proceed with its proof-of-concept design for an air-breathing rocket engine.
If successful, the Sabre rocket engine will be able to take the Skylon with 12 tonnes of cargo from a runway, to orbit and then back to that runway without the need for disposable components or a piggy-back ride on a larger aircraft.
Should the design prove viable, it could see first use within ten years."
..That someone built a spaceplane. Too bad the US is busy cutting NASA budgets to fund a new welfare program.
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
While the chances of this thing actually working is very slim, it is a very smart move to fund this sort of thing. At a million euros a pop, you can afford to fund a awful lot of projects that goes no where in order to find the diamond in the rough.
>"...the Sabre rocket engine will be able to take the Skylon with 12 tonnes of cargo..."
That should read "two Sabre rocket engines will be able to take a Skylon with 12 tonnes of cargo..."
That is 13.225 US Short Tons...or approximately 6 tons per engine, if the illustration is any indication.
Space Craft Blog feeds
Give the money to Noble. He'll use it to train the next generation of advanced engineers on a fun project that will actually go somewhere. Looking at the history to date of US efforts to develop scramjets (and this thing is basically an extended scramjet and therefore even more complex and expensive) a million Euros won't even pay for the project manager's office.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
It does work on the ground. It is not a scramjet. It is a hybrid between a jet engine and a rocket engine. It uses a jet style rotary compressor. The big innovation appears to be very fine control of the liquid hydrogen injectors into the combustion chamber allowing pressurised but gaseous air to be used instead of the liquefied air/oxygen that all previous rocket designs have needed.
Since it will accelerate all the way to orbit there shouldn't be a problem getting fuel out of the tanks. For burns in orbit a hydrazine based reaction control system should be sufficient.
Liquid oxygen is as compact as oxygen can be made. For fuel, kerosene is more compact than hydrogen.
I don't see an issue with guidance. An iPhone will do a pretty good job of it in this day and age.
BTW I don't think this space plane thing will work but I do think the engines would be great for a high speed military vehicle. Something to get a payload to the target really fast. It could do unpowered semi ballistic lobs as well.
http://michaelsmith.id.au
a few hundred kilos of oxidiser
The oxidiser weighs a lot. Take the shuttle for instance, at take-off the shuttle proper weighs 109,000 kg, the external LOX tank? 629,340 kg (just the LOX, not the LH2).
On the ground they won't be moving fast enough to scoop oxygen out of the air
"The Sabre engine is essentially a closed cycle rocket engine with an additional precooled turbo-compressor to provide a high pressure air supply to the combustion chamber. This allows operation from zero forward speed on the runway and up to Mach 5.5 in air breathing mode during ascent."
The engine is air breathing up to mach 5.5, it can do this because of a) it's novel pre-cooler design, and b) because unlike other air breathing designs, it doesn't liquefy the oxygen before using it as fuel, it 'merely' takes it to it's vapour point.
After mach 5.5 it operates as a relatively standard rocket engine up to orbital velocity (~mach 25) but by that point it's high enough that it doesn't have to fight through the thick air near the earth's surface so saves a lot of fuel. This increases the percentage of launch weight that can be used for payload.
You're wrong about the engines, the engines are actively cooled at the inlet- they see ground level conditions throughout the flight.
You're also wrong about nitrogen, nitrogen is perfectly good reaction mass up to about Mach 5. Beyond that it tends to come apart. Guess what speed Skylon calls it quits and turns on the rockets?
The other point you're missing is that at low speeds rockets are horribly inefficient; the exhaust velocity is much too high. By using the nitrogen as reaction mass; powered by the hydrogen fuel reacting with atmospheric oxygen Skylon can reduce the exhaust velocity and get massively better efficiency. That means it needs a lot less propellant, and then when it does turn on the rockets, it has performance in hand. The design has twice the payload fraction of a rocket design because of that.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"