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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."
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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.
We have a space plane [wikipedia.org].
No, we have a "Space Shuttle" that is launched vertically from a standard-type large rocket launch facility with a monstrously-huge and expensive to build and operate hybrid solid and liquid rocket launch vehicle.
A hybrid spaceplane using both air-breathing and pure rocket propulsion able to take off and land on a runway like an airplane with no Shuttle-type booster rocket system required is a whole other animal.
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
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.
Here here. They don't even blink an eye about handing the bankers billions of dollars. But they can't agree on any spending that would actually benifit our country. OK, its arguable as to whether space exploration is prudent right now. But the Republicans in congress are saying that expanding and repairing our worn out infrastructure is a total waste of money. No, they insist that if we just hand it out to the people who still have money, then magically, it will somehow help those of us who don't. What they are actually doing is called looting. They realize that they have driven us to the verge of collapse, and now they are just trying to horde as much as they can so they can come through the depression ahead of everyone else. They're getting kind of desperate right now because they are realizing that their $5 billion will only be worth $500 million in a few years.
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!"