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Reaction Engines To Fly Reusable Spaceplane
RobGoldsmith writes "Reaction Engines have designed a 'reusable spaceplane' to provide inexpensive and reliable access to space. The Star Wars-looking 'Skylon' reusable spaceplane has already been designed and the team are well into engine testing. They have taken some time out from building spaceships to talk about their background, their goals, and their recent engine tests. This article shows new images of their STERN Engine, an experimental rocket motor which explores the flow in Expansion Deflection (ED) nozzles. They also discuss their Sabre air-breathing engine technology. View the Skylon Spaceplane concept, the STERN Engine and much more in this in-depth interview with the team."
Reaction Engines is the name of the company. It's using conventional LOX/LH2 engines.
And for those who are calling this Shuttle 2.0, it's unmanned.
Fascism starts when the efficiency of the government becomes more important than the rights of the people.
You know, the day Sputnik went up hardly anyone was thinking about a commercial use for space, and now look at us. Space has definitely become a "build it and they will come" scenario. If you make payload lifting even cheaper, there will be more customers because things that didn't make sense before suddenly start to.
From http://www.reactionengines.co.uk/skylon_dev.html :
The total development program will cost about $10 billion.
Also... http://www.reactionengines.co.uk/skylon_vehicle.html
Skylon Statistics
Length: 82m
Fuselage Diameter: 6.25m
Wingspan: 25m
Unladen Mass: 41,000kg
Fuel Mass: 220,000kg
Maximum Payload Mass: 12,000kg
At the start of the take-off roll the vehicle weighs 275 tonnes, whilst maximum landing weight is 55 tonnes.
At take-off the vehicle carries approximately 66 tonnes of liquid hydrogen and approximately 150 tonnes of liquid oxygen for the ascent.
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Payload Capabilities
The Sklyon payload bay is 4.6m diameter and 12.3m long. It has been designed to be compatible with expendable launcher payloads but in addition to accept standard aero transport containers which are 8 foot square in cross section and 10, 20, 30 or 40 feet long.
It is anticipated that cargo containerisation will be an important step forward in space transport operations, enabling the "clean" payload bay to be dispensed with.
The vehicle can deliver 12 tonnes to a 300km equatorial orbit, 10.5 tonnes to a 460km equatorial spacestation or 9.5 tonnes to a 460km x 28.5 deg spacestation when operating from an equatorial site.
You do the per flight math.
Mit der Dummheit kämpfen Götter selbst vergebens
It doesn't seem to have enough propellant mass for the task. To get to LEO, it needs something like 7.5 km/s or more in delta v (ignoring very substantial gravity and air resistance losses). If it were purely a rocket, that would be roughly 7.2 km/s (rocket equation is delta v = -4420 m/s*log(53 tons/273 tons), where 4420 m/s is perfect exhaust velocity in vacuum for LOX/LH2 burning rockets). Even if we assume we can get to Mach 5 for free (which is 1.5 km/s roughly), that leaves no more than 1.2 km/s margin. A regular rocket picks up 1.5-2 km/s or so in gravity and air resistance losses. While gravity losses might be somewhat lower (due to lift), air resistance is definitely going to be higher than the 100-200 m/s a rocket of similar size would have. So we have gravity and air resistance losses. We also have probably an inefficient nozzle design with a tradeoff between greater bell size (and efficiency in vacuum) and lower air drag. Something like drop tanks would help a little, but there doesn't seem to be the space for a lot of extra mass there. Another possibility is to use denser fuel in place of LH2 for the early parts of the flight, but that weakens the isp a little.
I don't much like the idea of a space elevator, at least for short- or medium-term applications. (Long term, is 50 years from now, is different... but also not very relevant.) Why, you ask? Simple. Give me a space-elevator class building material, and I'll make rocket tankage out of it long before it's fully developed to space elevator performance levels. Those tanks will be so vastly superior in weight performance to current materials that I can give you a rocket that is not only single stage to orbit, but does it on *pressure fed* engines. Who needs turbopumps and all their associated machinery when you can just put enough pressure in the tanks (and run at a lower chamber pressure... which is more conducive to high reliability anyway)?
For a given payload rate, my pressure fed SSTO will use somewhere between 3 and 10 times the energy (depending on which kool-aid you drink when it comes to getting the power from the ground to the elevator car). It will have a *vastly* lower capital cost. It will be faster (no radiation worries for cargo that spends days passing through the van Allen belts). Perhaps more importantly, it will scale down better. It starts with a lower investment and lower flight rate to prove out demand, and then grows as more customers appear and more rockets get built.
Oh, reusability? It gets a lot easier when you don't have to jettison a stage a third of the way there -- and when your reentry vehicle is as light and fluffy as these building materials imply, it gets even easier. Engine reusability is pretty trivial when you don't have 60,000 rpm turbines wearing out all the time.
There are plenty of engineering problems to be overcome for a space elevator. They're not impossible, but they're far from trivial. But the real problem is the competition from rockets -- it makes zero sense to compare a space elevator built with magic nanotubes to a lithium-aluminum tankage rocket; it should be compared to a magic nanotube rocket. When you do that, you discover that for any unproven market (ie, where capital costs matter) the spaceship fleet is far, far cheaper.
Sounds like a Skynet-Cylon joint venture. Please don't be sinister-looking....
*Opens link*
Ah, crap.
Don't put advice in your sig.
from this presentation: ... ... ...
- air intake in the order of hundreds of kg per second (400 kg/s to quote)
- passes through thousands of small tubes (resistance at that speed ?!?)
- in a few milliseconds
- cooled from + 1000degreesC to -150degreesC
Forgive me my ignorance, but are these materials physically possible ?
"Violence is the last refuge of the competent, and, generally, the first refuge of the incompetent" - Thing_1
Look into the Space Fountain instead... http://en.wikipedia.org/wiki/Space_fountain
How many "2.0" Internet businesses exist only because of the unexpected consequences of humanity building the largest peer based computer network in existence?
Slashdot itself, and other newcomers like Netflix "on demand" only exist because of the Internet. Did we build the Internet so that we could stream "Superman" in real time, or argue politics with people from around the world?
No. but they all happened because we built the Internet!
So build it! Society will profit in ways we can't today imagine today any more than Bob Metcalfe imagined Slashdot when he co-invented Ethernet!
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Actually, if you want a mega-scale engineering project, my personal preference is for the launch loop.
Is that what pretentious Brits call Aluminum?
Then you may need to work on your reading :-)
The precooler tests were run separate to the thrust tests. The thrust tests were related to the ED nozzle work.
As for the reliability, well when I wrote the test plan for the ED nozzle test engine, I can assure you, that reliability was very much part of the plan.
As for you not seeing any prototype being tested, note the photograph of a rocket shaped object with hot flame coming out of it in the News section?
I'm sorry the photograph isn't any better, but none of us were prepared to step outside the bunker during the hot firings. I'm working on improving the photos taken during test runs.