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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."
Can anyone find a cost per kg (or lb) of cargo estimate on that website? Not trying to detract from its value, just wanted it for comparative purposes.
I never thought that the Firefly form factor would ever actually fly, but look at the picture of the Skylon and tell me you don't see the resemblance!
Actually I see more of an SR-71 Blackbird with a fat tail. Can really see it here from above.
"You saved 1968." - Ms. Valerie Pringle to the crew of Apollo 8
Do not want shuttle 2.1. Do want Space Elevator. Now get to work.
Are you personally picking up the tab for this space elevator? Even an RLV doesn't have much of a business case to be made. There simply isn't that much demand. A space elevator needs a lot more demand than has been demonstrated to exist. A reasonable plan is to build up the demand to the point that exotic launch systems make business sense. Not develope the exotic launch system and hope someone will use it.
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.
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.
Sure, nobody wants to lift cargo at the current price point. Try cutting it by 90% and see what happens.
"We returned the General to El Salvador, or maybe Guatemala, it's difficult to tell from 10,000 feet"
Sounds like a Skynet-Cylon joint venture. Please don't be sinister-looking....
*Opens link*
Ah, crap.
Don't put advice in your sig.
Sure, but guess what? I bet even current launch vehicles can do a lot better in cost per kg than they currently do. I figure the limit of expendable launch vehicles are somewhere around $500 per kg in very high launch volume (thousands of launches a year). RLV would drive that to somewhere around $100 per kg. At that point, you have the business to justify that next step to exotic technologies like space elevators, rail launch, etc. This is the point that I think is being missed. There's little reason to fund a lot of space elevator research now. And by the time there is enough reason, it pays for itself.
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
Hmmm ... I would suggest GL to sue that company for (R) infringement!
And later (from a galaxy far far away) the Empire will sue GL!
Maybe Computers will never be as intelligent as Humans.
For sure they won't ever become so stupid. [VR-1988]
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.
From what I saw at the company website, it looks like they're building the orbital equivalent of the first commercial airliner, the DC-3.
If they can get the cost to orbit even remotely close to the $200/kg number the Space Power Satellite program proposed by NASA was based on, we could either build a full system or a large proof of concept orbital power array. We're a bit more desperate for power than we were when Bush defunded the SPS project. The launch capability is the hard part of SPS, the rest is just engineering we know how to do.
That could take up enough launches to provide the company a reasonable chance at profit.
Tech Public Policy stuff
Hmm... as I'm getting old I thought I remember this concept as HOTOL, and sure enough: wikipedia Reaction engines was started by one of the HOTOL designers. Still, it's had probably 30 years of intellectual development and it looks believable to me. Go Reaction Engines.
-- For evil to triumph it is enough that good men do nothing.
Actually, if you want a mega-scale engineering project, my personal preference is for the launch loop.
It's what the Yanks call an Aluminium Falcon.
I'm guessing that wasn't on their radar screen...
Is that what pretentious Brits call Aluminum?
And what pray tell does that have to do exactly with what the OP said, of "if you build it they will come"? No one said this stuff had to come immediately. The space shuttle is the first re-usable spacecraft the US created. Many of the first escort fighters (Allison-engined P-51 mustangs didn't live up to expectations either, nor did the first assault rifle for the US (M-16 before they lined the barrel and chamber with chrome).
First and early attempts rarely tend to their tasks as well as people hope or require. Typically you have to go through several revisions while the old models are still "in the field" as it were. Really the only difference is the expense of space exploration. NASA has been able to do some slick stuff on a low budget since the 60's or 70's, but its been a hamper.
You mention no one has gone back to the moon in the last few decades. What, may I ask, exactly would you have them do there? They still have the moon rocks from Apollo. We've gotten pretty handy with a spectrometer, being able to tell chemical compositions of planets and stars light-years away. What exactly were they to do there besides build a telescope, which we have easily done in orbit anyways (see Hubble).
The economics of space exploration are slowly changing to make it as feasible as deep ocean exploration (which is also hurting from lack of interest, outside of oil companies). The politics of it are leading to like what? Three manned missions from countries outside the US? I believe Russian, India, and China were all discussing targeting the southern end of Luna.
Anyways, manned space exploration will continue to happen and eventually we will colonize other planets. The pace of space is different. The amount of resources it takes to leave Earth and head for another system are unlike anything we've had to deal with before. The distances likewise, with it easier to measure it light-seconds and light-minutes or AU within the solar system than kilometers.
How long has it taken humanity as a whole to explore the bulk of the dry surface of Earth? You do realize I hope that there are large uncharted tracts of land. This is why we still discover new species as we cut down the rain forests. And don't even get me started on the sea, we don't even know what all is living in our oceans and can't even reach the bottom in some places.
Personally I say do as much as we can from remote without sending people out as possible. Saves lives, saves money, saves time. Voyager 1 and Voyager 2 are still sending information back occasionally. They haven't left the solar system entirely yet. In the last 10-15 years we've uncovered more information about our solar system than in the previous hundred. We're learning more about all the planets every day, and we haven't been sending out people.
May as well find out what we can know before sending someone out since we may not have too many shots to do so.
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.
Can I trust my payload and/or investment dollars to a company that uses "whilst" on their site?
The Brits and everybody else on the planet. ;)