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SpaceShipThree to be Orbital Spacecraft
FleaPlus writes "The president of spaceflight company Virgin Galactic has recently
stated that if the upcoming suborbital service with SpaceShipTwo
is successful, the follow-up SpaceShipThree will be an orbital craft.
Although orbital spaceflights would be much longer and could
potentially dock with orbital
space stations, they are also considerably more difficult than
suborbital spaceflights. Other private firms working on orbital
spaceflight (and potentially in the running for Robert Bigelow's $50
million America's Space Prize for orbital flight) include t/Space
and SpaceX."
$100.000 for flying from LA to Sydney in approx 4 hours?
My wife's sketchblog Blob[p]: Gastrono-me
There's a very interesting writeup about the potential problems related to trying to reach orbit in these "scaled composites" "spaceships" at http://www.daughtersoftiresias.org/misc/ss1.html.
Basically, the biggest problem is that due to the simplicity of the engine design (the are examples of space shuttle engine and the SS1 engine on the page above), the design would never scale enough to reach velocities needed to get into orbit.
Before discussion about SpaceShipThree occurs, perhaps we should wait until SpaceShipTwo is actually constructed and tested
Why would anyone pay for a suborbital flight when they expect the next version to be orbital? There will be a few no doubt who think its worthwhile to spend a hundred grand on an e-ticket to nowhere, but probably not enough to cover costs.
Seems to me the whole idea of suborbital flight as a stepping stone to bigger things is a bad one. Its like expecting DOS to scale up to a multi-threaded multi-user graphical operating system. Maybe it can be done, but is the final product safe to use? Starting with technology designed from the ground up to do the mission makes a lot more sense to me.
I wonder what the re-entry strategy will be for an orbital version. Somehow, I can't imagine Rutan going with thermal tiles.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
I suspect that the engineers involved in Vigin Galactic are not complete morons, and might possibly know a little bit about high altitude flight and rocket engines. Perhaps even more than you do, surprising as that may seem.
If they set about designing an orbital craft, I'd hazard a guess and say that they wouldn't use an engine design that is known not to work. Likely as not, they'd use a different engine design that is known to work.
And assuming that they start on the ground. The lift they get by the "white knight" is a very big saver on fuel and engine weight since they do not have to go through the first layers of the atmosphere.
My wife's sketchblog Blob[p]: Gastrono-me
My thoughts as well ...
http://www.2r2s.com/irdt_concept.html
My wife's sketchblog Blob[p]: Gastrono-me
Sorry, but the headline says "SpaceShipThree", not "SpaceShipOne".
Just possibly it will have a differently designed engine?
Quite. What the hell is this rubbish? And why are they posting it as FP on every single thread? I have mod points today and I'm going to use them!!
Funny, that's what they said about SpaceShip One, it wasnt possible.
And frankly, he's out there advancing the cause of spaceflight while your just a lonely virgin in your mum's basement. Guess who I'm going to listen to.
"There's absolutely no way that White Knight / Spaceship One will scale up to an orbital vehicle."
Sigh. Where did they say it would use the same design as the current vehicles? Ah, they didn't.
"If Rutan thinks he can build a vehicle capable of travelling ten times faster than SS1 with high enough SI and all the rest of that engineering detail, great, let him try"
Putting people into space is 1960s technology: anyone with a few brain cells and enough money can do it. The only question is whether Rutan can do it cheaply enough to make space tourism viable.
It is modded out already (as far as possible with the moderation system), the bad part is, that this person who posts that message has now posted it several times, thus making you, me and others look at that nonsense and most likely hurtfull text several times now.
/. visitor and contributor (ok, all my contributions are denied sofar), ask /. to CENSOR /. for certain messages, and block access for certain IP addresses which post offtopic texts with highly likely hurtfull content.
Search engines will also pick it up, that way spreading it even further.
A change in the moderation system would be nice, but writing this down will probably break the fabric of the universe:
I, a regular
Proposal to get a message offline is: Introduce an extra modifier hurtfull/discriminative. Once a message is marked that way once only, a message will be generated at one of the maintainers. He/she will look at it and disable/remove the message if it a valid moderation in that category. If is not a valid moderation in that category, extra hurtfull moderations will not produce extra messages.
I know this is way offtopic, just as the parent is, but something needs to be done about the grandparent messages.
Best regards,
Jurt1235
My wife's sketchblog Blob[p]: Gastrono-me
According to NASA the russian spacecraft Soyuz chases the station for two days before it docks. Considering that the Soyuz is the smallest manned spacecraft to dock with the ISS you gotta wonder how much of its total mass is fuel needed for that maneuver. According to the russian space web the total mass of the Soyuz at launch is 7.1 tons. The propulsion module takes up 2.6 tons of that. Note the amount of payload the Soyuz can actually deliver - 3 crew and 30kg. Less than 1% of the total mass. Oxygen aint that heavy. So other than the heat shield on the descent module (total weight 2.9 tons) what's taking up so much of the total mass? It's gotta be fuel right? So what happens if you gather solar power in space and use it to propel your orbiter? You could use a MagBeam to do it. All of a sudden you havn't got much to lift up to orbit. Just those nice light humans and some nice light oxygen so they don't suffocate on the way and a nice light inflatable heat shield so they don't burn up when you take them home.
But here's a silly question. Who says we have to take up a whole heat shield on every launch? We could send up parts of the heat shield, sew em together in orbit, tie together all the descent modules we've launched in the last 10 flights and send everyone home together.
The room for innovation in manned space flight is astronomical. We just havn't seen any because there's no motivation to reduce costs when your space program is funded by taxpayer dollars.
How we know is more important than what we know.
1. Because I know the orbital flight will cost 10x the suborbital and I'm not quite rich enough for that.
2. Because I'll be dead before they get the orbital vehicle ready for commercial passengers.
RETURN without GOSUB in line 1050
Then, when the materials tech becomes practical, they build a space elevator on the very same site. Makes perfect sense; at that point, they have the name and a shitload of capital to make it happen. Taxpayers have spent enough on incremental baby steps and aerospace subsidies.
May dreams such as these take wing and I'd be happy just to watch: (link)
"OH SHIT, THERE'S A HORSE IN THE HOSPITAL!"
With the funding available to these innovators, there is no reason why they cannot modify their designs as necessary. They have tremendous support and an enormous financial backing. I highly doubt they are only able to contemplate "scaling up" their current design.
9 c499bc-6dc0-4fb5-a21d-2d671861b42a
http://www.inaniloquent.com/PermaLink.aspx?guid=2
Is that few km up really such a big saver? Most of the energy for orbital flight is needed for getting the tremendous sideways speed needed to stay in orbit. I'm not having much luck with Google, but can you point at some stuff that shows the gains aren't more than a few percent?
I believe posters are recognized by their sig. So I made one.
Actually, the changes aren't that hard to make. The problem with the current engine design is that the hybrid rocket`s isp isn't high enough. Simply changing to another type of rocket doesn't help much though, the spacecraft needs to be an egg-shell filled with fuel in order to get to orbit, if there is no staging.
. html
The problem is that the exhaust gases from a rocket are moving at the speed of sound. You can get much more thrust from the same fuel if only that exhaust were moving faster. It turns out that Rutan has been working on a new type of engine (pulse jets) which does just this, see http://www.pw.utc.com/shock-system/flightsoffancy
for more details. Now if you work out the isp from these new power plants, they are just amazing. It cuts the mass fraction for fuel from 90% down to something like 50%, or even lower. (Remember, the rocket equation has an exponential term in it, so even small changes in thrust per unit fuel mass make a huge difference.)
Burt Rutan said in a recent conference that it requires three breakthroughs for orbital craft to be viable, and that he already has made one of them. It wouldn't surprise me at all if this is that one. (With the others being related to reentry.)
I have to agree that I prefer to buy products from (and work for) companies that tend to keep their PR under wraps until they actually have something to show for what they have been spending all of their R&D budgets. I have done too many projects that I call "design by press release", where my boss tells me what the product is supposed to do by sending out the press release, and they I have to try and shoehorn the project to meet those expectations (including customer expectations). It is never a good thing.
In the computer software industry, you can sometimes get away with that sort of mentality, but in aviation and especially rocketry I would say that is an absolute mistake. If I were running an aerospace company there is only one way I would dare make that sort of press release, and that would be if I already had the designs "on the drawing board" and had already proven most of the major technological hurdles (at least from a test lab viewpoint). Obviously Scaled Composites hasn't sent anything up besides SS1, and you (as well as others) are correct that SS1 by itself simply won't scale up to orbital velocities without some very substantial structural and raw materials changes. Essentially a whole new spacecraft from the ground up.
SpaceX I think has at least been doing the right thing, and they got a bunch of real rocket scientists that know their stuff. They will get to orbit (unmanned), and if their Falcon I is successful, the Falcon V has a very good chance of success. The Falcon V is also a "next generation" spacecraft, and does demonstrate what scaling in the aerospace industry is really all about. There are also no major "show stoppers" to the Falcon V other than government bureaucracy and idiots in congress calling it a "munition".
I see a number of things that will prevent a scaled up or modified version of SS1 from being successful as an orbital spacecraft. On the other hand, if you compare the DC-3 to the DC-10, there are some similar features between the two aircraft, but it also shows huge leaps of logic as the aeronautical engineers finally figuered out how to build aircraft. I'm willing to do a "wait and see" on this new design by Scaled Composites, but I am very skeptical.
we are building a spacecraft which should be better then our current one, and if we find out it actually works, then we will try to build one which is even better!!! seesh, talk about vapourware...
10 ?"Hello World" life was simple then
I take issue with the tone of this article, not the content. I do not doubt the accuracy of the information in the article at all, but there's a prevailing sense of: "NASA Knows Best".
Just because an organisation employs thousands of the brightest people it can find doesn't make their end product the best, it simply does not follow.
Beurocracy, design constraints, budgetary constraints and pure "can't think out the box" attitudes in large organisations tend to quash innovation. Not that NASA don't innnovate, of course they do, but if those individual bright people we're allowed to bring their own ideas to fruition there would be much more innovation. Not to mention that government agencies the world over are generally stifled by administration, that just further compounds things.
Again, the article is probably right in it's facts, but claiming that "Why SpaceShipOne Never Did, Never Will, And None Of Its Direct Descendants Ever Will, Orbit The Earth" (the article title) is like saying that linux would never be more popular on desktops than windows, or that desktop pc's would never outperform mainframes, or any other flippant claims about how the current way of doing things is the best.
In every industry I've bothered to look into there's is always at least one example of a small set-up coming up with something innovative that breaks all the established rules.
SS1 may have been it, it may not, but saying that it'll never happen is just asking to be proven wrong.
I'm under the impression that the direct speed/altitude benefits are fairly small. Rather, the main benefits are from safer abort methods (you can parachute back down if your engines fail) and being able to build an engine optimized for the upper atmosphere and space. You also don't have to pay launch site fees, and liability insurance becomes easier to deal with. Here's a relevant quote from t/Space's site:
n =projects.view&workid=CCD3097A-96B6-175C-97F15F270 F2B83AA
http://www.transformspace.com/index.cfm?fuseactio
The major benefits of air launch come in safety, simplicity and flexibility. Crew safety is enhanced because abort-at-ignition is easier when the capsule already is high enough for parachute deployment, vs. the on-the-pad challenge of releasing sufficient energy in the correct direction to send the capsule high enough for the parachutes to deploy. Public safety is enhanced because the launch takes place over open ocean, well away from any populated areas.
Air launch also allows simpler engines, which don't need to be designed to operate at both sea-level air pressure and at altitude. The "all-airborne" operation also reduces the performance penalty of using inexpensive low-pressure tanks and engines.
Flexibility and responsiveness is greatly enhanced by air launch. Most winds and precipitation at the airport runway -- launch site -- don't delay a launch; the carrier aircraft simply flies to clear weather. In addition, responsive launch often requires matching a particular inclination and orbit phasing. The carrier aircraft over open ocean can launch the CXV to any azimuth, and by flying across longitudes, can quickly match a desired orbit phasing.
The t/Space version of air launch provides only modest performance gains, in the 10-25% range, compared to a ground launch. It does not attempt technically difficult challenges such as accelerating the launch aircraft to supersonic speeds, or reaching very high altitudes.
Or, to put it another way (and miss-quote The Simpsons):
"It's just rocket science, not brain surgery."
Unfortunately, I am not Wil Wheaton
..the orbit, and come back to mother earth with out a scratch but does it run embbeded lin.. err OSx86 on VMWare... oh, wait - nevermind,
No, I don't think so.. he is wasting his money.
Getting the craft back down to earth in one piece is going to be the capability I am most interested in seeing them solve. Will it be ablative or something reusuable like the tile system but more robust? Being Rutan I full expect it to land like a plane on return so that alone will limit some of the choices he can make.
Unless he revolutionizes rocket propulsion I don't see how they are going to get anyone into orbit at reasonable costs, by reasonable I mean in the $1,000,000 range.
If space tourism would generate a good return on investment I am pretty sure the Russians would be all over it. They already have the technology to get there and have proven they would take paying customers. Since they haven't moved more aggressively I have seriously doubts if it is doable on todays technology. Look at the Kliper, the estimated costs are nearly $3 billion just to develop it! It can take 6 people and 750kg of cargo to LEV. The other issue that stands out with Kliper is that the module may only be used 25 times before retirement.
If the Russians are having such issues with LEV on that budget it will take a miracle for anyone else.
Wiki link to Kliper
http://en.wikipedia.org/wiki/Kliper
* Winners compare their achievements to their goals, losers compare theirs to that of others.
The writeup you quote compares the Shuttle engines with the Scaled Composites engine, and says the former are complex enough to do the job, whilst the latter is too simple. But don't the Shuttle's two strap-on solid fuel boosters supply 75% of the thrust at launch? In other words, the Shuttle has three wildly complex engines and a whopping external fuel tank supplying 25% of the thrust, and two relatively simple solid boosters supplying the other 75%. So, in that context, the Shuttle's engines can't do the job by themselves either.
You forget that SS3 won't have the high drag factor caused by hauling a huge bureaucracy around.
...and he grinned, like a fox eating shit out of a wire brush.
Who said it wasn't possible? Getting to 100km may have been an engineering challenge, but it was clearly achievable. There were about 20 companies competing for the X-prize. That was pretty good evidence for it being possible.
Who's saying that this isn't possible?
All people are saying is that the technology to get to LEO and back is considerably different from that needed to get to 100km altitude and back.
Not really related to the articl, but... I'm getting pretty annoyed by this "look at what this small company is capable of doing, while NASA wastes billions of dollars!". Hell, Rutan himself made some similar comments (was it on 60 Minutes?).
Yes, What Rutan/Scaled Composites did is great, no denying that. But comparing their budget to NASA's is ludicrous. Does Scaled Composites maintain orbiting space-stations? Does Scaled Composites build orbiting space-stations? Do they conduct scientific experiments on other planets and in space? Do they send probes to comets and Mars? Rutan and Co managed to put a spacecraft for a short amount of time in to edge of space. NASA did that in 1961.
Rutan and Co have the advantage of having the knowledge that NASA and others have accumulated over the years at great expense. They use that knowledge, and then make remarks how NASA is "wasting money". Well, without that "waste of money", SS1 would still be nothing but a glimmer in Burt Rutans eye.
Lesbian Nazi Hookers Abducted by UFOs and Forced Into Weight Loss Programs - -all next week on Town Talk.
There's some serious modifications though. More power. More speed. Heat shielding. Better efficiency. No doubt there are a few ideas that worked, and can be reused, but they're pretty much starting from scratch.
My guess is that Rutan won't be building SS3, though he may build WK3. The turbine powered first stage is a great success.
The orbiter will presubably be a pure rocket SSTO, carrying passengers only. Rutan doesn't have any demonstrated skills in this area so I don't think he will be involved.
http://michaelsmith.id.au
The business plans of these companies... to fund billion-dollar operations with the wallets of monied space geeks... is nothing more than Heinlein-addled wishful thinking. Most of the bazillionaires would much rather spend their spare time at the French Riviera, or their private Greek island or shopping in Hong Kong. There just aren't enough people willing to shell out megabucks to fund the R&D and operating costs of space tourism.
I mean, the Renaissance-era European explorers weren't wealthy sightseers who wedged themselves into tiny wooden deathtraps to sight-see. They were businessmen after profitable trade routes. Money lauched the Nina the Pinta and the Santa Maria, not tourism. Explorers werre invested in with the expectation that the money spent would return with a huge profit, not a nice story about the local food and colorful customs.
But! Sending techs up to deploy, retrieve or even fix sattelites in orbit... now that's real money.
That sort of work requires an orbital spacecraft with a decent payload capacity. So, this is a very good step in the right direction to making private space enterprise possible.
SoupIsGood Food
"I'm sure Virgin Galactic is hiding an International Virgin Rescue company somewhere in their corporate structure."
/.
No need for one of those on
An interesting article, but it seems to make a fundamental mistake in comparing Rutan's task to building a Space Shuttle, when reaching orbit will merely require building something that can do the job of Vostok 1, which was early 60s Russian technology.
The shuttle is big, expensive and hugely complex, with a very compact engine, but that's because it's a 10-seater spaceshiip, and has a *huge* payload bay. If all you want to do is get a small crew up there, and not take a 60ft by 15 ft 28,800kg satellite along too, the task is a lot simpler.
A pizza of radius z and thickness a has a volume of pi z z a
It's amazing how easy the SS1 folks make the achivement appear. Clearly the SS1 team had done their homework and benefited from what was learned in the X-15 program. Whereas the X-15 program built up speed and altitude flights slowly, with each pilot getting experience at every point, the SS1 made large jumps on each flight, often trading off pilots along the way. No doubt Mike Adams was smiling down on the SS1 flights.
It's great to see the private sector advancing technologies like this; what was so hard in the 1950/60's is easier with 21st century materials, engine technology and computer controls (BTW the X-15 was one of the first air/spacecraft to depend on 1st generation flight controls).
Hopefully the engineers at Scaled and Virgin know more than you (and the author of the linked page) do. Who's to say that a direct descendant of SS1 wil not (gasp!) change engine technologies?!
This as got to be one of the most stupid posts/pages that I've seen so far this year.
Branson already has his own island for a staging area - maybe that was phase 1?
Given current rates of launches per year, 25 launches before scrapheap is quite reasonable. You'd get a vehicule you could use years on end w/o expensive overhauls (read:shuttle) and simply scrap it after a predetermined # of launches or age, whichever comes first.
Of course, the temptation to keep using it beyond its designed lifetime will be there, esp. if that could save you a serious wad of roubles...
As soon as one of these private spaceships blows up, the media will make a huge deal out of it and big corporations will have Congress pass laws making the whole industry prohibitively expensive for the little guy. Then Lockheed, Grumman, GE, or whoever will buy up the little companies that blazed the trail and life continues as usual... the rich get richer, the poor get poorer.
Agreed - the Falcon people are much further along the road towards engines (in particular) of the type needed to actually make orbit. When Rutan has a Falcon-1 equiv engine (covered on Slashdot a while back), *then* I'll pay attention to the press releases.
"None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
It is a big fuel saver. The use of the fuel is non-linear, So when you can save some fuel by having a higher starting point with less drag, it also has a non-linear saving as result.
Just calculate the needed potential energy to lift the crafts total mass for 10km up in the air, and you know what basic savings you get.
I also can not seem to find an image of a rocket trajectory, so a description will have to suffice: The first few kilometer the trajectory is as straight up as possible. The trajectory in the densist air layers is the shortest possible. Since speeding up in that part is costly (drag=speed^2), the speed is kept down, in multistage rockets by coasting, or with solid fuel rockets by designing the thrust in such a way that you do not spend to much fuel on speed. Once the air density is low enough (less drag), you will speed up again, and adjust the trajectoy to get to escape velocity. For a decaying orbital trajectory, you do not necessarily need escape velocity, you just need to be able to make it around the earth like one time. So going orbital is also still pretty free in interpretation and goal.
New designs for suborbital planes with ramjets almost all use this design principle for this reason (and they need to get up to speed to make the ramjet work).
The main problem stays though that the design is complex, the take-off of a combined craft like this is slow, and the payload the combined craft can take is low, not higher than current rocket techniques if you really want to get into orbit (Imagine the shuttle+fueltank minus thrusters being lifted to sufficient height)
My wife's sketchblog Blob[p]: Gastrono-me
"When Rutan has a Falcon-1 equiv engine (covered on Slashdot a while back), *then* I'll pay attention to the press releases."
Why develop an engine from scratch when you're not an engine developer and there are dozens of proven engines you can just buy?
I agree. We really do need a revolutionary development in rocket design. That would make single-stage-to-orbit craft really doable, and significantly lower the cost of getting into LEO.
I too am curious to see what sort of heat shield he uses. I suspect it will be elegant and to the point, like many of his designs.
Time will tell!
Ignore Alien Orders
Without trying to sound cynical, I'm not too big on the idea of a company flying me into space. If you look at just the last month, we had a number of planes worldwide crash for various reasons. We've been flying for about a century now and there are still quite a few issues that bring planes down. I know people will say how you're more likely to die in a car crash than a plane crash, and that does have merit, but I'm just saying I don't want to be one of the early passengers on one of these new flights.
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Its like expecting DOS to scale up to a multi-threaded multi-user graphical operating system.
DOS
DOS with a GUI (Win 3.x)
GUI running on DOS (Win 9x)
GUI OS (Win 2K)
You see; it DID scale using stepping stones.
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The same way as SS1.
SS1 was a revolutionary design that, when coming back down, folded and came into the atmosphere like a shuttlecock, then when velocity was low enough, unfolded and landed like a plane.
Damned impressive engineering. No reason it won't scale from a 3 seater to a 7 seater.
How to make money with space tourism:
Don't charge much up front. People could ride for beans on one condition. Their life insurance policies get made out to you.
As I understand it the third working design in the series was always intended to be an orbital craft. First an X-Prize winner, then a larger passenger version for sub-orbital tourism, and then an orbital design. I've been hearing this pretty much from the beginning. So how is this in any way recent?
I'll tell you what they ought to do...they need to go back to all of the Sci-Fi books written in the sixties and collect the ideas promoted by the authors. Most of the authors were scientists in their own right and spent quite a lot of time researching what the actual details would have to be (within the then known facts and limitations of future tech). Spaceport location, for example, was a common topic that was investigated. I'm not saying that all of the ideas in those old stories are feasable but there's lots of good starting points. Might give one a leg up on the competition :)...
The NSA: The only part of the US government that actually listens.
Again, the article is probably right in it's facts, but claiming that "Why SpaceShipOne Never Did, Never Will, And None Of Its Direct Descendants Ever Will, Orbit The Earth" (the article title) is like saying that linux would never be more popular on desktops than windows, or that desktop pc's would never outperform mainframes, or any other flippant claims about how the current way of doing things is the best.
I don't think the issue is whether the current way of doing things is the best or not in those instances. Linux won't surpass Windows on the desktop in its various current iterations because it is not standardized.
Re: desktops outperforming mainframes (I'm not a computer scientist) - but I'm not aware of any desktop ever outperforming a mainframe.
Re: SpaceShipOne and its descendants. It was designed to solve a particular problem and it solved it. It doesn't even have avionics and computer control. There is NO way that SpaceShipOne, in its current iteration or derivatives thereof, would EVER reach orbit. It was just a proof of concept. To design an orbital vehicle will mean going back to the drawing board and designing an orbital vehicle - probably some form of dual engine vehicle (thick atmosphere engines and thin atmosphere engines).
I'm not certain, and I didn't google it, but I don't think any craft has achieved orbit from a piggyback launch. Has that ever happened?
un burrito me trampeó.
Also NASA's goal has never been to bring spaceflight to the common man (nor "common multimillionaire" for that matter). I'm sure they are quite content with their astronauts being considered heroes just for doing their job. The sooner astronaut is equivalent to bus or truck driver, the better.
I hope you're not talking about SS3 because you could not be more wrong.
The reason SS1 was so simple was because it didn't have reach the speeds needed for orbit. It went up and fell back down. Simplicity.
An orbital craft will need to reach much higher speeds. As a result when it reenters the atmosphere, it will have to bleed off that high speed somehow. Most reentry vehicles trade their speed for heat energy by using the atmosphere for braking.
Why is it that every time private space flight comes up, a segment of the Slashdot crowd goes off with their knees jerking every which way about how it can't be done?
There isn't enough information available to us to say if Rutan's plan will work. Most people here, myself included, wouldn't know what to do with that information even if it were available. Those who try to show-off their intellectual prowess by debunking that nonexistent information look like fools.
The paranoid little cynic in my head keeps shouting that the government-is-God crowd is afraid that private enterprise will slaughter their sacred cow.
There is no known God.
http://www.marxist.com/
May dreams such as these take wing and I'd be happy just to watch: (link)
Now, if only they didn't make the worlds only 'web-link-as-an-java-applet' page, which crashes my Opera (and looks beyond-butt-ugly), I might have learned something...
is that it will be the ones from the X-33. It was designed to be inexpensive and work better than the shuttles.
As to propulsion, he is first launching horizontally from an aircraft some 90-100K km up there and with sub sonic speed. He will probably have a simple H2/LOX rocket for boosting it from there. It will almost certainly be a standard engine rather than something new and innovative.
Keep in mind, that he is not going to be launching a shuttle. He is looking to send 3-6 ppl into space. Very little load. Probably just a capsule.
Any real innovations will probably come for cargo which will use a space elevator.
I prefer the "u" in honour as it seems to be missing these days.
Ok so the linked article is a little presumptious and arrogent, but it is far from the most stupid thing I've seen.
It is correct in pointing out the significant differences between what SS1 did and LEO. I think it downplays the significance of the accomplishment, and plays up "built to do a simple task" a little too much. After all Spirit of St. Louis was also specially designed just to do a "simple" task.
The fact of the matter is that the average American assumes that Rutan is just a few years from beating NASA at its own game, and this is not nearly the case. Private invention can only lead us forwards, and I don't think that what SS1 did should be wirtten off.
This article implies a non-sequitur conclusion - that since Spacecship 1 didn't go into orbit, it's not possible to do it better or ceahper than NASA has done with the Shuttle. Yes, it will cost much more than $26M to develop SS3, but I can't see how anyone could have built a "reusable" vehicle less efficiently. BAsed on blindly optimistic and untested assumptions (wich many knew were spurious), NASA went from drawing board to operational system in one jump, so we are stuck with 1970s technology and massive per-flight costs that devastate the NASA budget year after year.
the shuttle has been for some time (15+ years) now been known to be a massive failure. It came nowhere near its putative objective to provide cheap, routine space transport. It is neither cheap nor routine, and so has not found a market.
Let's compare apples and apples - could NASA have built and flown SpaceshipOne for $25M? No. They would still be working on it and would spend that much on paper studies easily. Is spaceship 1 and orbital craft? No. Is it possible to do much, much beter than NASA has done with the shuttle? Yes. Is machinery as complicated as the SSME at all necessary for cheap, reliable space transport? No.
Rutan has several things working for him: he has a small, talented team. He has few or no political constraints. Theirs is a low-ceremony culture (NASA thinks in terms of paper reviews). SC are masters at materials and airframe design, and they are very good and experienced at flight test - both strategy and tactics. I'm optimistic that they (or someone following after them) can take spaceflight to the next level - routine space tourism.
Space Elevators are probably necessary for the next cost plateau, but they are realistically 30 years away. Routine Virgin Galactic flights are probably 4-5 years away.
Helium balloons want to be free.
Not really. I heard Burt and Mike speek at Airventure in 2004. Burt breifly mentioned one of their prototype aircraft built for NASA. It was a very high altitude plane, and required a pressure suit for the pilot. The NASA team to support the "spacesuit" was larger than the Scaled team who designed, built, and supported the aircraft.
And while others here are bashing Scaled for simply repeating what NASA did back in the 60's I have a few words to say:
1) I don't see anyone else making real progress getting the public into space. NASA won't take you suborbital for 200K. Sure, only the rich can afford it now, but it is progress, and it is supposed to get cheaper.
2) Rutan does innovate: Carefree Reentry was never done before - in fact, the X-15 crashed because it reentered with improper attitude.
3) Scaled is making significant progress in a short time. Yes, they are on the shoulders of giants, but did you expect them to start with a moon shot or what?
4) If I ever get to space in my lifetime, even briefly, it's more likely to be in a vehicle designed by Scaled Composites than NASA. NASA can't afford it the way they operate.
5) When did NASA ever express any intention of taking ordinary people into space for fun? Oh right, never.
I still respect the research that NASA does, but someone has to put that to practical use and that's where they fall down.
How do I go about getting hired there? I imagine is a still a short corporate ladder.
The solid fuel boosters provide lots of thrust, but they fire for a shorter period of time and provide basically none of the orbital velocity. The SSMEs do all the real work of getting into orbit.
I have seen the future, and it is inconvenient.
The feather won't work. It needs an atmosphere to orient the vehicle, it won't have that until about 100,000 feet or so. And at very high mach numbers it will rip off instead of working. I think Burt knows that. At the AIAA Joint Propulsion Conference (addressing a bunch of aerospace engineers) he said it would be awhile before anyone could do orbital, and his suborbital craft obviously couldn't be upgraded to do the job.
So parent is obviously talking out of his ass when the man who designed the craft said it can't be done.
Plus, you'd have to throw thermal protection system (TPS) on it, and engines probably an order of magnitude larger to achieve the delta-v to hit orbit.
In order to keep the same model (slung-under-aircraft single stage rocket) you'd need a much bigger aircraft - Boeing 747 or one of those Russian (i forget the names). Sling load a rocket, sans feather. Most of your volume is going to be fuel. Get up to your service ceiling and pich up, release your rocket and BOOM.
(Also remember t/space = Burt Rutan & Scaled, and a few other companies ) Personally I favor SpaceX for orbital capacity although remember they only produce launch vehicles, not human-rated vessels. A second company will need to do that and purchase the launch services from SpaceX.
-everphilski-
Yes, I accept that, but the article referred to by the original poster seemed to be ignoring the existence of the boosters entirely. Who knows, a combination of "simple" throttleable and non-throttleable engines coupled with a high-altitude launch might be just fine: a 9-seater ship designed to stay aloft for an hour or two doesn't need a whole pile of stuff the Shuttle needs, ranging all the way from cargo bays, docking adapters, thermal radiators, sleeping quarters and experiment areas through to piddle tubes. Well, maybe keep the piddle tubes for Business Class.
Burt Rutan would agree with you. Virgin prefers to showboat.
-everphilski-
One really has to wonder why so many people fell for it... I mean: Can you make it any more obvious than setting your homepage to "gnaa.us"?
Come on, it's timecop we're talking about here. It's impressive to see they set up a page so quickly, but... Slashdot, you have been trolled.
Pulse jet? Isn't that nazi-era technology?
"comparing their budget to NASA's is ludicrous" -- not so. NASA has a bigger budget now. NASA's budget is finite and bounded by politics. NASA's actions do not affect its budget (except very indirectly) and cannot grow the budget.
By contrast Virgin Galactic will be operating for profit. That is, for every N they spend, they will get N+M back. Their initial budget is bounded by the initial N (startup capital), but it grows rather than decreasing with each thing they do. That means that given enough time and a sufficiently profitable business, their budget can grow to an arbitrary size. VG's budget can be, and eventually almost certainly will be larger than NASA's.
I think you forget that Scaled Composites did a lot of the research and engineering work for the McDonnell-Douglas Delta Clipper and Lockheed-Martin VentureStar programs.
While of course these projects were not completely successful, it did teach Scaled Composites a lot about spacecraft design; I think Burt Rutan's company has the engineering knowledge to eventually build their own private spacecraft that could reach even the International Space Station at substantially less cost than the proposed Kliper spacecraft that the Russians and Europeans will jointly develop.
The USAF already HAD a suborbital ship.
You really don't get much payoff for the first 10 km, unless you're going way too fast for 10 km. Get to 50-100 km or so, and more importantly to 6000-8000 fps, and it's time to jettison the first stage (which may make sense as an airplane).
The main benefit for low-atmosphere launch, as has been pointed out, it safe abort, but that turns into a bad tradeoff if you use liquid hydrogen as fuel (which you currently need to do to get to orbit), as the cooling apparatus is quite heavy and energy intensive.
Socialism: a lie told by totalitarians and believed by fools.
Right, but that doesn't mean the shuttle is in any way better engineering. It's a poor way to get 10 people into space, and a poor way to get it's cargo capacity into space. I have my doubts, but it's certainly possibly Rutan will deliver a better way that the shuttle for getting 10 people into space, as the shuttle really does that poorly.
Socialism: a lie told by totalitarians and believed by fools.
"I'm not certain, and I didn't google it, but I don't think any craft has achieved orbit from a piggyback launch. Has that ever happened?" Google for Orbital's Pegasus rocket: "First air-launched rocket to place satellites into orbit, using its carrier aircraft as an 'air breathing reusable first stage'"
That paper seems to make the argument that complicated is better without really explaining why.
Many papers have been written about how inefficient (in terms of weight to thrust) turbopumped engines are. It's even been said that the only reason the shuttles main engines burn from lift of to booster separation is that the thrust is needed to lift the turbopumps which wouldn't be necessary if the main engines were ignited at high altitude (ie booster burn out).
No, a hybrid motor may not take Spaceship 3 all the way to orbit, but bear in mind this kind of engine can have an ISP similar to solid rocket motors but has the advantage that it can be throttled / shut down and restarted.
It's not impossible to reach orbit with this kind of engine, it's just somewhat inefficient in terms of payload capacity for a given fuel load.
safe -> same
So much for proofing
Just about every rocket is orbital for some portion of its journey (unless it turns into a glider immediately after its engines shut off). It's just that the orbit intersects the surface of the earth - no big deal, really.
Air launch *seems* obvious, but in reality it doesn't work so well.
Okay ... every freaking time this subject comes up (which you all know is fairly often) at least part of the thread gets hijacked into a detour on re-entry heating and "how in the heck is Rutan going to solve that problem", etc.
... all you have to do is SLOW DOWN!
... "every action", etc. ... it takes as much energy to slow down as it took to speed up in the first place ... so it would take a LOT of fuel.) An ablative coating (on the Apollo Command Module) or the tile system (on the Shuttles) is a heckuva lot cheaper and easier than managing to get enough fuel on-orbit to slow the dang thing back down to near-zero.
... but that doesn't make it any less true!
... it just isn't so. As is the case with many science problems, there is more than one way to skin the cat.
IANARS, but I do know a thing or two about aerospace principles and technology due to the education I *do* have. What I always find amusing about this particular area of the discussion (re-entry heating) is that everyone posting seems to take for granted that re-entry heating is an axiomatic phenomenon that MUST be faced head-on. (Pun not intended but noticed.)
THIS IS NOT TRUE!
The only reason re-entry heating is an issue for us (NASA, et al) is more a matter of ECONOMICS than technology.
The simple fact is that you can re-enter the atmosphere with little or no heating
The reason we don't slow down is we can't afford to carry enough fuel to get into orbit and still have enough to slow the craft down for a cool re-entry. (Think about it
In a nutshell - if I can slow my craft down enough (think "retro-rockets" here) then I can practically "float back down" into the atmosphere with minimal heating.
There *are* possible solutions, such as *sending* fuel to orbit in a separate un-manned craft, and then re-fueling the manned craft on-station. Or *manufacturing* fuel outside Earth's gravity well so craft can re-fuel. Or having some other means of power to use for "retro-thrust" in orbit.
Now, I am going to cap the preceding comments with a BIG disclaimer:
*Of course* I realize that this opens a different set of problems and perhaps presumes technology developments in other areas
I am just tired of people assuming that no matter what you do you have to have a craft capable of withstanding all of that horrible heat
Me out!
See you space cowboy
One of the things that make the shuttle main engines so complex is their design criterion of working from sea level to orbit. That necessitates a very high pressure engine. Launching from high altitude makes engine design much easier. If you drop the use of liquid hydrogen, it gets easier still. Still, you will need something quite different from SS1's hybrid, and likely more complicated. But the complexity of a shuttle SSME isn't required for reaching orbit, plenty of simpler rocket engines have done that.
Millikan measures electron charge with oil drops.
Tag lost or not installed.
Nope, it's even older. Wikipedia doesn't give a date, but the guy who invented pulse jets died in 1905 so they must have been around well before WWII...
0 1 - just my two bits
SpaceShipOne is currently at the Udvar-Hazy Center at Dulles airport. I went there a couple of days ago and recognized it under a blue tarp by the hangar doors near the Concorde. It's a shame they don't uncover it, you can get pretty close to it. I guess they want to have a big unveiling when they move it downtown. http://www.spacealumni.com/index.php?option=com_co ntent&task=view&id=218&Itemid=9
My boy, my boy!
Just looking at what t/Space is thinking of doing, Scaled Composites is building a reusable capsule that spashes down in the ocean. Makes rentry easy. Just fall and aim for the blue part. The Heat sheild will apparently be an ablative, but can be used for 25 flights, and ther will be 2 layers. Once the outer layer is used up, you pop it off and slap on another one. The capsule itself does that famous "shuttlecock" thing when falling back into the atmosphere, making it mostly automatic.
,probably, charge your first customer the full cost cost of the rocket to pay for it, then offer discount services to those who want to trust a used vehicle.
Reasonable costs are achievable. But apparently you can't spend 100 million dollars per launch on a disposable rocket and do it. If you spend 100 million dollars on a reusable rocket and then get to use it 100 times, then the cost starts drop. 200 times and costs really start to drop. If the rockets can be used on the level of a commercial airliner, then even us poor working saps will be able to take a ride.
Given the current launch market, you could
If Mr. Edison had thought smarter he wouldn't sweat as much. --Nikola Tesla
SS1 performs worse than the V-2 (V2 had roughly twice the payload (counting SS1's cockpit as payload as well as its passengers, and assuming a combined mass around 500kg), and twice the delta-V), let alone Vostok. Yet, the V-2 was at the birth of modern rocketry, and was pumped out in huge numbers. Not that a determined small private company can't reach orbit (determined large private companies reach orbit all the time :) ). SpaceX is pretty darn close at this point, for example (although they don't have to worry about reentry). Scaled isn't, however, and SS1 is completely the wrong direction for reaching orbit.
There is nothing fundamentally stopping Scaled from reaching orbit; on the other hand, there's nothing fundamentally stopping Pizza Hut from reaching orbit either, and the only major thing that Scaled has over them is general avionics experience (which they excel at, mind you, even if they're a bit risk-prone with their testing regime). What technical knowledge can Scaled take away from the SS1 program to an orbital craft that they didn't already have from aircraft work? Part of their flight control software, a bit more experience on pressurized cockpits, and validation of their CFD models. Anything else? I suppose if SS3 is air-drop, some of the craft-separation knowledge might be applicable, although they'll need far better ISP if they want to air-drop to orbit (even better than they'd need from the surface, since carriers can't scale infinitely well). Perhaps if they can demonstrate some reentry technology, or partner with a serious orbital contender like SpaceX, they might be able to be taken more seriously.
As for the article: the Shuttle comparison exists primarily because most slashdotters compare SS1 to the Shuttle. Notes about how an SSME isn't needed to reach orbit (but an engine more complicated than SS1's SpaceDev hybrid is) were added specifically to address this issue.
Mind you, I take issue (as do most of the people here) with the design of a man-rated craft that caries tens of thousands of kilograms of payload, but only a little over half a dozen people. Part of this design issue was overoptimism when the program began - not realizing how high maintenance would be on a first-generation reusable, the numbers predicted for launch price per kilogram made it seem like they'd want to use the shuttle for everything, and since they only had the budget for one craft (underbudget at that...)
Are there any deer in the theater tonight? Get 'em up against the wall.
Exactly - I don't know what the top speed of SS1 was, but I know it wasn't anywhere near the 7 Km/s (about 15,000 mph) that you have to have to orbit the earth in LEO.
It's a huge job getting to that speed, and it's another huge job to get back down from it. SS1 isn't a good indicator for either of them.
t/Space has asked for $400 million to develop this system, to be completed by 2008. After that, it would cost about $20 million to launch a mission. This date is far in advance of the 2014 date (or the 2010 date) proposed for the CEV.
Given that a space shuttle mission costs over $800 million, this seems like a great idea for a human-only shuttle. It would be inherently more reliable than the shuttle, much less expensive per launch, and really open the doors to private sector investment in space since NASA would contract t/Space for each launch. Cargo could be sent up separately on a heavy lift rocket that need not go through the enormous expense of human rating it.
Stephen
The saving is SFA compared to the kinetic energy required.
1 kg mass at 10 km height = 98.1 kJ
1 kg mass at 7600 m/s = 28.9 MJ
Wow, your potential energy saving is 0.34% of the kinetic energy.
Actually, Scaled Composites does have experience in each and every one of the areas listed.
1) low cost reuseable engines: The Scaled hybrid engine is mostly reuseable, and was designed mostly in house by Scaled Composites.
2) low cost reusable ablators: The ablators on the leading edges of SS1's wings are a propritary Scaled design that is far cheaper, lighter, and more effective than any other system.
3) "Flight test experience is irrelevant". WTF?
What about the discussion do you feel is lacking? I will gladly elaborate. "Complexity" is a general term so that you don't have to keep referring to things like regenerative cooling, efficient fuel/oxidizer mixing, high pressure combustion, large expansion ratios, etc.
;) The tank mass is ridiculous in such cases. If you're not referring to either of these cases, what is your proposal for maintaining engine pressure?
inefficient (in terms of weight to thrust)
The highest ISP engines by a significant margin are turbopumped. What would you prefer, solids, in which your entire fuel tank needs to be able to handle the pressure of combustion? Solids can get you to orbit, but it takes more stages and/or a worse payload fraction. Or, don't tell me that you're referring to self-pressurizing tanks
The reason that the SSMEs burn from lift to ET separation (they burn past booster separation) is because you want to accelerate as quickly as possible. The longer you have low/no horizontal momentum, the longer you're suffering high gravity losses. SSME turbopumps handle 160,000 W/kg, the highest of any turbopump in existance. The mass of an *entire* SSME is only 3,177 kg - this includes four turbopumps as just part of the total mass. At launch, SSMEs form just 0.47% of the total mass. Even at burnout, they're only around 7.5% of the total system mass. For a rocket engine, that's pretty good.
Are there any deer in the theater tonight? Get 'em up against the wall.
Consider that an ICBM is simply a sub-orbital rocket with a dangerous payload, and you begin to realize why governments are so touchy about the export of this technology.
A person jumping is also in a highly elliptic orbit passing rather close to the center of the Earth.
I don't understand how your description of infinite stages is not a single stage? Imagine that you build a solid rocket that was built out of rocket fuel (or a casing of relatively negligible mass) so it spent itself as it burnt... would that count as one stage or infinity? To me that would seem more like a single stage rocket.
Of course, IANARS.
If space tourism would generate a good return on investment I am pretty sure the Russians would be all over it. They already have the technology to get there and have proven they would take paying customers. Since they haven't moved more aggressively I have seriously doubts if it is doable on todays technology.
I think part of the reason why the Russians haven't sent up more tourists is because of the 6 months of training that are required. I'm sure many millionaires aren't up to that task however interesting it may be.
I am becoming gerund, destroyer of verbs.
1) Scaled did not build their engine. They bought it from SpaceDev. It performs too poorly for, and really cannot scale up to performing well enough for, orbit.
2) SS1's peak heating was a mere 600 degrees. Real reentry vehicles experience 10 times the total heat load. The difficulty of dealing with temperatures isn't even close to linear. That's the only reason why they could use a cheap, thin spray-on ablator on top of a regular airplane-like composite skin. Even without the ablator the craft would survive, but it'd be damaged.
Real spacecraft have to either have thick ablators carefully inspected against cracks, or very effective heat radiation, in addition to a skin/surface that takes much higher temperatures (1200-1400C, and the difficulty of taking those temperatures is far from linear) and often channels it to a heat sink. No matter how you do it, it's a lot heaver, more complicated, more expensive, and damage is a very serious life-threatening risk.
3) Well, if you're flying a very different behaving craft, as a real orbital rocket would be... I wouldn't say SS1 flying experience was "irrelevant", but it wouldn't be extremely relevant.
Are there any deer in the theater tonight? Get 'em up against the wall.
My crazy idea would be to slow down the vehicle while it's not in the atmosphere. This is where it gets whacky. I imagined a shuttle that would let out a ceramic weight made out of the same material as the shuttle tiles and have it attached to the vehicle with a tether which would also have to beable to withstand the heat. This weight would interact with atmosphere and slow down the vehicle while the vehicle would have the benefit of slowing down and not heating up as much as the weight.
Treat me like a marketing stat, and I'll treat your movie like a series of ones and zeros
"1) Scaled did not build their engine. They bought it from SpaceDev. It performs too poorly for, and really cannot scale up to performing well enough for, orbit."
You are mistaken. Scaled designed the engine layout and built both the liquid fuel tank and the composite solid rocket motor tube. SpaceDev and ECS manufactured designed the ignition systems.
Burt himself has said many times that SS1 will not scale to orbit! It is a research vehicle like the X-15. But the experience gained in the SS1 and SS2 programs will translate into orbital hardware, and sooner than anyone thinks.
Burt said at the EAA Connevention that he needs "three breakthroughs to go to orbit" and that he has made one of them. He is confident that the problems can be solved.
Remember, Rutan wants to make both suborbital and orbital vehicles that can be certified to a level of safety equivalent to early airliners. These will be 100x safer than the Shuttle, and will operate at a profit.
"I have to agree that I prefer to buy products from (and work for) companies that tend to keep their PR under wraps until they actually have something to show for what they have been spending all of their R&D budgets."
Then you should really admire Rutan. He didn't announce SS1 until he had all the major components built and flying. He has a 30 year track record of not disclosing a new design until it is flying or nearly flying.
Note that the mention of SS3 came not from Rutan, but from Richard Branson, who is a scaled customer.
Rutan mentioned recently that he has a number of customers with interests in space flight, but "Virgin likes talking to the press more than the others".
Current Russian orbital rockets do not use LH/LOX engines. They use Kerosene/LOX, just as the first stage of the Saturns did. LH is not required for orbit, particularly for small payloads like a short duration manned capsule. To put a large payload like the shuttle or a moonship into orbit, you are probably going to need the higher impulse of LH, however.
You can only drink 30 or 40 glasses of beer a day, no matter how rich you are.
-- Colonel Adolphus Busch
You're depositing energy into three things: Air resistance, gravitational potential energy, and rotational velocity.
AFAICT, air resistance is a huge fuel waster at low altitudes because achieving high speeds in thick atmosphere will tear off the skin of the rocket. So you use just-over-mass thrust or a staged approach where that is what it averages out to at low altitudes, incredibly wasteful (think how much fuel a model rocket would take, instead of pushing skyward as fast as possible, to hover upwards at a max of 1ft/second because it would fall apart at 5ft/second). By using efficient airplanes to overcome low altitudes, you can use a full-on rocket stage right from the start.
Next.
It is useable for an orbital system? No. Is it scaleable for an orbital system? No.Next.
Is the flight test program of an orbital craft anything like that of an aerodynamic craft? No.Three strikes.
The problem is that the exhaust gases from a rocket are moving at the speed of sound
Time to stop reading here. Still, it would be entertaining to watch you "work out the Isp from these new power plants..."
Burt Rutan born in 1943. The X-15 project started in 1953. The X-15 first flew in 1959.
So, if Burt was one of the engineers on the original X-15 team, he was 10 (perhaps 9) when he joined.
He's quite a remarkable man, isn't he?
http://lkml.org/lkml/2005/8/20/95
http://www.spacedev.com/newsite/templates/subpage3 _article.php?pid=411&subNav=11&subSel=3
"SpaceDev has been playing a significant part of the SpaceShipOne team, working to develop safe rocket propulsion system for the space ship. SpaceDev has used its extensive propulsion experience to design and build all the key parts of the rocket motor, including the main valve, the advanced injector and motor igniters in addition to electronics and software. Work to-date has resulted in successful test firings of SpaceDev's hybrid propulsion system that uses Nitrous Oxide (Laughing Gas) and HTPB (tire rubber) as the propellants."
Yes, it wasn't a complete system (they didn't, for example, provide the casing), but they did the serious work on it.
Remember, Rutan wants to make both suborbital and orbital vehicles that can be certified to a level of safety equivalent to early airliners. These will be 100x safer than the shuttle, and will operate at a profit
And I'd like to be the queen of all Londinium and wear a shiny hat.
Are there any deer in the theater tonight? Get 'em up against the wall.
If you mean passive steering by aerodynamics, Shouldn't that be 'never done before with a winged vehicle'?. I believe that all the capsule-type spacecraft do this.
Wrong. What makes you think hybrid couldn't be used as part of an orbital system? And the bottom line is that its a rocket motor that required real rocket science to design and implement. SS3 may or may not use a hybrid motor, but it will certainly benfit from the rocket scientists that Burt is growing.
2) low cost reusable ablators: The ablators on the leading edges of SS1's wings are a propritary Scaled design that is far cheaper, lighter, and more effective than any other system. It is useable for an orbital system? No. Is it scaleable for an orbital system? No.
The correct answer is of course 'yes' to both questions. Keep in mind that Rutan is a materials engineer. He's forgotten more than most materials engineers ever know about making composite aero-structures.
3) "Flight test experience is irrelevant". WTF?
Is the flight test program of an orbital craft anything like that of an aerodynamic craft? No.
Wrong again. Both the X-15 and SS1 were a whole lot like oribital spacecraft, and the infrastructure and experience to test either of those is all directly relevant to testing higher performance craft. Certainly the test pilot community has recoginized the Scaled Composite test team with multiple awards and recognition. The Scaled chief pilot, Doug Shane, is president of the The Society of Experimental Test Pilots.
Ok, reading #3 above, I've gotta ask: this may be a totally naive question, but since IANARS- what if instead of lighting retro rockets to break orbit and dropping into the atmosphere at better than mach 20, and relying on friction to slow us down, (and as you mention, relying on relatively fragile ablative plating)... Suppose you have a craft with enough fuel/big enough engine to not only break orbit, but to slow down enough to maintain reentry at a managable temperature?
For example, your braking maneuver would start with purely retrograde thrust... as the spacecraft's vector begins dropping earthward, maintain the braking in the opposite direction, pushing against both gravity and the prograde movement. Go into the atmosphere at a managable rate of speed, and you wouldn't have the heating problems of 6000'+, you'd get to pick the temp. you want based on how much braking thrust you build into the system. So, you want to come in at 1000km/hr? 500km/hr? Just build the engine and launch the propellant.
This seems reasonable to me, it's just needing to launch the weight of the extra fuel and possibly larger engine into orbit that causes the problem.
Rutan "doing it" for NASA-scale sums would, as others have pointed out, be no biggy. The reason it'd be a big deal if he managed it on a commercial basis will be that it's 'commercial' not a sense other than 'launching LEO communication satellites for a few hundred million dollars a pop'.
Clue: Have you any idea *why* Delta or Arianne launches cost 8, 9 or 10 figure sums?
"None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
The article you refer to was written by a /.er with the handle of Rei who is the most mindless pro-NASA whore I have ever seen. At one point she claimed that crystals grown on shuttle missions had been used to invent certain forms of insulin. Of course the fact that these forms of insulin (Lente and NPH) which had actually been on the market for decades before the first Shuttle launch.
The big advantage of Scaled Composites and the other rocket shops is that they aren't big, stupid, brutally inefficient, Soviet style bureaucracies like the NASA manned space flight program is. Jerry Pournelle has some good ideas on how to fix NASA and get us back into space without spending much more money than we do now. Unfortunately implementing his ideas would cost lots of NASA employees their cushy jobs and would break up the monopoly cartel that Boeing and LockMart have on launch vehicles, which is something that Congress, which gets lots of money from Boeing LockMart, isn't going to allow.
cheap labor conservatives - they want to keep you hungry enough to be thankful for minimum wage.
Way to use those linear equations in what the parent was already saying is a non-linear equation. Just for comparison, combustion of a gallon of gasoline releases 125 MJ. You figure you can get to orbit for a gallon of gas per 5 kg of payload though? Okay, you'd need LOX, too, so throw in some of that. You're saving the drag where the air is densest. You also don't have to carry the fuel to overcome that first 10 km, and don't have to start off carrying the fuel required to carry that fuel for the first 10 km.
The article ignored the boosters because it isn't about the Shuttle.
f _a_Delta_IV_Medium_rocket.jpg is a picture of the second stage of a Delta IV, which is a reasonably modern rocket that lifts a much smaller cargo into orbit than the Shuttle. This is a cargo rocket, not certified or intended for manned use, and not reusable. It's not a simple engine, either, though it is much simpler than an SSME.
There's a feeling around Slashdot that orbital launches aren't really very hard, that you could get to orbit with a simple vehicle, and the reason NASA has budget and safety problems is (alternately) that they are too careful or that they are not careful enough.
As for the boosters -- the boosters are simple because first-stage efficiency doesn't matter all that much. Upper-stage efficiency cascades down through the entire system, making it larger and more failure-prone. If we replaced the SSME and ET with a simple (and very heavy) solid rocket, we'd probably need a Saturn V to lift it 20km.
http://en.wikipedia.org/wiki/Image:Second_stage_o
It's easy to suggest that rockets should be simple. Both government and large private corporations have put tremendous amounts of engineering work into building simpler rockets. It's not easy to do, and while other Slashdot posts claim that Rutan has some kind of engine breakthrough that he's keeping a secret, there's no reason to believe that.
I have seen the future, and it is inconvenient.
It is most certainly possible. The problem, however, is that you have to add even more stages and get an even worse payload fraction. For a shuttle analogy, picture the size of the shuttle compared to its launch stack, and then picture the orbiter shrinking down that percentage again with additional "braking" stages replacing the bulk of what used to be the orbiter.
Are there any deer in the theater tonight? Get 'em up against the wall.
Uh. Rutan is partnered with Virgin. Yet he and scaled composites are also a member of t/Space. How can they compete against eachother?
I just found the box to change my sig. Um.... [timeless witticism].
Actually, that's a good point. SS-3 doesn't need LH - though they may go that way just to make other choices easier, I suspect they'll again pick a fuel optimized for ease of ground support over ISP.
Still, it wouldn't surprise me if SS-3 was launched from something like SS-2. Once you can do high-payload suborbital flights, there's a *lot* of payoff for launching from 50-100 km instead of 10 km. And if suborbital flight turns out to be commercially viable, Virgin will want that high-payload launch vehicle for other reasons, so it's all good.
Socialism: a lie told by totalitarians and believed by fools.
Lots of people in this thread are complaining about the Shuttle, which isn't relevant at all. I suppose because you use the SSME in your comparison, everyone acts like you are demanding that Rutan build a Shuttle, and that gets them going on about how the Shuttle's problems are all caused by NASA, etc.
Perhaps you should refer to some smaller modern cargo launchers? The Delta IV, for instance, includes a brand-spanking-new lower stage, and it still costs plenty to launch. Though the LOX/LH2 lower stage makes for really beautiful launch photos which are almost worth the $150 million.
I have seen the future, and it is inconvenient.
Probably wise - I mainly did a Space Shuttle comparison because that's what everyone around here wants to compare. I won't have time to touch the article for another couple weeks, though.
Are there any deer in the theater tonight? Get 'em up against the wall.
The obvious design change is a swing wing. You need the wings to not produce too much drag during launch in order to get up to the speeds needed, so you'll probably have them folded back most of the way.
During landing, AFAIK, the larger the surface area, the more gradual the descent angle should be, and thus the less heating you'll get. (This assumes you descend quickly enough that you don't end up skpping off the atmosphere like a stone across a pond, of course, but....) Anyway, if you can slow the descent angle enough... say a dozen times around the planet before you enter usable air space instead of---what does the shuttle do... about half an orbit from deorbit burn to the ground, give or take?---less than one time around, you would see a lot less surface heating... I think....
Just a thought.
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It uses magnetic drag to slow the spacecraft.
Unfortunatly, you fall out of orbit before shedding enough speed to reduce the amount of thermal protection needed.
I think SC also takes away the validation of the concept air-dropping a space vehicle. While not a pioneering effort (X-15 did this), it is new (re-discovered?) in modern times because of the efficiency and cost-savings -- something NASA and various other foreign space programs haven't focussed on. This is something that private industry will always be better at.
Rockets are least efficient in the lower atmosphere because instead of taking the oxidizer from the atmosphere around them they carry it up with them. Once the atmosphere is sufficiently thin this is the only way to go.. but in lower atmostphere, the air-breather has a huge efficiency advantage.
Maybe a future step would be to go even higher with the air-breathing first stage where the vehicle runs up at scramjet-only altitudes before releasing it's space-bound piggyback craft? I'm sure supersonic separation of the spacecraft would be tricky, but that's a different problem...
The article you refer to was written by a /.er with the handle of Rei who is the most mindless pro-NASA whore I have ever seen.
That's pretty harsh. I mean, I get into arguments with her all the time and think she's biased about certain things, but when it comes to aerospace, she's one of the most knowledgeable folks around here.
The big advantage of Scaled Composites and the other rocket shops is that they aren't big, stupid, brutally inefficient, Soviet style bureaucracies like the NASA manned space flight program is.
Agreed.
Ugh, that web site is little more than childish NASA worship. Examples:
- Nuh uh! It went into space!
- Here's the SSME (Space Shuttle Main Engine):. Complicated, isn't it?
- Rutan, on the other hand, nearly killed his test pilot by launching in high wind shear conditions, and launching before resolving the cause of wild rolls at rocket ignition.
Etc., etc. The page is dripping with such - ignoring counter-examples that are successful and distorting historical fact (look it up for yourself - don't believe what I type any more than what that web page purports to be truth).
Cheers,
Chris.
Space agencies around the world have long been focusing on how to make the atmosphere a benefit instead of a hindrance. Hence all of the work on scramjets and many proposals for dual (or triple) propulsion craft (turbojets, ramjets, rockets, etc on the spacecraft), as well as the numerous external craft assist methods**. Orbital - one of the big space contractors - already uses air drop (wing).
;)
The main issue is that extra engines cost a lot of money, and that if a carrier craft is used, it generally must be much bigger than the craft that it carries. Since airplanes only scale so far before structural support mass requirements start becoming a serious issue, you're stuck with small craft like the Pegasus unless you can have a very high ISP spacecraft. While the atmosphere is an impediment for a rocket, it's usually not a mission killer - the biggest challenge is the 7,800 m/s orbital velocity that you need
** - There are other launch methods than a belly-stowed drop like SS1. Here is a mostly comprehensive list.
Carry under fuselage:
+ Provides even weight distribution on the carrier
+ Not very geometrically constrained
+ Spacecraft doesn't carry its fuel on the ground
- Requires a custom-designed carrier craft unless the spacecraft is very, very small.
Carry above fuselage:
+ Not very geometrically constrained at all
+ Spacecraft doesn't carry its fuel on the ground
- Difficult to separate with non-winged spacecraft
- Requires a custom-build carrier craft to avoid a tail collision
Wing carry:
+ No special aircraft needed
+ Reasonably small modification to existing airplane
+ Spacecraft doesn't carry its fuel on the ground
- Fairly geometrically constrained
- Unbalances carrier aircraft
Tow launch, no fuel line:
+ Geometrically unconstrained
+ Easy separation
+ Minimal towing craft modification
- Craft carries its fuel mass on the ground, requiring stronger landing gear and other structural support.
Tow launch with fuel line:
+ Geometrically unconstrained
+ Easy separation
+ Minimal towing craft modification
+ Spacecraft doesn't carry its fuel on the ground
- Additional step of transferring fuel midair needed
Dock-and-fuel:
+ Geometrically unconstrained
+ No separation
+ Reasonably small fuelling
+ Spacecraft carries only a small amount of its fuel on the ground
+ Can theoretically reenter, fuel, and leave the atmosphere without landing if maintenance can be reduced.
- Additional step of midair docking
- Additional step of transferring fuel midair needed
"Stow" launch (spacecraft inside carrier, launched out back with a drogue chute):
+ Spacecraft doesn't carry its fuel on the ground
+ Moderately easy separation
+ Some aircraft require essentially no modification
- Very geometrically constrained
Are there any deer in the theater tonight? Get 'em up against the wall.
"Obviously Scaled Composites hasn't sent anything up besides SS1, and you (as well as others) are correct that SS1 by itself simply won't scale up to orbital velocities without some very substantial structural and raw materials changes. Essentially a whole new spacecraft from the ground up."
The past ten years SC have been involved in building at least four different orbital space craft: they built the aeroshell and aerodynamic control structures of the DC-X 1/3 Scale Demonstrator for McDonnell Douglas, and entirely built the Roton test vehicle for Rotary Rocket and the X-38 Crew Return Vehicle for NASA. These programs died because funding dried up.
However, you would still be right (if entirely beside the point) that "Scaled Composites hasn't sent anything up besides SS1", if it weren't for the wings of the Pegasus rocket SC builds for Orbital Sciences, a rocket which has succesfully flown to orbit dozens of to times.
You may not trust in the space faring abilities of Burt Rutan and his team, but the space corporations of the USA do. Guess who I am going to believe.
It's not the world's only "web-link-as-an[sic]-java-applet". And I don't think they made it: I'm pretty sure it's actually just a standard Frontpage component.
...to create PowerPoint slides that make it to orbit.
Most people don't realize that t/space and Burt Rutan are one and the same. T/space has prototyped and is creating an alt.space orbital craft, and has Rutan's design style and fingerprints all over it. I'll bet strong money that the design mapped out by t/space will be what SpaceShipThree basicly is. I've blogged more about this in the past at:
a tives-to-nasa-transformational.html
"Alternatives to NASA: Transformational Space":
http://codinginparadise.org/weblog/2005/08/altern
That blog post points to videos, design documents, and opinions on what might be a preview of a SpaceShipThree-style craft, mapped out by t/space today.
What proof could the company possibly provide that they actually want to get me to orbit? The only way for the company to make money is to kill me.
As well, most life insurance policies have various hazardous activities clauses (for example, if you die while sky diving tough.). This scheme would not last long.
I agree Naruto is inappropriate.
The best education consists in immunizing people against systematic attempts at education. - Paul Feyerabend
Ummmmm.... how about doing a really serious deorbit burn to kill off a lot of that forward speed BEFORE hitting the atmosphere.
Any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so.
"... on the other hand, there's nothing fundamentally stopping Pizza Hut from reaching orbit either..."
/. article on it.
Well actually they did sorta. At least they paid the Russians some huge fee to paint thier logo on one of the rockets Russia sent to the space station.
I seem to recall there was a
Mycroft
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You would need fuel for this!
Most reentry vehicles trade their speed for heat energy by using the atmosphere for braking.
Totally unqualified fabulating follows:
Would it be feasible to do this in the reverse of the normal way: in stead of a shield in front of the vessel, use a drag-anchor behind it with vastly more drag than the vessel itself so the vessel only experiences moderate heating (sort of like a parachute for extremely high speeds, discarded in favor of more comventional braking once the worst risk of lethal heat levels has passed).
The anchor could acceptably become extremely hot and maybe even burn up, because there are no people or equipment inside. I guess creating an attachment mechanism that would hold up might be a problem.
sudo ergo sum
Which means that the entire SSx line is really a dead end, since they aren't going to do anything for getting bulk to orbit more efficiently. These craft are like Jet skis -- nice toys for the rich, but of little interest to the trucking or airline industry.
You can only drink 30 or 40 glasses of beer a day, no matter how rich you are.
-- Colonel Adolphus Busch
Look, I am certainly a "fan" of Scaled Composites, and I think that Burt Rutan is a very skilled aeronautical engineer. I was not aware of Rutan's involvement in the Pegasus rocket (this is the first time I've seen it mentioned, but then again I am not a deep insider of the hard core aerospace industry either.) I was aware of the Pegasus, and it is a neat design.
It is still going to be an engineering trick to move from either the Pegasus or SS1 into an orbital vehicle, and I think that there is going to be a bit of a struggle to get there. Just like aviation companies who build commercial aircraft make mistakes as well. Not all commercial aircraft are successful, although in the current market one bad mistake in an aircraft design can financially ruin a company, so they are very reluctant to make huge technological leaps and changes. That is precisely what Scaled Composites are doing.
BTW, this "news" about Rutan going into space is really old news anyway, as Rutan himself made a casual remark about orbital spacecraft (and perhaps even mentioned SS3 by name, but I'm not sure) during his interview by the American CBS television network TV show "60 Minutes". Rutan showed off his space station plans on the show as well, showing that he intends to eventually get into competition with Robert Bigelow as well. The orbiting swimming pool I thought was the neatest thing of all in the interview, by describing what it would be like to go swimming at 0.3 G's (Martian gravity BTW).
Overrated? How can it be OVER rated at -1.
Is this place modded my monkeys? So you were not impressed with what I have to say because I get more than you? Well just ignore me little man.
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No doubt. But do I gain compensating advantages, as in needing less of a heat shield, or one that's simpler to build and require less high technology?
Any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so.
I do admire Rutan for the most part. He has a very successful company and a very well proven track record. It is too bad that the current Virgin Galatic guys don't share that same philosophy, but then again they are PR people and salemen at the moment, not engineers that have their nose to the grindstone.
As an engineer myself, sometimes I'll talk to a saleman to try and get customer's reactions to certain product lines and future concepts. During that conversation, sometimes I "leak out" a little bit of what we are doing in engineering. Unfortunately and through years of sad experience, most salesmen can't keep secrets even if their life depended on it (and it sometimes does), so to an especially good client who has been doing a lot of business with the saleman (with a huge commission going to the salesman as well) they will sometimes "spill the beans" about new product ideas before the concept has matured completely. I think this is exactly what has happened in the case of Virgin Atlantic.
That is for the most part a very good sign for Scaled Composites because once they do have a working product, I have no doubt that Virgin can sell the seats. The only unfortunate part is that it may put some unnecessary time pressure on Scaled Composites to try and get SS2 into production before its time. Hopefully Richard Branson (the guy most likely to mess things up right now in the wrong ways) knows how to keep that pressure off Rutan & Company before the product is in production. Rutan also appears to be a very capable engineering manager in all of the right ways, and is likely to deflect a lot of this pressure as well.
Yeah, I thought that'd be the case.. I'm really rusty on my physics but after I wrote that I was thinking that you'd need expend a large amount of energy to try and cancel what you put into getting up to orbital velocity in the first place...
And... I'd imagine that adding the additional braking stages would add significantly more weight than we'd save by dumping the heat sheild. Oh well, it was a thought.
Then, if it were built, there'd be the touchy subject of trusting people's lives 100% to an engine system for them to return to Earth intact- I wouldn't want to be the engineer responsible for building it. I mean, I guess there's a phase of launch right now that's like that, but that's not to say it's a good idea.
Hey, thanks for humoring my question!
That's pretty harsh. I mean, I get into arguments with her all the time and think she's biased about certain things, but when it comes to aerospace, she's one of the most knowledgeable folks around here.
So what, she's somewhat knowledgeable about aerospace, she's also an incredibly biased liar who has claimed that NASA shuttle missions led to the development of NPH and Lente insulins (and a host of other drugs), which were on the market for decades before NASA ever launched the first shuttle mission. When confronted with demands for proof of the scientific value of the Shuttle and ISS the best she has been able to come up with are popsci articles from news websites and press releases from research organizations that are receving NASA money to conduct research on the Shutttle and ISS. And despite her knowledge about aerospace she has a blind spot when it comes to discussing the disfunctional NASA bureaucracy in the manned space program, or the fact that NASA lied to everyone about what the Shuttle was going to be able to do. Given this lack of integrity on her part why should I respect her expertise?
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Yes, I am aware of Orbital, but organizations have not been realistically considering this configuration for manned flight until now. There has been slideware for decades, true, but no engineered flight hardware since X-15.
Carrier aircraft are highly and easily reusable, thus the return on the investment is much more recoverable than in any vertical RLV.
Take this concept to the next (and higher) level: the hypersonic launch of the 'upper' stage. Such a configuration would extract the maximum advantage of atmosphere (no oxidizer needed in launch vehicle/first stage). Hypersonic vehicle separation seems like a huge problem, however.
Crashes Firefox (Deer Park Alpha 2) also.
what? talking about a xenophobic 70's porn parody is bad?
context people, context.
The Kruger Dunning explains most post on