Correct me if I’m wrong but doesn’t the Pegasus rocket already achieve orbit for satellite launches with the same finess vs. brute force method as SS1?
Yes, it does, but is unmanned, and requires a B-52 to get it aloft…
Also, they have a tendency to blow up.
The announcer on the ground this morning (I went out to watch the launch) said that SS1 was going slightly over Mach 3 when the burn finished.
The tendency to blow up is - ehm - unnerving, but being carried aloft by another plane is the SS1’s modus operandi, too. The Pegasus can only carry about half a metric ton, though, which isn’t a lot for an orbital vehicle.
I’m pretty sure Rutan could build a bigger and better White Knight if that was what it took. (Actually, I’d be seriously surprsed if the crazy bugger didn’t already have a design lined up.) I doubt, however, that he’d go with a winged design for an orbital vehicle - reentry is much easier in a traditional capsule, although if anyone could design a seriously jazzy capsule, it would be Rutan.
Is anybody privately devoloping a scramjet? I know NASA tested a Pegasus hybrid scramjet back in March that hit Mach 7. With current technology, it seems like a scramjet is the best bet for SSTO. You get all that cheap altitude with your wings and don’t need LOX till you run out of air. Once you gety up to scramjet velocity, that is. Seems like chep solid rocket boosters might be good for that.
Oh, and W007!
The projected price that the company set for a ticket to space is 200k, right?
With all the other teams and their own plans they had for winning the x-prize nearing completion won’t there be a bit of competition sometime in the next few years? What is the minimum price that one flight could cost and still be making the company a profit? Or will the price of a trip not drop and end up having a ‘diamond style’ pricing where all the space trip companines could charge something like $200k and never let the price drop?
Ya know… SS1 doesn’t use either heatshields or thermal tiles to re-enter the atmosphere. And it does have the re-entry problem to contend with. Rutan’s system of using atmospheric drag to prevent the speed/heat from building up to lethal levels is quite elegant, and also has the added feature that the spacecraft remains stable because of physics and aerodynamics rather than elaborate devices, sensors, and thrusters. As long as the spacecraft retains its shape and the laws of physics aren’t suddenly repealed it works - very few moving parts to malfunction. It might be most accurate to say that it truly is a gravity-powered re-entry.
The question is - can that technique be scaled up? SS1 is able to do this in part because it doesn’t weigh that much relative to the drag surfaces and there’s a limit to how fast it re-enters the atmosphere. But if this could be scaled up to a larger vessel, and if it could be made to work for orbital re-entry, then you’d have a system that required no heat-shielding (alright, maybe some) to safely return. Which would probably decrease a significant portion of the risks involved in that phase of a spaceflight.
SS1 has the reentry problem, but it not quite. It’s going 1/10 escape velocity, and that’s a lot less forward V to have to bleed off than orbital reentry.
So far, there are 2 methods of slowing down, reactive engines and aerobraking. Reactive engines will probably never happen in an atmosphere as thick as ours, because the fuel cost is prohibitive. Save that for Martian or lunar landing.
Aero braking is what we’re stuck with, until antigrav or transporter beams come around. Rutan’s idea with SS1 is inspired, but will that fliptail hold up to the stress loads of orbital re-entry? I doubt it, as designed. Also, SS1 has the heat load of a current jet fighter, which is something that polished aluminum can handle. Rutan will have to put a lot of $$$ into materials research to figure out a new heat sheld. There has to be a way to do it without the maintenance costs of silica tiles and RCC composites. The shuttle required those because of the heavy lift requirements; SS2, designed to get 2-3 people in orbit on the cheap, can do something a lot simpler.
That’s what I want to watch…
Also, regarding Pegasus: it has to be launched from a B-52 partly for the lifting capacity, but also because they need the hull to fly the support equipment. NASA does not do anything on the simple. SS1 has a low amount of equipment and telemetry, and was flying from a launcher designed hand in hand.
BTW, The X-43 program did a captive flight test last week with Pegasus, which was successful. There will be an attempt at a Mach 10 flight very soon.
How cool - Google has a tribute banner for the event.
There may be another way to get down from orbit - and up into orbit. I mentioned it in a GD thread, but JP aerospace is working on a plan to fly a balloon into orbit. It actually looks feasible. They take a smaller ballon called the ‘ascender’ (which is currently under construction) to 140,000 ft to a permanently stationed inflatable platform. There, they construct a mile-long ultra-low density balloon which has electric engines (ion thrust, maybe. I’m not sure). Anyway, that big balloon gently lifts off from the station and accelerates over a period of days to orbital velocity, using both bouyant lift and aerodynamic lift in the hyper-thin atmosphere to keep it aloft and climbing while it accelerates to orbital velocity.
To come down, it reverses the process. It brakes very, very slowly, gradually entering the atmosphere and controlling its deceleration so that heat doesn’t build up. The ride to orbit takes days, and the ride back takes days. It docks at the 140,000 foot station, and an ascender takes the crew back to the ground. It’s a very cool concept and might actually be possible.
As for Rutan’s design - if anyone can come up with a cheap way to orbit, Rutan can. But don’t underestimate the difficulty. It takes about half the energy to get to orbit as it takes to get *anywhere. And remember, if you need ten times the energy to get to orbit than SS1 has, that doesn’t just imply ten times more fuel, because the fuel itself requires energy to haul. So you need more like 100 times the fuel. That’s why a Saturn V rocket starts out a giant monstrosity, and by the time the last bit is on the way to the moon it’s the size of a truck. Most of the fuel in a Saturn V is required to lift the weight of the fuel required go get a very small payload going very fast. There’s a law of diminishing returns that you hit very quickly.
There are no easy ways around this, short of inventing a miracle fuel. Dropping from a mothership helps a lot, because a lot of the fuel of a rocket is used just to get it to the altitude something like SS1 starts from. But dropping from a mothership limits the size of your ship, and you still need a hell of a lot of fuel.
There’s just no getting around the laws of physics. Rutan can cut the costs of support, of systems, and engineer out the bad designs of a space shuttle. Maybe he can come up with some new materials that make up a cheaper heat shield, and some novel aerodynamics to make atmospheric entry self-stabilizing. But he can’t get around the fact that to get to orbit with a rocket you need a stupendous amount of fuel for each pound of payload.
According to the Discovery Channel documentary “Black Sky” that aired Sunday night, they are mostly the same, but bigger designs.
He explained that this is “tier 1” of his greater plan. Tier 2 is orbit, tier 3 is extra-orbital(i/e other planets). The designs he showed on paper looked like the current craft, only bigger. He showed a drawing of a white knight with the wingspan of a 747(guessing from scales, etc), and the picture he showed is close to the current craft, except for the scale.
SS1 looked the same except for a large cylindrical backend, that roughly triples the length of the craft. Basically it looked like he attached a boostser rocket to it. He also has it carrying 7 people not 3.
Did anyone else watch that documentary? Man are they out there on the edge. They have never had a clean flight, but yet they go forward. I hope they don’t have an accident, but if they continue to fly SS1 as it is, I think it’s inevitable, that thing looks fragile and most components are not well tested. Rutan mentioned the risks several times, so he is aware of it
One last cool thing from the documentary, apparently talks are in the works to use Rutans launch system to send a privately funded probe to Pluto. I’ve got dibs on the first planetary RV, so I can take a cruise around the solar system.
Google banners: the new status symbol. 
The Discovery channel documentary showed events leading up to the X-Prize. To see the actual two X-Prize launches, there will be another show on Thursday.
“Cheap”, of course, being a relative term here.
I think Rutan is smart enough to understand the problem… but a lot of folks poo-pooing his accomplishment don’t. It will take at least as much time and effort to get to orbit as it did to get to sub-orbital space, and more money and material for sure.
I’d venture to say that’s the first principal of rocket science - diminishing returns.
Well, heck, they move the Shuttle around on the back of a 747. What’s the biggest, highest-altitude mothership that’s practical to build? They admit they did White Knight on the cheap (again, “relative cheap”). THAT concept certainly could be scaled up (would probably wind up a somewhat different shape). And the higher you can get the mothership to go the less rocket fuel you need to launch a given mass into orbit. I don’t think the launch system of the SS1 is optimized yet… you could launch something heavier, higher, and faster. How much heavier, higher, and faster is the question. I don’t have the knowledge base to answer that. But remember, SS1 was designed specifically to win the X-prize. If the parameters of the contest had been different, so would SS1.
Regardless of what you’re building, I’d say self-stablizing re-entry alone is a great concept and I wouldn’t be surprised to see it utlized in the future by people other than Rutan - I’m thinking we might not have lost some of the Mars probes if that sort of system had been used. There’s a lot to be said for engineering-out problems, inventing new guidance systems, and reducing the need/cost of support infrastructure. Even if future spacecraft don’t resemble SS1 I think some of the technology and concepts could be utlized to bring down current costs.
If Rutan does have something new up his sleeve, he won’t show it until he’s ready. Just because he has a drawing of a 747 White Knight doesn’t mean that’s what he’ll use to launch to orbit. He might… but he might not. The man keeps his mouth shut until he’s ready to do the deed. I’m sure he’s got a box full of ideas for really neat stuff he’s discarded because he found out it wouldn’t work or came up with a different solution to the problem. We’ll never see what’s in that box, it’ll stay in the back of his closet (so to speak) until he’s no longer around.
Yep.
Yep. Just a bunch of crazy homebuilders out in the desert breaking records.
I’m sure they’re thinking the same thing - only more so.
Rutan has a good safety record. He may be “out on the edge” but he’s cautious about how fast and far he and his people push the envelope. However, if you’re going to be an aviation pioneer there are unavoidable risks.
Everything Rutan builds looks fragile. And a lot of it flexes in a way folks accustomed to more rigid wings find disturbing. That doesn’t mean it IS fragile, at least in the sense of easily broken. He also seems pretty good at building in some safety margin.
The Voyager, for instance, actually lost wingtips on both sides at take-off on its world-circling flight, and continued to lose bits off the ends of the wings throughout the next nine days of flight, yet still completed the trip and landed safely. Yeah, that was a risk - but it’s also a sign of an airplane that wasn’t as “on the edge” as it might have appeared to be. Likewise, SS1 test flights had some problems, some potentially quite serious, but the systems were, as Rutan put it “robust” enough to allow a safe recovery of control.
Voyager was “single-purpose” airplane. By the time they donated it to the Smithsonian it was no longer airworthy - it was essentially used up and worn out. Didn’t matter - it completed the task it was designed and built for. Likewise, SS1 is a single-purpose machine. I don’t expect to see it fly again, it’s purpose is done. I expect Rutan will go on to build something better, utilizing the lessons learned from this machine.
My point was that it achieved orbit with the same method as SS1. As for a B-52 (or L-1011) that is a matter of scale. To your third point… do you want to live forever?
They can only ferry the empty shuttle, not the solid rocket boosters, the external fuel tank or any cargo. Which isn’t to say a 747 wouldn’t make an excellent launch plane for a smaller spacecraft but the existing shuttle orbiter cannot be launched on one.
Can’t please everyone. As my father is fond of saying, “some people would bitch if you hanged them with a new rope.” I’d rather concentrate on what SS1 did accomplish rather than what it didn’t. Rutan may have stood on the shoulders of giants but so did Newton.
Pegasus was developed as an ASAT platform, primarily. That’s why it has a small capacity; a warhead to take out a satellite isn’t heavy in the great scheme of things. Also, if the end mission is to blow up, then you don’t need to be as careful building it as something cargo or man rated.
NASA’s been burned by Pegasus before, on a failed X-43 flight. I know the scramjet guys would have liked a more reliable launch platform, but one isn’t available that fits the X-43 launch requirements. All it has to do is accelerate the X-43 to the point that the scramjet will light.
As an aside, Pegasus is pure solid fuel, which is a bad when combined with manned flight vehicles. It’s a sore point to this day with the Shuttle. SS1 uses solid rubber as fuel, but carries LOX as the oxidizer, allowing for control.
Now that there’s an incentive, something will come along to do the job better than Pegasus. I hope that Rutan getting the prize doesn’t stop the work his competitors were doing.
Correction - it uses nitrous oxide, not liquid oxygen.
Yup. Even I can be wrong, or I’d be perfect. 
Nitrous oxide is a lot easier to handle than LOX, so this is a better solution. Once again, Rutan is Rutan.
The Discovery Channel is re-running their shows tonight on Space Ship One:
8 pm Black Sky: The Race For Space Part 1
9 pm Black Sky: The Race For Space Part 2
10 pm Black Sky: Winning the X-Prize
Then they’re re-running Parts 1 and 2 at 11 pm and midnight. (all times EST, don’t know about where the rest of you are :))