Rutan: NASA is Dull

Palomar · 2005-05-21 05:22:17

http://www.spacedaily.com/upi/2005/WWN- … html]Click

*He makes some valid points. But with his (immediate, anyway) "space fun" plans, it's still stuck in LEO.

NASA may be dull as hell in some respects (the shuttle especially). But it has some truly fantastic and spectacular science probes "out there" (as we know from all the active threads in the Unmanned Probes folder), which are anything BUT "dull."

There's certainly no harm in having fun alongside of science....just so long as science doesn't get sidelined. Not sure if Rutan cares or not, in that regard.

--Cindy

Fledi · 2005-05-21 05:45:19

If he ultimately makes LEO travel as cheap as the suborbital flights, then you can build manned Mars ships for the price of one of todays probes anyway. Just imagine how cheap probes will become then.

Palomar · 2005-05-21 06:16:12

If he ultimately makes LEO travel as cheap as the suborbital flights, then you can build manned Mars ships for the price of one of todays probes anyway. Just imagine how cheap probes will become then.

*Hi Fledi. I hope so.

Of course Rutan has his own agenda, but it does seem a bit intellectually dishonest that he attempts to portray NASA as completely boring. As human spaceflight goes, it sure is. But as probes and robots go, NASA is rocking the Solar System.

Will be interesting to see how it all unfolds as the years progress. I guess space tourism is inevitable. I simply hope it doesn't impede/thwart science. And also that this doesn't develop into a Fun vs Science issue, but rather that the two can be blended. However, there seems to be little genuine desire or appreciation for science (not referring this to Rutan, but speaking "in general")...which worries me in this regard.

--Cindy

Fledi · 2005-05-21 08:50:55

Well Cindy, spaceflight wasn't driven primarily by science in former times, too. Compared to those motives, fun seems to be quite preferable. I guess science and fun will become blended to some degree, if it is only by having the tourists pay for making better launchers.
But I agree NASA definitely did much in the field of space science, most of todays understanding of the universe around us comes from that. Rutan is propably just fed up with the costs NASA has for manned missions and is giving some way to his disappointment.

Palomar · 2005-05-21 08:56:04

Well Cindy, spaceflight wasn't driven primarily by science in former times, too. Compared to those motives, fun seems to be quite preferable.

*Hi Fledi. Yes, you are right.

And I'd rather have "fun" as a motivator instead of the other looming option (militarization). :-\

--Cindy

GCNRevenger · 2005-05-21 09:30:44

If he ultimately makes LEO travel as cheap as the suborbital flights, then you can build manned Mars ships for the price of one of todays probes anyway. Just imagine how cheap probes will become then.

I will tell you right now that he will fail. Getting into orbit requires hundreds of times the energy as his dinky plastic rubber-rocket plane needed for its suborbital flight. It will -never- be that cheap barring a space elevator.

Fledi · 2005-05-21 09:37:30

Yes if you go to LEO straight from the ground that's true. But I still have much faith into those tether designs, if we can make that work nothing much more advanced than Rutan's craft will be needed.

GCNRevenger · 2005-05-21 13:52:44

Tethers? Nonsense. Besides all the technical hurdles, which I believe are fatal to regular use, is the problem of scaleability: the fact that it isn't. You cannot ever reach a high launch rate since the thing is not in a geostationary orbit, and must take some time to rebuild its lost momentum from every transfer and the substantial drag placed on it, particularly with those huge solar panels or reactor radiators it would need. So, if you can't ever reach much of a launch rate without dozens of them, they will never be economical, even if you could get it to work reliably (which I think will be very hard).

Mad Grad Student · 2005-05-21 15:01:54

I'm all for the further privatization and commercialization of space, but I don't see how attacking NASA will accomplish that. At the core of the subject, NASA and the alt. space companies are both working for the same thing, creating an enduring human presence in the universe outside of Earth (which is where most of the universe just so happens to be). NASA takes this goal and adds to it the objectives of advancing earth and planetary science, astrobiology, and the like. Start-up companies add the goals of opening space up to everyone and making it "fun," so to speak. These missions are concomitant to each other, not contradictory, and the sooner people like Mike Griffin and Burt Rutan realize this the better.

dicktice · 2005-05-21 15:13:20

GCNR: "Dinky plastic rubber-rocket plane" is typical of your slanting an argument. For dinky, I read small, compact and efficient. For plastic, I read composit carbon fibre construction. For rubber-rocket, I read throttleable safe solid fuelled reaction engine. Who cares how Burt Rutan goes about his step-by-step experimental design process--he is out to get results affordably by making each incremental advance pay its own way. Neither I nor you have a clue as to what he and his von Braun-like team will come up with next. You sound like that silly know-it-all who predicted the impossibility of flight, based on pre-Wright Brothers thinking regarding the importance of feathers. Ditto, pre-Goddard thinking regarding the impossibility of throttable burning based upon Congreve rockets. I'd give a lot to sit-in on one of their brainstorm sessions going on just now. No naysayers allowed!

Fledi · 2005-05-22 06:28:17

Calculated for a new 20 ton cargo arriving every 5 days you need about 100 MW of electrical power if you use a 2000s ISP Ion engine to compensate for the lost orbital energy. Should be much better to do that with an electromagnetic tether for you don't need any propellant that way, or maybe even with a solar sail.
So that would be about 1000 tons every year of cargo that stays in orbit. Then there is the other cargo that goes back down, for which you don't need to compensate (it gives back all orbital energy when it's released from the tip at the slowest point).
This could be tourists, 0 g manufactured goods, moon rocks, space junk, etc.
For the drag issue, the solar cells/radiators/sails should be at the center of rotation, which is not lower than 600km above surface at the perigee for a 500km tether. At the apogee, it should be several 100km further out. Drag is not really critical at these altitudes even for large surfaces.

GCNRevenger · 2005-05-22 13:13:00

GCNR: "Dinky plastic rubber-rocket plane" is typical of your slanting an argument. For dinky, I read small, compact and efficient. For plastic, I read composit carbon fibre construction. For rubber-rocket, I read throttleable safe solid fuelled reaction engine. Who cares how Burt Rutan goes about his step-by-step experimental design process--he is out to get results affordably by making each incremental advance pay its own way. Neither I nor you have a clue as to what he and his von Braun-like team will come up with next. You sound like that silly know-it-all who predicted the impossibility of flight, based on pre-Wright Brothers thinking regarding the importance of feathers. Ditto, pre-Goddard thinking regarding the impossibility of throttable burning based upon Congreve rockets. I'd give a lot to sit-in on one of their brainstorm sessions going on just now. No naysayers allowed!

I am not trying to be cruel about belitting Rurtan, but I do indeed mean to belittle his little ship and his plans for an orbital vehicle... To be quite frank, the accomplishment of SpaceShipOne is really no big deal. The old Bell X-2 back in 1956 could have done the same thing, and now it has taken almost fifty years for Burt to con some money out a billionaire to do it? Even some of the faster Russian interceptor jets or the SR-71 flying today could almost match it. I am not impressed.

And the technology and his future plans? You are willfully ignoring the cold, hard truths about the physics and chemistry of spaceflight: there is a very good reason why there are no small and efficent rocket-powerd orbital vehicles, and that is because they are impossible. Why? Simple, thanks to the rocket equation, your vehicle must only be a small fraction of the mass of propellant (physics) and there are no practical dense high-energy propellants (chemistry). There just aren't any.

Why not? As long as we are using the energy bound up in a chemical reaction, which involves the rearrangement of molecular bonds, but the mass of propellant is governed by the nucleus. Since a practical fuel must be stable enough to handle safely, then you can't use an unstable super-fuel to try and cheat. So, if you can't bring a few really powerful molecules, you must instead bring alot of less powerful ones, which idealy have the lightest nucleus you can find... Hydrogen is the therefore the ideal rocket fuel, and Oxygen still the best practical oxidizer. There just isn't going to be a super-fuel to make little rocket planes fly.

Speaking of fuels, you know that rubber rocket nonsense? Those types of engines might be pretty safe and easy to use, but they suffer from one really fatal flaw... poor energy density, that is, they just don't pack enough energy per-pound to make a practical orbital vehicle like Rurtan wants, and have only about half the specific impulse of Hydrogen/Oxygen engines. The size and mass of rubber-rocket you would need is unrealistic for such an RLV: just to push an orbital version of SSO to orbit, it wouldn't fit on a 747 jumbo jet... Getting into orbit requires FAR more energy then suborbital. Period.

Carbon composits are just fine for airplanes in the low mach numbers, and might even be okay for rocket fuel tanks, but they have this nasty habit of melting and burning if they get too hot, unlike Titanium... Such composits just aren't serious contenders for an orbital spacecraft, SpaceShipOne would be a cloud of ash before it ever hit the ground if it were reentering from orbital velocities (Mach 25+), and even with an RCC heat shield the wings would rip right off since they would be too flimsy.

Unless Burt gets it in his head to abandon dropping rocket-powerd Cessnas out from under stretched Leer jets, his dreams of an orbital vehicle are a joke... Also before closing, I want to address this idea of incremental steps twards an orbital vehicle: forget about it, it will never work. Why not? Simple, since you need 100 times the energy (and 100 times the rocket) to get to orbit then suborbital, there are no steps in-between, and so nobody will pay for an intermediate vehicle. Sorry.
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In closing, the reason why the comparison between Rurtan and the Wright Brothers is stupid is really very simple: the Wright Brothers wern't working against the unchangeable minimum mass of the atom, which no matter how much Burt wishes and schemes and brain-storms, he cannot change. Thats just the way things are.

"No naysayers allowed!" ...Ahhh the motto of the AltSpace community. Without the naysayers, and without the AltSpace'ers taking the naysayers seriously, then they are just dreamers who will inevitibly fail, and rightfully so. Without naysaying, they should never be taken seriously, because they obviously aren't being serious about the challenge of spaceflight.

GCNRevenger · 2005-05-22 13:28:18

Calculated for a new 20 ton cargo arriving every 5 days you need about 100 MW of electrical power if you use a 2000s ISP Ion engine to compensate for the lost orbital energy. Should be much better to do that with an electromagnetic tether for you don't need any propellant that way, or maybe even with a solar sail.
So that would be about 1000 tons every year of cargo that stays in orbit. Then there is the other cargo that goes back down, for which you don't need to compensate (it gives back all orbital energy when it's released from the tip at the slowest point).
This could be tourists, 0 g manufactured goods, moon rocks, space junk, etc.
For the drag issue, the solar cells/radiators/sails should be at the center of rotation, which is not lower than 600km above surface at the perigee for a 500km tether. At the apogee, it should be several 100km further out. Drag is not really critical at these altitudes even for large surfaces.

One HUNDRED megawatts? Dream on! NASA is talking about nuclear reactors with only ~100 kilowatts, and "future upgrades" of only 300kWe. And what if the reactors fell out of the sky? And the huge radiators getting pelted by space debries and leaking, melt down would follow quickly.

Likewise, a 100MW solar array would be insane, and easily be kilometers across and would be too fragile to gimbal so that they couldn't produce much energy anyway. Oh and the energy storage, you can't simply shut off a multi-megawatt ion engine whenever you are in shadow, you'd have to store energy to at least idle it, which would be HUGE and prone to breakdown. Solar sails would be even worse, especially in LEO where they would spend so much time in the dark, and would be so huge that even at 600km the drag would be substantial, and might even dip down into the atmosphere.

No way, it'll never happen. And if it is much smaller then this, its worthless. Just as I said, the lack of scaleability dooms the tether idea. Either we build a true honest-to-goodness RLV (Shuttle LSA/Saenger-II, X-30, giant DC-X) or a space elevator, or else we aren't going anywhere fast.

Fledi · 2005-05-22 15:05:33

A one hundred MW solar array would have a surface area of about 1 square kilometer. From a standpoint of mass, it is doable with amorph cells (6 micrometers thick) spanned across a solar sail like grid.
Storing the energy? Nothing easier than that, you have that huge rotating tether anyway, just let a smaller, but still massive tether counter-rotate and draw the energy back from it in the shadow, like from a dynamo.
Haven't done calculations on the drag yet, but have seen drag figures for the ISS with rate of orbital decay slowing down much faster than linear with altitude. But you're right I should have a closer look at that issue, will look at it some time.
For the engine, an electrodynamic tether should be better for the job than an ion engine or sail, haven't done any calculations on that too, but I have the feeling it would also be more energy efficient than the ion drive I proposed.

Simple, thanks to the rocket equation, your vehicle must only be a small fraction of the mass of propellant (physics) and there are no practical dense high-energy propellants (chemistry). There just aren't any.

Aside from a recent crazy idea of mine of using rotating nanotubes placed on a rapidly rotating core cylinder as fuel (if they ever become THAT cheap you would have 800s ISP and more with that one), for the example of powerful chemical reactions there is the energy you would get from rebinding dissoziated molecules (H+ plasma for example), but don't ask me how to densely pack the plasma for this

I'd give a lot to sit-in on one of their brainstorm sessions going on just now.

Yes, me too, this goes also for the other teams' ideas.

Mad Grad Student · 2005-05-22 15:46:37

If Scaled Composites ever does find a way to make orbital spaceflight reasonably cheap, it won't be with anything that resembles spaceshipone, but that doesn't mean it can't be done. Everybody knows by now that hybrid rockets don't have the isp needed to make SSTO spaceflight possible, let alone with a reusable launch vehicle, but there are other systems that can be used. Liquid oxygen and hydrogen aren't exactly the safest chemicals to play around with, but the fuel combination is efficient enough to make SSTO RLVs a possibility. It's all a matter of keeping the craft's empty weight under 15% of its gross weight.

This would not be practical for an air-launched system, and I'm sure that Burt Rutan is able to understand that. To go for orbit any daring alt. spacers will have to instead approach from the ground up, with LOX/LH2 or perhaps methane-fueled rockets. Global flyer already has a mass ratio very close to what a reusable single-stage to orbit launch vehicle would require, raising the possibilty that it could be feasible with today's technology. Granted, a reusable spacecraft will need life-support systems, a TPS, and the like that will all raise the amount of dry mass needed, but it won't need big long wings or control surfaces, further leveling the playing field. Hardly any of Global flyer's empty weight went into its fuel tanks, so its reasonable to think that even alotting for the much larger tanks required to store hydrogen and oxygen, the extra mass required here could roughly be balanced by the mass saved by not having flight surfaces.

"No naysayers allowed!" ...Ahhh the motto of the AltSpace community. Without the naysayers, and without the AltSpace'ers taking the naysayers seriously, then they are just dreamers who will inevitibly fail, and rightfully so. Without naysaying, they should never be taken seriously, because they obviously aren't being serious about the challenge of spaceflight.

This is an excellent point. The alt. spacers need to be questioning themselves constantly as to what they can really do and how to best accomplish their goals. Nobody is ever going to get anywhere by sitting back and accusing all those who oppose them to be nay-sayers, just as nobody is going to get anywhere by sitting around pooh-poohing every iconoclastic idea they come across regardless of its potential merit. Skepticism is critical, but so is ingenuity. What's critical here is that the alt. spacers are able to adress any reasonable doubts about their capabilities. Always question, never defend. That's actually one of Rutan's mottos.

srmeaney · 2005-05-22 17:13:29

One HUNDRED megawatts? Dream on! NASA is talking about nuclear reactors with only ~100 kilowatts, and "future upgrades" of only 300kWe. And what if the reactors fell out of the sky? And the huge radiators getting pelted by space debries and leaking, melt down would follow quickly.

you get big mushroom clouds in the part of the entry elipse that covers texas.
Sane people still have a regular fuel system on the nuclear propulsion system so that sucker can be pushed into the moon and "disposed of".

BWhite · 2005-05-22 18:56:28

If he ultimately makes LEO travel as cheap as the suborbital flights, then you can build manned Mars ships for the price of one of todays probes anyway. Just imagine how cheap probes will become then.
I will tell you right now that he will fail. Getting into orbit requires hundreds of times the energy as his dinky plastic rubber-rocket plane needed for its suborbital flight. It will -never- be that cheap barring a space elevator.

I was at Rutan's talk. In person.

He was VERY candid that SpaceShipOne is an airplane. Not a spaceship. Rutan claims that he was the last person to talk to the pilot before they closed the hatch and he said "Remember, its just an airplane. . ."

That said, t/Space to LEO has NOTHING to do with SS1. [Edit - - this is not really true. It appears the method of engine pressurization is similiar by being at altitude before engine ignition and the whole air-launch idea is the same, but the crew capsule and SS1 are not related, except perhaps at the composites material level]

They had an extensive display at ISDC and I was told by the representatives that the presentation will be on the web later this upcoming week.

t/Space is not really being run by Rutan. Gump is the guy in charge. The plan is for ultra-cheap Earth to LEO with the Crew Exploration Vehicle to be a much larger more capable vehicle that stays in LEO - - parked as it were - - between missions.

The CEV is re-useable and never re-enters Earth atmosphere to land once launched the first time. I had a brief chat with astronaut Jim Voss who is a t/Space employee/consultant about the plan and it seems to make sense.

A full scale t/Space crew transfer vehicle mock-up was on display at ISDC and it is very simple (KISS) - - it exists solely to ferry people from Earth to ISS or a new always on-orbit CEV. It is shaped like the old Corona spy-sat film recovery capsules and cannot do anything except ferry crew to and from LEO.

Rather like the small boats that would carry crew from shore to a sailing vessel anchored out in the deep water.

Edited By BWhite on 1116811397

BWhite · 2005-05-22 19:04:53

http://64.78.33.215/document_library/me … df]t/Space pdf - - its really a simple capsule mounted on a 2 1/2 stage small rocket.

An air launched TSTO with light weight ablative tiles for re-entry. The shape (no wings) allegedly minimizes the thermal extremes compared with space planes. They made a big deal about following the old Corona shape.

By doing nothing except being a bare bones crew ferry it is kept simple and presumably cheap. The more capable CEV would remain forever on-orbit meaning it can be deployed WITHOUT the need for a Earth return capabilty which greatly simplifies CEV design costs.

An intriguing architecture.

= = =

http://64.78.33.215/index.cfm?fuseactio … AA]Another link.

Crew time spent aboard this capsule in intended to be minimal.

On Friday I saw a nifty animated depection of how it launches and that is supposed to be online this coming week.

Don't count Rutan amnd t/Space out. There is some real out of the box thinking going on here.

But it is also "Form follows Function" thinking. t/Space has ONE goal for CVX - - get people to orbit simply safely and cheaply. After that, transfer to an expensive robust and sophisticated CEV for some real exploration work.

t/Space does not claim their crew ferry can do anything except ferry crew which is good as it looks to me like it cannot do anything else except ferry crew.

t/Space has stretched its initial NASA funding -- which the agency expected could only support paper studies -- to include flight tests of several key aspects of the proposed system. One such test series began in May 2005 to validate the simulations developed for the release method to be used by the VLA. Marti Sarigul-Klijn leads this project, described in a paper in the t/Space documents library. A 23% size test article of the CXV and its booster was carried aloft by Scaled Composites' Proteus aircraft from the Mojave Spaceport. It demonstrated that the Trapeze-Lanyard Air Drop (TLAD) method primarily invented by Dr. Sarigul-Klijn performs as predicted. TLAD enables a belly-mounted booster to begin a slow rotation as it drops away from the carrier aircraft. This turns the booster toward the vertical before its first stage begins thrusting. Other systems, such as the Orbital Sciences' Pegasus or the earlier X-15 aircraft, require wings to make this "gamma turn." The TLAD method thus reduces system weight by avoiding the need for wings.
The t/Space release method also enables the capsule and booster to cross the aircraft altitude behind the VLA, rather than in front as is the case with most aircraft-launched boosters and missiles. In the event of an anomaly, rear-crossing trajectories are safer for the carrier aircraft.

Air launch benefits:

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.

Edited By BWhite on 1116811020

el scorcho · 2005-05-22 19:30:52

I'd say everyone here has a healthy respect for the robotic probes and what NASA is doing with them--I spent a Friday night date watching live coverage of the Huygens probe's descent to Titan with my girlfriend. Thankfully, she's very tolerant of my obsession with space. :laugh:

But let's face it: most people outside the space community would much rather watch Desperate Housewives than hear about the sandpit trials of a little rover that could. NASA has basically defined itself by the robotic probes and to most people, that is very dull. John Q. Public could care less about the chemical composition of this or that rock.

Suborbital space tourism on a large scale will lead to breakthroughs in propulsion and vehicle design--and I disagree with the statement that an orbital vehicle will not even resemble SpaceShipOne. Orbit, I believe, is generally agreed to be a height of 400 km--SS1 got to 100 km with N2O and tire rubber. Orbit with SS1-derived technology is probably a lot closer than we think.

dicktice · 2005-05-22 20:18:05

GNCR: You mistook my critique of your "dinky, etc" diatribe, but since everything I would have countered with has already been included in the preceding three posts, I won't bother. Your pessimistic responses are keeping this thread interesting, with counter arguments sufficiently optimistic to maintain it on the "front page," which is great.

GCNRevenger · 2005-05-22 22:26:05

Suborbital space tourism on a large scale will lead to breakthroughs in propulsion and vehicle design--and I disagree with the statement that an orbital vehicle will not even resemble SpaceShipOne. Orbit, I believe, is generally agreed to be a height of 400 km--SS1 got to 100 km with N2O and tire rubber. Orbit with SS1-derived technology is probably a lot closer than we think.

Wrong. Getting into orbit has almost nothing to do with your altitude, getting up that high isn't too hard, the problem is staying up there: in order to enter a stable low-Earth orbit, you have to be moving fast... very fast. Eighteen thousand miles an hour fast, if memory serves. You have to moving perpandicular to the surface so quickly, that you "fall" around the curvature of the Earth, basically flying thousands of kilometers to "get out of the way" of the Earth before you fall and hit the atmosphere. SSO just barely reached that high altitude even with a Mach-3 dash, and had almost zero tangent velocity... Thats why it needs three hundred times the energy.

srmeaney · 2005-05-22 23:16:45

Sure NASA has it going on where Probes are concerned but Burt is looking for something along the lines of Mega fantastic:

Nasa declared the Governing body (independent of even the USA) for all activity on the Moon and mandated with some serious colonisation in the area of a million population backed up with a declared national wealth in the magnitude of 10 million billion based on mineral rights alone.

That is supposed to pay for real advances in passenger to the moon kind of transport and colonization.

That alone would get the kids in school.

Rxke · 2005-05-23 03:07:47

BWhite, the 'another link'...

last picture of Proteus with 23% mockup testflight....

Brilliant, and all that for the price NASA thought would only cover the paperwork, :laugh:

That's Rutan's advantage: he has a whole lot of flexible testplatforms already, Proteus, White Knight, SS1...

They can do quick and dirty testing out new ideas, with a very tight budget. No need to hire an army or NASA carrier, buy a sounding rocket etc...

The Proteus pic proves another point: Rutan is a long-time visionary, Proteus was built with something like that in mind originally, (launching lightweight stuff) but there were no takers, or it proved impractical (proteus probably too light)
But today he can use it as a fantastic test platform, it's all there, the high altitude, the long flight-capability, so they don't have to rush tests...

el scorcho · 2005-05-23 19:38:48

Posted on May 23 2005, 00:26
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Quote (el scorcho @ May 22 2005, 16:30)
Suborbital space tourism on a large scale will lead to breakthroughs in propulsion and vehicle design--and I disagree with the statement that an orbital vehicle will not even resemble SpaceShipOne. Orbit, I believe, is generally agreed to be a height of 400 km--SS1 got to 100 km with N2O and tire rubber. Orbit with SS1-derived technology is probably a lot closer than we think.
Wrong. Getting into orbit has almost nothing to do with your altitude, getting up that high isn't too hard, the problem is staying up there: in order to enter a stable low-Earth orbit, you have to be moving fast... very fast. Eighteen thousand miles an hour fast, if memory serves. You have to moving perpandicular to the surface so quickly, that you "fall" around the curvature of the Earth, basically flying thousands of kilometers to "get out of the way" of the Earth before you fall and hit the atmosphere. SSO just barely reached that high altitude even with a Mach-3 dash, and had almost zero tangent velocity... Thats why it needs three hundred times the energy.

And why is SS1-derived technology incapable of releasing that amount of energy? I never said SS1 was going to orbit; SS1 was developed for suborbital flight. Its successes have laid the foundation for SpaceShipTwo, which will be designed for suborbital flights at slightly higher altitudes than the X-Prize flights. Building on these successes, a future vessel will be built for orbital flight.

GCNRevenger · 2005-05-23 20:01:16

No it won't.

Why not? Easy, the technology that Burt used to build SSO is simply not good enough to build a practical orbital vehicle.

Since the rocket equation dictates that the faster you need to go, the amount of fuel increases geometricly then the amount of fuel Burt would need for his N2O/HTPBD rocket would be insane, the engine would be so big it wouldn't fit on a 747.

Likewise, the heat shield on SSO barely survives Mach 3... how is it going to survive Mach 25?

The flimsy composit contruction that his company deals in primarily is not going to be good enough either, its too fragile and can't take much heat.

...All these things that Burt is good at, none of them are good enough.

I want to reiterate that the difference between an orbital vehicle and a suborbital one is so big, that there is no reason to build a vehicle that only goes half way, and so nobody will pay for one.

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