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#101 2005-03-18 17:41:08

Admiral_Ritt
Member
From: Imperial Capital of the Pacifi
Registered: 2005-03-09
Posts: 64

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

I read that a large part of the fuel mass Is used to accelerate a rocket from 0 to 400 Mph.  In other words the energy required to overcome the inertia of afully fueled rocket standing is a Huge unavoidable Cost.

Only this is an avoidable cost If you Gain Inertia before
your engines fire.  Would if not be better to launch a rocket
DOWNWARD for part of it's lauch sequence.  This was
what Von Braun had theorized would be the easiest way
launch big payloads.  We would call it horizontal sled launching. The  ship would be on a ramp sloping downward at first and then at sloping to a 45 degree angle, at lauch.

If you could find a 5 mile wide mini-valley and lay a launch rail
on it you could try Von Braun's Scheme.  As a bonus you
could attach SRB's to the Sled to attain more velocity
and thus use Smaller Engines/Fuel tanks for your main engines.

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#102 2005-03-18 23:54:47

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

Ummm... but then you would have to spend rocket fuel to "pull up" and change the direction of the thousands of pounds of rocket fuel and payload to from "down" to "up" in a very, very short time/distance span.

Rail launch is a cute idea on paper, but it doesn't change anything really. The cost of building the railgun would be so high that it would probobly aproach the same cost as a reuseable first stage...

So, nothing is changed.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#103 2005-03-19 17:32:30

Admiral_Ritt
Member
From: Imperial Capital of the Pacifi
Registered: 2005-03-09
Posts: 64

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

No offense GNC.   But having  a fully configured LAUNCH
vehicle equivalent to the shuttle's full thrust, moving at 500mph just before ignition is an advantage.

If we had access to a more equatorial, modestly mountainous,
sea facing teritory I suspect we would be launching that way

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#104 2005-03-19 17:37:59

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

No, no we won't. Building the rail big enough to launch a vehicle with a sizeable payload will be very very expensive, and since you will be at a low altitude in the thick air at the end of the rail, moving at a pretty slow speed (500mph out of 17,500mph of orbital velocity isn't saying much) that it wouldn't help that much.

Its still all about the energy. The small amount you add with the railgun instead of a rocket simply isn't that signifigant.

Building a railgun big enough for large payloads (>5m and >20MT) would be out of the question.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#105 2005-03-19 18:03:10

dicktice
Member
From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

I've had to face up to the futility of this idea for the reasons GCNR, and others, have explained--on Earth. But, launching up the slope of Olympus Mons to low LMO (low-Mars orbit) should be possible, I imagine, without even staging your rocket.

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#106 2005-03-19 18:25:36

Soyuz
Member
Registered: 2004-06-22
Posts: 19

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

I just listened to a presentation from a Scaled Compostes employee; he says that while Burt Rutan is dreaming about orbital spaceflight, he has no solution to the problem, and he is not in the running for the Bigelow prize.

Thanks for the info. What was the presentation about? Did he say how far along they where with their ships for Virgin Galactic?

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#107 2005-03-19 18:25:56

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

On Mars you would have a much easier time of it, yes, and you might be able to build up nontrivial speeds. With the air being 200 times thinner (average over altitude) then Earth, and the length of the rail up the gentle slope of Olympus with less gravity, yeah you could build up some serious speed if the rail were built carefully.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#108 2005-03-19 21:21:08

Mad Grad Student
Member
From: Phoenix, Arizona, North Americ
Registered: 2003-11-09
Posts: 498
Website

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

Hmm. The DC-X argument is rather compelling. Maybe it's not possible to build a "perfect" SSTO for under several billion dollars. But there are other elements to consider.

The Falcon I first stage could very nearly be an SSTO as it is. IIRC its empty weight is 6% of its gross takeoff weight which is just -this- close to allowing SSTO flight for a kerosene/LOX launch vehicle. Assuming the tank were stretched and the fuel replaced with liquid hydrogen or methane it's reasonable to think that such a stage could lauch a reasonable amount of payload as a percentage of its GTOW.

Now, the Falcon I has cost roughly $50 million to design and build, and it ought to be flying any day now. The Falcon V uses almost exactly the same engines (slightly uprated thrust versions), so the cost for engine development for a Falcon V-class SSTO would be very low. Musk claims that Merlin engines have demonstrated excellent reusability in tests, though now I suppose we just have to take his word for it. The Falcon V's tank is bigger than that of the Falcon I, yes, but ultimately it has just about the same level of complexity. Pretty much all of the subsystems will likely be common technology between the launch vehicles.In other words, the Falcon V will probably cost just about the same as the Falcon I to develop, ~$50 million, or $75 million with a healthy cost margin thrown in.

It's reasonable to think that for $75 million a small alt. space company with healthy investment can create a semi-kinda-reusable launch vehicle with a payload capacity of 20,000 lbs to LEO and man-rating for a small amount of extra development. That's certainly a start. For $75 million a vehicle capable of launching up to 20,000 pounds and crew capsules for about $1,000 per pound can be developed. That won't set the world on fire but it will definately rock the aerospace industry.

Of course, this has little to do with SSTO development, but bear with me. The development program for the Merlin has cost somewhere in the range of $25 million likely, at most. An equvalent engine that burns LOX/LH2 with super-ultra-great reusability might cost, what, four times as much? Sure, a hydrogen-burning enigne has a much higher isp than a kerosene-burning version, but would the former be much more complex. I'm not quite sure myself, but I would be skeptical of any claims that higher-quality fuels entail an enormous cost increase in development. Then again, I usually try to be skeptical about everything.

That reusability component is the devil in the details, though. How reusable would a "hydrogen merlin" be? How reusable are they to start with? How much resuability is necessary? There are so many variables it is impossible to come up with a highly accurate prediction of what such an engine's cost would be, and even if we knew the factors it'd still be quite tricky. To my educated layman's eye $300 million seems to be a reasonable amount for the development of a decent SSTO-worthy main engine. And so this is how I came to the conclusion that it might be possible to develop an SSTO-quality engine for $300 million, not $3 billion. Just a possibility. Apparently.

Other components for our SSTO will probably cost just about the same as what they cost for the Falcon V, so let's appropriate $50 million for that. The crew capsule part will be another tricky part for development, but how tricky exactly? Assuming your formula that cost increases with the square of complexity and a Falcon I costs $50 million to develop, according to the asertion that it will cost about $2 billion for the crew capsule requires the capsule to be six and a half times as complex as a small semi-reusable launch vehicle. It will be complicated, but six and a half times as complicated as a top-of-the-line sattelite launching machine? That does not seem reasable to me. I see no reason why it will cost more than $300 million for the capsule.

This still leaves the heat shield and landing gear. Everybody hates the shuttle's TPS, but is it really that bad? On an RLV SSTO one would not have to worry about debris from an external tank puncturing it or tiles breaking off due to vibrations from SRBs, vastly reducing the danger of the system. Granted, the maintainance times are absolutely atrocious, but if you really streamlined the operation and tailored it to lean operating costs rather than keeping NASA technicians gainfully employed the turn-around times could be vastly reduced. Enough for "real" RLV SSTO operations? Who knows. It's another variable. In any case, let's include another $200 million for this system.

Finally, for the landing gear. Why not just use a parachute? Assuming the vehicle has an empty weight in the 50,000-70,000 pound range parachutes might still be used effectively. In places like the Bonneville Salt Flats there's nothing but huge swaths of utterly flat land for miles and miles and miles, perfect for landing a giant parachute-landed rocket. Some rather pedestrian shock-absorbers at the bottom of the vehicle would be quite enough for absorbing the impact, and the whole system of parachutes, shocks, and gear would weigh in as a very small portion of the vehicle's empty weight. After landing the crew inspects the tiles, repacks the parachutes, examines the equipment to ensure that everything is cherry, and you're off again. A turn-around time of one week or perhaps less is plausible. That could be reduced to less than a day with a new, better TPS.

What I am saying is that it is possible, just possible, to design, build, and fly an RLV SSTO for about $800 million assuming that previous semi-reusable vehicle infrastructure is already in place. This would be a DC-X style rocket with a GTOW of 600,000 pounds, six hydrogen/oxygen engines in the Merlin class, an empty weight of 60,000 pounds, and a payload capacity to LEO of 8,000-10,000 pounds. Certainly not in the Proton-class, and really flirting with the edge of shuttle-intensive ground ops, but this is do-able. And moreover, assuming that our company merely builds the vehicles and can find four customers a year who will pay a price tag of $200 million, a bargain-basement price $75 million less than an A380, such a rocket would be an enormous profit generator. Those profits could be fed into the next generation of bigger, badder, better SSTOs. If one works progressively, this should be possible, for much less than you might think at first glance.


A mind is like a parachute- it works best when open.

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#109 2005-03-20 11:30:52

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

The end-model finished product DC-I "Delta Clipper" rocket would have stood 40 meters high and 12 meters around at the base, which is almost as tall and wider around then the Shuttle ET for comparison. Virtually the entire vehicle would have had to have been built from composit materials, practically everything would have had to used the lightest available materials... no low-cost SpaceX aluminum here... It was to have been propelled by large radial aerospike ("plug nozzle") engines, which would have given it a major performance edge during the early phase of acent (and make reentry easier with no nozzle sticking out). No engine of its kind of the required size, performance, or reliability has ever been built before... I still don't think you appreciate just what you are up against.

...and all of that trouble for a measly 20,000-25,000lbs payload. And it would have difficulty reaching this mark. SSTO is HARD, very hard. There is no simple, cheap, easy way to do it. It simply can't be done.

"Of course, this has little to do with SSTO development, but bear with me." ...Your right, it has nothing to do with SSTO RLVs, they are one or two orders of magnetude beyond Elon's whimpy toys. Even the avionics would be tens of times more complex.
---------------------------------------------------------------------

Making a liquid hydrogen rocket is much harder then you give credit I think. First off, let me tell you just what a monster this stuff is... it has a density a mere 0.07g/cm3, which is about ten times the volume by mass as kerosene. Its temperature is -273C, which will cause almost any common material to become extremely brittle. It also has the nasty habit of permiating into the crystal latice of metals, and causing them to shatter. This is not a "higher quality fuel," this is an entirely different kind of fuels then kerosene: absolutely it would demand much more complexity. Even the DC-I would have possibly needed slushed hydrogen fuel, that nobody has ever made any rocket for.

Simply stretching Elon's rocket a little won't give you enough volume, you would need more. The tanks themselves would also have to be heavily insulated, since you can't take off if your rocket is coated with tens of thousands of pounds of ice. The viscosity properties are also different from kerosene I bet.

You can't use just copy a bell nozzle engine either; in order to make the engine efficent enough to carry the whole mass of the ship and have some left over, it demands the use of a radial aerospike engine. Linear aerospike engines aren't efficent enough so you can't copy the X-33 engine. Nobody has ever made one before close to the size needed, so there wouldn't be anything to copy. The Shuttle SSME engines cost easily over a billion dollars to develop, and the upgrades to make them almost safe enough to risk bimonthly flights easily another few billions.

Every engine must be able to fire hundreds of times a year (across the whole fleet, 8-16 per flight) without failing or you'll never afford all the repairs, or even lose the whole vehicle (or worse). Nobody to this day has made any operational liquid fueled rocket engine reliable enough (maybe the X-33 engine, but it was't good enough), you can't even count on the SSME not to fail that often. So YES, it does have to be mega-super-reliable. Adding man-rating safety hardware...

"...with super-ultra-great reusability might cost, what, four times as much?" Try tens times. Maybe a hundred times, very easily for a brand-net next-generation super-engine.
---------------------------------------------------------------------

"Everybody hates the shuttle's TPS, but is it really that bad? Granted, the maintainance times are absolutely atrocious, but if you really streamlined the operation... the turn-around times could be vastly reduced."

Are you crazy? You want to use WHAT? YES is it that bad, that since your rocket will be a large low-density composit balloon and not a thick metal space shuttle, losing a few tiles isn't an option, burn-through would be a big problem. A metal heat shield is probobly required.

AndI think that you are deluding yourself if you think that trying really hard to make it easy to service thousands of little glass bricks by hand that you would destroy if your hard-hat accidently hit them (or even if it rains on the them, much less space debries) will magically make it cheap. NASA spends tens of millions of dollars doing this for Shuttle, you are insane if you think that this cost could be radically slashed by "streamlining." Again, AltSpace infaturation and "anti-big aerospace" dogma clouds your clarity.
---------------------------------------------------------------------

"Finally, for the landing gear. Why not just use a parachute?... shock-absorbers at the bottom of the vehicle would be quite enough for absorbing the impact."

Give me a minute to wipe the tears from my eyes... The main reason that parachutes aren't good enough is because they lack sufficent reliability. In order to have enough margin of safety, these would have to be able to fly daily just about... Shock absorbers able to withstand the impact of a 100,000lbs rocket will be anything but light weight either, and how will they deploy around the heat shield or the aerospike nozzles?

Powerd landing with retractable landing gear is the only really viable option, because the whole point of making an RLV requires that it be much cheaper to turn around then it does to build an expendable. Trying to pick up a small office building sized space ship off these salt flats miles from nowhere just isn't practical. The thing has to return directly to the launch site.

You are also trying very hard to ignore the fact that processing the vehicle between flights must absolutely be kept to a minimum. No TPS refurbishing, no breaking down the engines, no parachute repacking, no towing out of the desert, none of these. Even if it were possible to turn around inside of a week, the cost of doing so would probobly must be very low when you compound the development & construction costs.
---------------------------------------------------------------------

I also want to add that the DC-I would be much harder because it doesn't fly like a regular rocket does. It must deorbit and return nose first like a lift body, and then do something really scarry... then it has to perform a 180deg flip while still traveling at high velocity in the thick atmosphere. Just getting this right would require millions and millions of development dollars. And then it has to restart its engines and soft-land upright within meters of target with limited fuel.

You keep on saying "Its another variable, we don't know" but I think you are trying to wish away (oooh, but you don't KNOW that quantum hyperspace drive will be expensive!) the fact that we DO know that these things will be very expensive because they are technologically advanced. You are just trying to ignore reality...

...What I am saying is that you are a AltSpace-crazed quack that real aerospace professionals will never take seriously (nor should they) if you believe in this dreamer nonsense... a hydrogen SSTO with brand new engines RLV for $800M? A joke, not a possibility. Kistler can't even get their TSTO kerosene rocket with antique engines to fly for that kind of money.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#110 2005-03-20 15:39:58

dicktice
Member
From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

I read somewhere on the Internet that "Buran" had a better tile installation (i.e: fewer failed upon landing? size and/or shape rationality? more impervious to heat?) than the Space Shuttle. I'd sure like to know if anyone here has investigated this. Meanwhile, I'll try to do so on my own, and report is true.

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#111 2005-03-20 16:25:25

Mad Grad Student
Member
From: Phoenix, Arizona, North Americ
Registered: 2003-11-09
Posts: 498
Website

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

...What I am saying is that you are a AltSpace-crazed quack that real aerospace professionals will never take seriously (nor should they) if you believe in this dreamer nonsense... a hydrogen SSTO with brand new engines RLV for $800M? A joke, not a possibility. Kistler can't even get their TSTO kerosene rocket with antique engines to fly for that kind of money.

Even assuming that I am a crazy alt.space-hugging quack who has a tenuous-at-best grasp on reality, it would seem that I come out ahead here. You claim that I resort to wishful thinking and falacies to back up my points. You on the other hand resort to insults and name calling. I have absolutely ZERO respect for you as an opponent in this debate now, GCN. If your side of the argument is so obviously correct to every single person who was not born yesterday and lives on this planet, you ought to be able to defend yourself without name-calling. This isn't the playground, we're adults here. If you want to insult people do that somewhere else.

Yes yes yes, we're all very aware that hydrogen is much less dense than kerosene. But much smaller quantities are needed to reach a given delta-V as well. Tank stretching is necessary, but not a vehicle-killing amount. The Atlas first stage was capable of reaching orbit in a single stage after dumping two of its engines, and that burned kerosene. With hydrogen and oxygen no advance over current technology is needed for SSTO flight.

Better insulation will be required as well, but this is not a killer either. Insulation technology is highly mature and remember that an RLV SSTO will only need to carry its load of hydrogen for a couple of minutes. If the hydrogen is pumped into the launch vehicle about ten minutes or so before launch that makes it very difficult for the hydrogen to boil off and minimizes ice formation.

An engine that burns hydrogen will require higher-strength materials to cope with the much hotter exhaust temperatures. How is that grounds for a tenfold increase in development cost? We like to think that these analyses can tell us exactly how much a given increase in reusability and reliability will increase the cost of development, but they can only go so far. No one has ever built an engine of sufficient resusability for an RLV SSTO and because of this there is no example to cite costs from. Any estimates of the cost of such rocket development are educated guesses at best.

Let's pause for a moment and think about the TPS subject. Imagine this. At the bottom of the vehicle a plate of beryllium-copper alloy is placed with holes cut into it just the right size for the engine bells. To cover the engines during re-entry retractable doors made of the alloy lock into place. In between the plate and the base of the fuel tank (or crew capsule) is an empty space filled with vacuum. Since the doors will be open during the whole ride to orbit, creating a vacuum in this space is as simple as letting all the air leak out during launch and sealing it up tight while in orbit. The beryllium-copper will be able to survive reentry temperatures (its the stuff that usually causes damage when sattelites de-orbit) and the vacuum space would insulate the rest of the vehicle. Has anyone considered this possbility for a TPS? Perhaps it could work. The point is that there is no fundamental law of nature that dictates that a heat shield must be expensive and incovenient.

If it were possible to launch from the same desert the SSTO lands in that would eliminate the transport problem. Edwards comes to mind as a place this might be possible, but I doubt the FAA would be very keen on launching away from the coast. What about using parafoils? Parafoils would allow the vehicle to land on a runway like an airplane, in Florida right next to the launch site as well. Of course, no one's ever demonstrated a parafoil big enough for the job yet, but it is another possibility to consider. The landing gear issue is a tricky one to solve, but that is no reason to assume that it will automatically cost a mystical $6 billion to develop the rest of the vehicle.

Being closed-minded never got anyone anywhere.


A mind is like a parachute- it works best when open.

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#112 2005-03-20 19:04:42

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

*sigh* Yes you are correct, I am getting much too emotional about this. I appolgize for being so abrasive MGS, I offer no excuses for my unacceptable behavior.

I see you are shooting more for a Hydrogen powerd KH-1 and not so much a DC-I, so I have been somewhat unfair in my apraisel of your choice of technologies and cost estimates as well.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#113 2005-03-20 21:07:54

dicktice
Member
From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

I'm following these posts avidly. Nice to be on the sidelines, for once. Vital to be able to debate this subject of getting off the Earth at this time, when the participants are weaning themselves from ballistic weapons only, sub-orbital launches. This is why I'm so supportive of Burt Rutan & company, because he's such a rarity, and deserves our support. Get my drift, GCNR?

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#114 2005-03-21 06:38:36

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,017

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

If I do recall correctly last year the air force did some testing of an aerospike solid propellant engine. Though I am not in the know of its specific performance versus a similar sized regular nozzled engine of the same type of propellant.

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#115 2005-03-21 16:56:54

Mad Grad Student
Member
From: Phoenix, Arizona, North Americ
Registered: 2003-11-09
Posts: 498
Website

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

Perhaps my thinking for coming up with a sub-$1 billion figure for RLV SSTO development is somewhat flawed, but I'll try to explain it as best I can. From what I've learned it appears that single-stage to orbit flight is not actually that difficult to do, but making the launch vehicle reusable is extremely difficult. The reason is that current aerospace technology is good enough to allow a kerosene/LOX launch vehicle to have an empty weight about 6% of its GTOW (I prefer using percentages over mass ratios, but that's just me), almost good enough for SSTO flight, and a hydrogen/LOX LV to have an empty weight around 8-10% of its GTOW, good enough right off the bat to be an SSTO.

However, there's quite a difference between and expendable launch vehicle and a reusable one. Naturally expendables don't have to deal with heat shields, landing gear, or airframes sturdy enough to withstand many flight cycles. This is where the subject becomes sticky, because we know that the tanks, engines, guidance systems, and pressurization systems can be made light enough, but we don't know if the other systems such as the TPS and land gear can be for SSTO flight. Powered landing systems require a substantial amount of fuel to be carried, I'm not sure that RLV SSTO designers using only today's technology could get away with that amount of dead mass. Parachutes might be lighter but are a great inconvienance to use if the vehicle is to be reused. I'm a fan of using lifting body airframes, as they require no fuel on landing, can land at conventional airports, and might only add a small amount of mass to the total vehicle. It remains to be seen, however, if any of these approaches can work without an advance in current technology.

My thinking was that, assuming that no advance over current technology is required, it should cost perhaps $800 million or so to develop an RLV SSTO. That would require using mostly technology from a current or near-future LV such as the Falcon V. Modify it to run on hydrogen, make the engines super-reusable, and solve the TPS/landing gear problem and it could work. I don't doubt that a clean-sheet approach a la the DC-Y would cost around $6 billion, but I'm talking about using mostly recycled technology. It all hinges around whether or not that pesky TPS/landing gear situation can be resolved.

Moreover, there really is a difference in the cost efficiency of private industry versus government contracts. The Falcon I and all applicable infrastructure development was created for about $50 million (if only it would actually fly...). The DC-X was created for just about $60 million. Overall the difficulty of designing the two vehicles might have been just about the same. This would mean that Spacex (alt. space) came in at being 16.7% more efficient than McDonnell Douglas (big three aerospace). That alone isn't too impressive, but the difference in practicality of these two ventures is staggering. The DC-X was a prototype technology demonstrator, the Falcon I is a low-cost semi-reusable launch vehicle. Spacex was able to create the Falcon I for this price because it wasn't afraid to simply recycle old technology when it was effective enough for the job. This is how a low-cost RLV SSTO will have to be built if it is done.

In the end, the only way either side will be proven right is if it's actually done.


A mind is like a parachute- it works best when open.

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#116 2005-03-21 19:09:07

dicktice
Member
From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

Very astute of you. That's exactly how things that haven't been done yet, get to be done. Steamboats across the oceans. Submarines beneath the ice. Commercial airships when airplanes were mere toys. Automobiles before there were roads. Bicycles, even, with spoked wheels and sprocket chains, in place of servants pushing you along. Giant steps, all, for their times. Now, vertical reentry from the vacuum of space, interchangeably transitioning from thrusters to airbrake to wing-lift (like flying fishes in the air), another giant step. The next giant step need not be to orbit, but only sub-orbit, breaking longer and longer flight time and distance records. LEO, then will be attainable as just another step, and once done privately, only military constrants can hold us back.

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#117 2005-03-24 11:32:52

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,017

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

Well when the prize for the latest volvo contest winner actually does get to go on his ride then the alternative space providers must continue to the next step and get to orbit IMO.

[url=http://www.denverpost.com/Stories/0,1413,36~33~2779059,00.html] Rocket man

A Northglenn resident will brave the perils of space after winning a flight on billionaire Richard Branson's space-tourism service.[/url]

m24spaceguy.jpg

Does this guy have anymore of the right stuff than those that visit newmars if this were more than a suborbital flight?
I Think we would all like to take his place even on this suborbital ride but we all really are wishing for real space flight I think and of colonization visiting the planets and such.

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#118 2005-03-24 15:48:31

Mad Grad Student
Member
From: Phoenix, Arizona, North Americ
Registered: 2003-11-09
Posts: 498
Website

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

The problem with trying to scale up from entry-level suborbital travel to orbital flight is that there is very little of practical commercial value in between the two ventures. Mach 4 suborbital flight is great for tourism, and mach 25 orbital flight is good for launching satteltites, orbital tourism, maintaining space stations, colonization, etc. If a good, viable market can be found in between the two delta-V extremes, it will be much easier to scale from suborbital as is being done right now by Scaled Composites to real low-cost orbital.

A good next step after SpaceShipTwo-class vehicles might be two-stage semi-reusable launch vehicles. The first stage, probably a spaceplane like Black Colt or the X-34, achieves a delta-V of around mach 15 at 100 miles, where it releases an upper-stage that gives the payload the rest of the kick it needs to reach orbit. That's nearly two-thirds of orbital velocity, and around one-fourth to one-third of orbital energy. Another possibility for such a vehicle would be rapid point-to-point travel for military or airline applications. There's actually probably a good amount of marketability to a Mach 15-capable rocketplane, so this might be a good next step for the alt space industry.

From there it will be much easier to develop the technology needed for orbital travel. That is, much of the technology could be reused from the previous vehicle for the new orbital version. This is another possibility for the alt space industry to consider.


A mind is like a parachute- it works best when open.

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#119 2005-03-25 09:43:25

dicktice
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From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

I stand by my opinion that your "good. viable market ... between the two delta-V extremes" is record breaking flights by wealthy adventurers who, in the absence of off-planet capability, will do whatever hasn't been done yet in present circumstances. Like the recent balloon and airplane circum-navigations. It's in their genes, so to speak, to be first, fastest, longest (Lindbergh-type bravery) ... not richest, powerful-est, backward-est (bin Laden-type cowardice).

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#120 2005-03-25 12:02:39

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,017

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

I was just reading an article related to the shuttle srb's and Asbestos. Where a test 1/6th scale model was just test fired.
Where they are looking for other materials to sub for the asbestos.

[url=http://www.al.com/news/huntsvilletimes/index.ssf?/base/news/1111745757109480.xml] Solid Rocket Test
Marshall booster rumbles, smokes
Engineers work with model to improve reusable shuttle part [/url]

Engineers let the one-sixth scale version of the reusable motor rumble on a Marshall test stand for 28 seconds.

The test rocket emitted about 100,000 pounds of thrust, said Jeff Hamilton, a Marshall engineer who worked on the test, and generated heat of more than 5,600 degrees.

Even at 100,000 pounds of thrust, the motor was still more powerful than the first Mercury-Redstone launch on May 5, 1961, which lifted NASA's first astronaut - Alan B. Shepard - into space. That modified Redstone missile produced about 78,000 pounds of thrust to put Shepard into a suborbital arc.

I guess my question is was a 28 second firing of this 100,000 pound thurst engine. What distance would a ship with this engine achieve towards orbit.

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#121 2005-03-25 12:23:44

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,017

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

FAA Announces Next Step in Commercial Space Launch Partnership

FAA, U.S. Air Force Proposing Common Rocket Safety Standards

FAA and the U.S. Air Force are proposing common federal standards to make launching expendable rockets safer, more efficient and cheaper.

"These rules make it easier and safer to launch commercial rockets," FAA Administrator Marion Blakey said in a statement. "We can aid [the] growth of this industry with a unified set of strong safety standards and transparent rules that ease the launch application process."

The new rules formalize procedures to reduce hazards at federal and nonfederal launch sites, FAA said. Although both FAA and the Air Force still will maintain their own safety standards, they will be "technically equivalent," according to FAA. Air Force Space Command and FAA also have established a single administrative process for reviewing range users' requests to have certain requirements waived.

Sort of wondering if the rules changes will have a trickle down effort for the alternative space companies?

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#122 2005-08-15 20:19:36

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,017

Re: Richard Branson / Rutan Team Up For Orbital Flight - Five year plan to put tourists in space?

I am sure that there is another thread with virgin air and the technology block for military reasons that had been previously mentioned. It would seem that hurdle has been crossed.
U.S. Okays Virgin Galactic Spaceship Plans

These might only be a toy flight as sub orbital but it is the right direction to getting cost down.

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