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You’re right about Soyuz 1. I’m sorry. Somehow I missed that. I recounted and got 90 manned Soyuz missions, most recently Soyuz-TMA 4 which lifted off to delivered a new crew to ISS on 19 April this year.

Also I misread the number of Shuttle flights. It is not 115 but 113 to date. The reason for my errors was that I read the wrong numbers from the site I referred to.

Sorry.

It just goes to show I'm human after all and can make misteaks.(Make mine medium rare, please.)

Why not? Of course they do!

Now we’re almost in agreement here. (Worrying, isn’t it?)

All I say different is that a reusable crew transport vehicle (RCTV) should be put to one side while an expendable crew transport vehicle (ECTV) to replace Shuttle in a hurry should be a capsule so as to get things going again quickly; after all we have all the pieces already designed or built for this. An Apollo CM on top a modified SM all on top a Titan (for example) should be doable as a crash program in a couple of years. Your RCTV will take a lot longer and cost mucho dinero more too.

I don’t have to stereotype Shuttle, it does it for itself. And anything with six million parts (every one supplied by the lowest-priced vendor) is a really great argument in favor of KISS.

Thank you for confirming what I said; Shuttle is a kludge, a horse designed by a committee. Moral? Don’t let politicians design spacecraft.

You don’t know much about how cost estimates work, do you?

Shuttle was sold to Nixon on the basis of a 1971 (I think) estimate of $7bn. From 1971 to 2004 is 33 years (a third of a century) during which aerospace cost inflation has been approximately 350%. That means that at today’s prices, that $7bn would have become about $24 to 25bn. However the $7bn was, to cut a long story short, a lie. NASA knew from the very start it could never be done for that, and taking the actual cost back to 1971 dollars, it actually ended up costing $18bn. Add cost inflation to 2004 and you get $63bn. OK, I was $2bn out. What’s $2bn between friends?

Well yes, I’ll grant you that mile-high rockets might create a problem or two. But in the sort of size/weight range we’re talking about, it’s actually not an issue. It is only those blinded by conventional rocket design that suppose it is.

And diminishing returns is an interesting point to bring up here, by the way. The thing is that there is an optimum size, efficiency and cost for most engineering and other systems. This means that, in the case of a rocket if it strays too far from the optimums, it becomes either unable to fly, too expensive to fly, or too unreliable to fly. This can mean that a vehicle is too big to be effective for one of these reasons, or too small. Too small is a “diminishing returns” effect too. What is too big or too small for a particular system depends on how the system is supposed to operate and what it is supposed to achieve. It is my view (along with many others) that the optimum size for a simple booster that does not try to get fancy with its propulsion systems, etc. (that is, a BDB) is from Saturn V size up to a liftoff mass of maybe 20,000 to 30,000 tons, which at that upper end could haul well over 1,000 tons to LEO all in one go. On the other hand, a spaceplane is just at the very limits of doable today. There are bits of it we really have still to invent (the propulsion system, for example) which means it will be extortionately expensive to develop, and then will deliver tiny payloads at extreme cost and risk. Come back in 20 or 30 years and that may have all changed, but meanwhile it’s really just pie in the sky.

Why? Sea Dragon (mentioned earlier) weighs 20,000 tons at lift off – from the ocean.
It’s first stage would be fabricated from one inch thick steel in a shipyard… these things are far more rugged than what we’re used to up to now. The idea is to parachute the first stage back down to the ocean and re-use it, but that’s not essential for economic viability.

And give me one good reason why it would need more engineers to prepare for flight—or to fly (remember it’s unmanned) than a smaller booster. Indeed, by having sturdier components (such as tanking) and pressure fed rather than turbopumped engines, it would take far less engineering time to prep and fly than any small conventional booster. And guidance and navigation is a function of the flightpath, not the size of the vehicle.

Less, as I said above. It’s boilerplate assembled in a shipyard. Compared with conventional spaceframes, that’s real cheap.

How can you say what a Saturn V would cost today? And are big things always harder to work with than smaller? Where did you get that quaint notionfrom? How big is you TV screen back home? 25 inch? 30 inch? – or your computer’s screen? Gee, if you just had a one inch screen, it would be so much easier to work with. (You said it, not me.)

Using hydrogen is a typical design error, in many cases. Yes, it’s very light. That’s half its problem. It means the size of tankage required to hold it (and so the size and weight of the spaceplane) is so much greater than most other fuel, most of the hydrogen advantage is lost right there. The other half of its problem is the difficulty of keeping it stored at its very low liquid temperature which means much heavier, thicker, better insulated tankage… before you know where you are, paying a ferocious price for the sake of what in the end is really just fashion.

The spaceplane will more likely than not have engines with moving parts. That adds a lot to the stress in the environment you want to use them in. And anyway, you’re just plain wrong. Boosters, especially ones with pressure fed engines without turbopumps, have much less stress for a minute fraction of the time a spaceplane is exposed. – especially if you’re planning to have your spaceplane go through that stress environment on a regular basis, week after week after week. The BDB is exposed only once; it’s FAR safer.

So why call it a spaceplane?

You really should stick to things you know about. Of course it was, launched ontop a conventional booster because the horizontal takeoff spaceplane is about 30 years beyond today’s technology.

Sorry, but that’s better than no escape route whatever, which is what a spaceplane offers

Sorry, but at this point in our technology, a spaceplane (and indeed Shuttle before it) is precisely complexity for the sake of complexity. It’s like doing something to show how clever we are rather than doing what’s needed to deliver the result we all want.

The point is, we do NOT know it will work. And I’m trying to keep away from science fiction here.

Then why is it if anything getting more dangerous to fly in, not less?

Because it's true?

Man-rated is defined as 99.9%. So by your own words, Shuttle is not man-rated. Which is my point.

No sorry,  it's not. The Russian record is better, for a start. And America has lost not one man from a capsule accident while in flight. yet.

 
Agreed. I have always advocated complete separation of cargo and people. Failure to do this is one of the major fatal failings of Shuttle.

Why is it more competitive? The evidence is in the exact opposite direction. (Shuttle again.)

True again. But why make it more expensive and harder that it need be?

Thank God for google and Amazon one-click. . .
LEO on the Cheap - the top google link

I suppose you could call that LEO on the Cheap on the cheap.

This article about the sins of heavy lift is so wrong it's laughable. The only danger is that some people might believe what it says.

Do you suppose the author does? He is scraping the bottom of the barrel to find reasons against heavy lift. For instance:-

"Heavy-lift vehicles would require little in the way of in-space infrastructure to mount a mission: no space stations, propellant depots, or other facilities, just launch and go. Given that this would be supplied by an expensive heavy-lift vehicle with no other applications, it would be easy for a future Administration or Congress to terminate the program and leave virtually nothing left of government manned spaceflight. This is hardly the hallmark of a program that is supposed to be affordable and sustainable"

Uh, reality check here!

What he's really telling us is that heavy lift would be bad because it's cheap!

The true situation is the exact opposite to what he says. Without heavy lift, there will be no space stations, propellant depots, or other facilities to send lightweights to, or use -- or at least very little. There will be one $100 billion ISS that has been put up there 15 years late in about 30 separate lifts by light and medium lift vehicles. Two Saturn V lifts (for example) would have been plenty.

Even if it cost $50 billion to develop a new Saturn V class booster (which it would not come close to) and $1 billion to launch one (which it would not) because the whole space station could be almost entirely assembled on earth first, the ISS total cost would probably have been something like $70 billion. That's $30 billion and up to 15 years saved right away. And after that, with the heavy lift vehicle development cost written off on the ISS, it would be a really low-cost way to get things to LEO in seriously large chunks.

The real iron of the whole thing is that the author then goes on to talk about big dumb boosters (BDB) as part of the solution!

"At last month’s Space Access ’04 conference in Phoenix, George Herbert of Retro Aerospace made the case for just such an alternative launch system. He envisioned vehicles that could carry bulk cargoes, which he defined as costing an order of magnitude less than the vehicle itself."

Doesn't he know that George Herbert is, along with Bob Truex, one of the two prophets of BDB? George Herbert wants to build a vehicle he calls GRAND that will use the Shuttle ET powered by two SSMEs as SECOND stage to lift 400 tons to LEO or 100 to Mars. If that's not heavy lift, what is?

Heavy lift is the ONLY way to build a real space infrastructure. Don't let anybody kid you into believing different.

(Sorry, I got fed up and went away to do other things after the earler thread 'imploded'. I've only just discovered that it had come back from the dead in this thread.)

Shuttle II?

Please, please, no! This is the way to dusty death for US manned space.

Shuttle I has been such a total catastrophic failure, have we learned nothing?

And, getting back to DH-1, that's also what's so worrying about it. Shuttle, we were promised by NASA would deliver payload to LEO for $60/lb.The last time I looked, it was more like $20,000/lb.

Shuttle would turn around and fly again within a couple of weeks. One year is nearer the actuality.

Shuttle, we were all assured, would be as safe as an airliner. Shuttle has an actual, track-record, reliability of about 97%. Man-rated is 99.9%. Shuttle should never fly again, on its record.

Do these costs, turnaround times, and safety levels remind you of anything we've been taking about here? DH-1, for example?

I'm not suggesting DH-1 will turn out to be 333 times more expensive per lb/LEO, or 20 or 30 times slower to turn around, or abour 30 times less safe to fly, than promised. I'm jsut saying it might be a lot more expensive, slower to turn around, and dangerous than advertised. After all, if NASA can be so far out, why should we believe a bunch or (sorry about this) relative amateurs?

Shuttle is a disaster, but it isn't a spaceplane; its a conventional rocket with an airplane-shaped upper stage with a trio of experimental rockets in the back.

-- Shuttle isn’t a spaceplane, true. What it is is a rocket that takes wings up with it for the sole purpose of bringing them back again. The Flying Brickyard is really an abortion of a vehicle—a horse designed by a committee, which is known as a camel.   

-- It would have been far better to stick with ELVs, like the Russians did (and have shown was the correct route) as with Shuttle we just got ourselves the worst of both worlds.

-- For as long as I can remember, it has been a sort of article of faith that RLV must be cheaper than ELV. The thing is that it is Just Not True! There are several reasons why it is Just Not True, but they really all boil down to what you might call the Concorde Syndrome.

-- Concorde was recently taken out of service because it was proving too expensive and difficult for British Airways and Air France to maintain in operation, despite effectively being given the aircraft free by the government who had swallowed the entire development and construction costs. This was the only way any airline could afforded to fly Concorde; at true cost (that is, including development and construction amortisation) no airline would have flow it for even one day. A large part of Concorde’s cost problem was its very short production run. If two or three or more hundred Concordes had been sold then there might have been a very different story.

-- So has it been for Shuttle. If there had been a hundred or more Shuttles required; if the thing had flown on time; if it have been designed and built on cost; if there had been anything like the demand that NASA had forecast; if it had been able to be turned around and re-flown with the frequency forecast… but none of that happened. The sad truth is that the whole concept was based on a fallacy, and to this day most people don’t seem to see that.

-- Reusable systems (be they spaceships, aircraft, or anything else) are only cheaper than expendable systems if they are going to be used frequently enough or if enough of them are needed, or both, to absorb their very much higher design, development and construction costs. NASA based their justification of Shuttle on all the wrong assumptions, in particular that the traffic demand would justify reusability. In other words, “Build them and they will come.”

-- However the traffic never came close to justifying its costs, and so the Shuttle is inexorably inflicted with the Concorde Syndrome. In large measure due to it costing so much to develop, the Shuttle starts out into the marketplace with a price tag for lb/LEO very much higher than forecast, which apart from any other reason resulted in much less business than forecast. So the traffic does not cover the vehicle’s cost, hence the vehicle’s cost/lb go up. So there is even less traffic, and the cost/lb goes up again. As a result there is even less traffic … Today we have the absurd situation where sending a pound to LEO by Shuttle costs (in constant dollars) several time more  than it did using Saturn over a third of a century ago. Since the commission to the Saturn engineers was to get the thing to work and never mind the cost and the commission to the Shuttle engineers was to build a system that cost much less than Saturn, it’s abject failure is clear for all to see, or should be.

-- All-in-all, Shuttle has proved an excellent way to throttle the US manned space programme. To go for another so-called cheap re-usable launch system that would inevitable end up being extremely expensive, unreliable and late would probably kill off US manned space flight completely.

-- Things are that serious. Learn the lesson that RLVs are NOT cheaper than ELVs or die as a spacefaring nation. That serious.

"I would like to add that Kromer is a physists and not an economist... nobody will invest in such a vehicle unless it has a purpose. This is a pretty solid law of economics, that the certainty of return on investment is a substantial barrier to said investment. Building a mode of transportation without profitable destination is economically illogical, a catch 22 if there is one."

-- I presume you meant to say, "LACK of certainty of return…" In which case, hear, hear. I was trying to make the same point whan I talked earlier about scheduled commerical flights to the North Pole, or rather the lack of them.

Launch Vehicle tanks weight about 0.5-1.0 lb/ft^3 so using an inflatable structure or an assembled tanks from parts, 5000lb is a habitation structure of about 5000-10000 ft^3.

--  I don’t fancy living an orbiting balloon. How are you going to protect it from space debris and asteroidal collision, for example? Or what happens during a Solar flare? Better stick to using balloons nearer sea level as I suggested earlier, as a (much cheaper) alternative to Stage One.

--  Anyway, you have just described an empty balloon. Don’t you think it might need some things in it to make it habitable?

Further the DH-1 is designed as will be discussed in later chapters to be flown with a max first stage fuel wt and an optimal trajectory can but up about 12,000 lbs in LEO at a higher cost.

--  This sounds very odd, from what I read of the book so far. I suppose an all-automatic mission would help, but not that much surely? Why would you ever fly it with LESS than max First Stage fuel and optimal trajectory in the first place?

If routine assess to space is available at low cost we can learn to assemble large structures in space.

--  Firstly, it might be smarter to learn how to assemble large structures in space first, and only then think about routine delivery of itsy-bitsy payloads.

--  Secondly, the cheapest and most practical way to assemble large structures in space is to assemble them down here and then orbit them pretty much completed, using a BDB.

The south pole station was built with C-130 with a payload of only 12,200 kilograms to the pole.

--  12,200 kg is about 5.35 times the DH-1 payload.

--   Assembly at the South Pole has its difficulties, but vacuum and zero gee are not among them. And there are still no regular scheduled commercial flights to the South Pole any more than to the North Pole. My point remains unanswered.

There is no market? IBM thought the market for computers was what 8-12. Who said there is no market for computers in the home? $100 billion was spent on fiber optic cables and we are using what 5% of it. New markets do arise if only some one build new capability. 

--  Moore’s Law does not apply to space flight. Computers are an exceptional case. The price and demand curves for other things have not followed the almost unique example of computing. And if only 5% of fiber optic cable capacity is used, that’s a classic example of over-provision. Imagine how much cheaper it would have been to install a network that actually matched requirements.

--  New markets do arise if someone builds the capacity-- occasionally. “Build a better mousetrap and the world will beat a path to your door.” Usually they don’t and the capacity (or mousetrap) builder goes bust.

--  Of course, a large part of your trouble is that you don’t offer a better mousetrap. 5Klb in LEO is far too lightweight to boost a useful payload to GEO, and even the 12Klb to LEO you mysteriously pulled out of your hat earlier is not enough. But GEO is where people want their satellites to go. That needs at least 20Klb, better still 30Klb.

The Saturn V and the Energia were not low cost.

--  Compared with what we have today, Saturn V was, especially compared with Shuttle. If it was being built again today, Saturn V would be the cheapest launch platform around by a mile. And if you know how much Energia cost, you must be a rare individual. I’ve been trying to find out for some time; certainly the Russians are not telling.

Beal aerospace spent $200 million on a big dumb booster and gave up.

--  Beal’s vehicle was not a BDB. For a start, it was not nearly big enough, by a long shot.

No one has ever built a big dumb booster. And those who have tried know it’s not so easy. Why did Space-X, who has people from TRW go with a pump fed stage.

--  No one has ever tried, so how can they know?

--  No one has ever tried to build a reusable either, so how do you know it’s easy, or cheap, or both? (Except Shuttle—which is really only a semi-reusable, or more accurately, semi-refurbishable—if you insist. And that was and is neither cheap nor easy… to say the least.)

My reply to author’s reply_

Firstly may I say thank you for replying to my questions. However as you will see below, I still do not agree with much of the plan.

Author’s reply;

(1) 'Build it and they (customers) will come' has already been tried. It's called 'Shuttle'. They did not come.

1. The Shuttle was a government program and was never aimed at making money.

(1 again) … and despite that, they STILL did not come. No, your business plan would not work; there just is not the traffic. What’s needed is cheap access to LEO that also offers something else not available today, like true heavy lift. Then you could do useful things like hoisting the ISS in a couple of lifts, or a manned expedition to Mars in the same. Yes you could do this with DH-1, but it delivers to orbit penny-piece loads that would make shuttle look like a heavy lifter, which means an AWFUL lot of assembly space walks in LEO— which is asking for disaster, quite apart from anything else. If you doubt this, look at the state of Shuttle today.

(2) Don't forget NASA promised Shuttle would deliver payload to LEO for $60/lb. The actual true cost is a closely guarded NASA secret, but it's certainly well over $10,000/lb and may be as much as $20,000/lb. (That's why it's a secret.)

2. In the book the Company sells launch vehicles at $250,000,000 a pop. As will be discussed in the epilog it takes ten years of operating the vehicles at a loss to get to low cost transportation.

(2 again) Sorry, I don’t believe your quarter billon dollar unit cost. I think you grossly underestimate development costs for one thing, and then the size of the potential buyer’s market for DH-1. If you picked up (directly or by vehicles sold to others) the entire market for payloads of the mass you promise, you would still only need maybe two or three for the whole world. On that basis your breakeven selling price is probably more like 2.5 billion dollars each*, say, which puts the probable cost/lb to LEO at $2,000 or so. Maybe more, unlikely to be less. Remember that fundamentally, cost/lb to LEO is the only thing that matters. Expendables would be a lot cheaper, but see below on that.

* You ignore the effect of amortization and interest (what you might call the financing cost) on costs, as I have above also. Real world, you (and I) could not do that, and over say ten years these might come close to doubling actual real folding money required. That might push cost/lb to LEO up to something more like $3,500, real world.

(3) In that light, TRC's promise of $200/lb to orbit (which, allowing for inflation, is just about the same as NASA’s famous $60/lb promise) must be taken with a gigantic pinch of salt. In the first place, it represents a price reduction from the real-life Shuttle cost of between 50 and 100-fold. The very best achieved today, by the Russians and ESA, is around $4,000 to $5,000, and these are not manned vehicles. But TRC promises a manned vehicle that's 20 to 25 times cheaper. Yeh, right. If I were you, I'd not be holding my breath.

3. We know that cost of many products has fallen dramatically over time if there is no fundamental reason why they can’t. The Saturn V used 22 lb of propellent per pound to orbit. Or about $5 a pound. That said no one knows how the possibility of low cost space transportation, will be achieved. The point of the book is to say; sell the vehicle not the services and used no new exotic technology in the vehicle.

(3 again) The cost of propellant/lb to LEO always has been an almost insignificant fraction of the total cost/lb. So? As for selling the vehicle … well, I’ve already stated that I don’t believe the market exists.

(4) What's more, the additional cost of man-rating a vehicle has been disregarded in all this, but you can generally assume it will increase design and build cost by at least 100%.

4. For a reusable it does not cost more because the reliability is need anyway.

(5) What's yet more is the additional cost of design and build to make a vehicle re-usable rather than expendable is also ignored. Another 100% on top again, please.

5. The development cost is set at $3-7,000,000,000 about that of a new jet transport. The technology proposed is less complex than a jet airliner and the vehicle is a lot smaller. The Falcon V under development by Space-X has twice the payload at a cost of $12,000,000 vs $250 million for the DH-1.

(4 & 5 again) Designing and building for man-rating and for reusability are not the same thing.

(5 again) If we take the median development cost, $5 billion, add on say $4 billion financing costs, we have spent $9 billion before we build a single production line vehicle.

Let’s say, in line with your belief, oh… 100 are ordered in the first decade and you want to break even by the end of that period. That means development and financing have to be able to write off some $90 million against every sale, which means you have a budget of $160 million for everything else in order to sell at $250 million/unit without loss— or profit either. Can you do that? On the other hand, suppose just 10 are ordered in that decade. In that case development and financing have to be able to write off some $900 million against every sale before you even start building the first “for sale” unit. And if my guesstimate of, say, 3 units turns out to be right, development and financing have to be able to write off some $2.7 billion against every sale before you even start building that first “for sale” unit. And of course, the fewer units sold, the more each unit will cost to make anyway as it becomes less and less practical to use production-line techniques; they’ll effectively be hand built, which is not cheap.

If you think you can make this thing profitable you're a braver man than I am, Gunga Din.

(6) What on earth is the point of a pilot in Stage One? I thought elevator operators had died out as a breed some time back. With its straight up, straight down flight path, I doubt it would take even a particularly expensive computer to do the job— say one of today’s laptops?

6. A pilot will make the stage more reliable and in the long run a piloted stage is going to be easier to license for launch near population centers.

(6 again) Read your answer to point (7) below; you’ve said it. Stage One, whatever it is, it is not an aircraft. A pilot will not make it more reliable, rather the reverse. He’d just be a liability. And I don’t fancy being the poor sucker who has to abandon ship (even if complete with parachute) at 200,000 feet. And which population centers were you planning to launching DH-1 near in any case?

(7) There is also no word about flying Stage Two in unmanned mode. But this is vital. As we have learned from the history of Shuttle it is clear that risking men on missions that don’t need men, such as delivering cargo pure and simple, is almost criminal. That’s apart from the obvious fact that an unmanned version could deliver more payload to orbit.

7. Unmanned aircraft are less reliable, unmanned space vehicles more so.

(7 again) You said it. So where’s the unmanned DH-1?

(8) Flying Stage One straight up and down again is an amusing notion, but an exceptionally inefficient way to get the payload into orbit. Existing launch vehicles follow the trajectory they do not for fun but because it is significantly more effective than this proposal. But what about recovering Stage One?……

8. The DH-1 is not a missile where max payload/min wt is important, for the DH-1 nothing matters but overall cost. The DH-1 losses only about 30-40% of it payload by flying the trajectory which is optimized for ease of recover of the first stage. The vehicle should not be compared to a optimized two stage but to a single stage. It has better payload and lower development cost than a single stage but retains much of the simplicity of operation of that of a single stage.   

(8 again) Close, but no cigar. You’re on the button about the over-riding importance of cost. But all you’re doing with Stage One is getting Stage Two above the atmosphere. You could achieve the same result with the benefit of adding significant forward velocity by abandoning Stage One and strapping a couple or more solid rocket boosters to Stage Two; I bet if these boosters were discarded and so written off after each launch, that would still work out cheaper than your Stage One. And you’d probably double your payload to LEO into the bargain.

(9) Don’t bother recovering Stage One. By making it expendable a fortune would be saved, as it would not have to be built for reuse. Recovering and refurbishing the Shuttle’s solid rocket boosters almost certainly costs more than letting them sink and building new ones. Which leads naturally to…

9. The first stage is very simple and would need little or no refurbishment between flights. An expandable stages of the same size will cost 2-5 million even from a company like Space-X and of course if it is manned rated it will cost a lot more. An expendable stage also does not fit the proposed marketing plan.

(9 again) I think you’d find that NASA sold (or were sold) on the Shuttle’s SRBs on the basis that they would be “very simple and would need little or no refurbishment between flights”. If you still believe that— or if you are falling for the same line again— I’ve got a bridge to sell you.

You want simple? I’ll give you simple. Solid rocket boosters (I don’t mean the ones stuck on Shuttle) would probably be significantly cheaper that your Stage One. Go work it out. But I’ve another idea. Stage Two could be lifted almost as high as Stage One manages (certainly over 100,000 feet, possibly 150,000 feet) by slinging it under a gigantic helium balloon. Don’t laugh. Why not? The balloon is of course expendable, but that’s peanuts. And you don’t have to bother with Stage One or solid rocket boosters, etc. at all. You’d save a very considerable fraction of your costs, and that gives you ‘simple’ in spades. Go ballooning!

(10) Recoverable launch systems (RLS) will only become cheaper than expendable launch systems (ELS) when there is far more traffic than today. And as already pointed out, there is absolutely no assurance that low cost to LEO will deliver more business in a short enough time to prevent the RLS makers going bust in the meantime. If NASA had not been a government agency, I think it’s clear that Shuttle would have bankrupted them long ago.

10. I have to agree, for a RLV to be economical there must be a lot more traffic, but there must be a lot lower launch cost in order to get more traffic.  It is a classic chicken and egg problem. The book presents one proposed solution to the problem. The market for a manned RLV might be different than the market for launch services, and if a number were sold, the market of services would grow.

(10 again) That’s why the way to go is, firstly a seriously big low-cost booster, which could well be a resurrected Saturn, to get serious amounts of hardware up there such as space stations Mars and Moon missions and colonies, perhaps even the start of solar power satellites and eventually, O’Neal-type colonies. For all of these, and others what will appear once we start building a serious space infrastructure, DH-1 is far too lightweight. But the BDB is not man-rated; there is an urgent need for a new manned vehicle to replace Shuttle as soon as possible. Maybe that will be where DH-1 will have a place, or something similar— except there’s not enough time to wait without another way right away. That’s why I favor resurrecting the Apollo command module reconfigured to take up to 6 people and launching with a Adriane 5 or similar.

You might call this plan “Back to the Future” J

(11) No-one should ever forget that today we have the absurd situation where sending a given payload to LEO by Shuttle costs several time more than it did using Saturn (in constant dollars) over a third of a century ago. Since the instruction to the Saturn engineers was to get the thing to work never mind the cost, and the Shuttle was justified almost solely on the basis of its cheapness compared with expendable systems, it’s abject failure is clear to all to see, or should be.

11. The situation today is hard to understand and it is not just the US and NASA that have problems nobody has found a low cost solution to the problem of space launch. The book is an attempt to look at the reasons why space transportation costs have not fallen very far and proposes a possible solution. More importantly the aim is to educate, and perhaps contribute to better design solutions in the future.  No more NASP or X-33 or Buran, billions spent with no results.

(11 again) I commend your mission to educate, but (as you probably figured by now) disagree with your proposed answer. And yes, everyone has problems finding a low cost solution. But you must admit that NASA, with their Shuttle, takes the biscuit, with a so-called “low cost solution” that is actually several time more expensive than the ELV it was built to replace. It would be funny if it were not so pathetic, and so sad.

(12) Certainly the day must come when re-usable SSTO systems will be the way to go into space, but that day is most certainly not yet. What NASA ignored when lobbying for funds for Shuttle, and what people like TRC continue to ignore, is that at the present state of our technology, the cost of designing and building a re-usable vehicle makes such a so-called cheap system horrendously expensive. Indeed it is far more expensive than an expendable system in terms of the only measure that matters, which is cost per kilogram of payload to LEO.

12.  The day is not yet, but the book argues it not the technology that is postponing the day, it is pursuing the wrong markets and wrong technology that give space launch a bad name.  It is certainty true that a reusable vehicle is not cheaper unless the market for launch services is large maybe 10-1000 times larger than existing markets.  The book tries to show one way that it might be possible to drive down launch cost with out a large transportation market, by selling launch vehicles.  Only about 5% about of fiber optic cable band width was in uses in 2001. It may have made no senses to build so much bandwidth, but the fibers networks were built and cost for bandwidth are falling and demand is growing.

Something like that is need for space transportation.

(12 again) But if there is no large transportation market, who’ll buy your launch vehicles in the first place? As I said earlier, 2 or 3 vehicles would more than fulfil foreseeable demand for the total world market, and that includes the fraction which is military or otherwise classified that you would not get a sniff at any case. Also, from my back-of-envelope  calculations, your LEO payload is not enough to boost the typical mass of today’s GEO satellites to GEO orbit, so bang goes another half of your market.

Late last year I had an article published in ‘Spaceflight’ which is published by the British Interplanetary Society. To give you a better idea of where I’m coming from, I’ll copy it here:-

Cheap Access To Space
By Jim Mangles

In 2003 we celebrate the 100th anniversary of powered heavier-than-air flight. The progress of flight over that time was impressive. Indeed, 50 years after Kitty Hawk, millions had flown, jet engines were in daily use, and the sound barrier smashed.

However we’re not likely to celebrate 2011 as the 50th birthday of manned space flight enthusiastically because there’s not likely to be much to celebrate. As things are, a few hundred people will have visited near-earth space and twelve landed on the Moon, but the last came home 39 years earlier. The most modern manned spacecraft will be a 40 year old design flying 7% as frequently, costing 16 to 33 times more than promised[1,2], and with a safety record that would ground any similarly performing aircraft[3]. Oh, and there’ll be a 15-year-late, over-budget space station with a tiny crew as it’s too expensive to have enough people up there to do more than keep it ticking over and, well, that’s about it.

Is this really the best we can do? Must we resign ourselves to a pathetic manned space effort that is both depressing for us, an insult to the early pioneers, and inspiring to no-one?

No! There is still time to make 2011 a worthy 50th anniversary.

The single most serious handicap facing manned spaceflight today is the extortionate cost of getting to LEO. If things had been as Shuttle had promised rather than delivered, it would be very different now. But now Shuttle’s failings make the need for a successor obvious and urgent.

Cheap access is the essential element missing from today’s arthritic manned space efforts, yet it is well within our grasp if we just looked in the right direction. Indeed, there’s no lack of proposed directions. Unfortunately almost all require long lead times, huge R&D budgets—and usually both. Shuttle itself was an expensive project that promised cheapness by frequent use. It failed to deliver for two reasons: firstly because it was technically impossible to turn a Shuttle around anything like fast enough; and secondly because there was just no demand for flights every few days at the prices Shuttle really cost.

I believe any attempt to replace Shuttle with a Super-Shuttle, space-plane or SSTO vehicle will fall foul of the same fundamental problems. This even applies to something so seemingly attractive as Bob Truax’s Sea Dragon Big Dumb Booster. Anything needing development from scratch should be put aside for now. It takes too long and costs too much; we’ll come back to build them later. Instead let’s get moving now with what we’ve got now.

But that’s a lot, if we just look.

Firstly, we should separate cargo launches from crew. It makes zero sense to risk people unnecessarily.

In 1968 NASA asked von Braun’s team to investigate development possibilities of the 118 tonnes-to-LEO Saturn V built for Apollo. Out of many ideas, here’s the biggest one—the V-D[4]. At 9,880 tonnes it’s a lot lighter than Sea Dragon’s 18,000 tonnes, but V-D could orbit 326 tonnes versus 450 tonnes. And no new ocean launch system is needed, just existing Florida facilities with a larger Transporter. Payload cost was estimated back then at $2,260/Kg, but there’s good reason to think a modern V-D would be cheaper by now—$1,000/Kg is a conservative estimate. At 10 to 20 times cheaper than Shuttle, this would cost less per mission than Shuttle.

Yes, Saturn is history, with drawings reputedly lost[5]. But even so we know we can build something like this; we did 36 years ago. In fact, we should be able to do better now, just so long as we can resist endless improvements. Good engineers know when to freeze designs.

An obvious question is, where do we find enough 326 tonne payloads?

Of course, we’d start with the 118 tonne version and grow with the traffic; still, who would want 326 tonne lifts? Apart from launching the entire ISS in one go, the answer is almost everything going up today, plus lots more that wouldn’t or couldn’t now. With vastly cheaper LEO delivery than anyone else, almost all today’s payloads will use what I’ll call Saturn-II. It can be used as a bus for many separate packages, including those for GEO and interplanetary missions.

And low cost delivery means lots more business. If it costs much less to orbit a package, the package does not have to be super-reliable as it’s cheap to replace. Thus the cost of space falls. Missions to Mars, Moon bases, and other over-ambitious manned missions today, now become quite reasonable.

Saturn-II is unmanned. So, we need a rapidly available, effective vehicle to get people to and from LEO safely.

I believe the safest and quickest answer is to rebuild Apollo; or rather, use the same geometry but completely redesign the interior[6]. It will need a launch vehicle, but suitable boosters are available today. For example, the USAF’s Titan 4 can hoist 17.7 tonnes to LEO and ESA’s Ariane 5, 18 tonnes. And there will be cheaper, better matched alternatives. Whatever is chosen has to be man-rated of course, but in any case Apollo-II will lift off with an escape tower, unlike Shuttle.

Apollo-II should be developed as soon as possible. NASA says 6 to 8 years, so it should be feasible in 2 to 4, as should Saturn-II.

These two old/new vehicles make it possible to build a future for manned spaceflight again, and they could be operational by 2011. However, there is one essential proviso. With its remarkable ability to bureaucratize, delay and vastly overspend, NASA must be excluded from all this.

Instead, I propose an entirely new CATS Corp. with the sole job of delivering people and things to LEO cheaply. Customers, including NASA, would pay for delivery just like they do for terrestrial delivery today. Then, from 100% Government ownership and initially using funds diverted from NASA as Shuttle runs down, CATS should soon become transformed into a normal company trading on the market. 

At last space access would be cheap, self-financing and finally—glory be— beyond the vagaries of politicians.

[1] For simplicity, all prices are in 2002 US $’s
[2] The original mid-1965 Space Shuttle Mission Profile forecast first flight in 1975, building to 60 or more per year by 1978. If 60+ flights/year had continued to mid-2003, there would have been about 1,650 by then, with payloads costing $600 per Kg. In fact it first orbited in 1981 and had flown 115 times by mid 2003, including its 2 disasters. The true payload cost is hard to tie down, but lies in the range of $10,000 to $20,000 per Kg—far more than Saturn. Objectively, Shuttle has been a giant leap backwards.
[3] A man-rated launch system is one that is 99.8% reliable. Historically Shuttle is now 98.26% reliable and so technically is no longer man-rated.
[4] More information is available at [http://www.astronautix.com/lvs/saturnvd.htm]http://www.astronautix.com/lvs/saturnvd.htm
[5] Some in NASA say a complete set of Saturn drawings are held at the Library of Congress.
[6] More information available at [http://www.spaceref.com/news/viewsr.html?pid=9031]http://www.spaceref.com/news/viewsr.html?pid=9031

"If you want cheap launching to space the vehicles have to be reusable; expendables can't do that now, and it isn't clear that even with an economy of scale that will be possible."

Sorry, this is a myth. Going reusable at this stage in the space launching business is trying to run while you can still barely crawl. It is bound to lead to disastrous failure.

One reason is that whatever the TRC people say, developing and then flying a reusable involves far more design and research time and cost than they seem to imagine. You say, "The approach of the Rocket Company seems to be that simple tried and true technology is often the way to go..." but it is not in every case, by a mile. Just to take one small example, the idea of a heat shield that can be deployed at the rear of the vehicle to cover the engines and so permit rear-first reentry is interesting but has never been done in real life. I'd bet just to get that alone working with reasonable reliability and safety would probably cost a couple of billion dollars.

"Why put a pilot in the first stage?... With good computers, rockets don't explode nowadays; if an engine has a serious problem it is shut down. The pilot can eject from the stage in an emergency." So why put him there in the first place? If the computers are good enough to prevent the rocket exploding (which I most sincerely doubt) they are for sure good enough to take Stage One up vertically, down vertically, and land it. Further, the human pilot could not see the ground directly (look at the shape of the vehicle) so he would be depending on the computer in any case. No, he is 100% redundant; really he's just a liability. And man-rating Stage One would also cost a fortune— another couple of billion?

I could go one. However, more generally, the idea that reusability equals cheapness is an article of faith by those who like the idea of reusable launch vehicles (RLV), but it is just not born out by reality.

The unpalatable truth for these people is that until there is an EXISTING demand for several flights to LEO per week or even per day, expendable launch vehicles (ELV) will always be cheaper.

There are several reasons for this, and I could expand on this theme for days, but in summary here are a couple of the main ones:

(1) ELVs cost much less than RLVs to design, develop and build because they do not have to be used again. Throwaway goods in everyday life often are cheaper to use than reusable equivalents for the same reason.

(2) ELVs do not have to be brought back down, so they are much less complex than RLVs and don't require fancy reentry systems.

The basic, vital thing to remember is that the purpose of all these plans and projects is to drastically reduce the cost of getting to orbit. Everything else is secondary and unimportant. If the cheapest way was to fly there on a chariot pulled by geese, then so be it.

And in fact with today's knowledge the rational way to go is to build a large, expandable launch system to be used for cargo only; ideally something like Bob Truax's Sea Dragon Big Dumb Booster, but if not that, then you could do worse than rebuilding Saturn V, which nowadays could deliver 130 tons to LEO for lass than $500/lb. Being cargo only, it would not have to be man-rated, which cuts costs in half right away. Being expendable does the same again.

But really it does not matter what expendable vehicle is chosen; I would not object to an all solids vehicle if that were the cheapest. I don't care what the Isp is; I don't care what the mass ratio is. All I care about is getting the stuff up there as cheaply as possible. And that assuredly is not by way of a semi-SSTO RLV.

To get a better understanding of where I'm coming from, I strongly recommend you get hold of the book 'LEO on the Cheap' by Lt Col John R London III. Truly, it is an eye-opener.