Talk: Rocket
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I apologize for the USA-centric references in the initial article. Please list significant USSR/Russian developments where appropriate. -- ansible
Removed reference to nuclear rockets being against treaty. Nuclear pulse rockets would have problems, but there is no treaty to prevent the use of nuclear thermal ones.
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Propellant for "Fuel"
In the Art, the term "fuel" is exclusively used for the energetic or combustible component of the rocket propellant combination as contrasted to the "oxidizer". The combination of both (in a bi-propellant system) is termed "Propellant". In the case of a single substance it is termed "Monopropellant". In hetero or homogenous solid compositions they are termed "Solid Propellants". The article will be improved thereby by substituting "Propellant" for every instance of "Fuel".
BC
Done. -- DavidCary 15:12, 13 May 2004 (UTC)
"A rocket is any device that propels itself using reaction mass; see Newton's 3rd Law of Motion".
- Actually the complete sentence currently reads: "A rocket is a vehicle, missile or aircraft which obtains thrust by the reaction to the ejection of a fast moving exhaust from within a rocket engine."
- Now, I can understand if that sounds a bit circular; but it really isn't.
I don't feel this definition is at all accurate. It applies also to jet engines
- Conventional jet engines and rocket engines involve combustion and jets of hot gas from nozzles, but rocket engines very definitely do have big differences from jet engines- jets have air inlets, rockets don't; the exhaust speed from a jet engine is almost an order of magnitude lower than from a rocket engine; the chemistry of the exhaust if vastly different- rocket engines run extremely fuel rich as this increases the exhaust velocity; jet engines run 'air rich' as this keeps the exhaust velocity as low as possible.
and even a catapult
- Not really possessing a rocket engine though. There's no nozzle.
- such a device could be used to propel a vehicle by throwing a rock backwards.
- Yup. Does it have a rocket engine though?
A proper succint definition is quite elusive; the OED and Macmillan Encyclopedia for example have quite long-winded definitions, so they've run into the same problem. Macmillan states: "vehicle or missiles powered by jet propulsion that carry their own fuel and oxidiser...". OED has "engine containing its own propellant and depending for its operation on reaction due to continuous jet of rapidly expanding gases released in combustion of propellant". The key points are that a) the rocket carries all of its propellant including the oxidiser, and b) the reaction mass results from the combustion of this fuel. I will have a go at rewording the definition, though if anyone can think of a better one, feel free to give it a go. GRAHAMUK 03:04, 6 Dec 2003 (UTC)
- I don't feel that Macmillan captures it. I don't agree that hot gas or combustion is necessarily significant (see water rockets or steam rockets). IMO but there's probably the following properties that characterise a rocket engine:
- a) propellent is carried onboard the vehicle
- b) exhaust consists of a fluid
- c) exhaust is emitted through a nozzle that increases the speed of the fluid
- Of course there's nothing cast in stone about this list; if you tried hard enough you can doubtless come up with your own different definition.
- Note that ALL of these are necessary for an engine to be considered a rocket. Jet's have nozzles but are not rockets. Catapults could theoretically be classed as a rocket engine, but I don't feel it quite qualifies, it's just a reaction drive. Scramjets have fluid exhaust, but aren't rockets, they are jets, since they use the air as part of the propellent.
- If "combustion" becomes part of the definition of a rocket, then things like "ion thrusters" and "Nuclear thermal rockets" are technically not rockets. That's OK -- we could just call them "thrusters" or something.
- I don't see that combustion is necessary- look at water rockets. Fluid exhaust seems to me to be. Nuclear thermal is definitely a rocket in my book. Even VASIMR, since it has the hot fluid and a nozzle, and uses onboard propellent. Ion drives are pushing it, there's not really a nozzle, and it's not really a fluid, it's a plasma; but that one's very borderline.
- terminology question: what would you call other things in this tree?:
- devices that propel themselves using a reaction mass, which includes
* jet engines and other things that burn oxygen from the air
- Jet, since it sucks in the air and uses it as part of the propellent
* squid (I think people have been calling that "jet" of water long before aircraft were built).
- well, it sucks in the water before expelling it, so it has an inlet. I think you could argue that one either way, since once it has sucked it in, it works like a water rocket. I mean all rockets get filled at some point :-) On balance I'd say jet, since the inlet equipment is carried around with the vehicle, I mean creature.
* devices that carry all their propellant with them * ice skater shooting machine gun backwards
- There's no nozzle in the conventional sense, and solid exhaust; although the powder burn will provide some recoil and would count. Arguable; but I'd say not; the nozzle is not intended to increase the velocity of the burnt powder.
* ion thrusters
- No nozzle.
* Nuclear thermal rockets
- Yup. Nozzle. Fluid exhaust. No air inlet. Rocket.
* devices that burn fuel to produce the reaction mass
- If they have a nozzle, and don't suck in air, they're a rocket.
- -- DavidCary 04:53, 12 May 2004 (UTC)
- So, my 3 rules seem to work. There's clearly other rules that can apply and they may end up classifying differently- but my rules seem to be simple, and work well enough (unless anyone can come up with a clear counterexample). --Wolfkeeper 16:06, 30 May 2004 (UTC)
Suggestion for new article: space economics
- I like to see information about improvements to rocket technologies. ... (Any suggestions for exactly which article ?) -- DavidCary 17:23, 11 May 2004 (UTC)
I don't mind. A space economics article might be good. There is a transport economics article. Paul Beardsell 20:24, 11 May 2004 (UTC)
- I would support it. I wouldn't take the time to author it, but I would contribute to it. Rei 21:55, 11 May 2004 (UTC)
Or, we could put this information in an "economics" section of the Rocket article.
Need rocket costs be so high?
Asymptotic costs
In the ultimate data point; the only consumable is propellent (mainly fuel). R&D, personel costs and so forth tend to amortise away.
A typical fully loaded LOX/Kerosene rocket is 2% payload, 85% propellent.
Of this fuel 60% is LOX, 40% is Kerosene
LOX costs maybe $0.1/kg Kerosene costs about $1/kg
Thus the average propellent cost per kilogram of payload is (0.6*0.1 + 0.4*1)*0.85/0.02 = $20/kg
Allowing a generous 250kg per person (including lifesupport and a chair and luggage) this would be $5000/person.
Now, is this in any way realistic? On the face of it the answer is no. However consider airtravel; currently airtravel is running at about 2x the cost of fuel, so this suggests that this is acheivable with rockets as well (reusable rockets are really just a different form of aerospace vehicle.)
So, using the same multiplier, that's $10,000 per person.
This analysis assumes a *very* high rate of launch; >1000s of launches per year; reliable, mature reusable launchers, with low maintenance costs.
There is no known reason why this cannot be achieved.
Other resources
low cost rockets - Scorpius - cost factor reduction of 5 to 10 - funded by NASA and USAF - successful launches already. See also this and PDF slides.
cheap access to space - just an article
Falcon 2004 launch quoted at $10,000 / kg to GTO
Popular Mechanics article on a cheaper rocket engine - tested at NASA
- Saturn V - $3653 / kg LEO (1967)
- Proton - $2,500 / kg LEO (current?)
- Aerojet Sea Dragon - $70 to $620 / kg LEO (1960's)
- Mc Donell Douglas MCD - $767 / kg LEO (1968/9)
- Boeing COLV 3 - $936 / kg LEO (1968)
- Boeing MCD - $1605 / kg (independent study) LEO (1970)
- Kistler K-1 - $135m NASA contract - reusable
- NASA SLI target is $2200 / kg LEO
LEO on the Cheap see Ch9
- ...[Do] that rocket programs include their capital costs in their launch costs [or not ?]... I'd probably need to contact someone at the ESA or NASA. Do I need to do this to make you happy?
- You also keep saying that there is huge potential to advance in prices. ... but ... We've barely gotten price improvements since 1960. So, either all of the people working for all of these agencies are idiots, or you're wrong. Take your pick - you can't have them both.
- It seems some think that rocket costs can be reduced. Paul Beardsell 00:13, 11 May 2004 (UTC)
- Now, lets go into your rocket list. Your Saturn V cost is in 1967 dollars. Run it through inflation [1], and you'll be unpleasantly surprised to find out that the Saturn series is actually rather expensive, at about 20k$/kg. The Proton rocket cost, in addition to being in 1960s dollars, is widely accepted to be an anomaly due to the old Soviet accounting system. The Sea Dragon does not exist, never did, was based on pure MCD (Minimum Cost Design) extrapolation (which seldom ever works in engineering), and noone is proposing to build it. (I think we'd notice a rocket over three times the height of Niagra falls being built ;) ). Truax ranted and raved about it, of course. From 1988 to 1991, the Navy worked on a smaller version of the Sea Dragon design (as SEALAR - with way less optimistic numbers); initially encouraging, it encountered major technological problems (most notably, pressurized tank failure - that's what you get when you try and build a rocket like a ship), and it was cancelled before they even attempted a single launch. Likewise, Chrystler and McDonnel-Douglas MCDs (once again, 1960s dollars) as well as Rockwell and Boeing's MCDs (including COLV) (note that your paper includes Boeing's numbers; the numbers for the MCDs were independently assessed at 1,605-2,425$/kg in 1968 dollars), were 1960s dollars. The concept of MCD has been partially rejected in favor of RLD after long analysis. Most MCD designs were somewhat unsafe, although it is true that making the rockets larger in general also offered some advantages.
- Proton costs are not 1960 but, according to the slides, "current" as at 2002. But, you say, "widely accepted as an anomaly". Reference please. The Boeing MCD figures I gave were the ones for equitorial orbit from the independant study. The highest figure is for polar. Paul Beardsell 00:57, 11 May 2004 (UTC)
reference:
"the low stated price of the Proton 8K82K is most likely an artefact of the Soviet system" --
http://www.theculture.org/rich/sharpblue/archives/000066.html
- As for the Kistler K-1 (wow, what a jump there!), it'll be interesting to see what happens. Theoretical launch price of 17 million dollars (1997 - about 22m$ today) and payload of 4,500 kg. It is just one of many theoretical systems NASA is funding to try and bring prices down as part of SLI (the Space Launch Initiative). I think you mistook SLI for a rocket; the K1 is a rocket that is part of the SLI program. SLI is way over budget and years behind schedule. As I mentioned earlier, there are proposals in the works to try and reduce space launch via rockets to about a quarter of its current price; however, beyond that, there isn't much forseen that can lower it very much, and even reaching that level is showing to be a long and tedious process.
- ... And yet, here you are admitting a reduction to 25% is possible. Paul Beardsell 01:01, 11 May 2004 (UTC)
- ... But it seems some part of NASA is calling the rest of NASA and all the other space agencies stupid becuase they have set a target of well under $3k/kg for the SLI program. ... Paul Beardsell 00:13, 11 May 2004 (UTC)
- I can't find anything about NASA funding any of Microcosm's rockets. Now, I have found things for NASA working on things like a super-compact laser with Microcosm, navigation equipment, etc, but as for rockets, I can't find a thing. Rei 23:51, 10 May 2004 (UTC)
- If I can find something will you admit you are wrong? Paul Beardsell 00:13, 11 May 2004 (UTC)
- This is misrepresentation. You said you don't like Ariane reliability. I said choose another rocket, then. It wasn't a discussion about cost. It's all in the log. That's a change in subject. I asked you a question: Since I demonstrated that at least one rocket system (the shuttle) does NOT repay its capital costs, why do you expect that another (the Ariane) would? Why would you expect different accounting mechanisms to be used?
- My apologies about the Proton - the cited number is in 1994 dollars, which makes it about 3,200$/kg in modern dollars. However, the last launch of the 8k82k was in... 1975. You do realize that the world's space agencies would have to be idiots not to launch on the 8k82k if this were true, right? So, I'll ask again: Are They Idiots?
- There's enormous pressures on projects to choose particular launchers; if you're American, you launch on an American launcher, if you are European you launch on Ariane; failing to do this gets you in serious political trouble. Also, Ariane have an excellent sales team by all accounts, and the launcher is highly optimised for GEO launches, for example it has airconditioning of the Payload, that the Proton doesn't (or didn't) have IRC. In many ways it's the easiest path just to go with Ariane, and many payloads do just that. The Proton is harder to engineer the payload for, but ultimately cheaper. There's also payload specific issues; if your payload doesn't quite fit one launcher or is much too small for another then you end up choosing an 'expensive' $/kg launcher because it ends up cheaper for your payload, that's why Pegasus is still around for example--Wolfkeeper 13:42, 27 May 2004 (UTC)
- Furthermore, all of the more recent Proton rockets have cost notably more. *A Lot More*. For example, in 1994 dollars, the 8k82k/11S86 is over 14,000$/kg. In 1994 dollars. This is a *later revision* of the 8k82k. Are you going to try and claim that the Soviets were so idiotic that they took a gigantic step *backwards*? Please, don't skip these questions - answer them.
- You need to consider the difference between ticket price and what you can knock them down to. The Proton is enormously cheap to produce, and hence cutting a deal is commonly done; but wouldn't ever appear on the price list.--Wolfkeeper 13:42, 27 May 2004 (UTC)
- It isn't my rocket list. - you presented it as evidence, so you need to take responsibility for it. How you believe I thought the SLI was a rocket is difficult to fathom. . Because you had it in a list of rockets! If I can find something will you admit you are wrong? - About Microcosm, sure.
- I thought you said rocket cost reductions were impossible. You've been repeatedly as good as calling me a fool for saying so. And yet, here you are admitting a reduction to 25% is possible. I thought I had already mentioned that, although I can't find it in the history. There have been several programs designed to try and reach that level (in fact, the space shuttle program itself was initially trying for close to that,
- The Shuttle designers wanted to build a smaller, fully reusable vehicle, with no ceramic tiles, and a smaller payload, but the Government refused to pony up the cash. If they had gone with the original design- it had a robust metallic skin due to its reentry trajectory. In order to get anything built they had to make a deal with the airforce, and the airforce wanted heavier payload return to earth. This meant that more energy was dissipated during reentry, and necessitated ceramic reentry tiles. The tiles have been an enormous disappointment in cost terms; it takes a man-week to replace a single tile; and hundreds of tiles get damaged during a flight.--Wolfkeeper 11:35, 28 May 2004 (UTC)
- The ironic thing is that the Shuttle designers had originally asked for less overall money; they had just wanted higher peak funding. The government had said that the higher peak funding wasn't available. They settled on a compromised Shuttle design. The operating costs with the compromise design were known to be much higher; and that's todays Shuttle; and it has ended up costing the American public many, many times over what it should have.--Wolfkeeper 11:35, 28 May 2004 (UTC)
- Oh, give me a break. Back it up, and answer which shuttle designers??? (yeah, like you'd ever back it up).
- FWIW it was Max Faget- the guy who's name is on the patent application for the Shuttle
- There were tens of thousands of people working on the shuttle program; even a company that I used to work at (Rockwell-Collins) had a big contract for the shuttle. There were about 120 proposals for the overall design of the system, and dozens of designs for every single part in that whole craft. And, hell, the Nixon administration told NASA to reduce their requirements notably.
- although they were sorely disappointed
- Actually, the top guy at the time recently admitted that they never thought for a microsecond that they would achieve those costs; and they weren't even trying. The launch infrastructure to achieve that is very different to what they built; but the funding they got only paid for what they built.--Wolfkeeper 11:35, 28 May 2004 (UTC)
- "The top guy at the time" - for God's sake, Wolfkeeper, I thought you were lecturing about references earlier. And you can't even mention his name. Rei 16:53, 28 May 2004 (UTC)
- when turnaround costs ended up being a lot more than expected - as is typical). However, you're not arguing for reduction to 25%. You're arguing for a reduction to <2% to match a first-generation space elevator. That's preposterous. Utterly ludicrous. NASA is working hard to reach that (very elusive) 25%.
- NASA is funded by creating jobs in most of the states in America. The vast, vast majority of the costs of launch go on peoples wages. The way to reduce costs is to fire people that currently work on the launch platform. If they do that they lose budget and votes in the senate, and their budget gets slashed. The Shuttle is extremely labour intensive. This is a positive, not a negative, as far as the NASA organisation is concerned.--Wolfkeeper 11:35, 28 May 2004 (UTC)
- It has been a slow and painful process, with very little success to show for it so far. They're not even dreaming of ever getting anywhere close to 2% with rockets.
- Of course not. NASA as an organisation dreams of spending more. The individuals within NASA may dream of spending less- good luck to them; but NASA ain't going to take them there any time soon.--Wolfkeeper 11:35, 28 May 2004 (UTC)
- In summary, your homework for this time is to answer the following questions:
- Were the soviets such idiots that they couldn't figure out that they were making *gigantic* steps backwards with later rockets? Because this is what you would have to believe to accept them retiring the 8k82k for its later versions.
- Are the people at all of the world's current space agencies such idiots as to not revive the original 8K82K for current launches?
- Where does *anyone* at NASA currently propose using rockets to get anywhere even close to the cost of a space elevator?
- Why would you expect different accounting mechanisms to be used between the Shuttle and Ariane?
- In summary, your homework for this time is to answer the following questions:
- Answer them and get back to me. Rei 16:46, 11 May 2004 (UTC)
(i) You say they are idiots not me. (ii) Ditto. (iii) It has been shown: Rockets are cheaper than elevators until a break even amount of stuff (depending upon the type of stuff) has to be moved. (iv) I wouldn't expect anything. Paul Beardsell 20:24, 11 May 2004 (UTC)
- (1&2) You are dodging the issue, and I don't appreciate it. Reconcile them not being idiots with the fact that they went to what would be a far less efficient rocket. Go on - reconcile it. The only implication one can get from your argument is that they're idiots. If they're not idiots, explain why they trashed what you consider to be an incredibly efficient rocket for ones that are far, far less efficient. Do Not Dodge The Question.
- (3) Actually, I showed that even with the worst case, most ridiculous assumptions, a space elevator still comes up far cheaper than any rocket, and around the cost that NASA has the *goal* of *eventually* reaching with their *optimization* of rocket technology, which is proceeding *slowly*. How can you possibly claim that "it has been shown"? What was shown was the *exact opposite*. I mean, look at the numbers! A single, first generation, minimal payload space elevator, whose components are lifted to GEO by our expensive rockets, repaying all capital costs (unlike normal space programs) in 10 years (NASA's payback is due around the year NEVER), we get $3,400/kg, one third the cost of the cheapest rocket in existance. After that, it drops to less than 200$ per kilogram - with our *first generation* elevator.
- (4) Paul, you are driving me crazy by dodging the questions. Don't give me that "I wouldn't expect anything". I raised a legitimate issue. The space shuttle, as I demonstrated and has not contested, does not repay its capital costs. Do you contest this? If you do contest it, you must demonstrate that, with its 500-600 million dollar turnaround cost, that the turnaround cost doesn't equal about 10,000$ a pound for payload. If you do not contest it, but you still consider Ariane to be repaying its capital costs, then you must expect there to be different accounting. Which is it? Don't dodge my questions here - you dodged 1, 2, and 4 (and claimed something flatly contradicting the numbers shown in our discussion for #3), and I don't appreciate it one bit. Rei 21:55, 11 May 2004 (UTC)
You put words in my mouth. You insist I answer questions of the type "Have you stopped beating your wife?" You spend days attacking me because I suggested rocket costs could be reduced and this is now your position: Good, I have persuaded you. But you wish to continue. As far as I am concerned what I wanted to show has been shown. I do not want to continue this argument with you. Paul Beardsell 23:08, 11 May 2004 (UTC)
- While I completely disagree with your assessment, and I find my questions to be perfectly reasonable (you haven't addressed any of the issues I presented related to the proton's cost (why would they abandon it if it were so cheap???), to the accounting (why would they use different accounting methods???, etc), as long as you'll drop your "Its easy to lower rocket prices and a sizable percentage of people with any sort of qualifications on the subject whatsoever think they'll get anywhere close to that of a space elevator" attitude, I'm fine with that. Rei 23:46, 11 May 2004 (UTC)
Whoever is being quoted in the above paragraph it is not me. Nor is it a proper characterisation of what I have said. Paul Beardsell 00:41, 12 May 2004 (UTC)
- It's called paraphrase, Paul. If that's not what you've been arguing, please sum up your argument for us. Rei 16:05, 12 May 2004 (UTC)
The consensus seems to be that there is a potential to reduce rocketry costs to perhaps 25% of today's costs. Some private companies are getting involved and they are presumably hoping to make a profit out of their rocketry offerings so it is rational to assume capital financing costs must be factored in to their figures. Even if this potential to reduce rocketry costs is speculative, even if it takes decades to realise it seems fairer to compare the speculative costs of the future elevator with the speculative costs of future rocketry.
Paul Beardsell 10:58, 12 May 2004 (UTC)
- Also, just a quick reply to Paul: If they're developing rockets under a NASA contract, they're not expecting to get their capital costs repayed in launch costs. NASA gives contracts to companies based on how much it costs the company to develop, and then NASA owns the product. I know because I used to work for Rockwell-Collins, and they had a scandal a while back while working on a project for the shuttle (the shuttle contract had no limit, and so other projects started charging hours to it). Unless these contracts are somehow completely different and they're (strangely) paying the company in installments based on how much use it gets, they're not expecting anything along the lines of capital cost repayment from launch costs. Now, for independent organizations like Scaled Composites and the Da Vinci Project, they would probably be repaying their capital costs - but their payloads are so tiny, I doubt they'll be rivalling anything for bulk lifting capacity per dollar (DaVinci carries 400kg; I'm not sure how much SpaceShipOne will carry). Rei 16:05, 12 May 2004 (UTC)
moving stuff from Talk:Space elevator
This stuff seemed more relevant at Talk:Rocket than Talk:Space elevator. I hope you can use it on the main Rocket article. -- DavidCary 10:19, 27 May 2004 (UTC)
Rocketry Capital Costs
- Paul, will you ever stop this? The number you're giving for what might be achievable with rockets does not repay capital costs, it has already been demonstrated, and you have never contested this. Consequently, I find it incredibly irresponsible for you to keep citing "rockets without capital costs" vs. "space elevator with capital costs". Can you not see that this is an unfair comparison? Clearly not, because you keep on doing it every other post. Rei 15:38, 20 May 2004 (UTC)
- Rei, (i) a URL you yourself have given in the article itself says that a rocketry solution of $20000-40000/kg which does repay capital costs is possible; (ii) you have already said (paraphrasing) that hell will freeze over before you will consider this to be true and your POV is noted; (iii) I said "controversially" and "if"; (iv) the first para of this section is anon but not from me - was it from you? (v) you have demonstrated that the Shuttle is expensive, you said you would find out the Ariane figures - you never did so nothing is demonstrated by you about rocketry in general; (vi) I did contest your assertions, but not the ones you make about the Shuttle; (vii) I am trying to work out the economics, if you do not want to enter into the discussion in a positive way please stay away. Paul Beardsell 18:54, 20 May 2004 (UTC)
- 1a) Which URL are you saying? 1b) 20,000-40,000$/kg being "possible" with repayment of capital is nothing even remotely special. 2) Consider *what* to be true? Please, Paul, be more specific when you comment. 4) I wasn't responding to the first para; what I was responding to was *you* continually going off about repaying capital when either A) the shuttle is different from all other rockets in that it doesn't repay capital, or B) The shuttle is not different, and rockets don't repay their capital costs in the same way that virtually all federally funded national infrastructure programs (such as the national highway system) do not. 5) I *offered* to try and contact some people to try and get the Arianne figures, but I stated it would be a lot of work. You never responded on the subject, so I didn't. 6) If you're contesting the assertions, then lets be clear: Are you claiming option 4-A listed above? 7) I *am* entering in the discussion in a positive way in that I am doing my best to stop you from making an unfair comparison to try and unjustly smear the concept of a space elevator. Rei 19:21, 20 May 2004 (UTC)
- (1a) You do not read what you cite? (1b) It is not only "not remotely special" (Rei, today); it is "impossible" (Rei, on countless former occasions) - now you have changed your position you can have no objection to me now editing the page accordingly; (2) hey, are you being deliberately difficult? that (i) is true, obviously, need I quote you? (3) there is no 3; (4) are you saying capital costs are not important? (5) so you agree that you did not demonstrate anything about rocketry in general; (6) That the shuttle was an economic disaster seems to be your point; how all the rest follows from that is difficult to see; (7) Evidently you are not. Paul Beardsell 19:32, 20 May 2004 (UTC)
- 1a) For God's sake, Paul, I've cited several dozen things. If you're not going to tell me what thing that I've cited that you're referring to, please stop talking about it. 1b) WHAT ON EARTH ARE YOU TALKING ABOUT? You've never told me what you're saying that I said was impossible! This is *INCREDIBLY* annoying!!! 2) No, I am *NOT*. You've been incredibly vague, and I have no idea what even the general subject you're referring to is. How am I supposed to know what "you have already said (paraphrasing) that hell will freeze over before you will consider this to be true" when you don't say what the "this" is??? 4) I'm saying, for the (insert very large number here)th time, if rockets don't repay capital costs, you can't have the elevator repay them in a comparison, or it is unfair. 5&6) What on earth are you talking about? There are two options, and I will repeat them: either A) the shuttle is different from all other rockets in that it doesn't repay capital, or B) The shuttle is not different, and rockets don't repay their capital costs in the same way that virtually all federally funded national infrastructure programs (such as the national highway system) do not. Take your pick. Rei 20:17, 20 May 2004 (UTC)
- In response to your recent change of #6: They've all been economic disasters. That's what rockets are. The shuttle is a common punching bag mainly because it claimed to be able to do so much better, but turned out to be more of the same. Rei 20:17, 20 May 2004 (UTC)
- 1a) OK, how about looking at the very first URL cited in the Economics section of the article - the one next to the very point we have just been editing. (1b) you have been saying (and I will quote you if necessary) that capital costs cannot be recuperated out of the $20,000/kg lifted figure. (2) I am sure it is plain to other readers, and that is all I care about. (4) Here we go again! See -1b-. (5&6) See -2- but you want me to answer another "have you stopped beating my wife" question: I like neither of the alternatives you present me with. (7) Evidently your attitude remains unchanged. Paul Beardsell 20:38, 20 May 2004 (UTC)
I have placed an NPOV marker back in the Economics section. I wish to compare speculative future rocketry costs with the speculative future costs of a SE. Paul Beardsell 20:38, 20 May 2004 (UTC)
- 1a) Thank you. Now, given (1b) (see next sentence), how does this URL help your case? 1b) Using current rockets, you cannot recoup capital costs out of the 10,000-40,000$/kg range to LEO - correct. 2) 5&6) For God's sake, Paul, then what alternative DO you accept? I'm trying to get you to adopt a position here instead of "you're just wrong, but I'm not going to say why". How can I get you yo answer this? Hmm, lets try this - a series of questions:
- A) Do you accept that the space shuttle does not repay its capital costs?
- B) Do you think that rockets apart from the space shuttle - such as Ariane - do repay their capital costs?
- C) If your answer to A and B are both "Yes", then: Why would you expect (B) given (A)?
- I've been trying to get you to address this for a long time, and you keep refusing to. It's been ticking me off. Rei 20:51, 20 May 2004 (UTC)
- The supposed logical fallacy of which you accuse me does not even need to be evaluated: Once again! I never said the words you put in my mouth: I never expected B given A. Just because a Ford is a waste of money doesn't make a Chevvy one. It is you who say this, not me: You have been criticising the whole of rocketry because the Shuttle was a lemon, using Shuttle figures. The other scattergun attacks you make at me are typical of your argumentative style, to be polite. Paul Beardsell 21:10, 20 May 2004 (UTC)
- No, No, No! I'm not going to let you dodge this again. ANSWER THE QUESTIONS. If you think C is a fallacy, at least answer A and B, and I will replace C with two questions to make it clearer:
- C) Why do you believe (B)? Do you have a shred of evidence to support it?
- D) Why is (A) not clear evidence against (B)?
Outdent. This is a dishonest way to argue. You present me with a list of questions as if they comprehensively address the issue at hand. As if they are even the fairest questions to answer. They are asked in such a way as to somehow suggest that I have taken particular positions which I have not. (c) You are currently addressing the Ariane costs in the next section. Let's see. (d) Let's apply your argument to non-space matters: There are several Reis. One is a Wikipedian. Therefore the others are. No. You are using induction, not deduction. Paul Beardsell 21:32, 20 May 2004 (UTC)
Ariane
I think I found a way to prove that Ariane, at least currently, has not even come close to repaying its capital costs, without trying to get in touch with some people who have the raw numbers. Ariane's development capital costs were about 8 billion dollars (over 7 billion euros, not counting the recent bailout that they did) spread over 10 years. It has had 18 launches (3 of which were failures, but that's beside the point). Its payload to LEO is 16,000 kg (it usually goes to GTO, for which its payload is only 6,400 kg, but that's beside the point). That's almost 28,000$ per launch in capital costs alone. Consequently, it has not come close to repaying its capital costs at all, even if the rocket launch was free. Now I've proven that the shuttle doesn't repay its capital costs, and that the Ariane at the very least hasn't (and likely doesn't) - what more do I need to do to convince you? Rei 20:51, 20 May 2004 (UTC)
Actually, that's a good point, that I didn't even think of. We're comparing costs to LEO. The elevator goes to GEO. I'll go factor that into the article.... Rei 20:51, 20 May 2004 (UTC)
- But the $25,000 Ariane figure is to either GTO or GEO not LEO. And don't forget that the next improvement to Ariane doubles the payload! Paul Beardsell 21:02, 20 May 2004 (UTC)
- ... and raises the launch cost. Come on, Paul, you think they're just going to rip off a piece of the rocket and say, "There we go, it carries more now!"?
- Doubtless. But that doesn't mean the overall cost per kg is not decreased. Paul Beardsell 21:44, 20 May 2004 (UTC)
- Ariane carries about 16,000kg to LEO and about 6,400kg to GTO. I was kind and assumed LEO in the calculations above; if you assume GTO, you over 80,000$ in capital costs per launch, making it even more ludicruous. Rei 21:18, 20 May 2004 (UTC)
- I'm lost over the 80k but note the $25k is for much better than LEO, which is what you have recently tried to insert into the article itself. Paul Beardsell 21:44, 20 May 2004 (UTC)
You must quote your sources so we can see what the "development capital cost" includes. Also, Ariane's life is not over - there may be another 18 launches (=$14,000/kg "devt capital costs) or, for all I know, even a total of 72 (=$7,000/kg "devt capital costs"). How much does a rocket actually cost to build (the marginal cost of just one more rocket - i.e. without "development capital costs")? When we know that then we can divide that by the payload and add the cost of the fuel ($100 per lifted kg or thereabouts) and total that with the "devt capital costs". If(please note!) the figure is less than $25,000 we have Ariane repaying all costs if there are 72 launches. Paul Beardsell 21:02, 20 May 2004 (UTC)
- You can get the development capital costs from Wikipedia, and these numbers can be confirmed in many places (for example, the FLTP article on Astronautix [2] says that its upper-end cost of 16 b$ for development is twice that of what Ariane took to develop. ). Sorry, I can't say specifically as to what is included in this, but it's clearly development costs. You never give up on this, do you? Why on earth are you so insistant that Ariane is repaying its capital cost? Name a single piece of evidence you've provided that suggests that.
- I am not. Once again you are ...... ..... .... .. ..... You are insisting there is no capital repayment. The opening sentence of this section says what you are trying to do. By refusing to fairly consider the evidence, I suggest. I simply want it argued. Whenever I make a good point you boil over. Paul Beardsell 21:38, 20 May 2004 (UTC)
- I mean, give me a break. Do you think the 8 billion dollars included the building of all 18 rockets launched? Do you actually believe that? Please tell me that you're not that dumb. Here's a suggestion: Before you touch the economics section again, how about youfind a shred of evidence to support your stance.'. How does that sound? Rei 21:18, 20 May 2004 (UTC)
- Once again you are ...... ..... .... .. ..... I never said that. I said take the capital cost (when we know what they are), divide by the payload, add the cost of one more rocket divided by the payload, add the fuel divided by the payload, then we have the cost of one more kilogram - all costs included. I think you do not want the calculation done: I think you fear the result will contradict your prejudice. Paul Beardsell 21:38, 20 May 2004 (UTC)
Assume 72 launches, divide into $8bn. Divide by 16000kg payload to GTO or say 8000kg to GEO. $12196/kg devt capital cost per kg. Now, the additional cost of one rocket is say $100m (and that is a guess!) including fuel. That's another $12000/kg. That's a total of less than $25000/kg to GEO, capital costs included. But what is the cost of one more rocket? Paul Beardsell 22:05, 20 May 2004 (UTC)
- No, I'm not going to let you get away with any of this nonsense again. I'm not going to debate someone who refuses to respond to my questions. Otherwise, I'm just speaking to a wall. 1) I demand a shred of evidence if you are to assert that claim again. I've presented several pieces of evidence that suggest that it's not true (the shuttle's lack of repayment, and the fact that the repayment schedule would have to be incredibly long). It is 2:0. I refuse to let this go on without you making it at least 2:1. Even if you personally don't like my 2, your zero is simply unacceptable.
mislocated
- Again, I don't care if you think they're not fair. I want answers:
- A) Do you accept that the space shuttle does not repay its capital costs?
- B) Do you think that rockets apart from the space shuttle - such as Ariane - do repay
- C) Why do you believe (B)? Do you have a shred of evidence to support it?
- D) Why is (A) not clear evidence against (B)?
- I never said that this "comprehensively addresses the issue at hand". These, however, ARE major problems with your argument, and you do refuse to answer them. I want answers.
- I have dealt with this already. Paul Beardsell 22:28, 20 May 2004 (UTC)
- Lastly, I'm sure you're not stupid. "There are several Reis. One is a Wikipedian. Therefore the others are." Oh, please. That would be reasonable if I were saying "Since the Ariane is a rocket, it should be edible." I'm not arguing over different things with the same name. I'm arguing over things that are all rockets. Rei 22:12, 20 May 2004 (UTC)
It's Logic 101. You are inferring that because the Shuttle was an economic disaster that all rockets must have the same problem. I said that was the same as saying that there are several Reis, one of them is a Wikipedian, therefore they all are. No. In both cases this is induction not deduction. Paul Beardsell 15:16, 21 May 2004 (UTC)
- The shuttle is no more of an economic disaster than every other rocket! Paul, wake up and look at the launch costs!!!! They all cost a fortune, the shuttle is no different. Ariane is a disaster, too - they just had to give it a big bailout. Do you think they'd be giving it a big bailout if it was "repaying capital costs"? No, they'd just stop repaying capital costs. They all are economic disasters, because rocketry is *Hard* - something you refuse to accept. Rei 16:49, 21 May 2004 (UTC)
"Assume 72 launches, divide into $8bn. Divide by 16000kg payload to GTO or say 8000kg to GEO. "
Wrong. The Ariane-5 has 6,200 kg to GTO payload. If we want to call GEO half of that, that's 3,100kg. That's about 35,000$ for the 72 launches. Try again. By the way, at the current launch rate (18 launches from 1996 to 2004 - 8 years), that would take 32 years to repay.
They're not repaying. Deal. Rei 22:12, 20 May 2004 (UTC)
- Depends on the cost of one Ariane V. Paul Beardsell 02:42, 21 May 2004 (UTC)
I think you do not want the calculation done: I think you fear the result will contradict your prejudice. Paul Beardsell 22:30, 20 May 2004 (UTC)
You can prove anything by assuming it first. Paul Beardsell 22:28, 20 May 2004 (UTC)
The next rockets are 12800 not 16000 kg payload, my mistake. But according to the source you quote, Wikipedia, the devt cost is $7bn, not $8bn, your mistake. We will redo the calc to find I was out by 10%. Paul Beardsell 22:28, 20 May 2004 (UTC)
At 32 years perhaps we would have it repaid before the necessary material science techniques have been developed for the SE. But if we increase the rocket launch rates some costs will be reduced. The SE needs, it seems 2,000,000 kg lifted to get to a reasonable cost / kg. That's 312 Ariane launches. Paul Beardsell 22:28, 20 May 2004 (UTC)
- The "next rockets" will cost more, too - this has already been covered several times. FoWhat, do you think they're just going to rip off a piece of the side of the rocket and say, "There, done!"? For God's sake, Psb, the "it's going to carry more in the future" line of argument is just plain idiotic. It's going to carry more because they're adding the ESC-B upper stage. You think that's free?
- FoWhat, you think they gonna doit at extra cost jus' for the hellovit, missy? Paul Beardsell 02:42, 21 May 2004 (UTC)
- The cost is 7 billion *euros*. A euro is worth more than a dollar. YOUR mistake.
- OK but maybe: The euro did not even exist when the Ariane was developed. What with currency movements in the interim it is difficult to determine the USD costs. But, what the heck, so I am 20% out. As I said, the $100million was a guess. You're the one with the access to hidden facts: How much is one Ariane V?
- At 32 years, you would be repaying it if we charged 35,000$ per kilogram more than the base geosync cost. Please, go on, tell me that Ariane costs a lot of negative money to get into geosync. Rei 22:53, 20 May 2004 (UTC)
- I can recognise the unmistakable sneer in your post but that's as far as I get. Paul Beardsell 02:42, 21 May 2004 (UTC)
This is all just diversionary tactics away from the main argument. You just don't want the comparison done. And I do not know if it repays all the capital devt cost or not. But I would like to know from the facts rather than just take it on your say so. Paul Beardsell 02:42, 21 May 2004 (UTC)
- Ok, lets just let it be known officially: Paul has refused to answer my questions. He has refused to back up his assertion, which he keeps on making. Consequently, Paul is refusing to discuss. Consequently, he should not be allowed to edit in this dispute. I'll repeat them, in case you ever feel like rejoining the discussion, Paul:
- A) Do you accept that the space shuttle does not repay its capital costs?
- B) Do you think that rockets apart from the space shuttle - such as Ariane - do repay
- C) Why do you believe (B)? Do you have a shred of evidence to support it?
- D) Why is (A) not clear evidence against (B)?
- I'll add one more:
- E) If Ariane was repaying its launch costs, why would it have had to have a major bailout recently? Wouldn't they just stop repaying capital costs?
- lastly, as mentioned earlier....
- 1) I demand a shred of evidence if you are to assert that claim again. I've presented several pieces of evidence that suggest that it's not true (the shuttle's lack of repayment, and the fact that the repayment schedule would have to be incredibly long). It is 2:0. I refuse to let this go on without you making it at least 2:1. Even if you personally don't like my 2, your zero is simply unacceptable.
- P.S.: "Preparatory work began in 1984. Full scale development began in 1988 and cost $ 8 billion." [4]
- P.P.S.: The page has changed since then, but look at this google cache: [5]. Notice at the bottom: "... of the Ariane 5 contracting team have agreed to reduce their costs to permit Arianespace to assemble, fuel and launch an Ariane 5 rocket for 136 million euros." Drive another stake in your mistaken notion. NO CAPITAL COSTS. "Assemble, Fuel, and Launch". Rei 16:49, 21 May 2004 (UTC)
Rei continues to say I have said things I have not. She is repetitively and dishonestly doing so. Paul Beardsell 17:51, 21 May 2004 (UTC)
Prices
Wolfkeeper has brought up a couple new systems that haven't been discussed yet.
Soyuz: Let's pick on in the series at random - say, Soyuz FG. Launch cost 50m$, payload 7420 to 51.8 degree inclination. Price in 1994 dollars=50m$, Prince in 2004 dollars~=70m$. Just under 10k$/kg.
"Chinese": assumedly he means "Long March": Lets pick a random one; the CZ-4A. What do we find? 30 million dollars in 1994 -> ~45 million now, 4,680kg payload... just under 10k$/kg again.
Ones he mentioned that were already discussed:
"Sea Launch" - Assumedly he means the never built Sea Dragon, whose design proved to be not only overly optimistic, but an outright failure, when a smaller version was built as SEALAR. Or he could mean a number of other things...
- No I mean sealaunch. Hey, here's an idea, why don't you use google? You know- research? I even included a reference to a data source that gave it's launch costs... (If your google is broken (funny how Rei's google is always broken when it comes to cheap conventional rocketry), Sea Launch is a Boeing/Russian joint effort- with *seriously* cheap rockets...) Wolfkeeper
- Sorry, we were discussing the Sea Dragon earlier here, which was a never-built rocket that Truax claimed could get spectacular returns. "Sea Launch" is often used as a generic term; you should have stated Zenit-3SL with a Block DM-SL to get to GEO, instead of citing the company - "Sea Launch" is not a rocket. Lets look at the geostationary transfer orbit so we don't have to factor the Block in... the Zenit-3SL itself costs over 100m$ in current dollars (90m$ in 1999), and has 5,250kg payload. That's almost 20,000$/kg to geosync transfer [6]. Even if you assume that you can get twice as much to LEO, that's still not cheap. Rei 20:48, 25 May 2004 (UTC)
- I did cite Zenit-3SL you removed that from the article! It's not my fault if you don't known what launch vehicle Sea Launch use! Actually, a LOX/Kero stage like the third stage of Zenit-3SL the appropriate multiplier is 3x, giving a price to LEO of ~$6600/kg, even with your more pessimistic figures. Most other vehicles use hydrogen which is more efficent, and then 2.5x is more like it.--Wolfkeeper 00:39, 27 May 2004 (UTC)
- I didn't remove a thing from the article - check the history. I don't like the accusations, either. Care to back up your LEO claim? Rei 16:13, 27 May 2004 (UTC)
- Sure, no problem. Go to [7] where it lists the delta v to go from LEO to GEO as 3800m/s. Then take the rocket equation: deltaV = exhaustVelocity * ln(InitialMass/finalMass). Exhaust velocity for LOX/Kero is about 3500m/s in space situations. Solve the equation and you get an initialMass/finalMass ratio of 3. i.e. 2/3 of your mass to LEO is fuel used to get to GEO. The rest is payload and rocket engines and so forth. Unlike launch situations, zero-g rocket engines provide very low thrust and are usually exceedingly low mass; so to a first approximation (within a few percent) can be neglected. Feel free to compare this with actual launch vehicles figures. In some ways this calculation is pessimisic- it assumes you go to LEO, and then go to GEO; it's more efficient to launch straight into GTO and add a circularising burn into GEO. Also, if you are going to LEO you may need one less stage which reduces costs further. Wolfkeeper--81.174.170.32 17:34, 30 May 2004 (UTC)
Wolf, if you'd read the talk page (I know, it's monstrous, and has lots of fighting!), you'd be familiar with the fact that launch costs have remained relatively stagnant since the 1960s,
- They were cheaper in the 60s due to high production rate of icbms. They are cheaper now because the encumbents are actually having to reduce costs- there hasn't been that pressure before.Wolfkeeper
- Once again, more uninformed speculation. Care to provide a reference, Mr. References? Rei 16:13, 27 May 2004 (UTC)
- Most rockets were not based on ICBMs. Rei 20:48, 25 May 2004 (UTC)
- Wrongo. In the 60s most *were* based on ICBMs
- Well, lets see... what were the workhorse rockets of the US back in the 60s? Off hand, I'd say the Titan and Saturn series. The Titan used in the space agency was based on an ICBM for the lower two stages, with non-ICBM upper stages added (such as the Titan Transstage, the Agena D, the Centaur D/E, etc). The Saturn series was unrelated to ICBMs for all of its stages. That's one which has some ICBM stages (but not others), and one completely unrelated.
- Precisely my point. The Saturn was 2 or more times more expensive, because it didn't have the economies of scale of ICBMs.
- This is "most"?
- Yeah. Definitely most of the cheap ones anyway; I can't be bothered to count them by launches, but I expect ICBMs launches were certainly more numerous. Don't forget Mercury used Atlas.
- Oh, I forgot, we need the Atlas series also. It works out the same as the Titan (ICBM lower stages, non-ICBM upper stages. Rei 16:13, 27 May 2004 (UTC)
- Yup. Atlas was fairly cheap too. p.s. Mercury used Atlas for launching; quite a few Mercury launches.
and that while NASA is working on reducing costs to 25% of their current level, it's been a slow program that is way behind schedule. Rei 00:09, 25 May 2004 (UTC)
- I wasn't aware that there was a schedule. The main reason that the price is flat is due to perceived price inelasticity in the market. The encumbents can reduce prices, but if they do they make less money (noteably the Ruskies; Ariane and the American launchers are only partly commercial and use cost-plus contracts and other political perversions- and yeah Ariane nearly went bankrupt a while back and got bailed out which makes it even more complicated to work out what went on.) Wolfkeeper
- Laf, you don't think SLI has a schedule? Amusing. :)
- No, they have a schedule. And they had one last year, and the year before. None of them are remotely the same.--Wolfkeeper 00:39, 27 May 2004 (UTC)
- Please explain how, with a 500-600m$ launch cost, the shuttle is repaying its capital costs.
- You're so last year. They've just got an accountant as their head honcho- and he's insisted that their accounts make sense. The price per Shuttle launch is now officially nearer $2 billion!!!!--Wolfkeeper 00:39, 27 May 2004 (UTC)
- NASA, before the shuttle disaster, has been averaging 5-6 shuttle launches per year [8].
- See: [9] "_$15.2 billion over the next decade or so to add a fifth shuttle flight to the annual schedule. The shuttle has been limited by budget constraints to four flights a year and nearly all have been dedicated to assembly of the space station. The added flight could be used to accelerate station assembly or to perform other missions that are not now possible." That's 1.5 billion per flight, per year.
- The shuttle's budget is usually around 3 billion dollars [10].
- That depends on precisely what parts of NASA you ascribe to the Shuttle. If you quite reasonably count some of the other bits of NASA my understanding is that it is nearer 6 billion dollars per year; and the latest accountancy figures reputedly suggest that to be the case.
- Get a grip on yourself
- Alright; call it 1.5 billion per flight.
- - 2 billion dollars a launch would be almost NASA's entire budget.
- Actually NASAs yearly budget is more like 15 billion, and they don't usually launch 6 times a year. Check out: http://groups.google.com/groups?q=constant+dollars+budget+nasa&hl=en&lr=&ie=UTF-8&as_drrb=b&as_mind=12&as_minm=5&as_miny=2000&as_maxd=30&as_maxm=5&as_maxy=2004&selm=9ad41526.0307161413.6820d53c%40posting.google.com&rnum=2
- Why do you keep making claims on things you know nothing about?
- I don't :-) p.s. I don't know why you're complaining, you're the one always trying to make launchers expensive. :-)
- Rei 16:13, 27 May 2004 (UTC)
- Please explain how, given the cited cost to build, fuel, and launch an Ariane rocket, they're repaying capital costs. Also, when you do such a comparison, try and determine the amount of time it would take to pay back the system. For example, if Ariane makes 2,000$ per kilogram to geostationary transfer, then, in the 18 launches in 6 years (ignoring the fact that 3 of them were failures), they would have only repaid 200 million of their 8 billion dollar cost. Rei 20:48, 25 May 2004 (UTC)
- Arianespace went bankrupt and got bailed out. Big deal.--Wolfkeeper 00:39, 27 May 2004 (UTC)
NASA is working to reduce costs to 1/4 of what? I want to put the figure in: I saw a figure somewhere that NASA's target was $1500/kg. That target may have now been abandoned but presumably they must have once thought this realistic - I mean: It was a target stated as policy. The SE is not a stated policy target yet the article takes the SE very seriously, I think it should take a stated policy target from NASA also very seriously. It is the aim of the Economics section to compare the speculative SE with the speculative costs of future rocketry, is it not? Paul Beardsell 20:31, 26 May 2004 (UTC)
- I had a page on NASA that discussed it in more detail before, but I can't locate it any more. Looking for it, though, I ran into an Aviation Now article discussing how SLI funding has been partially shifted to building a lifeboat for the ISS [11].I really wish NASA would get more information on their SLI website and clean it up; it's a big collection of dead-links and scattered pages.
- Hmm... this isn't encouraging: [12]. I never heard about this, but an earlier NASA study determined "The basic structure of the SLI (program orientation, objectives, schedule, technology) renders the program impossible for successful completion. The elements are so obviously lacking in credibility as to discourage best efforts by either government or industry." Rei 21:11, 26 May 2004 (UTC)