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http://www.thespacereview.com/article/146/1]The Space Review (Jeff Foust article)
uh-oh... why did i post this here.
um, yea, to get some comments where or if it is wrong (the article)
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The article admits that HLLVs have cost less per pound than smaller vehicles. HLLVs also get more value per pound than large manned applications. Therefore, HLLVs are a good idea. I don't know if they need to be as large as Saturn V, but the EELVs just aren't big enough.
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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.
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it would be easy for a future Administration or Congress to terminate the program and leave virtually nothing left of government manned spaceflight.
Yes, that one also really jumped out for me... It's really weak. What does he suppose instead that is *not* easily 'scrappable?' In fact, i don't even see *any* logic in this kind of reasoning...
And the idea of 'gladly' accepting one out of 3 payloads with an unreliable but cheap booster, that's indeed DUMB. No-one would go for that, there is no such thing as *really* cheap payload, and blowing up 1 in three launches would be bad for safety on the ground (not to mention possible pollution) but no-one will accept such a hightened risk of getting yet *more* debris in LEO.
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Some day in-space construction and decent RLVs will get good enough, but some sort of heavy-er launch vehicle then whats available today is a must for any sort of beyond-LEO work except small scale science missions.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Yeah, i thought those points were weak too, but he is right when he says that a nasa-contracted HLLV should be designed to fit mission criteria and not the other way around.
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Buuut it takes more fuel to put a rocket into a minimum velocity/minimum altitude eliptical orbit than a circular one. Hence, it would NOT be cheaper in any shape form or fasion.
Cracking ice to make rocket fuel also simply isn't very practical at the moment, nor is atmospheric skimming currently practical either without getting more drag than push from fuel.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Ballistically, straight up, with no change of direction above the atmosphere must be the cheapest way to launch. If the resulting orbit misses the atmosphere on its way back, how could that not be cheapest. Yes or no?
What the use of such an orbit might be put to, is problematic, but that wasn't my purpose (to justify its usefulness) but rather to suggest an alternative affordable means of accessing microgravity and the vacuum of space for extended periods of time, by commercial interests.
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Unfortunatly it still takes considerable energy to "miss" the Earth on the way back down, especially since Earth's gravity is going to fight to make you bulls-eye our heavy little sphere. You might as well put the thing into a circular orbit.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Unfortunatly it still takes considerable energy to "miss" the Earth on the way back down, especially since Earth's gravity is going to fight to make you bulls-eye our heavy little sphere. You might as well put the thing into a circular orbit.
I have to admit that you're right, of course, regarding circular orbit. But, for economy's sake, launching from the equator, during an eclipse of the Sun, straight up: to a distance which matches in time to return from apogee with the radius of Earth in order to "miss" the Earth . . . no additional energy other than what is needed to reach that height would be involved. Comparison of the amount of LOX/LH2 for this hypothetical orbit and that used to reach LEO might provide an interesting benchmark. If it turns out to be sufficiently better (I hope some kind soul will calculate this for me to save time) the solar eclipse may not be necessary, and the thrust angle lowered from 90-degrees beyond the atmosphere to obtain an optimumally economic launch. Having got it of my system, I'll think I'll quit whipping this dead horse of an idea and get back down to Earth (oops) suggestions.
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I thought that the most on-point comment in the article was that we have excess launch capacity that would work just fine for launching cargo, and we should use it.
If we're going to design and build any new vehicle - especially on the tight budget Bush has planned - let's put the effort into making a safe but reasonably inexpensive human launch/return system.
For safety, it should have a single high reliability engine per stage. Ideally it should be a single stage, so if it can launch, it'll probably make it to orbit. Inefficient, but safer - less to inspect, less to go wrong, and some of the things that can go wrong won't be as disastrous (e.g. if the one engine doesn't fire).
There should be safe abort options throughout 100% of the flight - from boarding through landing. Launch little more than crew and plenty of air in a capsule designed to handle re-entry. It needs an emergency rocket eject system, and perhaps that can double as a back-up de-orbiting system - just enough to bring them down into thicker atmosphere where their orbit will eventually decay, if they have no other options.
Fly everything else ahead of time and check it out on orbit before the humans lift off - even the rocket needed to do a normal de-orbit. Have a spare de-orbit rocket standing by to launch if needed.
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For safety, it should have a single high reliability engine per stage.
This means there's no engine-out contingency. So you're pretty much screwed when that engine does fail; unless you have an escape tower, or some other stage can quickly take over.
Ideally it should be a single stage
Unfortunately there's little advantage in an expendable SSTO. In fact the mass ratios involved make it pretty bad idea. For any given mass or cost a multi stage rocket could lift more.
ANTIcarrot
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How much would it cost to develop something from the current shuttle
ie how much for shuttles c-z and the Ares
Nasa has just spent billions to get the Shuttle safer, Why waste it.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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How safe & reliable spacecraft are is all about probability, and what risk is acceptable for the system. Since no system can be entirely risk-free, "100% safe" is not a reasonable goal, and the more safety/reliability required of a given system tends to increase price and decrease performance geometricly (see Space Shuttle).
For a manned rocket with the safety of the crew as the #1 issue, you are faced with somthing of a tradeoff, making a rocket with a small number of reliable engines and counting on them not to fail or a rocket with a large number of engines where the chance of one failing are high but an engine-out is not as dangerous. The latter would seem to be preferable, but with the higher risk of engine-out, you also increase the risk of engine explosion or fuel fire, not to mention a very large increase in complexity and expense fundimental with multiple engines.
An SSTO vehicle is probably not going to happen under PlanBush (save maybe the crazy Thiokol idea of putting CEV ontop of a single Shuttle SRB) which leaves us with staged rockets. We already have two such vehicles built here domesticly, the Delta-IV and Atlas-V, which are powerd by a single first stage engine (RS-68, RD-180) and either one or two proven second stage engines (RL-10 varients). Older rockets from Boeing (Delta) and Lockheed/Martin (Atlas) have proven to be aproximatly reliable enough (aprox 99% reliable) and should be safe enough with the addition of a crew escape system.
Unfortunatly, both Delta and Atlas were intended to carry medium to large sized satellites and not heavier space capsules, so whatever form the CEV takes it must be kept fairly light to be able to reach the ISS 51deg orbit. Making the escape system motors do double-duty as emergency OMS engines isn't practical, because the escape motors have to be solid fueled for quick startup and able to generate 6-8G's of acceleration, entirely opposit of what an OMS engine requires.
Overall, it is a little questionable if a good CEV can ride on these Medium rockets, and will almost certainly require the addition of small SRBs to boost capacity, and may even require the extreme option - using the Delta-IV Heavy with its three first stage engines and two upper stage engines, although its possible it won't be any less reliable than the Medium rockets with a pair of small SRBs.
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As for the price-tag of the Shuttle-C, the most likly Shuttle-Derived vehicle to be built (and what Nasa's Mars Design Reference Mission is based on) has been quoted in the past to be $1-5Bn depending on modifications, but now is probably around $10Bn.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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As for the price-tag of the Shuttle-C, the most likly Shuttle-Derived vehicle to be built (and what Nasa's Mars Design Reference Mission is based on) has been quoted in the past to be $1-5Bn depending on modifications, but now is probably around $10Bn.
Any idea what those costs reflect? Conversion, construction, launch or all three? If all of the above, what launch rate? Using anything derived from the shuttle means incuring the wrath of the dreaded Fixed Maintinance Cost of looking after all the shuttle facilities. That makes it very difficult to estimate the true value of any shuttle C programme.
ANTIcarrot.
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The problem that the shuttle as it stands is it is a very poor cargo carrier.
The shuttles poor launch rate means it is not accrue any advantage from machine line endeavours. It has from an engineering standpoint a very bad design ethic, Why send so much mass to orbit to have it come back down again?
Frankly it also suffers from the cost plus methodology of the current Nasa way of operating. The shuttles maximum delivery to orbit of cargo is 24400 kg, this can be compared to other launch systems and is found wanting.
The shuttle c though has the potential to be a true heavy lift option, It benefits from the amount of research that has been done on the previous shuttle and can use the same facilities. It uses the SRB's which after the challenger explosion have become the most investigated item of rocket technology since the V2. The Shuttle c only returns to earth the expensive reusable engines and lends itself to being pilotless saving more cargo room.
Saying that the shuttle c is not the same as a new saturn 5
The shuttle c does face some hurdles, Unless the cost plus system is removed the devolopment time will be long and increased fees accrued. It will to be most efficient need another means to deliver People to orbit(maybe one of the x prize contestants). But these can be hurdled and costs to orbit could be reduced something the original shuttle was supposed to do and failed
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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It still means rebuilding of infrastructure that the Russians' done have and which we already do... if Boeing would be willing to sell the RS-68 for $10M a copy I don't think the price of bringing the Russians in on this is worthwhile, especially considering the expense in political capital over the Iran mess or rebuilding parts of Russian space infrastructure & jobs with US taxpayer dollars, and at such a price then developing a engine reentry pod makes dubious financial sense if equipped with SSMEs.
The RS-68 is more powerful than either the SSME or the RD-0120 in any event by around 50%, so if Shuttle-C were originally intended to have a trio of SSMEs, then it is possible to get away with only a pair of 68's, giving you fewer engines to fail and the engines will be brand new on every flight, increasing reliability. Even at the current price of ~$15M each, $30M for engines is not too bad for a vehicle able to lift three or four times what the $200M Delta-IV HLV can haul (and even more savings over orbital assembly).
It is important I think to take the time to make a clear break from Shuttle and not be concerned with commonality to save a buck today on development; Shuttle-C will not be Shuttle, and should have as few of its failings and inefficencies as possible, so in a way it WILL be re-inventing the wheel, and this will be a good thing, a more efficent and less expensive vehicle will surely result.
The STS system as a means of launch, by and large, has been a miserable failure... while expendable rockets, the children of which are the EELVs of today, have proven themselves time and time again. The reuseable engine pod idea was cooked up to save the super-expensive SSMEs and for no other reason, and making such a scheme would be difficult... heat shield, tank disconnect system, RCS, parachutes, a host of other issues, and then you need to pay to refurbish them... plus add extra weight and extra complexity and more ways for the system to fail. Just use expendable off-the-shelf rockets for goodness sakes.
GCNRevenger, you are making excellent sense to me.
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A few questions - - If the shuttle B/C used a pair of RS-68 engines would you favor inline rather than offset placement;
and
Would you favor a modular approach to allow either a cargo pod carried alongside the external tank or an upper stage atop the external tank?
Would it be difficult to engineer an external tank that could be adapted to either role?
This would seem to give flexibility as shuttle B could be an evolutionary step towards Ares or bigger and NASA could fly whichever version was more suited to a given mission, yet retain as much commonality as possible.
Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]
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At the moment, where it looks like a small scale Lunar program followed by Nasa's "DRM-IV" or similar compromise Mars arcitecture between the ultra-bare-boned MarsDirect and the massive SEI Battlestar Galactica, there isn't any need for a massive 120MT version of the SDV, a 90-100MT launch vehicle would probably do just fine.
So, my money is on side-mounting a combination engine pod/payload faring, ditching the "phantom shuttle" payload bay, OMS engines, and its trappings for a pair of RS-68 engines and a pair of small circularization motors of some sort. Oh, and use the new 5-segment SRBs of course.
As for making a SDV vehicle able to accomodate both arrangements, I don't think that is going to happen. It would make the main tank heavier or force Nasa to maintain capability for two different models, and would add complexity to the VAB/Crawler/Pad39.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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GCN Revernger is dead wrong re. RD-0120.
Robert Dyck is being quite mild when he describes Mr. Revengers remarks on the subject as "political spin". I think rabid xenophobic nationalism is more to the point. Revenger makes excellent use of Big Lie technique by constanly promoting the false assumption that utilization of any technology not developed or currently produced in the U.S. automatically means extra cost to the American taxpayer.
The opposite is true. The ESA, RKA, JSA, CSA etc. all have budgets. The full utiliztion of as many funding sources as possible is the best way to spread the burden. The RKA, along with these other agencies, has repeatedly stated it is open to possible participation in an International Mars Progamme. Paticipation means contributing resources to a partnership, not selling stuff to a dictator.
Cheers.
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Hey, being called a lying, conspiring, decietful xenophobe already? Of course signing your post with "Cheers" makes it all a-o-k.
What ESA/RSA/etc budgets? In fact, except for the ESA, the rest of them may as well be zero as far as a major Mars mission is concerned compared to Nasa's budget and what the mission will cost (no matter who does it).
"The RKA, along with these other agencies, has repeatedly stated it is open to possible participation in an International Mars Progamme. Paticipation means contributing resources to a partnership..." And i'll leave out the "evil amerikan imperialst dictatorship" comment
And the Russians will spend the millions of dollars to revive the RD-0120 program and build dozens of expensive engines with their own money? ...Launching tourists to pay for Soyuz flights, getting bailed out by NASA for ISS hardware (which Russia promised - for free), inability to maintain launch facilities (Energia VAB colapse)...
I see no reason why essentially all the cost for a Mars mission will not fall on the American taxpayers and a little from Europe, save for some misc. bits and pieces. So, since the money for the Mars mission will be coming mostly from America, my earlier comments about the cost of available RS-68 engines versus paying to rebuild the Russian RD-0120 program/production I think are valid. Not to mention, fewer bigger engines means fewer to fail and less complexity.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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There is a lot to be offered by various countries; international participation adds many strengths, not just money. For example, the Mars Direct mission plan is only one option; it is greatly expounded by the Mars Society since the author is our illustrious founder. However, a smaller and more inexpensive option does exist, although it requires a lot of creative thought. A couple weeks ago I attended the Lunar & Planetary Mining Science Symposium. Michael Duke pointed out that we could go to the Moon without any heavy lift if we start with small unmanned missions to deliver In-Situ Resource Utilization equipment first to manufacture propellant. Yes, I got to talk to the man and had dinner with him, his wife, and a few others. A student of his, Brad Blair, presented a paper on space economics and the benefit of ISRU. My question was how do we get all that ISRU equipment into space without heavy lift. He answered but Mike Duke followed with a paper on propellant production and reusability, and he started his presentation by addressing my question: we don't need heavy lift. The upper stages of medium lift vehicles can be reused for trans-lunar travel, and propellant extracted from the Moon and stored both on the lunar surface and Earth orbit reduces the launch vehicle to the size of a Mercury Atlas. I would qualify that by replacing the Mercury launch vehicle with a modern one: Atlas V 401 or Delta IV Medium. The point I would like to make here is that this requires sophisticated robotics. This mission plan requires small, unmanned equipment to land on the Moon, harvest resources, extract propellant, store it in a surface fuel depot, refill a rocket stage and launch it off the surface of the Moon, enter Earth orbit, rendezvous with a spent stage used as a fuel depot in Earth orbit, and transfer fuel while in orbit. All that requires sophisticated robotics. Canada is the world leader in space robotics. You may discount Canada's space contribution, but Canada specializes in developing small but highly sophisticated space equipment that isn't available anywhere else. Canada isn't interested in building the big iron, so don't expect a large launch vehicle. However, ISRU equipment is right up Canada's ally. Would anyone care to speculate how this mission model could be applied to Mars?
By the way, GNCRevenger, are you trying to say that making money by launching space tourists is a bad thing? Commercialization and profit are bad?
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if Boeing would be willing to sell the RS-68 for $10M a copy
That's a big IF. Kay I ask your souce?
Good news if true. There are plans for an ET derived SSTO. With three RS-68s and 20tons of cargo it would have a deltaV of approaching 9,000mps - which should be enough to reach orbit. At $10M/engine and a rather generous $30M for the tank, you get a a launch cost of $3000/kg, which compares quite favorably with many US launchers in that weight class.
With a big IF the RS-68 performs as advertised. NB: This crude maths isn't intended to reflect a design, but show what good news such a engine peice would be - if true.
ANTIcarrot.
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if Boeing would be willing to sell the RS-68 for $10M a copy
That's a big IF. Kay I ask your souce?
Good news if true. There are plans for an ET derived SSTO. With three RS-68s and 20tons of cargo it would have a deltaV of approaching 9,000mps - which should be enough to reach orbit. At $10M/engine and a rather generous $30M for the tank, you get a a launch cost of $3000/kg, which compares quite favorably with many US launchers in that weight class.
With a big IF the RS-68 performs as advertised. NB: This crude maths isn't intended to reflect a design, but show what good news such a engine peice would be - if true.
ANTIcarrot.
This http://www.orbit6.com/crisf/text/shc_tom.htm]site outlines shuttle C costs.
Eliminate SSME (add RS-68) from both the rosy and skeptical equations and per flight costs come way down.
Add SRBs for $60M to $80M and how much additional payload do you get? Larger payloads allow fixed costs to be amortized over more mass.
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Anyway, since Zenit-2 is $1500 per pound, and since Russian technology is not inherently superior (probably the reverse) I am not surprised that ant-Carrot can do a rough calculation and design a plausible American launch system at roughly $1500 per pound.
Edit: Somewhere I read a quip that NASA believes their rocket scientists are essentially watchmakers while Russia believes their rocket scientists are essentially plumbers.
With a watchmaker mentality and government approved cost plus contracts NONE of the US areospace contractors have any desire to lower launch costs.
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Edit #2: Looking at the above and thinking that a $1500 per pound US heavy lift system could be deployed IF ONLY WE WANTED TO makes me think that any variant of PlanBush based on exclusive use of EELV is actually intended to slow down our access to space, not hurry it up.
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Edit #3
Thiokol SRBs have 99.5%+ reliability, right? 112 shuttle flights with 2 SRBs per flight. 1 failure out of 224 SRBs fired with crew at risk and cold weather was to blame.
Okay, how much does 1 SRB cost? Add an LH2 upper stage and launch SeaLaunch style by a 100% private operation off of a converted oil rig perhaps in interantional waters.
No NASA, no standing army. Do it 100% private sector style with minimal overhead.
How much would it cost? How much could it lift?
Could it lift a dry TransHab (fully assembled, just with minimal atmosphere and NO water) - - that stuff comes up on a 2nd launch.
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Good news if true. There are plans for an ET derived SSTO. With three RS-68s and 20tons of cargo it would have a deltaV of approaching 9,000mps - which should be enough to reach orbit. At $10M/engine and a rather generous $30M for the tank, you get a a launch cost of $3000/kg, which compares quite favorably with many US launchers in that weight class.
Bad news even if true.
Fully fuelled, the ET mass is 1,655,000 lbs; the RS-68 mass is 14,560 lbs, so three weigh in at 43,680; 20 tons of payload is 40,000 lbs of course; then allow 80,000 lbs for thrust platform engines/OT, structural stenthening of ET to take thrust and loadbearing, payload shroud and platform, turbopumps, piping, telemetry and control systems, etc., etc. So gross vehicle mass at launch is 1,818,660 --- say 1,820,000 lbs. RS-68 100% thrust at sea level is 650,000 lbf, so three deliver 1,950,000 lbf. Thus the thrust to weight ratio of vehicle at launch would be 107%.
Your vehicle is going to spend so much time (and propellant) fighting gravity as it struggles for maybe a minute or so just to clear the launch tower as it accelerates at a snail-like 2 feet 3 inches per sec/sec, it's never going to come close to making it into orbit.
Now why do you suppose the Shuttle has SRBs?
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I ve made analysis for reusable transportation system:
(If you want to get down below 1500$/kg)
1: we have to take in account development price of course so scramjet technology are out of range to achieve this goal
2: SSTO even with hydrogen engine (almost mandatory) are out of this objective: cost, maintenability, risk
3: on market issue we have to be in the 7/8 t range in low orbit with modularity.
4: to man it all the time like shuttle it too costly (addedweight, risk)
To conclude: What is achievable is a two/three stage launcher using high density fuel:
Two stage mean for example launch by a plane or having a liitle powder/hybrid low cost last stage for orbit injection for ummanned mission or a compact liftting body instead to have 3/6 people send in orbit.The non reusable part have to be minimised so not on the first (and necessarly heavy) stage(s).
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