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NASA's Space Launch Initiative will be massively downgraded (the funds will most likely be diverted to the station and shuttle upgrades) and there is talk about the military getting involved in the development of a new RLV. Then there have been numerous mentions of a so called CTV (crew transfer vehicle) in the past two or three months, on nasawatch.com and elsewhere. What is this CTV? Then there is the X-38/CRV. Looks as if O'Keefe wants to have this program axed at all cost for whatever reason. Link
I'm really a bit confused right now. Where is NASA heading? I just hope Europe sticks to its plans to develop the Hopper.
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The CTV is a concept that is backed primarily by Orbital Sciences. It's a more luxurious version of the autere X-38. In fact, The OSC concept is based on the HL-20 lifting body. Such a CTV could act as a crew capsule or a rescue vehicle, and it could be launched by either a reusable rocket or an expendable EELV.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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Yup.
I was thinking about what NASA, the USAF, and commercial partners would want out of SLI. It dawned upon me that SLI should not be a single vehicle, but a modular family of vehicles, all similar in concept to a shuttle orbiter with flyback boosters and ET.
In one configuration, a small orbiter with expendable hydrogen tanks is boosted by a reusable, winged rocket and then rockets into orbit. Ths would be great for small satellites. Larger orbiters (using the same engines and subsystems) and larger hydrogen tanks could be mated to this flyback boosteror a cluster of flyback boosters. In the ultimate configuration, a Heavy Lift Launch Vehicle orbiter is mated on top of a large hydrogen tank with several flyback boosters clustered around.
This concept borrows liberally from Buzz Aldrin's Starbooster, but it's a good idea.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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I like the idea of making the next workhorse launcher a modular design. They should definately make it possible to lift heavy, unmanned payloads into orbit using the same boosters but with different carriers, one for manned and others just for payloads. It's a little like the Shuttle-C concept. It would certainly make it easier for projects like missions to Mars.
To achieve the impossible you must attempt the absurd
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Very interesting news (from nasawatch.com):
"Last weekend NASA Administrator Sean O'Keefe and much of NASA HQ senior management went on a retreat at the Minnowbrook Conference Center at Syracuse University. Among the topics discussed: NASA's Integrated Space Transportation Plan (ISTP).
The road ahead? The U.S. is now heading towards a 100% home-grown successor to America's Space Shuttle and alternative to Russia's Soyuz.
For the past several years, NASA's generalized concept for a follow-on to the Space Shuttle has been a smaller vehicle specifically designed to transport humans to and from orbit. Only minimal cargo carrying capability would be provided. This vehicle has gone under the general name/acronym of "CTV" (Crew Transport Vehicle).
Current planning at NASA HQ has now focused and recast the role of the CTV. In its deliberations on re-toolling the ISTP, NASA HQ now refers to it as the "Orbital Space Plane." The current concept favored by NASA HQ involves launching the Orbital Space Plane aboard an EELV (Delta IV and/or Atlas V) rocket. Moreover, this is not just a way to take people to and from orbit, it is also the means whereby they could be removed from the ISS (on short notice) in an emergency. As such, the term "CRV" (Crew Return Vehicle) is used less often these days. There is also little mention of long-term usage of Soyuz "Interim" CRVs beyond current arrangements with Russia.
The Space Shuttle figures very prominently in NASA's future plans - with its life likely to reach well into the next decade with development of advanced 'third' generation reusable launch systems to slip into the future. This focus on Shuttle operations will require increased spending on making the Shuttle system not only safer but more reliable and more economical to operate. These modifications have been referred to as Shuttle "upgrades" in recent years.
Given the somewhat more expansive span of Shuttle modifications anticipated, NASA HQ is now referring to them as Shuttle "enhancements". Also under discussion: increased Shuttle flight rates [excellent idea] and the possible future flight of Space Shuttle vehicles - unpiloted. [What does that mean? Do they want to revive Shuttle C?]Also: look for X-37 orbital tests.
Meanwhile, to set the course for these major changes, modifications to the current FY 2003 Budget request (and future years) are being developed by NASA for forwarding to OMB. If implemented, these changes would result in dramatically decreasing funding for SLI. A substantial portion (billions) of the Space Launch Initiative's $5 billion will be spent in the coming years on other programs such as the Orbital Space Plane and Shuttle "enhancements".
SLI will be reduced to a program of advanced technology demonstration - not one of launch system development as previously envisioned."
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I don't think it necessarily mean Shuttle-C. I'm not sure exactly why they'd want to fly the Shuttle unpiloted either - maybe it's worth doing at the end of its life when we have something better, I suppose. However, I find the concept to be very intriguing; the Buran was flown perfectly unpiloted, and it just goes to show what's possible.
Editor of [url=http://www.newmars.com]New Mars[/url]
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If the shuttle were ever used for launching commercial satellites, it would have to fly in an unpiloted mode (astronauts would be unnecessary in the situation and represent an added expense.) It's good to see that SLI might end up enhancing the shuttle for increased flight rates (such as advanced, health-monitoring engines and flyback boosters.)
But I'm disappointed that NASA would return to the paradigm of "artillery as spacecraft." Being able to launch a spaceplane on an EELV in an emergency is a plus, but it is too expensive to continue on a regular basis.
The more I think about SLI, the more skeptical I become. From a technology standpoint it was good, but Space Frontier and Pro Space were right about one thing: it's leading us down the continued path of goverment-controlled spaceflight and "business as usual."
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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The ideal would be a single stage to orbit (SSTO) reusable launch vehicle (RLV) that uses a rocket based combined cycle (RBCC) engine. An RBCC engine would operate as a RAM jet, a SCRAM jet, an air augmented rocket, and a rocket engine that uses LOX as oxidiser. This hypothetical space plane could horizontal take-off, horizontal land (HTHO). The NASA view for third generation vehicle is to use a magnetic catapult to launch the vehicle to the speed required to ignite the RAM jet. If we are going to dream, the vehicle could have a small fan jet engine added for take-off. It would only require enough thrust to lift the vehicle off the ground and accelerate to speed necessary to start the RAM jet. You could even duct fan jet exhaust into the RBCC intake so it would act as an after burner for added thrust to accelerate to RAM jet ignition speed. A fan jet could be used for powered landing; you could "windmill" the engine to air restart it upon approach to the airport. If the fan jet used the same fuel as the RBCC engine, it wouldn't require a separate fuel tank. Addition of a fan jet would increase safety, and permit the vehicle to take-off and land from any commercial airport equipped with fuel handling facilities. Unfortunately, there is no RBCC engine available.
Now back to reality. If you can launch 95 tonnes to the ISS with Shuttle-C for the same cost as 19 tonnes using the current Space Shuttle, then why not? If you can ferry astronauts to ISS on an X38 derived vehicle using Delta IV or Atlas V for $170 million per launch instead of $545.5 million for a Shuttle launch, then why not? It's just economics.
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Economically, launcing astronauts by EELV would be cheapest (but check your figures--the CTV would need a heavy EELV, costing about 3x as much as a standard Delta IV). But the point I'm making is that we deserve better than the throwaway boosters of the past. Aviation Week & Space Technology reported that NASA considers RLV launch of the CTV as a future option, but I think it's an idea whose time has come.
I believe that we don't have an RLV at this point because there is no commercially viable reason to build one. And because the EELVs have been completed, the U.S. launch market has been cornered. If the Air Force had wanted several reusable launchers instead of a single family of expendable rockets, we'd still be waiting, but we'd eventually get that commercial RLV. Once we can get this commercial RLV, the earth-orbit frontier will open up to "the rest of us."
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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Launching an aerospace plane on an EELV might not be so bad as a transition to the next stage of technology. If it brings launch costs down by a factor of three, maybe it would open the tourist market. Let's say seven people can be put in orbit for $170 million; that's $24 million each. Maybe demand at that price will grow somewhat and help wedge open the tourist market, which has the potential to improve safety and cut costs. If the shuttle is retired and replaced by something that is a third as expensive, that will help make the ISS viable and speed the day when the moon or Mars can be considered.
-- RobS
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I'm under the impression that EELV launch will only be an interim option. The first Orbital Spaceplane flight will be an unmanned mission to the ISS, delivering the long-overdue lifeboat. The OSP will be unmanned and there will be no need to man-rate the EELV. Eventually an RLV would launch the OSP. The RLV might be an Air Force Space Ops Vehicle, or it could be a commercially-operated RLV. Either way, its an important step toward routine and commercial use of space.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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check your figures--the CTV would need a heavy EELV, costing about 3x as much as a standard Delta IV
These are the figures for a heavy EELV. Atlas V 401 costs $77 million, Altas V 501 costs $110 million, and Atlas V 551 costs $170 million. Delta IV Medium costs $90 million, Delta IV Large costs $170 million. All costs are per launch in 1999 dollars. Astronautix.com does not list a price for Delta IV Small.
The total cost for Space Shuttle in 2002 according to budget figures reported to congress was $3.2728 billion. Based on 6 launches per year that works out to $545.5 million per launch. The actual orbital altitude of ISS is 220 miles or 354km. Published lift capacity for Space Shuttle on NASA's web site is to 185km, and Astronautix.com lists it to 407km. Interpolating to 354km the result is 19 metric tonnes of cargo.
I had discussed a configuration of Shuttle-C elsewhere, and the engine pod was much lower mass than the orbiter. Each pound of reduced mass means an additional pound of cargo. That results in 95 tonnes to ISS. Notice that is exactly 5 times the mass that the orbiter can lift.
Lift capacity for Delta IV Large to 185km at 28.5? is 25.8t. I interpolate the lift to ISS as 17t. Atlas IV 551 could lift 20.05t to 185km at 28.5?. I interpolate that to 13.2t lift to ISS. The X38 fact sheet says it can carry 7 astronauts, masses 11.3t and the deorbit propulsion system masses 2.7t for a total of 14t. You would have to trim a bit of mass to use Atlas, but Delta is more than enough. You would probably need a fairing around the deorbit module to support the X38 during launch, but that would mass much less than the 3t extra lift offered by Delta IV Large.
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Thanks for the info, Robert.
I like the idea of a shuttle-derived launcher like Shuttle-C, but I think that RS-68 engines should be used instead of the heavier and less-powerful (and less expendable) shuttle main engines. The RS-68 is a marvel of modern engineering and I hope we see it on more rockets than just the Delta IV.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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I shouldn't really be posting here because I find the lengthy descriptions of huge numbers of different rockets with mysterious acronyms give me headaches!
I feel the term 'EELV' is probably a key factor in all this and I keep meaning to do a google search one day to find out what it means! The LV bit must be launch vehicle ... but the EE ... Hmmm.
Easily Elevated?
Extremely Energetic?
Enormously Expensive?
Anyhow, that's not why I'm here. I just came across what is either a very cynical evaluation of America's space program or a painfully accurate description of same!
If you've already read this article, I apologise for bringing up old news. But, if you haven't, you may find it interesting (read depressing! ).
The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down. - Rita Rudner
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I shouldn't really be posting here because I find the lengthy descriptions of huge numbers of different rockets with mysterious acronyms give me headaches!
I feel the term 'EELV' is probably a key factor in all this and I keep meaning to do a google search one day to find out what it means! The LV bit must be launch vehicle ... but the EE ... Hmmm.
Easily Elevated?
Extremely Energetic?
Enormously Expensive?
LOL, I think the last phrase fits perfectly "EELV=Enormously Expensive Lift Vehicle." Reminds of that WWII ship that was abbreviated the SEV. The sailors decoded it as "sinkable expendable vehicle."
To achieve the impossible you must attempt the absurd
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Hi Shaun,
Please don't be disheartened. It may take a little research to get "up to speed" on all the various acronyms, but anyone who really cares can do it quickly. The term LV does in fact refer to Launch Vehicle. HLLV means Heavy Lift Launch Vehicle, such as Saturn V or Ares. EELV is an odd acronym; it means Evolutionary Expendable Launch Vehicle. It refers to the US program to upgrade existing launch vehicles to deliver launch capability competitive with Ariane 5 or Proton. When someone talks about an EELV they are talking about the result of a specific program, not a class of launch vehicle. That is why I never used the term until Mark S brought it up.
When talking about Launch Vehicle classes, definitions have become fuzzy recently. NASA used to categorize Saturn V or the Russian N1 or the proposed Ares launch vehicle as Heavy. The Space Shuttle or Titan 4B or Russian Proton were categorized as Medium. The Russians, however, categorized the Proton and Titan 4B as Heavy, and the Saturn V and N1 as Super-Heavy. Now Boeing wants to categorize Delta IV Large as "heavy" despite the fact it is in the same class as Titan 4B or Proton. The salesmen are having fun at your expense.
The article you quoted does make some good points. The heaviest versions of Atlas V and Delta IV (vehicles developed under the EELV program) have exactly the same price as the European Ariane 5, and comparable lift capacity. Does anyone believe this is a coincidence? By the way, the European Space Agency is in the process of upgrading Ariane 5. Competition lives! Add to that the Russian Angara 5 that will replace Proton, and the Chinese Long March CZ-5 that will have a core based on Europe's Ariane 5, and you have an incredible level of world competition. For those who want commercialization to replace NASA; don't worry, it is already here.
I had worried when the Delta Clipper (also known as DC-X) had worked perfectly when the US Air Force was in control, but the first launch by NASA with participation by Lockheed-Martin resulting in a crash-and-burn. It crashed because someone "accidentally forgot" to remove a pin that preventing one of the landing legs from deploying. The X-33 was mostly based on existing technology used in new ways. The only new technology was a composite cryogenic fuel tank. Lockheed-Martin made a last minute change to the tank design, and the first test resulted in failure. Lockheed-Martin refused to comply by the contract clause that required them to share the cost of that set-back, so the X-33 as cancelled. Then the X-43A (also known as Hyper-X) failed its first test flight. It was supposed to be a scale model of a SCRAM jet aircraft. It was launched on a Pegasus rocket, but that rocket mysteriously had a fin fall off. Then one month after I mentioned to an employee of Orbital Sciences (manufacturer of the Pegasus) that the Russian Energia could be reactivated relatively easily, the Russian vehicle assembly building had its roof collapse. Every possible low-cost replacement for the Space Shuttle has been lost. To those who believe in conspiracy theories, this sounds like industrial sabotage.
I should mention one mistake in that article. It mentions "NASA may soon cancel the promising VARISM plasma engine research project citing a lack of funds." I believe this is referring to the VASIMR engine. That is another acronym; it stands for VAriable Specific Impulse Magneto-plasma dynamic Rocket.
So where does that leave us now? The Atlas V and Delta IV will have to remain competitive with other launch vehicles. Their largest versions have a lift capacity comparable with the cargo bay of the Space Shuttle. Delta IV Large can lift an X38 to ISS. Replacing the Space Shuttle may take 2 launches of Delta IV Large, one for cargo and another for astronauts, but at $170 million per launch compared to $545.5 million for a single launch of Space Shuttle, you tell me which is the better deal.
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What an extraordinarily informative and helpful post!!
Many thanks, Robert, for taking the time and trouble to come back to me on this. You've managed to cram a lot of facts into a very digestible and understandable precis, and I read the whole thing without a single headache coming on!
You may or may not know from other posts I've submitted, that I love a good conspiracy theory. And you've given me an absolute beauty!!
When there's just so much money and so many jobs at stake, you have to wonder at a series of 'coincidences' such as you've outlined above.
As you stated:-
Every possible low-cost replacement for the Space Shuttle has been lost.
Remarkably convenient!
The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down. - Rita Rudner
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The heaviest versions of Atlas V and Delta IV (vehicles developed under the EELV program) have exactly the same price as the European Ariane 5, and comparable lift capacity. Does anyone believe this is a coincidence? By the way, the European Space Agency is in the process of upgrading Ariane 5. Competition lives!
...I had worried when the Delta Clipper (also known as DC-X) had worked perfectly when the US Air Force was in control, but the first launch by NASA with participation by Lockheed-Martin resulting in a crash-and-burn. It crashed because someone "accidentally forgot" to remove a pin that preventing one of the landing legs from deploying. The X-33 was mostly based on existing technology used in new ways. The only new technology was a composite cryogenic fuel tank. Lockheed-Martin made a last minute change to the tank design, and the first test resulted in failure. Lockheed-Martin refused to comply by the contract clause that required them to share the cost of that set-back, so the X-33 as cancelled.
The "heavy" versions of Delta IV and Atlas V, using three common booster cores, go beyond the capabilities of Ariane 5; they were designed to replace the Titan IV, which has approximately the same payload capacity as the Shuttle.
Lockheed Martin had nothing to do with DC-X. The ship was built by McDonnell Douglas. Its further development was killed by Lockheed Martin, but not because of any meddling with the DC-X (the DC-X crash landing occurred after DC-X development was halted.) Basically, NASA stopped funding the DC-X in favor of Lockheed Martin's X-33, which from the point of view of most engineers was inferior from the start. It relied on too many unproven technologies, like complex composite fuel tanks, aerospike engines, and a metallic TPS. Furthermore, the demands of a single-stage to orbit spacecraft left little room for weight growth. When Lockheed Martin tried fabricate the multi-lobed fuel tanks for the X-33, they exploded during testing. McDonnell Douglas had used a simple-shaped composite hydrogen tank on the DC-X and it worked admirably.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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Hi all,
I want to comment on ArianeV, it seems that this launcher is dedicaced almost always to communication satellites, Earth observation satellites, mainly for commercial purposes and for any country willing to pay.
Sometimes, an European Research Organization has just enough money to pay for half a payload and so they send a scientific mission but rarely. That launcher is very competitive but it doesn't seem to be used much for space exporation.
This is in contrast to an Heavy Launch Vehicle, like shuttleC, nicely described by Robert. If a shuttle C is built, this is to do something specifically requiring heavy payload in low orbit, like ISS, but does the ISS even needs such huge payload NOW ? not sure, or it is for Mars. Luckily, I am sure that as time passes, the technology for that HLV will be slowly transfered to private compagnies which will give it a try. There is always hope.
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Ariane 5 was intended for launching communication satellites into geosynchronous Earth orbit. However, its specifications state it can lift 16,000kg to 407km orbit at 51.6?. The specifications for the upgraded Shuttle state it can lift 16,050kg to the same orbit. It looks like Ariane 5 can operate to the ISS.
There have been a lot of arguments about X-33 but the aerospike engine was developed during the 1970s as an option for the original Space Shuttle. Metallic heat shield tiles (thermal protection system or TPS) were developed recently and NASA even replaced a few tiles on Shuttle with metallic ones to test them in space. Metallic tiles work, but don't provide as much heat protection as silica. A spacecraft that uses all metallic tiles must re-enter at a shallower angle. Composite tanks and conformant tanks have been used by the aircraft industry for years, but not for cryogenic fuel. Conformant just means it fits the inside space of the aircraft rather than being spherical or cylindrical.
The tanks were new, but they didn't explode. One was tested by pressurizing with liquid nitrogen (for safety). The problem occurred after the nitrogen was drained and the tank was warmed up; it disintegrated. Analysis after the fact showed the cold caused micro-cracks in the tank wall causing liquid nitrogen to seep in. When the tank was warmed the cracks sealed shut, but with liquid nitrogen inside the cells of the honey comb structure. When the nitrogen boiled to gas, the pressure burst the tiny cells from inside. They should have stuck with the original solid-wall composite design. The upgraded DC-XA did use a composite hydrogen tank using the same material, so it does work.
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I have a more modest suggestion. The question is how to get the powers-that-be to listen.
If the goal is to reduce launch cost, I would suggest a more modest implementation of a Crew Transfer Vehicle (CTV). The X-38 was originally called a Crew Return Vehicle (CRV), but since engineers have been working on ways to launch it on Europe's Ariane 5 or some other rocket, they now prefer the name CTV. The original proposal was for a 4-astronaut vehicle since the Russian Soyuz could carry the other 3. That would permit a fully crewed space station of 7 astronauts. Some American planners did not want to rely on Russian technology, but the Soyuz has proven itself over a third of a century so I say why not? If we return to a 4-astronaut vehicle that would make it much smaller. In fact, such a smaller CTV could be launched on an Atlas V 401. That would reduce launch cost to $77 million instead of $170 million for Delta IV Large. The Russian Soyuz FG launch vehicle is the latest upgrade to carry the Soyuz-TM spacecraft to ISS. It costs $40 million per launch in 1999 dollars. That cost doesn't include the spacecraft or mission control operations, just the launch vehicle. A small Atlas V is still significantly more expensive, but at least it's cheaper than Delta IV Large. A reusable CTV spacecraft may make the cost difference less significant.
That would create an even more cost effective alternative to the Space Shuttle. $170 million for Delta IV Large to carry cargo, plus $77 million to carry 4 astronauts in a CTV, plus whatever the servicing cost would be for the CTV, plus mission control cost. That sounds significantly cheaper than $545.5 million per shuttle launch.
Atlas V 401 is the small configuration of Atlas V. It has a 4 meter diameter fairing, and can lift 12.5t to 185km at 28?. I calculate it should be able to lift 8.25t to ISS. The 7-man configuration for X-38 with its de-orbit module would mass 14t, and Soyuz-TM with its 3-man capacity masses 7.15t, so a 4-man version of CTV should be able to fit within 8.25t.
Perhaps it would be more politically correct to argue for a space station with a 4-astronaut capacity and an all-American CTV. This would be more than the 3-astronaut capacity that some are arguing for now. Scientists complain that it takes 2.5 astronauts just to operate the station, so they are left with half an astronaut to run science experiments. Adding one more astronaut would tripple science, and politicians could still brag that the American spacecraft can carry one more astronaut than the Russian one.
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Hi Robert,
Yes, cost matters of course. But there is also politic. Russians have been pissed off by the story about their tourist cosmonaut being coldly received in the ISS. They also probably feel that, irrespective of the russian or european money and efforts engaged in the iss, the ISS remains in total US control. So why to invest in it ?
Maybe the europeans have plans for an European SS, smaller, like the size of Mir.
Anyway, a small RCV for 4 people would be a useful advance of course, but for Mars, Shuttle C or equivalent is requested.
We need to be clear. NO scientific project needs such a HLV. Only Men to Mars needs that. Here is the problem: sending men to Mars is not scientifically justified. Robots on Mars can do all the science, better cheaper, safer. Sending men to Mars is more about the humanity fate or politic considerations. It's not a scientific absolute request. Now, what's the goal of NASA, science or sending flags to other planets ? It's mixt, 80% science, 20% politic. "Science" doesn't need a HLV to send 100 tons to Mars and 20% politic is not enough to do it either.
But we, at the Mars society, we need something like shuttleC.
In my opinion the solution can partly comes from the private sector when companies realize they can make money with Mars. Maybe we can interest the private sector by sending to Mars light, relatively cheap probes, like gliders, polar cap penetrators etc, to make some sciences but also a lot of "exploration/fun" science like in "discovery channel".
Imagine TV channels broadcasting a glider over Valles Marineris, almost like in "69". In that respect, pathfinder was a success. As the public get more interested, the private funding increases and finally a big constructor decides to build a HLV to send Men there... the big adventure starts.
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Let us not cut our own throat. Science does require humans on Mars. The anorthosite sample that was discovered by Apollo 14 would never have been found by random sampling by robot probes. Evidence of life would be even more rare. Carol Stoker did an experiment where she had several individuals use remotely operated rovers to look for fossils. None of them found any. She didn't tell them where the ROV's were; they were in Dinosaur Park, the densest concentration of dinosaur fossils in North America. Palaeontology requires human eyes and human hands climbing rough terrain and splitting rocks with a hammer.
There are other uses for a HLLV as well. M-Type asteroids are basically big chunks of metal floating in space, mostly iron and nickel but they also contain precious metals. C-Type and D-Type asteroids contain carbon and water. Iron and carbon make steel, add nickel and other asteroid metals like molybdenum and vanadium and you have excellent stainless steel. Water can be split into hydrogen and oxygen, great for rocket fuel. Commercially mining asteroids, however, requires heavy equipment and that requires a cost-effective HLLV.
Then there is the Moon. Many Mars enthusiasts see the Moon as competition, and the Moon does lack some resources necessary for a completely self-sufficient colony; but the far side of the Moon is the ideal location for space telescopes. Constructing a Moon base would also need a HLLV.
Currently, there have been many cut-backs to ISS in an attempt to reduce cost. Shuttle-C could carry 5 loads of equipment at once. If it is launched within hours of the Shuttle Orbiter, then the Orbiter could use its arm to grab the cargo and position it close to ISS where the station's arm could put components in place. That is, 2 launches (Shuttle-C and Shuttle Orbiter) configured as a single mission could replace 6 Shuttle launches. To avoid aerodynamic problems, Shuttle-C would have to carry dense components, such as truss segments, solar panels, radiators, or a module packed full of equipment. This would permit previously cancelled modules to be restored.
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We do have uses for an HLLV besides humans-to-moon or humans-to-Mars. Space Telescopes and space lasers, some of the heaviest payloads we can think of, could benefit from a Shuttle-C or shuttle-derived rocket. I'm sure that science will dream of even heavier payloads once the booster is built.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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