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Post Info TOPIC: Let the Space Shuttle Fly!
john fraz


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Another "opinion"...
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Griffin Seeks to Break Shuttle Blockade of Moon-Mars Exploration
October 18, 2005

Reports from Washington indicate that NASA Administrator Dr. Mike Griffin has been holding discussions with the White House to seek approval for a policy that would truncate the Shuttle program and rapidly shift its funds towards implementation of human Moon-Mars exploration.

This is exactly the right policy. The Mars Society supports such a shift 100 percent.

The only Shuttle mission worth flying is Hubble repair, a mission of extraordinary importance for which the Shuttle has been specifically designed and for which it is uniquely capable. In contrast, using the Shuttle to engage in Space Station construction while a Moon-Mars heavy lift vehicle (HLV) is in the offing is a grotesque waste of the taxpayers' money. Once we have an HLV, we will be able to launch in a day what the Shuttle can launch in a year – in its best years; three years at currently projected launch rates; or eighteen years at current actual launch rates. Furthermore, by delaying heavy lift development to engage in pointless Shuttle missions, NASA would place the entire Moon-Mars initiative at risk, both because after Katrina there may not be enough money to sustain both Shuttle and Moon-Mars, and in any case, administrations will change in 2009. Unless the authors of the new space Vision show enough faith in it to get it going in earnest while they are in office, it will almost certainly be thrown by the boards by the next administration.

The right policy is this;
1.      No more Shuttle missions except Hubble repair.
2.      Shift Shuttle funds immediately to accelerate development of HLV, CEV, and Moon-Mars technology.
3.      Set the goal, and go for it: Moon by 2012, Mars by 2016.

For seeking to open the Shuttle blockade, Griffin has come under attack by advocates of waste and stagnation. But the choice before NASA is clear: Either we seize the day to break out into the solar system, or we consign ourselves to another generation stuck in low Earth orbit.

Mike Griffin has made his choice. Now it is up to you to make yours.

Thirty years of stagnation in space is enough.

Call or write your senators, congressmen, and the President today.
Tell them you support all efforts to shift from the Shuttle program to human Moon-Mars exploration as quickly as possible. All congressmen and Senators can be reached through the Capitol switchboard at 202-224-3121.

If you want to see a human future in space, it is time to speak up.
Call today.

For further information about the Mars Society, visit our website at
www.marssociety.org.

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"A devotee of Truth may not do anything in deference to convention. He must always hold himself open to correction, and whenever he discovers himself to be wrong he must confess it at all costs and atone for it." Monhandas K. Gandhi
John


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RE: Let the Space Shuttle Fly!
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Well, at least I can now see what you with this extreme anti-shuttle theme.  I'm not saying that the shuttle was the best way to go back in the early 70s.  It seem to me that we were push to far with too little budget.  However, in 2006 the shuttle is an accomplished fact and it is supported by all those much hated greedy constituencies.  Dr. Griffen may well kill the shuttle but we can be very sure that he won't get us to Mars by 2016!


It seems to me that the course that is being suggested is much like what we did in 1960s.  We raced to the moon and then just stopped.   Even if we to a moon mission and a Mars mission with capsules and throw away rockets once its done the next administration most likely stops it just like Apollo. 


What we need is a sustained presence in space such as the ISS and the shuttle flawed though they are.  The practical problem is that why we should be developing a next-generation shuttle the technology is not ripe do to decades of neglect.  We should have hypersonic RPV by now to demonstrate scram jet techonology instead we only have the X-43 10 second wonder.  Surely we can come up with something better than glued on tiles for heat shielding!


My concern is that if we change course too fast we will not be setting the stage to develop an advanced SSTO shuttle that could accomplish the original goals set for the shuttle.  Economical access to LEO is the basis for any sustained interplanetary program.  The next thing we need is advanced orbit-to-orbit propulsion technology such as VASIMR.  Then Mars would be in reach in as little as four months.


The CEV should be designed to be able to be used for Moon missions but primarily though of as an augment to the shuttle and a vehicle to transport crews to the ISS and as an emergency rescue vehicle.  After it is developed funds should go to the shuttle 2 project.   Once access to orbit is cheap and VASIMR is perfected we could be in position to push for a Mars project.  We need to find way and reasons to get more money into space projects including private and foreign funds.



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john fraz


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further advancements
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The way things go, I despair of seeing any sensible advancements on new launch vehicle technology. Anything really new they try is going to take 15+ years and tens or hundreds of billions to R&D, and it'll almost certainly have a lot of graft built into it (as any long government program will).


The best recent development I saw was a few years ago during the office of the Space Launch Initiative (SLI) working towards their Orbital Space Plane (the older OSP, then the entire office died or was severely cut back when the Bush space plan came into being).


 Northrup/Grumman's proposal, as I've said, was a lot like the HL-42.  A reusable, survivable, cheap to operate spaceplane, with no radical advancements needed, and a lot of OTS parts (as the HL-20/42 designs were). Like the HL-42, it could go to a runway landing from the top of the booster on the launch pad or any stage of the launch! One variant used a flyback first stage booster (unmanned), which was nothing new really. The core 1.5 stage (parallel burning) was expendable. The upper stage was small, since it was only the final boost to orbit, and contained the escape rockets on the tail skirt of the plane (a good place to use a hybrid for either upper/circularization, or the escape rocket, in one package).


This was an evolutionary step up from the baseline HL-42, which just used typical rockets based on ICBMs like the Atlas or Arianne V or such. Nothing about this was really new, expect the concept, which was to put the crew in a small spaceplane which had nothing but a lot of ways to let the crew survive just about anything (built-in forgiveness). The same booster arrangement, without the OSP on top, put up about 25 tons, which replaced the Shuttle's capacity with far less cost. There was no way this could cost as much to develop as a "Whiz-Bang" all new technology beast like the VentureStar, and while it wasn't as sexy as a "Next Gen" or "Shuttle II" or some thing with a linear or SCRamjet, it was readily acheivable and superbly useful. AFAIC, sacrifice a little payload and put a jet engine on it, for flyback/approach/go-around or self-ferrying and the early flight tests. Looking at it, it's got nothing too far out, so maybe it's not too exciting, but the capabilities it would give us are unprecedented in anything else close to coming off the drawing boards, or anything we've got now.


Typical that it fell by the wayside, and all we've got now is a capsule, which seems to be another bastard hybrid of arbritary requirements, and they seem to be resisting the simple expedient of the Shuttle-C for HLV duty.


> Economical access to LEO is the basis for any sustained interplanetary program.


You said a mouthful there, brother! That's part of why I push for immediate development of the Shuttle-C, since there's absolutely nothing new about it, except a dumb, unmanned, non-reusable cargo shroud! Multiples of the Shuttles cargo, for a fraction of the cost per launch vehicle stack on the pad, and per launch -how can we lose? Sure, it's a step backwards to simplicity and expendables, instead of a new technology wonder or continuing to "Stay The Course" and flying the Shuttle we've got... But the capability is the point!


hmmm... I see there's no compilation of links and debate points for the Shuttle-C around here. My next project.


Of course, for "economical access to LEO" (without being dependent on radically new technologies), I really like the Sea Dragon. All kinds of good sense in that concept, but it's too unfamiliar, and the political graft machine is too set in its ways to accept it.



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"A devotee of Truth may not do anything in deference to convention. He must always hold himself open to correction, and whenever he discovers himself to be wrong he must confess it at all costs and atone for it." Monhandas K. Gandhi
10kBq Jaro


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RE: Let the Space Shuttle Fly!
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In the May/June 1999 issue of the Journal of the British Interplanetary Society there is an article with a description of a CEV-type launcher with some modifications for re-use, by Carl A Carrouche (Phoenix USA):


"A recoverable Orbital Launch Vehicle is proposed configured along the lines of a commercially successful, expendible launch vehicle. The reusable lower stage is composed of a single, Space Shuttle SRB. The upper stage is propelled by a single SSME and attains orbit with a 50,000lb payload. The upper stage is further developed in such a way so it can easily be configured into a reentry vehicle whilst in orbit. Having survived reentry but while still high in the atmosphere, the vehcle then divides into two serparte components. Taking full advantage of serendipity, it is discovered that both components are naturally shaped in such a way so that each part is capable of surviving the impact of landing upon the ocean's surface, thus solving the paramount problem of reusability."


The reconfiguration in orbit is carried out by astronauts working on a "reconfiguration beam" equipped with a robotic arm, to assist in docking. Carrouche concludes that "The skills and techniques learned in the erection of [the ISS] are all we need to make us competent to effect the reconfiguration of a RLV in orbit."


Quite an interesting concept, that could make good use of existing hardware, if found to be feasible....

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John


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NASA while not going with the Shuttle-C concept literally are doing something similiar with the HLV that is derived from Shuttle and other off the shelf components.  That will provided much what is being called for here.  You would get reusability in the SRBs that way.  Could we also recover the liquid fueled first stage?


The idea of recovering the orbiting stage is iteresting but it would seem to require a large orbital space capability to implement.  Most upper stages wouldn't be that close to the space station and so we would need a special craft and astronaut team to set up the boosters for reentry. 


The issue is do we go for the Moon mission like has been proposed and abandon the Shuttle to pay for it or do we delay the Moon part of it and have a Shuttle plus CEV capability.  The CEV would be used for crew transfers between the ISS and ground. Also, it would constitue a rescue capability if  a shuttle would have that falling ice problem again (<1% chance per mission).  Return to the Moon would await a larger budget. (Which I'm all for but Congress most likely will not agree.) 


For the longer term what we need is the new technology.  The has been a major advance in fly space propulsion since the 1960s.  I've seen Buzz Aldrin's plan for Mars using existing propulsion.  My thought is that actually developing a nuclear electric power source and a VASIMR engine would be a lot better use of our money (and cheaper) that a direct push to Mars right now.  We could test and use the VASIMR on the ISS (based on solar power and subscale) and then develop a prototype of the nuclear electric power source plus VASIMR for unmanned outer planetary missions.  Then with the techology in had we could push for a full-scale version for manned Mars.


On LEO I still think an one stage space plane with scram-jets/rocket multimode engines is the way to go and worth the billions it would take to develop.  This would work well for mid-sized payloads like the shuttle.  We do need a HLV to put up the big stuff.  There has been a test flight of a hypersonic device that runs on jet fuel and achieved mach 5.5.  Perhaps some of the required technology could come from military programs.  I still think that LH2 will be the fuel for the Earth to orbit vehicle.


One key thing is to find more practical near term applications for operations on orbital platforms.  If there is money to be made in it that support for it will follow.


 


 


 



-- Edited by John at 16:29, 2006-03-26

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GoogleNaut


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I think that some of a shuttle derived heavy launch vehicle can be made to be reusable: as you point out, the SRB's are inherently reusable. By designing a vehicle with an engine pod that also has a reentry heat shield, and with a RCS capability, then it should be relatively easy to splash one down and then recover it for engine refurbishment. The question that must be asked is whether the cost savings of refurbishing the engines is worth the additional complexity and cost of a recovery option.

I'm not entirely certain how to answer that. A shuttle derived heavy launch vehicle that, conceptually, I was looking at had 8 SSME's, and the equivalent of 4 Shuttle OMS pods. The engine pod was huge and would be complex and quite expensive. If the cost of refurbishing each SSME is about 1/6 of the replacement cost at about $30 million each, then for an 8 engine cluster, refurbishing the SSME's would be about 30/6*8=$40 million, whereas the cost of replacing all 8 would be closer to $240 million, all other things being equal.

Now the way things look, it may be much cheaper to look at a vehicle that uses say a cluster of 4-6 RS-68 engines that cost about $6-7 million each which gives an engine cost of between $24-42 million. Using them only once isn't that big of a deal, compared to the payload the could be delivered. However, if one adopts a philosophy that the propellant tank and the engine thrust structure (as well as the engines) are a part of a deliverable payload, then this will add many thousands of pounds to payload already delivered to orbit, in each flight.

What is needed is a larger orbital faclility where things like tanks, engines, and structural parts can be disassembled, cut apart, sorted, and recycled. This requires a big fascility, probably a pressurized hanger, lots of onboard power, and of course, a fairly large crew. But it can be done...


As far as having dual capability with both Shuttle and CEV flying, I don't see it happening unless NASA suddenly gets a much larger appropriations alottment from Congress. And then, it kind of makes more sense to put the money into a Second Generation Shuttle, perhaps something like a Two Stage To Orbit vehicle. Because the current system which uses the ET as it now is designed, will always have the danger of foam strikes. The only way to prevent them is to eliminate the foam, and then ice strikes will be an even bigger danger. So an inline vehicle makes more sense....


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john fraz


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RE: Let the Shuttle-C Fly!
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Far better for an unmanned Suttle-derived HLV to go with expendable engines. No more pushing of the state of the art than necessary, and to put ~80 tons up in one shot, you don't need to recover the second stage engines ("form follows function" and KISS: "keep it simple, stupid"). Don't use expensive SSMEs, when any number of other engines will work.
I'll bet it would be cheaper overall to meet it in LEO with a CEV; If it's at the Station, then they need to put a robot arm and EVA prep & support at the station ASAP. Put big cargo loads and crews up vastly cheaper than the Golden Goose shuttle.

What's particularly appeaaling about the Shuttle-C is that everything we use now is still used. Nothing new needs to be developed. From the factories and plans that make the components to the transport infrastructure that gets it all to the Cape, to the VAB and the crawlers to the fixed service structure and the rotating service arm on the pad, all the way to the flame trenches that were specifically designed for the off-center engines of the side-stacked Shuttle orbiter.
Any other HLV we try, then not ony the R&D of the thing itself, but all the infrastructure that launches it needs to be paid for.
For the Shuttle-C, all we need is a dumb unmanned non-reusable cargo shroud...

Cut the Shuttle orbiter (except the HST repair flights) to divert funds to the CEV so we have a manned launcher by 2010. Streamline the development of the shuttle-C so within 3-5 years, we have an option for a larger presence at the ISS (single pressure vessels or the same small modules, or large structures like trusses). That gives us practise for operating the 2 types of launchers for a while to allow confidence in designing the Lunar plan.

Anything like a new technology Shuttle-2 or the dreamed-for 2STO HTOHL is ten$ or hundred$ of billion$ away. Yeah, it'd be nice to see some attention paid to it, but for efficiency and safety (not just crew safety, but the entire space program) we need something as a workhorse for now and the near future. While we're flying the CEV and Shuttle-C the next several years, instead of our HTO 2STO dream, I'd rather see development of the Shuttle-Z; the big, inline 120 tons to LEO SHLV. Yeh, it's not as sexy as what we'd like to see, but it could be done within 10 years and it'd get us to the Moon and Mars. When that's a going concern, we'll be able to R&D our dream ships, but for now and the next 10 or so years, what are we going to use? (without hemmoraging money away with the Flying Cost-Overrun Golden Goose. Too expensive to operate and too little capable of doing anything we need -except diverting massive amounts of tax dollars to the contractors -the one thing it's good at.)

This image shows the crudity it could utilize. Nothing fancy, nothing that's not needed to perform the mission. (Realistically, the engines and payload would be integrated on a thrust structure to mimic the Orbiter's attachment to the ET)


http://www.astronautix.com/lvs/hear2008.htm

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"A devotee of Truth may not do anything in deference to convention. He must always hold himself open to correction, and whenever he discovers himself to be wrong he must confess it at all costs and atone for it." Monhandas K. Gandhi
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