The SLS: too expensive for exploration? SLS: Слишком дорого для разведки?

Автор Valerij, 11.02.2014 19:43:46

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Valerij

   
Это старая статья, но я хочу начать с нее.
    
ЦитироватьThe SLS: too expensive for exploration?
 by John Strickland Monday, November 28, 2011
   
Цитироватьhttp://www.thespacereview.com/archive/1979a.jpg
Many members of the space community have spoken out strongly against NASA's plans to develop the Space Launch System (SLS), disparagingly called the "Senate Launch System" by some and the "Franken-Rocket" by others. It should be noted for fairness that, to a large degree, this wrong design has been forced on NASA by a Congress bent on keeping current space jobs in their current locations. Most of the reasons currently debated for opposing the SLS are short-term, such as single-source contract legalities, but there are even more important long-term reasons. There are several reasons why I conclude that the SLS is unaffordable for its main intended purpose of landing crews and building bases on the Moon and Mars and that its continued development and implementation will probably be catastrophic for NASA and the human spaceflight program.

The expensive SLS

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The SLS would initially consist of an expendable core vehicle and two five-segment solid boosters that could orbit 70 tons. Refurbishing the solids after each use will cost about 80% of the cost of a new solid booster. A later version of the SLS is slated to use lighter, filament-wound solid boosters that would not be reused, making the entire vehicle expendable. The very large expendable core stage is based in part on the Space Shuttle's expendable external tank, but this new stage would be a complete, monolithic, and very expensive rocket stage, which, along with all of its expensive engines, which would be destroyed after each launch as it impacts into the ocean. The upper stage (used only on the 130-ton version of the SLS) would use a variant of the Saturn 5's upper stage J-2 engines and would usually be sent into solar orbit after a launch and also not re-used. If the SLS design logic is the reuse of "existing" shuttle parts, why is the SLS projected to cost so much more and take so much more time to develop than private alternatives?

The crucial fiscal issues for the SLS are the development costs, the cost per launch (not including the payload), and the annual operational costs. The high cost of each launch (refurbishment or replacement of the solid boosters, replacing the core stage and sometimes the upper stage, pad and launch operations, and the prorated costs of refurbishing and maintaining the old Apollo-era launch facilities to operate the system) will add up. They will ensure that, just as during the shuttle era, annual operational costs will be very high. These costs will continuously sap money fr om the NASA budget that is desperately needed for new technology that could actually advance our ability to operate in space.

One estimate of individual SLS launch costs (not including the payload) can be obtained fr om private launch cost projections, which are now about ten times lower than the current prices for government-sponsored launchers like the Delta 4 Heavy, which are actually increasing due to reduced launch rates. If the projected cost for the Falcon Heavy is about $850–1,000 per pound, or $100 million per 53-ton launch, for about four launches a year, then the cost per pound for an SLS payload would be about ten times higher at $8,500 to $10,000 per pound to low Earth orbit (LEO). This would equate to about $1.3 billion for the 70-ton payload version and $2.45 billion for the 130-ton version. Projected launch costs for the proposed Falcon Super Heavy (150 tons to LEO) are about $300 million, giving cost per pound that are comparable to the Falcon Heavy or still about ten times cheaper per pound than existing costs or projected SLS costs. Some estimates for the SLS test launch costs are as much as 25 times more per pound ($25,000 per pound) than those for the Falcon Heavy. These estimates are based primarily on the development costs. If we include a typical government payload, the cost per mission (vehicle costs, operational launch costs and payload costs) approaches $5 billion or more per launch. It is thus probable that the cost of each SLS launch with payload will be much more than the cost of a shuttle launch, which recent calculations have shown to be about $1.5 billion apiece. The Shuttle did recover the "upper stage" (the Shuttle itself) with all of its expensive rocket engines.

In this discussion, the most important fiscal issue is annual operational costs. We assume that the annual NASA budget allocations will force an upper limit of these costs to an amount comparable to the shuttle's average annual cost of about $5 billion a year. Some estimates place total costs of the SLS system as high as $63 billion through the year 2025, which assumes an average annual cost of $4.5 billion including both the developmental and operational periods. As a general rule, government program costs usually increase over time.

The high individual launch costs will prevent frequent launches of the SLS, and will especially lim it the number of times it can be launched successively in a period of a year or two. One report shows an astonishingly slow projected launch rate of once a year, but based on a comparison of the annual budget available and the estimated individual launch cost, the rate is not surprising. This assumes that the payload (crew-carrying spacecraft, etc.) has a cost comparable to the booster rocket. The combined cost of booster and payload for a single launch would thus probably use up all of the manned space operations budget each and every year. These estimates compare poorly with the older estimates of a launch rate for the Ares 5 of twice a year, still totally inadequate for its intended purpose. Having very infrequent launches raises the cost of each launch, the prorated cost of each launch for development and for the ground equipment, and results in loss of training skills by the pad crews during the long intervals between launches.
   
Rapid build-up requirements for base construction

If we cannot afford to use the SLS frequently, we will not be able to use it for its intended purpose (beyond LEO exploration). It will require maintaining a standing (launch vehicle) army that instead could be building the parts of a lunar or Mars base, for example. The SLS design also violates what should be a cardinal rule: design a transport system for the payloads that it is intended to carry and make sure that it is affordable for that purpose.
   
Why is the intended purpose—beyond Earth orbit (BEO) exploration—unaffordable with an SLS launcher? The two obvious kinds of exploration missions are brief visits to a target such as an asteroid, and creating a base on the Moon or Mars. It is true that a couple of missions, such as one to a near-Earth asteroid, could possibly be accomplished with a single launch. But the scientific benefits of such missions would run out rather quickly and developing an entire $30–40 billion BEO program just for visits to a couple of tiny asteroids is not justifiable. The next primary goals for the manned space program remain creating initial science and mining bases on the Moon and Mars, with early fuel production and crew safety as major rationales driving how the bases are created. Landing a crew on the Moon or Mars without establishing at least a minimal base or crew refuge at the landing site unnecessarily risks the lives of the entire crew.

The recent crisis with the International Space Station's crew transport shows that we have not yet reached the ability to allow a complex human habitat and its equipment in space to remain unoccupied for a long period of time without risk of serious damage to or loss of the habitat. If you plan to build a surface base, it is clear that due to the extreme temperature variations on the surfaces of the Moon and Mars, you must accomplish the construction of an initial base build-up within a year or two at the most. This could be called a base buildup blitz. A series of launches within a short time to support such a rapid buildup might be called a launch campaign, similar to the rate of Apollo launches or faster.

To accomplish a rapid build-up for a lunar base with a launch campaign also means you must land enough equipment within about a year to ensure the safety of the crew fr om being stranded and to protect them fr om space radiation. This means either a secure refuge where they can stay until a rescue vehicle arrives, or a second (backup) crew vehicle that needs to be landed. It also means that the crew needs a secure energy supply (which needs to be one of the first items landed to keep the other equipment warm) and a crew habitat that has been dug in and covered with lunar regolith or lunar soil before the crew arrives. Each of these requirements means a large piece of equipment fr om 1 to 25 tons (such as a reactor, an earthmover, a habitat, etc.) needs to be landed, set up and connected together (or plugged in) with electric and electronic lines as part of a functioning base.

Much of the base equipment does need to be landed before the crew arrives, with initial set-up operations to be accomplished by the teleoperation of equipment from Earth or from lunar orbit. Due to the multi-second communications delay between Earth and Moon, some delicate telerobotic operations may be best performed from lunar orbit. With continuing improvements in telerobotics, such as the Dextre robot at the Space Station, robots will be able to do more and more of the work before the crew arrives.

Therefore a launch campaign supporting a base buildup blitz is a requirement to protect both the base equipment and the crew. The relationship between the base and the crew is also synergistic: as in any system (living or mechanical), the crew helps protect the base and its equipment and the base protects the crew. Thus the crew and the base and its equipment need each other.

It is hard to imagine being able to quickly set up such a base without a launch campaign of at least five HLV launches per year. To do this you will also need one or more cryogenic propellant depots in Earth orbit to assure that the propellant to support such a launch rate from LEO to the Moon or Mars is guaranteed to be available in LEO before the buildup begins. (Without the depots, the total cargo delivered to a base site for a given number of SLS launches would be cut about in half). The depots would also need to be launched by HLV boosters. Assuming a minimum of five SLS launches per year at $5 billion a launch, the total cost is $25 billion a year, far beyond NASA's overall annual budget, let alone its human spaceflight budget. With a launch every two years, it would take a decade to provide the most minimal equipment for a surface base, and most of that would have been sitting there for many years and would thus likely be thermally damaged and unusable.

The result of the launch campaign requirement is the SLS is demonstrably too expensive to use to build a base anywhere, meaning we will be unable to afford to build either a lunar or Martian base with it. In addition, we would have just spent a huge amount of money to develop the SLS, and Congress will then be very unlikely to turn around and provide more money to build the "right" system. Even if an SLS mission slot were used every two years to launch minimal expeditions to Mars, such missions would be very risky due to the minimal mass of the crew vehicles, which need a substantial mass of shielding (fuel and equipment) around them to protect the crew from space and solar radiation. There would also not be enough mass of equipment for redundancy or to build a robust base, so the boosters could only be used for minimal "Flags and Footprints" missions to Mars, with expendable (land and abandon) equipment, essentially duplicating the "Apollo on Geritol" type of missions envisioned for Constellation by Griffin. This raises the specter of a few such minimal Mars missions being conducted in the 2030 period, after which real scientific exploration of Mars by the US would probably be put off until the 2060's due to financial exhaustion.

Other uses for and limitations of the SLS

How else could such an expensive SLS booster be used? It would be far too expensive to use for launching space-based solar power equipment, whose implementation depends totally on a drastic reduction in launch costs. Private launchers currently under development will be far cheaper by the time the SLS was operational, so that it would be grossly uncompetitive by then. Due to the lack of development money for payloads during development of the SLS booster, any large scientific payloads would need to wait until after 2021 for development starts. This would place the launch of such payloads, like large space telescopes or a large centrifuge facility for the ISS, well beyond 2025. The high launch costs would also guarantee that any scientific missions would also cost multiple billions. In addition, we need to ask a practical question, since these large launch systems are often used for over 30 years: do we really want the US to still be dependent on an expendable booster in 2030 or 2040?
   
In addition to the political impasse over booster development, the nature of the current NASA planning system results in a vicious circle, seemingly created by deliberately not including advanced technology components into future mission plans. The reasoning behind these decisions are that the components do not yet exist, but the result is that the badly needed components are never developed, since there is never a specific mission designated wh ere they will be used. Then when the mission is flown, its capabilities are greatly reduced due to the lack of the component. For example, NASA is currently budgeting money to develop cryogenic propellant depots in orbit, yet the depots are not included in or integrated into any plans for the BEO missions using the SLS. (This issue was the focus of a letter on September 27 to Administrator Bolden by Rep. Dana Rohrabacher.) Such delays and/or sapping of funds from technology programs for use by the SLS development by Congress allows mission planners to continue to exclude advanced technology solutions from future BEO mission plans.
   
HLV alternatives

What are the alternatives to the SLS? It is very obvious that the current, politically inspired plan shows a conspicuous lack of competition, in effect making the SLS funding a type of "earmark" for those specific areas of the country wh ere the "legacy" space companies operate. The best direct alternative to this is an open HLV design competition similar to that for the propellant depots or for the crew transport system. Since SpaceX has already publically announced that they can provide a true HLV with a 150-ton to LEO payload for about $2.5 billion in about five years, this shows that there is at least one company that could save the taxpayers about $20–25 billion, or more, of development costs and have the rocket ready to fly in less than half the time the government-sponsored version would be.

Assuming that a privately-developed expendable HLV (such as a Falcon Super Heavy) could be launched for $300 million per flight, as SpaceX has already claimed, such a plan would allow the payloads for the booster to be developed by NASA (using other companies) while one private company was developing the booster itself. If some payload components are also developed privately, the cost would be more like $300 million per payload instead of $3 billion. Either way would ensure that payloads would exist when the boosters were ready to use and that the payload costs were spread over the years before the launch campaign. When the payloads are ready, five to ten HLV launches could then be accomplished in a single year or two for about $1.5–3 billion (for a total cost of $3–6 billion including payloads). This would allow a very rapid and efficient base buildup on either the Moon or Mars, and provide a large amount of safety and scientific equipment for the base crew to use.

Further and even more dramatic cost savings are possible. If an open competition were held to build an HLV whose first stage boosters would be recoverable from the very start, operational cost could be cut still further. Information that SpaceX will soon be testing a reusable Falcon 9 first stage (Grasshopper), as SpaceX announced in September, shows that a very serious effort to achieve first stage reusability is continuing. The method would reduce the payload significantly due to added booster mass, but in return would drastically reduce the cumulative launch cost. After an open competition, putting some government money up front into speeding the private development of a winning reusable HLV concept would save even more operational money and allow even more launches and larger expeditions. It is quite conceivable that launches of such an HLV would cost $100 million or even less. This would be about one-thirtieth of the projected launch cost of the expendable SLS.

Based on NASA timetables and statements made by SpaceX's Elon Musk, it is clear that a BEO exploration program wh ere the major hardware elements are built by private companies and then operated by NASA astronauts would occur far sooner than one wh ere the major elements are built under close NASA supervision and rules. Such a program would have both lower development and lower operational costs. It is conceivable that such a program could take place even before NASA's first scheduled lunar launch a decade from now, due to the greatly lowered costs. For example, assuming exploration launches with privately developed boosters and payloads, which each cost about $600 million, and launches with NASA-developed boosters and payloads which each cost about $6 billion, it is easy to calculate that you could launch 10 payloads with significantly greater total mass per payload with the private system for the same price as with a single NASA-style launch. With a recoverable booster the cost ratio would be 20 to 1 or more.

Based on current development cost estimates for the SLS including Orion of $29–38 billion, even the (expendable) Falcon Heavy could launch between 300 and 400 payloads of 53 tons each for the same amount of money, starting in about two years. This would amount to between 15,000 and 20,000 metric tons of equipment in LEO, enough to build up to six one-gigawatt space-based solar power plants or to build robust science bases both on the Moon and on Mars. With a recoverable version of the Falcon Heavy, the payload masses would at least double for the same price. With a system of propellant depots available in LEO, the dry payload mass capacity would double for the same rocket.

To be truly useful, a vehicle must be affordable for its intended purpose, and the SLS is not. In following its current course, NASA and the Congress are ignoring both fiscal and physical reality. In any contest between reality and human organizations bent on ignoring realities, guess who will lose.

John K. Strickland, Jr. retired from his job as a senior analyst for the Texas Department of Transportation in Austin, Texas in June, 2009. He specializes in issues relating to access to space, planetary bases, space solar power, energy and the environment, and the overall rationale and purpose of human space activities. He has been a member of various pro-space organizations since 1961, when he joined the American Rocket Society as a student member. He is a member, at large board member, and Awards Committee chair for the National Space Society, and an Advocate with the Space Frontier Foundation, but he does not speak for any organization; his opinions are his own.
[свернуть]
   
http://www.thespacereview.com/article/1979/1
   
Это, как мне кажется, самая первая статья о неадекватности стоимости SLS задачам, которые можно решить с его помощью.

Уилбер Райт: "Признаюсь, в 1901-м я сказал своему брату Орвиллу, что человек не будет летать лет пятьдесят. А два года спустя мы сами взлетели".


Valerij

ЦитироватьRevisiting SLS/Orion launch costs
by John Strickland Monday, July 15, 2013
   
A year and a half ago, I wrote an article very critical of the Space Launch System (see "The SLS: too expensive for exploration?", The Space Review, November 28, 2011). To see if this assessment should now be updated, I checked a series of sources and found that little in the situation has changed, with no reliable cost estimates of an SLS launch yet available anywhere. It is actually amazing how hard it is to get cost estimates for any part of the SLS/Orion system. Another assessment corroborates this problem. While I was working on this article, two startling pieces of information came to light.

 It is hard to see how a large rocket like the SLS, which is, with all of its components, destroyed in the course of a launch, could possibly cost a lot less than the Space Shuttle on a per-launch basis. It will probably cost considerably more, since all of the expensive rocket engines and other equipment will either smash into the ocean at high speed or reenter the atmosphere and burn up. Note that the Space Shuttle and SLS systems are somewhat comparable in the amount of mass that reaches orbit, although the shuttle's functional "payload" is only what it carried in its cargo bay (about 20 tons) when it was being used as a launch vehicle, rather than the roughly 100-ton mass of the orbiter itself.

The shuttle, which consisted of two "re-manufactureable" solid boosters, an expendable external tank, and a refurbishable orbiter, cost about $1 billion per launch, based only on average annual program costs, and $1.5 billion per launch if development costs were also included, based on a 2011 study.

 Several launch cost estimates for the SLS/Orion system can be made. The lowest and least believable, of $500 million per launch, is fr om an unofficial NASA document that does not specify if the figure includes the estimated $30-billion development cost or even the annual operating budget, exclusive of costs for specific launches. We will assume that this is their estimate of the actual minimum cost of replacing all of the rocket equipment destroyed during a successful launch. It certainly does not include annual operations costs or payload costs.

 None of the new solid rocket booster casings for the SLS would be reused. At any rate, re-use via remanufacturing only saves about 20% of the cost of brand new solid booster segments. There also seems to be no effort to make the proposed advanced liquid fuel boosters reusable either.

 The combined development cost of the SLS and Orion is about $3 billion a year for at least 10 years. If the program were run operationally for 30 years (similar to the shuttle), the prorated development costs (not including the financing costs that would be incurred by a private company), with one launch per year, would be about $1 billion a year. The annual operating cost of the shuttle program, needed to maintain the "standing army" required to do launch operations, was about $3–5 billion. We will assume that due to the reduced maintenance costs (there being no re-usable orbiters to maintain), that the annual operating budget would be at about $2 billion.

 I had recently been seeing conflicting reports about the cost and ability to reuse the Orion spacecraft. The Orion capsule is theoretically reusable, but will land in salt water due to the decision of the designers not to use a dry land (pusher type) launch abort and landing system that would use up only 1/40th of the vehicle's entire 20 metric ton mass and instead choosing to use an old-fashioned expendable puller escape system instead. The more modern pusher system could have been used as a landing system and an abort system. It is similar to those being designed for use on the Dragon capsule, the CST-100, and the Dream Chaser, and these are reusable. The SLS launch abort system and the Orion's service module are both expendable.

 The penetration of the salt water inside the unpressurized portions of the Orion capsule makes it unlikely that it can be re-used, as it would have to be disassembled and rebuilt each time. The salt water probably would not penetrate inside the pressurized cabin, but could damage the outside of the cabin and all wiring going into it. It is unclear how much salt water penetration there would be.

 The PICA-X materials used on the Dragon capsule have been designed to withstand entry from a return lunar trajectory and were derived from NASA-developed PICA. If the Orion could be reused, the older style heat shield used on Orion would need to be replaced after each flight.

Based on several external estimates, the SLS/Orion combination can be launched once a year, assuming NASA's current limited, flat budget continues. Equipment at Michoud would probably allow two first (core) stages to be built each year. So, if we assume an annual SLS operating budget of $2 billion, with one launch per year at $1 billion for the rocket and $1 billion for the spacecraft, that brings us up to $4 billion a year, similar to the Shuttle's operating budget. In this case, the cost of replacing the rocket and spacecraft take up a much larger portion of the total budget, and the cost of maintaining the workforce and maintaining and refurbishing the existing vehicle fleet a much smaller portion. The cost of maintaining the launch facilities would be similar. However, the operating budget is the most uncertain value.

 The bill for an SLS launch, at the flight rate of one launch per year, might then look like this:


   
The actual annual expenditure would be only $4 billion, but due to the currently flat NASA budget, declining due to both inflation and politics, a $4-billion share of the budget is a bigger share than the shuttle took up in the past. The $1 billion per year during the operational period that is charged to the development is a real cost, since that money was not available to develop other vehicles or equipment for an entire decade.

 The current large SLS/Orion development budget of about $3 billion a year precludes any development of any other payloads for the SLS. In an article in 2012, Chris Kraft and Tom Moser point out that development of "the crewed lunar lander, a multi-mission space exploration vehicle (MMSEV), a deep space habitat, a lunar surface rover and other lunar infrastructure" are being crowded out by the SLS development effort, so that by the time the SLS would be ready to use, there would be little or no hardware for it to launch. The same would be true for any specialized hardware needed for asteroid or Mars exploration. In addition, they point out that the "the extra $4 billion to $5 billion per year needed to make an SLS-based exploration strategy work" will be unaffordable given the worsening fiscal situation. The dilemma posed by this situation is that NASA can afford to slowly develop a giant rocket, or develop payloads to launch on the rocket, but not both at the same time.

 Coincidentally with my new analysis, a recent article appears to support those who have been saying that NASA cannot and will not launch the SLS very often. A June 28, 2013, article in Space News, covering an official media tour of the Michoud plant and touting its new welding equipment, seems to indicate that NASA intends to fly the SLS only about once every four years even after the rocket's development is completed. Previously the slowest launch rate anyone predicted was every two years. Even if NASA wants to fly the SLS more often, the cost of preparing new payloads for it may still greatly lim it its flight rate. The Space News article quotes Steven Squyres, chairman of the NASA Advisory Council, as saying, "We have no experience with a human-rated flight system that only flies every two or three or four years." This then brings into question the readiness of a launch team to do safe launches at rare intervals. This is a significant issue if you remember the problems of starting up shuttle launches again after the long launch gaps after the two shuttle accidents.

 Information in another unofficial schedule posted on the Wikipedia page for the SLS (current as of July 1, 2013), indicates that NASA now does not plan to complete development of the 130-ton Block II version of the SLS until as late as 2030. Estimates of the payload up to those dates are between the initial 70 tons and up to 105 tons. This also implies a stretched out program and continuing development costs for another 15 or more years. The US government should either decide to turn the SLS into a reusable HLV booster, or open a competitive bidding for a privately designed and built reusable HLV.


 This information radically changes the assumed cost of each launch, since now, over a presumed 28-year lifespan, starting in perhaps 2022 and lasting presumably until 2050, the rocket would be used only seven times, and for more than a third of its lifespan, not able to launch the promised 130 tons. Its $30-billion development cost would then need to be divided among the few actual launches, not over all the years of the 28-year period, and would be about $4.3 billion per launch. This share of the launch cost represents money that could have been spend on payloads in years past. The per-launch cost of the rocket now jumps from $5 billion up to about $9 billion. The continuing annual cost of maintaining the workforce that allows launches to occur are rare intervals would need to be counted as part of each launch cost. The lesson learned from the Space Shuttle era is that the manpower costs are the largest cost, which is demonstrated again here. The cost table shown above now looks very different. Note that launch prices per ton and per pound for the initial 70-ton SLS version would be almost double that for the 130-ton version.

 Revised bill for one SLS launch (one launch every 4 years):
   

   
So, compared to the shuttle, how much would an SLS launch (of 130 tons) cost per pound if it was launched at several different conceivable rates. I have put the numbers for the intermediate launch frequencies into the figure below. Prices per pound for the SLS would be 86% higher if it launches only 70 tons.
   

   
So the full-sized payload version of the SLS is slightly cheaper that the shuttle at one launch per year, due to the roughly five-fold increase in actual payload compared to the shuttle when it was used as a payload delivery system. This means that the SLS launched once a year will be six times as expensive as a Falcon 9 expendable launch and 15 times as expensive as a Falcon Heavy expendable launch.

 The upshot is that the situation described by my previous assessment (and those of many others) remains accurate and in some respects is worse:
No hardware to be launched by the SLS other than the crew capsule can be developed until the SLS is developed.
The SLS will only be able to perform single launch manned space "stunts" or a few super-expensive science launches at very rare intervals.
Due to the available share of the NASA budget that would be taken up by single SLS launches, the SLS will not be able to support base construction anywhere in space, at L1/L2, GEO, on the Moon, or on Mars.
The SLS is draining away the lifeblood—funding—of the space program, which should, by all rights, be used to speed up the development of private rockets and end payments to the Russians for space station crew launches as soon as possible.
The SLS is a ridiculously expensive way to launch astronaut crews into orbit. With a crew of six, and assuming that each astronaut's share of the Orion's 20-ton mass is about three tons, the lowest conceivable cost per seat is $88 million and the most expensive is $368 million, even assuming that some other payload is being launched along with the Orion capsule. It would be much cheaper to continue to use the expensive Russian launch service.

 The US government should either decide to turn the SLS into a reusable HLV booster, (something that a private company with a tiny fraction of the US government's capabilities is already trying to do), or open a competitive bidding for a privately designed and built reusable HLV. Working on a reusable HLV, even one based on the SLS, would not reduce the current work force, and once it was ready for flight, it would enable a great expansion of the space work force in other areas such as spacecraft development and construction. We really do need a HLV booster to launch very wide payloads (up to 15 meters in diameter), but we cannot afford to launch such payloads on an expendable booster.

 Some of the money being spent on the SLS/Orion program may not be wasted, such as the programs to redevelop modern versions of large Apollo-era rocket engines that could be used on a variety of other vehicles.

 The fact that, in spite of my best efforts, the estimates used in this reassessment of the SLS may or may not be accurate or fair is countered by the reality that getting hard flight cost, hardware construction cost, and annual operational cost numbers out of NASA officialdom is impossible. In no way should criticism of a NASA program decision should be interpreted as criticism of NASA employees, especially as this program is, to a large degree, being forced on NASA by the Congress.

John Strickland is a member of the board of directors of the National Space Society and an Advocate with the Space Frontier Foundation, but he does not speak for any organization: his views are his own.
   
http://www.thespacereview.com/article/2330/1

Уилбер Райт: "Признаюсь, в 1901-м я сказал своему брату Орвиллу, что человек не будет летать лет пятьдесят. А два года спустя мы сами взлетели".


Valerij

ЦитироватьOn NASA's Space Launch System (SLS) and Orion Spacecraft Programs
By David Brandt-Erichsen May 2012
   
I have seen little enthusiasm about SLS/Orion within the space movement (in which I have been involved for 34 years), but many space enthusiasts consider these programs to be "better than nothing" (which is about the best I've heard in their favor).

 But I ask you: Would you consider it "better than nothing" if NASA designed and built its own automobiles for $2.5 million each rather than go to a local car dealer and buy them for $30,000 each?  Or would you consider that to be an insane policy that should be immediately cancelled?  I maintain that the SLS/Orion program is the exact equivalent and should be immediately cancelled.

 I have two names for the Space Launch System (SLS):
   
 The Monster Cost Pork Rocket to Nowhere (MCPoRN).

 The cement overshoes of the space program.

 NASA is very secretive about the cost of SLS because they are not proud of it.  NASA even managed to get an independent cost analysis of SLS by Booz Allen Hamilton to be published without actually giving any cost numbers!  See:

SpacePolitics.com, August 23, 2011: An independent cost assessment, without costs http://www.spacepolitics.com/2011/08/23/an-independent-cost-assessment-without-costs/

However, costs and plans have leaked out in the following two articles (a later article in the New York Times pegged costs even higher):

 Orlando Sentinel, August 5, 2011: New NASA Moon rocket could cost $38 billion http://articles.orlandosentinel.com/2011-08-05/news/os-nasa-next-moonshot-20110805

NASA Spaceflight.com, July 27, 2011: Preliminary NASA plan shows Evolved SLS vehicle is 21 years away http://www.nasaspaceflight.com/2011/07/preliminary-nasa-evolved-sls-vehicle-21-years-away/

In brief, the projected schedule and costs are as follows:
 First launch of SLS in December 2017, carrying an unmanned Multi-Purpose Crew Vehicle (MPCV, otherwise known as Orion) around the Moon and back. Cost: Between $17 and $22 billion.

 Second launch of SLS in August 2021, carrying a manned Orion vehicle around the Moon and back. Cost: An additional $12 to $16 billion.

 Projected flight rate beyond that is one mission per year, alternating between manned and cargo missions, at a cost of about $1.2 billion per flight.

 Note up front that with a flight rate of one per year, SLS can pull off a few stunts but it is essentially impossible to ever build a lunar or Mars base, or for that matter, really do anything particularly useful in establishing a true beachhead in space (hence, Rocket to Nowhere).  The rocket is just too expensive to use.

Спойлер
Now let's compare these costs with alternatives, in particular with the SpaceX Falcon Heavy, scheduled to launch in 2014, well before SLS.  See:
   
National Space Society: The SpaceX Falcon Heavy Booster: Why Is It Important? http://www.nss.org/articles/falconheavy.html

The lowest costs listed above for the first two flights of SLS would total $29 billion to launch two 70-ton payloads for test flights which would duplicate the Apollo 8 flight of 44 years ago. This equals 140 tons to orbit. (A later version of SLS could launch 130 tons in a single launch but is not scheduled until 2032).

 In comparison, $29 billion could buy 226 flights of Falcon Heavy (which has zero development cost to taxpayers).  At 53 tons each this equals 12,000 tons, or 85 times more payload to orbit for the same cost.  Do you think maybe NASA could figure out a way to build a lunar base if it used that kind of launch capacity instead?  I rather suspect it could.

 With this enormous cost difference, does SLS represent a sane space policy?  

You might argue that Falcon Heavy has not yet flown (although neither has SLS), and that there is no guarantee it will work (whereas nobody argues that NASA won't be able to get SLS to work). But it is unlikely that Falcon Heavy won't work, and it would be even more unlikely if we had a rational space policy.  First of all, Falcon Heavy is a scaled up version of an already proven rocket, the Falcon 9 (Intelsat has already made an agreement with SpaceX for a Falcon Heavy launch).  Second, even if it did have problems at first (true of all rocket systems, even NASA's), if NASA wanted to purchase Falcon Heavy flights and there were severe problems with it, under a rational space policy NASA could send over a few of its best engineers and offer a few million dollars in bonuses (chickenfeed) for those most instrumental in solving those problems. I betcha that would work. The result would be billions saved and a system we could actually DO something with.

 The budget for SLS for fiscal year 2012 was $1.8 billion and for fiscal 2013, $1.9 billion. That in itself could have bought 29 Falcon Heavy flights (1,500 tons to orbit).  SpaceX has also stated they could fully develop a 150-ton payload rocket for $2.5 billion (less than what has already been spent on SLS) with payments to be made only after reaching specified milestones along the way.  (Cost per ton to orbit of this "Super Heavy" is projected to be the same as for the Falcon Heavy.)

 The budget for Orion for fiscal year 2013 is $1 billion.  Although the price of a Dragon spacecraft has not been announced, an upper limit can be inferred from the total cost of the NASA contract with SpaceX, and it is safe to say that just this single year's budget for Orion would buy several Dragons off the shelf.  

Update: "Between 2011 and 2013, the Orion project received only about $3.6 billion." (Emphasis added. From Orlando Sentinel article NASA watchdog cites Orion development problems, August 18, 2013.) http://www.orlandosentinel.com/business/os-orion-problems-report-20130815,0,1655833.story

Dragon is superior to Orion in both cost and function, and unlike Orion it has already flown successfully. The human-rated version of Dragon (not yet flown) will be able to "land on any solid surface in the solar system" (Orion can only do a water landing).  Like Orion, Dragon can carry a crew of seven and has a heat shield designed for the higher re-entry velocities of a lunar return. The only advantage of Orion is that it is a bit roomier, but considering the cost difference this is quite trivial (and if it really mattered, you could still fly two Dragons for less than one Orion).

 And Dragons are available off the shelf from an existing factory.  SpaceX has stated: "Depending on demand, Dragon production is planned for a rate of one every six to eight weeks."  It just makes no sense to duplicate this at much higher cost.  That is an insane space policy, equivalent to having NASA design and tool a new car factory instead of buying their cars off the shelf.

 The price of a Bigelow habitat has not been announced, but I strongly suspect you could buy a Dragon plus a Bigelow habitat for less than the cost of one Orion.
   
See this 4-minute video comparing Orion and Dragon:    
http://www.youtube.com/watch?v=G24bTBLhYyo
(The video does not point out that Dragon can land on any solid surface in the solar system, which Orion cannot.)
   
Regarding pork, it is well known that SLS (sometimes called the "Senate Launch System") was foisted on NASA by politicians who have particular rocket companies in their districts. Nobody ever pushed for SLS because it was a Good Idea, but only because it benefited particular companies that had built space shuttle components. There is no other justification for SLS.

 The purpose of NASA is to research cutting edge space technologies. SLS/Orion does not do that. It is time to recognize that NASA should no longer be in the rocket building business but should buy such components off the shelf instead. They are now available off the shelf, which was not true during the Apollo and Shuttle programs.

 SLS/Orion are dead ends that cannot possibly succeed because (1) we cannot afford to use them and (2) because they are redundant duplications of vastly cheaper alternatives. Eventually these facts will become so obvious and undeniable even to politicians that the programs will collapse under their own weight and be cancelled, and the sooner this happens the better.

 If SLS ever does actually fly, I will not celebrate but instead will mourn. Flying SLS would be a monument to colossal stupidity.
[свернуть]
   
http://www.davidbe.net/sls.html

Уилбер Райт: "Признаюсь, в 1901-м я сказал своему брату Орвиллу, что человек не будет летать лет пятьдесят. А два года спустя мы сами взлетели".


Valerij

ЦитироватьSpace Launch System is a threat to JSC, Texas jobs
By Chris Kraft and Tom Moser | April 20, 2012 | Updated: April 20, 2012 8:20pm
   
Цитировать
   
The costs of developing the Space Launch System, shown in this NASA illustration, are crowding out funding for other projects that would be managed by JSC.
   

Our nation has entered a time of severe fiscal constraints in the face of trillion-dollar-per-year federal deficits. While NASA's Space Launch System (SLS) is a well-intentioned program, we cannot afford to provide NASA with the extra $4 billion to $5 billion per year needed to make an SLS-based exploration strategy work. As a result, the human deep space exploration program is on the verge of collapse, which will have severe economic consequences for Texas as well as the nation.

Спойлер
Unless something changes soon, the current situation will further degrade and could easily destroy critical human space exploration expertise at NASA's Johnson Space Center (JSC) that we will never regain. Unless something changes soon, many thousands of high-wage Texas jobs will be lost forever.

The current national human exploration strategy, which is based on development of the SLS, is economically unaffordable. The SLS-based strategy is unaffordable, by definition, since the costs of developing, let alone operating, the SLS within a fixed or declining budget has crowded out funding for critical elements needed for any real deep space human exploration program. Most of these critical elements would be managed by JSC. They include the crewed lunar lander, a multi-mission space exploration vehicle (MMSEV), a deep space habitat, a lunar surface rover and other lunar infrastructure. The development of these critical elements has been delayed until the mid-2020s and the 2030s, so real human exploration beyond Earth will not begin until the late 2020s or 2030s.

This is not only politically unsustainable - it is technically unsustainable.

At present, JSC has only a few significant jobs: completing the development of the Orion Multi-Purpose Crew Vehicle, operating the International Space Station (ISS) and supporting the Kennedy Space Center-led commercial crew program.

Consider just two of JSC's strategic capabilities: Mission Control and Operations and Engineering and Development. The more famous of the two - Mission Control and Operations - was created by JSC engineers and is a unique capability. With the space shuttle retired, ISS assembly complete, and the first crewed Orion flight a decade away, JSC's Mission Control has much less to do. Supporting increasingly routine ISS operations requires no more than several hundred people at Mission Control, a small fraction of recent levels of 2,500 personnel.

This Death Valley of actual spaceflight operations and development also threatens JSC's crown jewel, the engineering organization that undergirds these more visible achievements. JSC's world class engineering and development capability created the concepts, designs and development for every American human spacecraft that has flown to space. JSC's unique multi-discipline systems engineering and spaceflight technical expertise - built up over five decades - is the envy of the world's space agencies and aerospace industries.

With ISS complete, with no significant funding for the deep space habitat or MMSEV, and with the cancellation of the crewed lunar lander and other lunar surface systems, there is minimal development work for JSC's engineering teams. They are now limited to helping complete the half-finished Orion and supporting KSC on commercial crew.

With no clear destination and no money to pursue one, there are not enough projects to inspire and train the next generation of managers and designers who will, presumably, be needed a decade from now to start developing actual exploration hardware. This is a going-out-of-business strategy.

For all these reasons, the current NASA exploration strategy is a plan for the withering or even destruction of JSC, and with it the stagnation and decay of the Texas space industry.

SLS is killing JSC. SLS is killing Texas jobs. SLS is killing our national space agenda.

We are wasting billions of dollars per year on SLS. There are cheaper and nearer term approaches for human space exploration that use existing launch vehicles. A multicenter NASA team has completed a study on how we can return humans to the surface of the moon in the next decade with existing launch vehicles and within the existing budget. This NASA plan, which NASA leadership is trying to hide, would save JSC and create thousands of jobs in Texas.

It is time for Texas' elected members of Congress to wake up and do something about it before it is too late.
 

Kraft is former director of NASA's Johnson Space Center and former director of JSC Mission Control; Moser is former director of JSC Engineering, and former director of NASA's Space Station Program.
[свернуть]
   
//

Уилбер Райт: "Признаюсь, в 1901-м я сказал своему брату Орвиллу, что человек не будет летать лет пятьдесят. А два года спустя мы сами взлетели".


Valerij

ЦитироватьTooling, Processes Coming Together For 'Affordable' Space Launch System
By Dan Leone | Jun. 28, 2013
   
Цитировать
   
Each SLS will be powered by four surplus space shuttle main engines, also known as RS-25s. NASA has 16 engines in storage at the Stennis Space Center in Mississippi. Credit: Jason Rhian, Americaspace
NEW ORLEANS — Although NASA's heavy-lift Space Launch System (SLS) will not fly often, it will fly affordably and safely, William Gerstenmaier, NASA's top human spaceflight official, said here during a June 21 tour of the Michoud Assembly Facility, where the rocket's core will be built.

The tour, attended by other NASA officials, local and state government representatives, and members of the media, also included a visit to the nearby Stennis Space Center in Mississippi. SpaceNews' travel and lodging expenses for the two-day visit to New Orleans were paid for by Boeing, prime contractor for the SLS core stage.

Gerstenmaier, NASA's associate administrator for human exploration and operations, was on hand not only to tour Michoud but also to mark the start of operations for the facility's new Vertical Weld Center, a three-story machine — built by Boeing, Futuramic Tool and Engineering Co. of Warren, Mich., and PaR Systems of Shoreview, Minn. — that will weld aluminum alloy panels together to form the cylindrical segments of the 8.4-meter-diameter SLS core stage.

Using these and other tools, and an employee work force of "significantly less than 1,000," NASA and Boeing could produce as many as two SLS cores a year, according to Patrick Whipps, the agency's resident manager for Michoud. The machines unveiled by NASA June 21 are significantly more advanced than those used at the facility to build the space shuttle's external fuel tanks, Gerstenmaier said. That means a leaner, comparatively cheaper manufacturing process.

"Typically, there were three or four or five different tools required to do the same job you're seeing with one tool here," Gerstenmaier told SpaceNews of the Vertical Weld Center. The tool not only welds SLS core segments together but allows engineers at Michoud to inspect the weld as soon as it is completed — something that during the space shuttle program would have required moving the hardware to another workstation.

For SLS, Boeing has "taken advantage of modern manufacturing, state-of-the-art things to try to lower our overall operating costs that makes this a very affordable rocket, even at low production rates," Gerstenmaier said.

Each SLS will be powered by four surplus space shuttle main engines, also known as RS-25s. NASA has 16 engines in storage at the Stennis Space Center.

SLS is to make its maiden flight in 2017, when it will carry an empty Orion crew capsule to near-Moon space and back. Another flight would follow in 2021 and, depending on factors both technical and political, could see a crew of astronauts travel to a captured asteroid NASA wants to redirect to a high lunar orbit using a yet-to-be-built robotic spacecraft.

Notionally, SLS would next fly in 2025, giving the rocket a launch rate of once every four years. NASA has been spending about $1.8 billion a year on SLS development, including construction of a rocket test stand in Mississippi, and associated launch infrastructure at the Kennedy Space Center in Florida. Add in the cost of the rocket's companion crew capsule, the Lockheed Martin-built Orion, and the tab rises to nearly $3 billion a year.

Given the expense, and the enormity of the mission SLS has been charged with carrying out — NASA says the rocket is essential for one day launching humans to Mars — the low flight rate has raised red flags for some industry watchers, most recently during a June 19 congressional hearing on a draft NASA authorization bill.

"We have no experience with a human-rate flight system that only flies every two or three or four years," NASA Advisory Council Chairman Steven Squyres told members of the House Space, Science and Technology Committee. "And I believe that's cause for serious concern. It's not just simply a matter of maintaining program momentum. It's not even purely a matter of efficiency. It's also a matter of keeping the flight team sharp and safe."

Squyres has raised that point before, both in congressional testimony and before a National Academies panel charged with reviewing NASA's human spaceflight program.

Asked whether the rocket's low flight rate raised concerns for either the safety of the crews who will ride it or the reliability of the vehicle itself, Gerstenmaier said "no."

"You may not see the extensiveness of the testing [with SLS] that you did with Apollo, but the testing is every bit as rigorous," Gerstenmaier said, noting that the big rocket's ongoing preliminary design review — a milestone in government development programs where a proposed design faces scrutiny from outside experts — is being informed by "a couple terabytes of data" gathered by engineers.
   
Michoud's mission
   
Michoud has had a hand in the space program since the beginning, building the core stage for the Saturn 5 rocket that powered the Apollo Moon exploration program and the external tank for the now-retired space shuttle, which flew 135 missions between 1981 and 2011.

Like the canceled Constellation program, a Moon-return project conceived by the administration of former U.S. President George W. Bush, SLS will not employ nearly as many workers as the space shuttle program did.

Michoud is case in point. In the shuttle era, about 2,500 people worked at Michoud. Most were employed by Lockheed Martin, the prime contractor for the shuttle external tank and facility manager. The facility, managed since 2009 by Jacobs Technology Inc., now employs fewer than half that number. By way of comparison, there were about 10,000 people working at Michoud during the Apollo program, according to Whipps, NASA's resident manager there. If NASA wanted to scale up SLS flight rates to the five, six or more a year that were common in the shuttle era, Michoud would need to hire more people and NASA would need to invest in more manufacturing tools. The Vertical Weld Center, Gore Weld Tool and Circumferential Dome Weld Tool that are there now could make two SLS core stage structures a year at most, Whipps told SpaceNews.

"It all depends on flight rate," Whipps said.
   
http://www.spacenews.com/article/civil-space/36012tooling-processes-coming-together-for-'affordable'-space-launch-system

Уилбер Райт: "Признаюсь, в 1901-м я сказал своему брату Орвиллу, что человек не будет летать лет пятьдесят. А два года спустя мы сами взлетели".


pkl

Вообще, исследовать солнечную систему автоматами - это примерно то же самое, что посылать робота вместо себя в фитнес, качаться.Зомби. Просто Зомби (с)
Многоразовость - это бяка (с) Дмитрий Инфан

Valerij

#6
Цитироватьpkl пишет:
Ну а если вкратце, что резюмируете?
   
Я хочу, что бы резюме написал Ну-и-ну
Попросите его об этом.
Мне некогда, завтра с раннего утра на работу, и к ноуту вернусь через два дня. В это время буду временами заглядывать на планшете.

Уилбер Райт: "Признаюсь, в 1901-м я сказал своему брату Орвиллу, что человек не будет летать лет пятьдесят. А два года спустя мы сами взлетели".


frigate

#7
Aviation Week & Space Technology 23 June 2014, page 18
"Селена, луна. Селенгинск, старинный город в Сибири: город лунных ракет." Владимир Набоков


Alex_II

ЦитироватьSFN пишет:
Пишут никакие деньги не спасут
 SLS Has Problems That Money Alone Will Not Fix
Правда конкретных проблем кроме денег не называют...
И мы пошли за так, на четвертак, за ради бога
В обход и напролом и просто пылью по лучу...

Александр Ч.

Кларк "подтянулся":
http://spaceflightnow.com/2014/12/16/despite-budget-boost-space-launch-system-will-not-fly-before-2018/
ЦитироватьNASA's heavy-lifting mega-rocket and its ground support systems at Kennedy Space Center in Florida will not be ready for launches until at least mid-2018, even with extra funding approved by Congress, the space agency's senior human spaceflight official told lawmakers.
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