Space-Based Solar Power

a public discussion sponsored by the Space Frontier Foundation

The Genesis Briefing

Posted by Coyote on June 19, 2007

Lt Col Mike “Green Hornet” Hornitschek found himself at Air War College with a paper to write. He did it on DoD energy transformation (see “War Without Oil: A Catalyst for True Transformation” in the Air Force Journal of Logistics). It included some discussion of space solar power. Then he came to the Pentagon where he met some fellow enthusiasts of space solar power (Lips & Dr Evil) who helped him prepare a PowerPoint briefing on the subject. They formed the Space Solar Power Cabal (read about them in “About the Study” above). The briefing was presented widely around Washington and inside the Pentagon.

See for yourself the briefing they built that led to the creation of this study:

Space-Based Solar Power: An Opportunity for Strategic Security

Comments?

Coyote

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23 Responses to “The Genesis Briefing”

  1. Mark Hopkins said

    Coyote,

    Be careful of the argument that greatly reduced transportation costs to LEO (say $200 per pound) are necessary for economical SSP and therefore we need to lower launch costs before we can get serious about SSP. Launch cost reduction is a hard problem. Considerable effort has been made in this area for the last thirty plus years in the U. S. and elsewhere with little result.

    There is an alternative approach. First establish with confidence that SSP will be economical, if one last problem is solved – launch costs. Progress in the non launch area of SSP costs has been rapid during the last few decades, despite the fact that little has been spent directly (as part of an SSP dedicated program) on the relevant set of problems.

    The potential market for electricity is extremely large. If the only remaining problem is launch costs, then rational decision makers, concerned primarily with profits, will be willing to spend a great deal to solve this problem. In such a situation, an R & D expenditure of say $40 billion, given confidence in success, is perfectly reasonable and would be done.

    In short, if the other SSP problems can be solved, then launch costs will probably take care of themselves.

    In reality, it is more complicated. Cost and risk reductions in any of the SSP problems make it easier to solve the remaining problems, because the resources that it makes sense to devote to the remaining problems rises. My point is to not become overly focused on launch costs.

  2. Coyote said

    Mark,

    That is a refreshing way of looking at it! I have pondered the launch cost problem over and over without my small pea-sized brain getting over the hump. That’s probably the mental mountain others are unable to get over, too.

    So, you recommend spending whatever money we might get in solving all of the other problems–which seem far easier, to be quite frank–and simply be confident that if we make space-based solar power viable that the appropriate investors will resolve the launch frequency and cost problem for us.

    Dude! Thank you. I think that is a great strategy. What do others think?

    Coyote
    P.S. Mark, I was so locked in thinking forward that I neglected to think this problem backwards. Launch becomes the major impediment both ways. I owe you a beer!

  3. interested party said

    Absolutely the right approach! Putting launch as the first step to doing anything likely means nothing gets done because it will seem to hard. This can allow progress to made on multiple fronts at least to the point that an absolute decision on launch is required (which is in order to produce an operational SSP not to do risk reduction or scaled demos). Take the advise and run with it.

  4. Coyote said

    Interested Party, et al.,

    I’ve discussed this with the team and we seem to be in agreement with this approach…solve all the other problems and wait for the business case to make itself when; 1) launch costs go down, and/or 2) energy prices to go up, 3) hydrocarbons are banned.

    Coyote.

  5. spacepolicy said

    Coyote,

    I agree that some of the other problems are easier to solve than “launch” and that we should not wait for launch to be solved to work on them. I also agree that as we solve them, and that launch remains the last key pole in the tent, that it becomes easier to justify increased federal investments/incentives for launch cost reductions.

    I agree with your statement that “solve all the other problems and wait for the business case to make itself when; 1) launch costs go down, and/or 2) energy prices to go up, 3) hydrocarbons are banned.”

    I think I would modify your statement above a little — some of the “other problems” have low cost launch in their critical path, so they are linked. For example, “ubiquitous on-orbit operations” basically requires a commercial industry that is profitably carrying out many new capabilities at low-cost, such as on-orbit repair, assembly, and maintenance (using both humans and robots) … and commercially owned and operated reusable space tugs. After we have very low cost launch, these capabilities will grow naturally.

    I agree that we should not look at launch costs as the “first step”. It is one of many steps, and we can & should appropriately work on them in parallel.

    All that said, I just want to be clear that we should NOT wait to *SMARTLY* invest in addressing the launch cost challenge. For example, there are smart, low-cost actions that we can take now to help build an American reusable spaceplane industry.

    - Charles

  6. Mike Snead said

    1. Three points from reviewing the presentation.

    a. My projections of the development cost of a 25K to 500km two-stage, vertical-launched, horizontal landing, fully-reusable space access system is about $30B each based mass-based cost methodologies and detailed conceptual design analyses to establish the costs. The production unit costs are in the range of $1B for each flight set. The total development and production cost is about $36B generating four operational systems. The recurring mission costs start at about $30M and decrease to about $20M. These are not government business as usual estimates but those based on use of TRL 6-9 technologies and several other cost reduction methods proposed by Dr. D. Koelle in Handbook of Cost Engineering for Space Transportation Systems. Two design/production/operation independent systems are required for assured space access making the total cost about $72B. These values include 15-20% margins for typical cost overruns. What is needed is about $100M in FY08 to undertake conceptual design analyses to establish 3-4 contractor-preferred designs along with associated cost and schedule estimates. The $6-10B estimate for development in the presentation is, I believe, very low and should be questioned.

    It is also important to understand that with a normal 6-10 year design cycle time (remember we went from the first-gen 707 in 1959 to the third-gen 747 in 1970), a first-gen system can be operational in 2016-2018, a second-gen system in 2023-2025, and a third-gen system in 2030-2032, each increasing safety and decreasing costs. By the time space-based solar power starts to ramp up, passengers and cargo will be flying on second- and third-gen systems.

    b. The presentation says that no astronauts are now required for construction of the space-based solar power. I do not see how this statement can be supported. I understand that advocates of robotic approaches use this as a “selling point” to gain financial support for their efforts, but Murphy’s Law saws otherwise. The expectation should not be established that this effort can be undertaken successfully without direct and continuing human interaction. The entire spacefaring logistics infrastructure must be based on the presumption of a substantial human presence in space. This is what becoming a true spacefaring nation is all about.

    c. The presentation implies that heavy spacelift will not be needed and that any 25K lb launch system will be adequate. This is incorrect from a cost point of view, from a flight rate point of view, and from a scale point of view. Expendable launch systems are far more costly than fully-reusable systems. The cross-over point is about 15-20 launches per year. Expendable launch systems cannot achieve the flight rate that is needed nor provide the passenger transport safety that is needed. Terrestrial production of space-based solar power systems may not scale up practically, taking us into the extraterrestrial resource model. I do not believe that this was addressed. If the initial space-based solar power systems will use terrestrially-fabricated units, as I expect would happen, then it would be appropriate to use a fully-reusable heavy spacelifter as costs always fall with scale. Such a system could come into operation by 2025 following a Shuttle-derived system (partially-reusable), with a comparable 80-100 ton payload capability, being brought into operation in 2016-2018.

    2. Considerable effort had been placed in the last two decades on trying to develop the wrong new launch systems leading to public confusion that some form of technological “space access barrier” exists. (This is a very common “belief” among the younger aerospace engineering community, as well.) There are many reasons why this happened. However, I do not believe there is any question within the aerospace industry that (1) the U.S. can successfully develop near-term, fully-reusable, two-stage space access systems, and (2) that should such systems be developed using “aircraft-style” system engineering principles and practices leading to fully-reusable systems with “aircraft-like” safety and operability, then the recurring mission costs, compared with current costs, will fall dramatically. If, however, such systems are designed, built, and operated as a “reusable” expendable launch vehicle — hence, the name reusable launch vehicle — then I do not see the desired change in space access paradigm being achieved that is needed.

    Mike Snead
    http://spacefaringamerica.net

  7. Coyote said

    Charles,

    Your points are well taken. We should emphasize at every appropriate opportunity that solving the spacelift problem will likely be the final impediment to SBSP…as it is to virtually all current and future space enterprises as well.

    Please forgive this editorial note, but I find it simply astonishing that the in 2007 that we have not solved what has become the “age-old problem” of all spacefaring activities–access to the medium.

    In my humble opinion, this indicates a lack of strategic vision among nations to integrate space into our economic models. To raise Dennis Wingo’s point, 15th century venture capitalists had to break the flat-earth mindset. Today’s venture capitalists must break the geocentric mindset.

  8. Mike Snead said

    Charles and Coyote,

    Please clarify specifically what spacelift problem(s) exists in your view beyond the fact that adequate spacelfit does not exist today. What are the problems and what are the solutions that you see as needed?

    Mike Snead

  9. Coyote said

    Mike,

    Thanks for this necessary and well warranted question. We need to be specific, don’t we?

    There are seven problems with current spacelift as it affects me, as the SBSP manager, and as the chief of Dream Works:

    1. It costs more than I would like to pay. In fact, launch cost seems to ruin the business case for many initiatives.
    2. It takes too much lead time to plan for a lift.
    3. I have limited launch pads at limited launch ports, and too many rockets occupy pads for months–making a scheduling bottleneck.
    4. I have to design everything not only for space, but for center of gravity, symmetrical balance, and G-loading during launch.
    5. Lift is usually one-way…I can’t make a return trip.
    6. The market is over capacity and I am expected to share the wealth.
    7. Man-rating rockets is a long, hard, tedious, expensive process.

    Your thoughts, Good Sir?

    Coyote

  10. There are seven problems with current spacelift as it affects me, as the SBSP manager, and as the chief of Dream Works:

    1. It costs more than I would like to pay. In fact, launch cost seems to ruin the business case for many initiatives.

    True – however, it can also be argued that for the “successful” space markets, launch is a cost of doing business and they have proceeded anyways (GEO comsats for example). This was a common refrain heard during the late 90s from the satellite mftrs when responding to the startup RLV companies – specifically, RLVs were saying “but if you invest in new launch technologies (ours) then new satellite businesses (leo constellations) would be profitable and thus create new business for you.” The manufacturers general response was “we’re not in the launch business”. The ELV companies had a different reason – which, arguably, is also why they were happy not getting involved in any real RLV projects (VentureStar notwithstanding): their rockets were profitable, and they didn’t see demand elasticity warranting a price reduction. A Delta II cost $65m at that time (approx), but that was then cost to the customer, not Boeing’s cost. But Boeing had no reason to drop the price to say $50m because they didn’t see enough new satellite business to create a greater total profit to them. Say, for example, the actual cost to Boeing was $40m to make a D2 – then at existing price the margin would be $25m. Let’s say they sold 8 each year. That’s $200m profit on the line then. However, if they reduced the price to $50m, their margin drops to $10m per rocket. Simply to make the *same* profit as before, 12 more customers would have to line up – a 150% increase in their market share. They didn’t see the demand of “marginal” business cases that would become real with a $15m change in launch price as being real enough to take the plunge. I would posit that they were correct.

    Now an order of magnitude reduction would be interesting – but can you imagine a Delta 2 rocket being available for $6.5m? Neither can I.


    2. It takes too much lead time to plan for a lift.

    Ah, the dreaded manifesting cycle. This is a very real bugaboo with the existing architecture, be it ELV or Shuttle.


    3. I have limited launch pads at limited launch ports, and too many rockets occupy pads for months–making a scheduling bottleneck.

    From a production operations management scheduling point of view, this needs to be looked at much more deeply. Classic B-school type stuff. Other than weather-related delays or mission-specific launch windows, there should be no reason a rocket sits on the pad with a payload for more than a very short period of time (defined in days or at most a week).


    4. I have to design everything not only for space, but for center of gravity, symmetrical balance, and G-loading during launch.

    Can’t help there – physics is an ugly reality check. Now if you had CRATS, you could design for on-orbit assembly, which removes a big part of the traditional “shake and bake” design problems. Dennis Wingo’s insightful, yet ahead of its time, plans for on-orbit assembly are a great starting point.


    5. Lift is usually one-way…I can’t make a return trip.

    That’s the biggest problem with the (E)LV model – the E. Imagine how expensive it’d be for me to fly to DC from Sydney if they had to blow up the airplane with every flight (after the passengers and cargo were removed, of course!) and build a new one for the next flight…


    6. The market is over capacity and I am expected to share the wealth.

    ?? Not sure I follow this one?


    7. Man-rating rockets is a long, hard, tedious, expensive process.

    And really, at this point, an exercise in statistical nonsense. When aircraft are certified, it’s after actually running thousands of hours of actual trials (including things like wing-destruct tests, v0, v1, v2 skidpad drag tests, and countless other tests). Rockets burn up every time we send them up, so if nothing goes wrong we breathe a sigh of relief and wonder how many items ALMOST failed, and if something does fail we (a) file the insurance claim, and (b) wonder how many items ALMOST failed that we don’t know about because the rocket burned up. Sure, there’s telemetry. But there’s no post-flight take it apart, test every widget, see how many are close to failure, where the wear/tear is occuring unplanned, metal fatigue, cracks in composites, etc. We can do individualised testing of components, then extrapolate.

    The problem is that we don’t know what we don’t know.

    This is why the DoD has to take front and center role in RLV technology development. That 1994 directive from President Clinton notwithstanding, ONLY the DoD has both the budget, and, vastly more importantly, the operational experience to run the rigorous levels of testing and missions/sorties required to properly vett a rocket.

    Then you get into a totally different Security discussion…. which should be saved for another day.

  11. Mike Snead said

    Thanks for this necessary and well warranted question. We need to be specific, don’t we?
    There are seven problems with current spacelift as it affects me, as the SBSP manager, and as the chief of Dream Works:

    1. It costs more than I would like to pay. In fact, launch cost seems to ruin the business case for many initiatives.
    Snead – This is the difference between an expendable-based transportation economy and a reusable-based transportation economy. I have searched, but I am unable to find any transportation system used on the Earth that is expendable. Shoes, climbing ropes, skateboards, cars, airplanes, trains, grocery carts, etc. Everything is reusable. This argues that expendable systems are contrary to good engineering and economic practices unless significant “driving” factors limit the ability of reusable systems to compete. I think it is clear that such circumstances exist in spacelift today.

    2. It takes too much lead time to plan for a lift.
    Snead – Again, this is a consequence of the expendable model. High cost drives out the design robustness needed to pack and ship payloads quickly. It’s also influenced by the lack of an integrated spacefaring infrastructure that enables payloads to space to processed and shipped to space and readied for on-orbit operation using standard practices and established in-space infrastructure. Think sea cargo delivery before containerized cargo vs. today. The standardization that will come with an integrated spacefaring infrastructure will reduce the lift time significantly to – hey, let’s fly next Tuesday.

    3. I have limited launch pads at limited launch ports, and too many rockets occupy pads for months–making a scheduling bottleneck.
    Snead – This is again the difference between the expendable munitions model and a fully-reusable space access system (note that I did not say an reusable expendable launch vehicle) that is designed, developed, produced, and operated using “aircraft-like” principles and practices. Time on the pad should be short – several hours for conventional propellants to a day if H2 is used and propellant tanks need to be thermally conditioned.

    4. I have to design everything not only for space, but for center of gravity, symmetrical balance, and G-loading during launch.
    Snead – This is no different than transporting cargo by aircraft. Crash loads are often a significant design requirement. With new transportation systems will come new payload design requirements/tools that integrate with the constraints of the transportation system.

    5. Lift is usually one-way…I can’t make a return trip.
    Snead – All reasonable reusable space access systems can be designed to return a payload. This is inherent with a flight abort capability. It is not easy – requires some finesse in the design to handle the c.g. shift as fuel is depleted and to also provide adequate thermal shielding of the payload on reentry if the payload is carried in an external cargo module.

    6. The market is over capacity and I am expected to share the wealth.

    7. Man-rating rockets is a long, hard, tedious, expensive process.
    Snead – There is no such thing as the “man-rating” of aircraft. Both civil and military aircraft are certified as airworthy prior to their release for operation. Airworthiness means that the design of the aircraft is shown by analysis, demonstration, and test to be sound and that each production aircraft is demonstrated by acceptance inspection and testing to have been built per the approved design. The military has a very clear process for defining the design requirements and demonstrating that the design requirements yield an airworthy aircraft. A similar process is used by the FAA.

    The basis of airworthiness is that this is the system that essentially replaces informed consent by the passengers and operating crew. It is impractical for passengers and crew to have sufficient detailed knowledge of the design of the aircraft and the specific condition of the aircraft they are to fly on to enable them to make an informed consent to accept the risk of flight. The goal of airworthiness is to ensure that the aircraft has a sufficiently low probability of loss that it is comparable to what the passengers and crew would experience and accept in normal living. (In fact, commercial aircraft are generally safer than the risk a person experiences daily.)

    “Man-rating” was a contrivance to imply something similar to airworthiness for expandable munitions adapted to carry astronauts. The true cost of man-rating expendable systems is far higher than establishing airworthy reusable space access systems. Just look at what happened to space launch when the Challenger and Columbia failed. Contrast this with is the last time we lost a commercial airliner.

    Establishing “airworthy” passenger space access is a cost and time burden that the nation must shoulder in order to become a true spacefaring nation.

  12. Edward Wright said

    c. The presentation implies that heavy spacelift will not be needed and that any 25K lb launch system will be adequate. This is incorrect from a cost point of view, from a flight rate point of view, and from a scale point of view. Expendable launch systems are far more costly than fully-reusable systems. The cross-over point is about 15-20 launches per year.

    Mike, 25K is heavy lift by FAA-AST definitions.

    Looking at a “cross-over point” based on subsidized, money-losing expendable vehicles is meaningless. If you want to understand how to operate an efficient transportation system, you can’t rely on “rocket scientists” like Koelle. You have to look at organizations that operate efficient transportation systems.

    How much money would Southwest Airlines lose if they bought at airplane, flew it 15-20 times a year, and parking it in the hangar the other 345-350 days?

    Airliners fly multiple flights per day. For orbital vehicles, launch window considerations are going to make it hard to fly more than once a day. Call it 5 flights a week, taking two days off.

    Allowing two weeks for annual maintenance, that’s 5 x 50 = 250 flights a year, but you can’t build a viable business on one vehicle. You need a fleet that’s large enough to allow to pick up the slack when one vehicle is done. For practical purposes, that’s at least four ships.

    So, the first “sweet spot” is at around 1000 flights a year. If you can’t fly 1000 flights a year, your vehicle is oversized for the market.

    If the initial space-based solar power systems will use terrestrially-fabricated units, as I expect would happen, then it would be appropriate to use a fully-reusable heavy spacelifter as costs always fall with scale.

    Correction: Cost scale only weakly with vehicle size. Compare a 747 and a 737. You won’t see great differences in efficiency. Cost scales strongly with flight rate. This is a result of the “learning curve” effect, a well-known industrial principle that’s unfortunately almost unknown among rocket scientists. 747s are efficient not because they are large but because they operate in a large, mature market where they can fly often.

    All the arguments made for heavy lift today were made before, at the beginning of World War II. It was argued that existing transports (specifically, the DC-3) were too small to support the coming war effort. Congress gave Howard Hughes a contract to build the Spruce Goose, which never flew during the war, but more than 10,000 DC-3 derivatives flew many millions of missions.

    The DC-3, by the way, had a *loaded weight* of only about 25K. Yet, it carried more supplies and supported the development of far more infrastructure than you will see on any space viewgraphs today.

    We don’t need to build a “Space Goose.” All we need is frequent, low-cost access to space.

    Such a system could come into operation by 2025 following a Shuttle-derived system (partially-reusable), with a comparable 80-100 ton payload capability, being brought into operation in 2016-2018.

    Flying only 15-20 times a year, such a system would cost nearly as much per flight as the Shuttle, not even considering the development costs. What’s the point?

    The only thing a superheavy lifter like that can do is reduce flight rates even further, distorting the market and pushing any reduction in launch costs farther into the future.

    I do not believe there is any question within the aerospace industry that (1) the U.S. can successfully develop near-term, fully-reusable, two-stage space access systems, and (2) that should such systems be developed using “aircraft-style” system engineering principles and practices leading to fully-reusable systems with “aircraft-like” safety and operability, then the recurring mission costs, compared with current costs, will fall dramatically.

    Actually, there’s considerable disagreement in the “aerospace community.” The whole justification for “Apollo on Steroids” is that “it’s the only thing that we know works.” Mike Griffin has stated his belief that NASA astronauts will be riding in space capsules launched on Ares rockets for the next 40 years.

    The late Dr. Max Hunter started his career working on the DC-4. He often bemoaned the fact that most space engineers had no such experience. They might talk about “aircraft-like” operations but don’t actually know what that means.

    Even the old German rocket scientists had little experience with aircraft. If you look at Von Braun’s drawings for manned successors to the V-2, the landing gear showed what can only be called rookie mistakes.

    So, I wouldn’t look for much from the mainstream “aerospace community.” Progress will come from new players and new markets.

  13. Edward Wright said

    3. I have limited launch pads at limited launch ports, and too many rockets occupy pads for months–making a scheduling bottleneck.

    If your goal to get to the launch pad or to get into orbit?

    The Naval Ordnance Test Center didn’t have any launch pads, but they launched NOTSNIK, which may have been the first US satellite to reach orbit. (Historians are still arguing about that — the center didn’t have good enough radar data to tell for sure.)

    Don’t limit your thinking to what “everybody does.”

    6. The market is over capacity and I am expected to share the wealth.

    Only the unmanned satellite market is over capacity. There are millions of self-loading carbon-based payloads for which there’s currently no transportation at all. And more can be produced by unskilled labor.

    7. Man-rating rockets is a long, hard, tedious, expensive process.

    Then don’t do it. Henry Spencer has pointed out that missiles tend to fail at roughly the same rate before and after they are man-rated.

    Missiles are unsafe whether man-rated or not. At best, they are about as reliable as an aircraft ejection seat (which pilots call “attempted suicide to avoid certain death”).

    Man-rating the expendable Atlas was a long, hard, tedious, expensive process but when Convair and Rocketdyne engineers set out to design a Reusable Atlas, they came up with development cost estimates that were similar to an aircraft, not a missile. The box is not your friend. Think outside the box.

  14. Mike Snead said

    Edward, perhaps you would like to explain what “aircraft-like” means to you based on your experience?

  15. Edward Wright said

    Edward, perhaps you would like to explain what “aircraft-like” means to you based on your experience?

    Mike, aircraft-like operations focus on “ilities” — reliability, maintainability, operability, saveability — rather than performance uber alles.

    To give you some examples:

    ELV guys will say they want reliability, but then they say “Atlas is pretty reliable.” If aircraft failed at the same rate Atlas does, no one would get on an airplane — and in the aircraft world, reliability means the crew, cargo, and airframe all return intact. In the missile world, they expect to lose the airframe on every flight. Even when they use the same words, they don’t mean the same thing.

    ELV guys will say the want fast response times, then boast about how they can prepare an Atlas for launch in only a few weeks. In the aircraft world, Southwest does 20-minute turns and the military does hot turns where the engine never stops running.

    ELV guys talk about ranges being overwhelmed if they have to do 12 launches a year and think scheduling two launches within a few days is a big deal. The US Navy can launch over a hundred airplanes in an Alpha strike.

    ELV guys think that putting an escape system on an Orion capsule solves all their safety problems. In the aircraft world, ejection is not the first option but the last resort, because pilots know it’s inherently dangerous — “attempted suicide to avoid certain death.” .

    ELV guys think they need to “seperate crew from cargo” and fly cargo on unmanned vehicles. Federal Express would never think of flying packages on an airplane that was so unreliable they were afraid to put a pilot on it.

    ELV guys think it’s more expensive to develop manned vehicles, based on a handful of data points (and ignoring data points like the X-15 that don’t fit the curve). Airplane guys know piloted vehicles are cheaper to develop than UAVs, based on a lot more datapoints. (Okay, maybe the Air Force doesn’t know that any more, due to a combination of marketing hype from the UAV guys and the messed-up nature of their manned aircraft procurement process.)

  16. Christine said

    Aircraft-like means a 12 hour turn time, the use of standardised payload canisters, and many many hundreds of reuses per airframe. Something like the Kankoh-Maru or DC-X.

    And unless you need a low G entry for high value biological cargo, wings on a space vehicle are moronic. The structure and heatshield covering it are useless in 99% of the flight regime, they decrease payload by > 50%, and the extra complexity drives up fabrication and servicing costs. Given the mass penalties involved with heatshielding, I suspect that an optimum reusable vehicle is going to be ballistic, vertically landing, and very, very large. Perhaps even Sea Dragon large.

  17. Edward Wright said

    Aircraft-like means a 12 hour turn time,

    If that were true, Southwest Airlines would be out of business.

    Some airliners on long-haul international routes might have 12-hour turn times but that’s due to scheduling windows (passengers don’t want to show up in the middle of the night), not because shorter turns are impossible.

    many hundreds of reuses per airframe

    For very large values of “many.” If airframes were designed for “hundreds of reuses,” planes would have to be replaced every few months.

    And unless you need a low G entry for high value biological cargo, wings on a space vehicle are moronic.

    “High value biological cargo” represents the largest market. Wings are also handy if you want to land at existing airports rather than spending millions or billions on new facilities.

    The structure and heatshield covering it are useless in 99% of the flight regime, they decrease payload by > 50%, and the extra complexity drives up fabrication and servicing costs.

    Airplanes carry many things that are not used 99% of the time. Landing gear. Doors. Lavatories. Fire extinguishers. First aid kits. Backup systems for almost everything.

    Unlike missiles, which are optimized for minimum weight, aircraft are optimized for minimum cost. They can afford to carry extra hardware because they don’t throw it away after one flight. Unlike missiles, which need to have “all systems green” for launch, airplanes have Minimum Equipment Lists and routinely take off with systems that are not working. They have enough redundancy to allow that.

    We need to start designing spacecraft instead of missiles.

  18. Edward Wright said

    Another comment on aircraft-like operations:

    I can’t remember who first said this, but there’s a saying that ELVs are designed to be flown by engineers and maintained by PhDs. Aircraft are designed to be flown by history majors and maintained by high-school graduates.

  19. Coyote said

    Ed Wright,

    \\**\\**

    (that’s how I do the Sammy Sosa salute to you via keyboard!) Minus the snideness, I think you got it about right.

    Coyote

  20. Raymond Neil Cox said

    Low lift cost, make solar power satellites more probable, but there are other concerns which we should address here, with miminal concern for the launch cost. 1 lowering the cost of the photovoltaic panels 2 lowering the cost of the rectennas 3 demonstrating with a pilot model that we have a correct grasp of the details. Does anyone have details of the pilot model Japan is planning? Does anyone have details of kystons producing millimeter waves. 10 millimeters is 30 gigahertz. One millimeter is 300 gigahertz = 300,000 megahertz = far infra red instead (perhaps) microwaves. Can we build a rectenna for one millimeter wave length? If yes. what will the rectenna cost per square kilometer? Neil

  21. Alex Gimarc said

    Coyote -

    I suppose I take exception with Slide 5 of the briefing – mostly because fossil (coal, oil and natural gas) and nukes are not fuel limited.

    Current limitations on fossil fuels are policy / legal only. We have enough of all three currently found within the existing US borders and offshore waters for hundreds of years. Include a substantial contribution of reactors for primary power to the busbar, and you can probably move that horizon out past a millenia – which ought to be far enough out there for the planners.

    Oil is a bit tight today, but the limitation is at the refinery level – “designer” blends of gasoline for the clean air act with a switchover in spring and autumn between summer and winter blends. It is a political problem with a political solution.

    Coal and natural gas are the two near-term energy resources after oil – and here in the US they are essentially unlimited in availability – even at current prices.

    Last reactor we built was 20+ years ago – mostly due to the fallout following TMI & Chernobyl. Yet the feds have 33+ licenses in process. As reactors are essentially unlimited in fuels – they can create their own fuels (breeders) – the reliability entry in SLide 5 for both nukes and fossil fuels need to be updated to reflect “Yes” as the proper answer. Cheers -

    – AG

  22. John Lee said

    Moderators: What does it take to get posted here; I know I haven’t broken the rules? This is the 6th attempt.

    Coyote said:
    <<So, you recommend spending whatever money we might get in solving all of the other problems–which seem far easier, to be quite frank–and simply be confident that if we make space-based solar power viable that the appropriate investors will resolve the launch frequency and cost problem for us.

    I know that I am not known by the group that has been posting here and for that reason may not be taken to seriously. It is, however, an open discussion, free to all to express their opinion. So, I feel compelled to express some very strong feelings that I have in this area.

    Coyote; if we are to follow the course summarized above, there are at least two assumptions we must make that I don’t think are certain:

    #1 We have to assume that SBSP or some other program will become to be of such a critical national priority that we will be willing to spend the billions required to research and develop a cheap reliable access to space. SBSP isn’t that critical now and I don’t believe it will be in the near future, except perhaps to the military. The reason I don’t think it will happen is that Land Based Solar Power is advancing as quickly if not quicker than SBSP. As an example: Nanosolar acquired an old Cisco plant in San Jose, Ca. at the beginning of the year to produce thin film solar cells. They will be printed in a roll to roll process with no silicon involved. At full production they expect to roll out 430 MW per year, and the cost, around $1/watt. In a good many areas the cost will compete well with the grid. I dare say, there are many millions of buildings in the US with black or very dark roofs; if we put solar panels on them we could convert 15 to 20% of the sunlight that strike them into electricity instead of heat. So, we won’t need big Solar Farms like the Wind Farms that have begun to appear in recent years.

    I think it unlikely that SBSP will provide power to the national grid, that just leaves the military to benefit from it’s use. Is it likely it will become critical enough for them to spend the money to develop cheap access to space in order to have it available for their purposes?

    #2 If I were writing the checks to fund research and development for the SBSP project, I think I would be very reluctant to approve money beyond basic proof of concept, if the proponents of the project can’t tell me how it will be deployed or how much it will cost. But, then, I’m not writing the checks; others may feel differently.

    If SBSP does not become a national priority, then 20-30 years from now we still won’t have a suitable access to space. But, wait, maybe there is a critical national priority that would justify the research and development dollars. There are at least a hundred perhaps more space missions or science missions that won’t be approved because they just don’t fit in the budget. None of these are of a critical nature alone, but together they represent not only a critical national priority, but a National Mandate to find a cheap, reliable access…

    There are several emerging technologies, that with full funding are candidates to provide the method we need to get up there. Some of these technologies will prove to be not ready yet, some will still be too expensive, but one or maybe two can be developed into just what we need.

    Coyote! Did you not say?

    1. Please forgive this editorial note, but I find it simply astonishing that in 2007 that we have not solved what has become the “age-old problem” of all spacefaring activities–access to the medium. In my humble opinion, this indicates a lack of strategic vision among nations to integrate space into our economic models.

    We can fault others for droping the ball, but we must not then refuse to carry it ourselves. We can’t just wait and see if the other fella will pick it up, because that’s exactly what he is doing too. Nearly every other post here has either said it or alluded to the fact that we need cheap access to space, why then should that not be the first recommendation out of all this discussion instead of the last. One small voice in the wilderness goes unheard, but hundreds spoken loudly and often will soon get the message across. This is too important to wait and hope someone else will do it.

    John

  23. Coyote said

    John,

    I don’t know why your comments have not made it to me for posting. In total, I have approved all but one or two comments sent to date–and those were in clear violation of the ground rules and common decency!

    There is no doubt in my mind that ground-based solar, wind, and nuclear energy will probably always be the easy solutions, but there are other capabilities that space-based solar power delivers that the others cannot. See my post of 18 July titled: “Space Solar Power: Much More Than Clean Energy,” I think that may answer some of your questions. Perhaps my posting of June 15th, “Crawl, Walk, Run: A Path to Space-Based Solar Power,” can also shed light on how we intend to bring this concept to reality.

    Solving the spacelift problem is #1 on the critical path list…as it is on every other space program as well. I totally agree that developing fleets of cost-effective, reliable, rapidly reusable spacelift vehicles should be a top priority!

    John…good comments…hopefully whatever was preventing you from posting is cleared-up. I look forward to more discussions with you!

    Coyote

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