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I posted about the XS-1 which Boeing is going forward with in the other space plane topic. There efforts are more in tune with military use and not for commercial venture.
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I didn't mean to say that there was no potential for intellectual property in spaceplane concept design. For supporting technologies and hardware items, there is plenty of room for such items. Unsolved issues include safe-and-reliable supersonic/hypersonic store-separation issues, fatally-destructive hypersonic shock-impingement heating, and plenty of unsolved propulsion problems.
XS-1 may or may not ever fly. Boeing makes more money turning these things into gravy-train technology items than by ever actually flying anything. Same is true for Lockheed-Martin. That is exactly what you get when you allow corporate agglomeration into a near-monopoly, aided and abetted by a government prejudiced against new entries into the business. That prejudice is made law and regulation by congressmen and senators and civil servants owned by these same giants.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Strictly speaking, spaceplanes are not interplanetary transportation. Who would send a lifting body or winged device to a place where there is no, or next to no atmosphere, A spaceplane is only useful to help get stuff to and from earth orbit.
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Elderflower is right to say spaceplanes (designed for Earth orbital flight) are not interplanetary vehicles. But they could be a link in a transportation chain that is interplanetary.
The kind of spacecraft design that makes a good orbit-to-orbit transport is entirely different from what makes a good Earthly spaceplane design, or what makes a good cargo rocket design, for that matter. What makes a good lander on Mars is distinct from what makes a good lander for the moon, or other airless bodies of noticeable gravity.
A proper transportation system very likely would use a mix of spaceplanes for two-way people transport and one-way cargo rockets to reach Earth orbit. From there people and goods transfer to the orbit-to-orbit transports for the long hop. A space station as a loading facility makes sense to make this happen.
At the destination world, you transfer once again to the landers appropriate to that world. A loading facility space station makes sense there, too. And the landers would be a mix of two-way transports and one-way cargo up-lifters for destinations off-world, just like at Earth.
What I have described is what a mature transportation infrastructure would look like, operating between Earth and colonies on other bodies. We don't start out looking like that. It grows over time.
GW
PS -- the obvious sanity of that design approach does apply to exploration schemes early on. If you stage out of LEO, you can use orbital assembly the create the orbit-to-orbit vehicles appropriate to the destination. These are smaller than in a mature system, but it's the same basic idea. It eliminates the need to waste time, effort, and resources on outsized rocket developments. All you need are things that can fling 10-50 tons to LEO.
What's different from the mature system is sending ahead unmanned other vehicles that are the exploration landers and the propellant supplies for them. Some of these can be used from local orbit, others could be emplaced directly upon the surface. The orbit-to-orbit transport IS your local staging-area space station.
This approach is specific enough not to waste resources, but general enough to be inherently adaptable to unexpected circumstances. It does require thinking way outside the Apollo box. More like what was contemplated in the early 1950's.
Last edited by GW Johnson (2017-05-29 10:10:18)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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GW-
I am in complete agreement regards using the orbital assembly of smaller loads for the deep space missions. My architectures posted elsewhere all use orbital assembly for facilitation of longer missions.
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Space planes would appear to have questionable usefulness. There is very little lift at sensible speeds above 100,000' and the air resistance heating at high Mach speeds is enormous. At Mach 6 it is above the melting point of aluminium at 100,000'. Mass ratios are inherently poor, the air frame would have limited reusability and the thermal protection would add weight and require refurbishment between flights. The space plane is limited to being a lower stage (out of 2-3 stages) and is a technically difficult one at that.
There does not seem to be much that a space plane can do that a reusable pressure-fed LOX/Propane lower stage could not. For smaller stages a simple drag chute could slow it to acceptable terminal velocity for an ocean splashdown. Tow it back to port, refill and reuse. The trick is to make it rugged and simple.
Last edited by Antius (2017-06-02 08:38:14)
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Antius:
I quite agree that spaceplanes are of limited usefulness, as long as we are limited to current propulsion methods. I did a bounding analysis for single-stage spaceplane operation that showed we will need at least gas core nuclear light-bulb engine technology to make them truly attractive at reasonable mass ratios and payload fractions. If multistage (inherent with weaker propulsion), they will never be very attractive.
That being said, very small multi-stage or booster-launched spaceplanes might be useful for transferring small crews or critical small items to and from orbit as short-notice, land-anywhere items, where cost is little or no object. Otherwise, spaceplanes will be unattractive as bulk cargo carriers until we have very much better propulsion, as our experience with the shuttle so clearly indicated.
The thing that clouds this picture is Spacex with their propulsive pin-point landing scheme for crewed Dragon. That pretty much gives to the space capsule a land-anywhere on dry land capability while avoiding having to pay a fleet of ships to pick it up out of the ocean.
With the recoverable fly-back booster technology reducing costs even further than logistical simplification did, this option is getting very attractive indeed. If it fully proves out, there is little need for a rocket-boosted or multistage small spaceplane for small crews: the capsule can do that job easier and cheaper if it really can pin-point land on dry land.
As for ocean recovery of spent stages, NASA experienced high impact damage rates with shuttle SRB's. It's hard to slow a stage below 20 mph to avoid this; faster, and you might as well hit rock as water. And that was with heavy solid rocket construction. Lighter-weight liquid-propellant stages are even more fragile. That's where the Spacex first stage fly-back-to-a-propulsive-landing technology has been such a technical breakthrough, enabling a cost breakthrough.
Heat protection of exposed skins depends upon whether they are cooled in some manner. Aluminum skins on aircraft are shiny, and do not radiate very well at all. Accordingly, steady-state they soak out to approximately the air stream recovery temperature, which is almost (but not quite) the total (or stagnation) temperature, easily figured with ideal gas methods to about Mach 6. Above that speed, the actual or effective temperature in deg K is roughly numerically the same as flight velocity in meters/second, but it ain't air anymore. More and more of the kinetic energy goes into dissociation/ionization as you fly faster than that.
Aluminum melts between 900 and 1000 F, but is worthless structurally above about 300 F. The data in Mil Handbook 5 support that assessment. In a standard day atmosphere, above the tropopause, 300 F corresponds roughly to Mach 2.2 flight. That's why no aluminum-skinned fighter plane has sustained dash speeds above Mach 2.2. On brief transients, you can heat-sink your way through a short dash to about Mach 2.5 or so, but that's just about the limit with aluminum.
People seem to think titanium is a miracle: lighter than steel, and able to take heat. It is not a miracle. Density is between aluminum and steel, but its heat resistance (according to Mil Handbook 5) is no better than mild carbon steel: about 750 F. For non-radiating shiny finish, you hit that limit at about Mach 3.2 in the stratosphere, but at lower speeds lower down, and higher up, where the air is warmer. If you can successfully blacken the finish for efficient re-radiation, you can fly a bit faster, because it will equilibriate at a lower temperature than recovery soak-out. This was successfully done to achieve Mach 3.3 flight at 85,000 feet with the SR-71 and its variants.
To go faster still, you must accept the higher densities of the steels and the superalloys. 300-series stainless steels can be routinely exposed to about 1200 F, with a few that will go higher at 1600 F. As shiny surfaces soaked out to recovery temperatures, that's about Mach 4 in the stratosphere at 1200 F, and Mach 4.6 in the stratosphere at 1600 F. The Inconels have similar recommended max use temperatures: around 1500 F or so. Even the superalloys are junk by 2000 F or so.
To go any faster than that, you must blacken the finish and cool it by radiation. If the emissivity is around 0.90, you can maintain 1600 F skin equilibrium at about Mach 6, where the recovery temperatures are nearer 3000 F. That can be done with SS 316, 309, and 310, or the Inconels and superalloys.
SS 316 is actually readily available and not super expensive. The more common SS 304 is limited to 1200 F. You cannot go so fast with it. The X-15 with blackened Inconel-X skins survived flight up to Mach 6-ish and 100,000 feet. One flight suffered nearly-fatal shock-impingement heating damage at Mach 6.7, but that had to do with a payload it carried on its ventral fin stub.
The superalloys might offer slightly-better resistance to heating, but are hugely expensive, and even harder to work than the Inconels,
already very much harder to work than the steels.
To go any faster than that rough Mach 6-ish speed requires some sort of metallic or ceramic heat protection tiles or similar heat shield "armor". You're actually better off flying outside the atmosphere than trying to cruise steady state that fast down in the sensible air. Solving the space launch propulsion problem is actually easier than solving the heat protection problem.
For vertical-launch ballistic space launch, you usually leave the sensible air around 100,000 feet and Mach 2-ish, which almost entirely avoids most of the ascent heating. This is inherent, because of launch gee limitations for practical payloads. It is upon reentry that heating is the dominant issue.
Generally speaking, the need to fly hypersonic (Mach 4 to about Mach 8) down in the sensible air (below about 125,000 feet) is more associated with missile work than with space flight launch work, or any sort of practical aircraft work. There are many who do not want to face that, but it is still true. Ugly little facts of life.
GW
Last edited by GW Johnson (2017-06-03 11:24:16)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Seems then that the Dreamchaser is the extent of a semi plane ship to orbit and that we should forget about them for larger payloads than a crew taxi....
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An analogy I like is to the offshore oil industry platforms. The crews rotate by helicopter but all the big, heavy stuff goes by surface ships. Similarly, the only use I would see for spaceplanes is for quick, simple access to LEO and return for crews and light items. The bulk of the orbited mass is going to stay with old fashioned multi stage rockets.
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I would agree with the assessments of Spacenut in post 33 and Elderflower in post 34. That will be true until there is available very much hotter propulsion than is available today.
We need something with an Isp > 1500 sec (>2000+ preferred) and an engine thrust/weight > 30, plus a clean (nonradioactive) exhaust stream. That 1500 sec Isp at high thrust will get you a single stage vehicle with a payload fraction of maybe 8%.
To look more like an airliner's payload fraction, you need Isp > 4000 sec at very high T/Wengine. Pulse propulsion could do that, except that its exhaust is very radioactive.
GW
Last edited by GW Johnson (2017-06-04 15:23:43)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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ISP x thrust = power. An isp of 4000 and t/w of 30 is a lot of power. In terms of storable propellant, isp 4000 equals a propellant energy density of 270MJ/kg. That's 27 times lox/kerosene. This is beyond the energy density of any known chemical propellant. And it is difficult to design a device that can transfer that sort of thermal energy to a propellant whilst remaining physically intact. Hence the need for bomb driven propulsion.
Another option for SSTO is the sky hook. The vehicle reaches some fraction of orbital velocity and intercepts the end of an orbital tether.
Last edited by Antius (2017-06-04 16:29:48)
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I don't think there is much in the way of intellectual property to be claimed here. There have been spaceplane proposals since the 1940's, and they got serious about it in the 1950's with the X-20 Dyna-Soar project, cancelled in 1963 with the first 3 test craft coming off the production line. Horizontal takeoff staged spaceplanes were studied as part of the definition of the Space Shuttle in the late '60's into the early 70's, when the design approach pretty much "froze".
The latest is the notion of the horizontal takeoff rocket airplane as first stage for a rocket-as-payload released above the sensible atmosphere. The civilian versions are the XCOR "Lynx" and the Virgin Galactic "Spaceship Two". The military version is the XS-1 that DARPA just gave to Boeing this week. XS-1 is Boeing's attempt to steal XCOR's approach, just in an craft the size of a business jet instead of a light airplane.
Note that none of these are large craft, and none of these are aimed at anything beyond orbit. What is the point of taking wings you cannot use to the moon or anywhere else? Wings might be made to work at Mars, but because that "air" is so thin, the airplane that works there will be nothing like any airplane that works here.
What these concepts have in common, except for Shuttle, is that the craft were small, intended to deliver people and and their luggage. Cargo is best delivered vertical launch in an expendable or semi-expendable rocket. If you can recover and reuse first stages, so much the better. But prices have already dropped dramatically due to reductions in the sizes of support populations, even without reusability at all.
GW
At the moment, I've done some additional search of already known spaceplane designs, which could became a prior art for my project. Still, I hadn't found any prior art that would be killing; although some of other designs, probably, would even reach low Earth orbit, anyway my project is much better, compared to others, if we take into account minimal price per kilogram on LEO, maximal possible cargo weight on LEO, and convenience of use.
Also, taking into account the stratagem by which the Russians were already trying to plagiarize my inventions (they bluntly promised to "find" some very old items, probably from 1950 or so, in secret museums of their design bureau, which would be identical to my inventions - of course, forgeries), I would be very interested whether it would be possible to examine all the other designs, competing with my spacecraft projects, to prove if they are genuine and not forgeries. If I can prove my authorship and priority under a lie detector (as it was declared by me earlier), so whether it would be possible for my competitors to prove their authorship and priority in the same way?
Concerning the claims of my intellectual property - probably, it would be too soon to provide here a complete set of my formal claims, something like my patent filings; it's not excluded that I would do that later, but maybe, I could convince you that I have invented quite new and non - obvious things, if I'd only mentioned, that my design of spaceplane opens the possibility for humans to visit Moon, Mars, asteroids, and return back on Earth, on completely reusable non - nuclear universal spaceships (the same spaceship modules could earn money placing commercial satellites on all Earth orbits, or complete some military missions, or be engaged for trip to Moon, or Mars, or asteroids: additionally, only landing modules for visiting of Moon and Mars are needed); the possibility that I've never seen before in any other projects, and which, therefore, is not only my intellectual property, but also it is my scientific priority.
Theoretical possibility to fly (nearly) to any place, on the same, completely reusable spaceship, is significant, because the working life of the technical device could be made much longer, as the progress of technologies goes (no need to buy a new car for every new trip, and no need to have a different car for a trip to different place). The only thing which is still needed becomes only fuel/oxidizer, but they are cheap. That way, my project is somewhat significant step, I dare say.
The possibility to use the regular (non - nuclear) engines is also very significant, because using of nuclear rocket engine (like NERVA) seems not only very expensive, but also dangerous. Let's remember, Challenger blew up climbing into orbit, Columbia on reentry; if they were nuclear, it would be a major disaster, something a kind of Chernobyl catastrophe. It's not a good feeling, if winged Chernobyl reactor is flying right up over your head. But, it's not excluded they would be still implemented, who knows.
[On a hint from my team: if we're talking about nuclear rockets, like NERVA, it would be interesting to imagine, just for interest, how we could implement this project of three - staged spaceplane with nuclear thermal rocket engine. Let's imagine that the third stage (spaceship) is equipped by such a nuclear rocket engine, everything else is nearly the same, only tanks for rocket fuel/oxidizer from the second and the third stages are changed by tanks for nuclear engine propellant. So, what we could obtain from that? Nothing interesting, if the propellant is hydrogen; but something very attractive, if the propellant is water. Because if the propellant is water, we could use the same multiple and multistaged refuelings, as when we used ordinary fuel/oxidizer; but also, we could use a possibility to obtain water from asteroids, where it is easily accessible in a form of ice (I invented using of water as a propellant for nuclear electric rocket engines, in order to made possible obtaining of the propellant from ice on asteroids, about 1999, that became known to others in 2005; unfortunately it didn't came to my mind to use nuclear thermal rocket engine, like NERVA, for such purpose; nuclear electric rocket engines have much weaker thrust, but much greater impulse, so they seemed to be optimal for long interplanetary trips). That way, by using of water as a propellant, possibly from asteroids, and with all that refuelings, it become possible to conquer the whole Solar System, on a spaceships that are very implementable by the known technologies. Maybe one could ask, what is the use of that three - staged design of my spaceplane, when using nuclear thermal rocket engine? Practically, it would be very beneficial, because all the thing become much more realistic. NERVA has impulse about 800 sec. in vacuum, but much less in atmosphere, and more significantly, using of water instead of hydrogen as a propellant made the impulse still less. Also, if we use nuclear engine, we need to provide a radiation shield for a crew; and maximizing of real (not theoretical) impulse of nuclear thermal rocket engine would greatly affect it's reliability, and we would probably better stay with engine having less impulse (if only it would be enough to reach LEO), but with better reliability (we don't want that nuclear engine to blew up from one small grain of sand in the propellant, so the reliability is very important). That way, engine impulse and mass efficiency would be not enough for SSTO - and for 2STO, either. But if we use my three - staged design, with turbojets on a first stage, and ramjets on a second stage - it seems, we could reach LEO even on the currently implementable nuclear thermal rocket engines for a third stage (spaceship), with water as a propellant; and than, as far as low Earth orbit is reached, we could use multistaged refuelings, than fly higher and higher, than reach asteroids, obtain water from ice for propellant, and travel all over the whole Solar System.]
Last edited by Yuri Pilipishin (2017-06-05 17:03:42)
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Strictly speaking, spaceplanes are not interplanetary transportation. Who would send a lifting body or winged device to a place where there is no, or next to no atmosphere, A spaceplane is only useful to help get stuff to and from earth orbit.
If reusable spaceship returns to Earth from interplanetary trip, it could use the same wings and thermal protection to slow down its interplanetary velocity, in order to came up to circular Earth orbit, or even land. If there is no wings and thermal protection, it's needed to use engines, burning fuel, and the needed fuel might weight even more than those wings and thermal protection (and fuel burns, when wings and thermal protection are reusable). Overthrowing of this inertion of thinking, the old apporoach which evolved with non - reusable rockets, is a subject of my invention.
Last edited by Yuri Pilipishin (2017-06-05 16:56:34)
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[On a hint from my team: if we're talking about nuclear rockets, like NERVA, it would be interesting to imagine, just for interest, how we could implement this project of three - staged spaceplane with nuclear thermal rocket engine. Let's imagine that the third stage (spaceship) is equipped by such a nuclear rocket engine, everything else is nearly the same, only tanks for rocket fuel/oxidizer from the second and the third stages are changed by tanks for nuclear engine propellant. So, what we could obtain from that? Nothing interesting, if the propellant is hydrogen; but something very attractive, if the propellant is water. Because if the propellant is water, we could use the same multiple and multistaged refuelings, as when we used ordinary fuel/oxidizer; but also, we could use a possibility to obtain water from asteroids, where it is easily accessible in a form of ice (I invented using of water as a propellant for nuclear electric rocket engines, in order to made possible obtaining of the propellant from ice on asteroids, about 1999, that became known to others in 2005; unfortunately it didn't came to my mind to use nuclear thermal rocket engine, like NERVA, for such purpose; nuclear electric rocket engines have much weaker thrust, but much greater impulse, so they seemed to be optimal for long interplanetary trips). That way, by using of water as a propellant, possibly from asteroids, and with all that refuelings, it become possible to conquer the whole Solar System, on a spaceships that are very implementable by the known technologies. Maybe one could ask, what is the use of that three - staged design of my spaceplane, when using nuclear thermal rocket engine? Practically, it would be very beneficial, because all the thing become much more realistic. NERVA has impulse about 800 sec. in vacuum, but much less in atmosphere, and more significantly, using of water instead of hydrogen as a propellant made the impulse still less. Also, if we use nuclear engine, we need to provide a radiation shield for a crew; and maximizing of real (not theoretical) impulse of nuclear thermal rocket engine would greatly affect it's reliability, and we would probably better stay with engine having less impulse (if only it would be enough to reach LEO), but with better reliability (we don't want that nuclear engine to blew up from one small grain of sand in the propellant, so the reliability is very important). That way, engine impulse and mass efficiency would be not enough for SSTO - and for 2STO, either. But if we use my three - staged design, with turbojets on a first stage, and ramjets on a second stage - it seems, we could reach LEO even on the currently implementable nuclear thermal rocket engines for a third stage (spaceship), with water as a propellant; and than, as far as low Earth orbit is reached, we could use multistaged refuelings, than fly higher and higher, than reach asteroids, obtain water from ice for propellant, and travel all over the whole Solar System.]
One more idea, on a hint from my team - to try to implement a combined nuclear thermal/electric rocket engine; with the same water for a propellant; using it in the said spaceship (third stage of my spaceplane). Reactor provides heat; we could use the heat to evaporate water (thermal rocket), or to generate electricity and than use electricity in electric rocket engine (accelerating ions of hydrogen and oxygen to very high velocities). This is not easy to implement, but seems still possible, on the present level of technology. That way, with the same source of energy (nuclear reactor) and propellant (water), we could use two different ways of generating thrust: for maneuvers with high acceleration (nuclear thermal rocket), and for long time interplanetary trips (nuclear electric rocket). And also, wings and thermal protection seems very useful: it becomes possible to accomplish maneuvers in atmospheres of many different planets/moons: not only Mars, but probably Titan, and some other. Of course, key possibiliies of multiple and multistaged refuelings of propellant, and obtaining water from ice on asteroids, still are important; but also, using of electric acceleration for long interplanetary trips is much more effective, and also, anyway we need to get electricity from reactor, in order to electrolyze water to obtain oxygen for a crew. This idea could give us, probably, the best universal interplanetary spaceship, being implementable on the present level of technology.
Last edited by Yuri Pilipishin (2017-06-06 04:45:24)
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Aluminum melts between 900 and 1000 F, but is worthless structurally above about 300 F. The data in Mil Handbook 5 support that assessment. In a standard day atmosphere, above the tropopause, 300 F corresponds roughly to Mach 2.2 flight. That's why no aluminum-skinned fighter plane has sustained dash speeds above Mach 2.2. On brief transients, you can heat-sink your way through a short dash to about Mach 2.5 or so, but that's just about the limit with aluminum.
People seem to think titanium is a miracle: lighter than steel, and able to take heat. It is not a miracle. Density is between aluminum and steel, but its heat resistance (according to Mil Handbook 5) is no better than mild carbon steel: about 750 F. For non-radiating shiny finish, you hit that limit at about Mach 3.2 in the stratosphere, but at lower speeds lower down, and higher up, where the air is warmer. If you can successfully blacken the finish for efficient re-radiation, you can fly a bit faster, because it will equilibriate at a lower temperature than recovery soak-out. This was successfully done to achieve Mach 3.3 flight at 85,000 feet with the SR-71 and its variants.
To go faster still, you must accept the higher densities of the steels and the superalloys. 300-series stainless steels can be routinely exposed to about 1200 F, with a few that will go higher at 1600 F. As shiny surfaces soaked out to recovery temperatures, that's about Mach 4 in the stratosphere at 1200 F, and Mach 4.6 in the stratosphere at 1600 F. The Inconels have similar recommended max use temperatures: around 1500 F or so. Even the superalloys are junk by 2000 F or so.
To go any faster than that, you must blacken the finish and cool it by radiation. If the emissivity is around 0.90, you can maintain 1600 F skin equilibrium at about Mach 6, where the recovery temperatures are nearer 3000 F. That can be done with SS 316, 309, and 310, or the Inconels and superalloys.
Heating when climbing into orbit really could be some problem, but seems it could be solved. As I had already written, we could use a leading edge of the big delta wing, being cooled by flow of fuel/oxidizer, pumped through its inner channels. Of course, the second stage should be implemented as hot airframe, also in order to not be damaged on reentry (probably made from heat proof steel or heat resistant composites, surely not aluminium). But also (for my spaceplane) it's not needed to fly faster than M5 - M6 in air, to reach orbit. It climbs on an altitude about 100km with those M5 - M6 (about 1.5 km/sec, ramjets + rocket), and only after the second stage is separated, obtains these last 6.5 km/sec, when flying above 100 km, where is no air.
Last edited by Yuri Pilipishin (2017-06-06 06:06:13)
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Yuri:
As I said in a previous post, I doubt there's much in the way of overall staged spaceplane configurations that is patentable, but there's still a bunch of ways-and-means technologies that would be patentable. You won't know until you do the patent search.
Wings are good for landing at subsonic speeds, and for cross range and alternate site work after reentry is over. They are vulnerable during reentry, and they are dead weight during final ascent to orbit. If you launch vertically, they are dead weight all during ascent. If you launch horizontally, they are useful for takeoff, but your flight path is depressed into the atmosphere much longer for higher speeds, which eats up much of your propulsive energy as drag losses.
After you leave orbit wings are dead weight period. Wings that work at Earth will not work at Mars, and vice versa. Nowhere else to go has any use for wings except maybe Titan. So, why take a winged craft out of Earth orbit? It seems rather pointless, given the tyranny of the rocket equation.
Likewise, the kind of life support needed for long duration spaceflight is heavy, and unnecessary for travel between the surface and Earth orbit (very short term spaceflight). Why burden a spaceplane trying to reach orbit with that kind of dead weight to carry? That also seems pointless.
Those considerations are why I recommend that the vehicles which do surface-to-orbit-and-back be entirely separate designs from the vehicles that go places outside of Earth orbit. Most of the actual design proposals since the 1940's reflect that, too. It is only in the fictional movies that space shuttle-like vehicles are shown flying to other places than low Earth orbit. Because script writers are not rocket engineers and don’t know any better.
It is possible to build a single-stage spaceplane-like craft with a decent-enough payload fraction ~10% to be economically attractive relative to simple launch rockets, but not with any propulsion we have today! You have to do a 2 or 3-stage spaceplane, which for a given payload, becomes truly monstrous on size, which defeats any economic utility.
What makes the single-stage work is propulsion with Isp exceeding 1500 sec but very high engine thrust/weight > 30. The old NERVA was about 900 sec Isp at engine T/W ~ 4. Doesn't qualify. The things we know of that might qualify are gas core nuclear thermal technologies, and nuclear pulse propulsion. None were ever built and tested, although the physics at least says pulse propulsion will work.
Gas core open cycle and pulse propulsion have very radioactive exhausts, which make them practically unacceptable for the Earth launch job. Closed-cycle "nuclear light bulb" gas core technology has a clean exhaust, and might possibly be developed to reach the performance levels needed to make a single-stage, airliner-like spaceplane feasible. Projections unsupported by any test data said Isp 1300-1500 sec was possible, and engine T/W might exceed 10. The operative word there is "might". Even today, such engines are still nothing but science fiction.
Once you start staging your spaceplane to compensate for the weaker available propulsion, you end up in the same tail-chase of massive launch weight (cost) and low delivered payload fraction (even more cost) that made the US Space Shuttle and the Soviet "Buran" space shuttle unattractive. The US shuttle put a 100 ton spaceplane in orbit to deliver 15 tons of supplies, with a launch weight near 2000 tons. That’s under 1% deliverable payload fraction. It cost about $1-1.5B to launch. That's $60-100M/ton.
Compare that with the kinds of prices in the competitive satellite launch business today, even with expendable rockets. That's around $5-6M/ton in sizes between 5 and 20 tons. That’s an order of magnitude lower than shuttle. It's about to fall to half that value with 50 ton capability soon (there is a slight beneficial effect of larger sizes). Reusability of some parts of the rockets promises to reduce that still further.
Honestly, I don't see much advantage to pursuing a multi-stage spaceplane. I would see an advantage to pursuing the advanced propulsion needed to make a single-stage spaceplane feasible. I definitely see advantages to pursuing lower cost one-way rockets to orbit, and capsules to come home in. Use them to assemble your deep space craft in orbit, and base those deep space craft out of orbit.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Wings are good for landing at subsonic speeds, and for cross range and alternate site work after reentry is over. They are vulnerable during reentry, and they are dead weight during final ascent to orbit. If you launch vertically, they are dead weight all during ascent. If you launch horizontally, they are useful for takeoff, but your flight path is depressed into the atmosphere much longer for higher speeds, which eats up much of your propulsive energy as drag losses.
It only means, that winged spaceplanes are suitable for air-breathing engines: turbojet for altitudes 0 - 25km; and ramjets for altitudes 25 - 50km, and even higher for some auxiliary additional thrust. That way, we maximally use oxygen from atmosphere. Also, wings are useful, as thrust of air-breathing engines often is less than a mass of the apparatus: in that case, wings permit ascent for a gentle slope, instead of a vertical uplift.
After you leave orbit wings are dead weight period. Wings that work at Earth will not work at Mars, and vice versa. Nowhere else to go has any use for wings except maybe Titan. So, why take a winged craft out of Earth orbit? It seems rather pointless, given the tyranny of the rocket equation.
Ok, then let me demonstrate you the said tyranny of the rocket equation.
Let's presume, we have some reusable interplanetary spacecraft with an ordinary (chemical, with burning fuel/oxidizer) rocket engines. What's going on, if we return to Earth from some interplanetary trip? We need to slow down its interplanetary velocity (not less than 11.2 km/sec) in order to transfer to a circular low Earth orbit (about 8 km/sec). That way, if we use engines for this maneuver, we need to (reverse) accelerate our spaceship not less than 3.2 km/sec (and this is only minimal estimate). Let's presume, we use a very good non-cryogenic fuel with I = 3.8 km/sec. What mass of fuel/oxidizer, as compared with the final mass of the spaceship, should be used?
It's simple.
V = I*ln(M1/M2) -> ln(M1/M2) = V/I -> M1/M2 = exp(V/I)
That way, M1/M2 = exp(3.2/3.8) = 2.321
This means, in order to slow down our reusable spaceship from interplanetary velocity to orbital (LEO) velocity, we'd need to use a mass of fuel/oxidizer of more than a whole final mass of our spaceship. And we'd need to carry all that fuel, needed to final slow down before transfering to LEO, on all the way of our interplaneary trip (and this is for not such a long interplanetary trip: on the Moon or nearest asteroids; for trip to Mars or more distant asteroids, it's even more).
And so, wouldn't it be better, if instead of using fuel/oxidizer, in order to slow down from interplanetary velocity, we'd use an atmospherical maneuver? These wings and thermal protection, needed for such an atmospherical maneuver, wouldn't weight as much as the fuel/oxidizer, needed for the similar slow down (and even more: they are reusable, while fuel/oxidizer burns out)!
This is a plain demonstration, why wings/thermal protection are useful for interplanetary travel. As far as we use ordinary engines, with their small impulse, using of atmospherical maneuvers when returning to Earth is beneficial, even if we'd count a mass efficiency (not to say, wings/thermal protection are reusable, while fuel should be carried to orbit again and again, which is more expensive).
But even more: these wings/thermal protection could be used also for atmospherical maneuvers on other planets, first of all - Mars. Of course, I don't say we should fly on our spaceship (third stage of my spaceplane) in Martian atmosphere like on an aircraft. I meant, we could use the same atmospherical maneuver in upper layers of Martian atmosphere, in order to slow down our spaceship from interplanetary velocity, and to transfer to low Martian orbit with minimal use of fuel/oxidizer. That way, on interplanetary trip to Mars, wings/thermal protection become even more useful: we use them to slow down twice, when arriving to Mars and when returning to Earth (and this is exactly the method, by which we could refuel spaceships by tankers on Martian orbit: from a very high Earth orbit, we send to Mars a chain of completely refueled tankers, which slow down by Martian atmosphere and then transfer to low Martian orbit, there give a bit of their fuel/oxidizer to a Martian spaceship or Martian landing module, and use the rest of fuel/oxidizer to return to Earth; of course, these tankers should have a very good mass efficiency, to accomplish such a trick).
Also, we could sometimes use atmospherical maneuvers in atmosphere of Venus, slowing down our spaceship on fly-by, if it is needed for some reason.
That way, there are three types of maneuvers we could accomplish:
1. Engine maneuvers
2. Gravitational maneuvers
3. Atmospherical maneuvers
Combining them all, and using the said multiple and multistaged refuelings, we could accomplish rather a complicated interplanetary pilotage.
(After reading all those ideas, probably you'll agree that there is quite a something to claim as intellectual property, in my project.)
Likewise, the kind of life support needed for long duration spaceflight is heavy, and unnecessary for travel between the surface and Earth orbit (very short term spaceflight). Why burden a spaceplane trying to reach orbit with that kind of dead weight to carry? That also seems pointless.
Universal cargo spaceship (the first, and probably the most oftenly used variant of the third stage of my spaceplane) only has an empty universal cargo bay. When carrying satellites on LEO, it would contain that cargo; when the spaceship is used for maintaining satellites on orbit, it would contain a small capsule for a crew, and all the instruments needed to maintain satellites (a manipulator arm, a rocket backpack, etc.); when the spaceship is used for interplanetary travel, it would contain a specialized living module with all the needed facilities for a long duration spaceflight; and so on.
Those considerations are why I recommend that the vehicles which do surface-to-orbit-and-back be entirely separate designs from the vehicles that go places outside of Earth orbit. Most of the actual design proposals since the 1940's reflect that, too. It is only in the fictional movies that space shuttle-like vehicles are shown flying to other places than low Earth orbit. Because script writers are not rocket engineers and don’t know any better.
Of course, I know about orbital assembly; in fact, one thing that I had invented for my spaceplane, was orbital assembly from blocks delivered to orbit by it, of a big interplanetary spaceship with nuclear reactor and electric engines. As far as I know at the moment, there is nothing especially new in this idea, except the propellant: I invented to use water as a propellant for its electric engines. It seems less effective as compared with using of heavy neutral gases like crypton; but instead, with water as a propellant we could use water ice from asteroids to get new propellent; and also, the water and the oxygen electrolized from it could be consumed by crew.
That way, we would got the really independent spaceship, able to fly here and there across the whole Solar System. And, as soon as we could get such a really independent interplanetary spaceship, I invented a military use of it: this spaceship could be used for a long-range bombardment of Earth (or, very precisely appointed places on Earth) by nuclear (thermonuclear) bombs. The bombs are directed by spaceship to Earth from a very long distance, probably from asteroid belt. After the bomb is guided on its traectory, the spaceship turns aside by its engines, and hide in asteroid belt; that way, the spaceship stays invisible and unreachable from Earth; and the bomb itself could be done stealth, staying invisible all the way to Earth. That way, the only possibility to defend itself from such spaceships would be to create the similar spaceships, hunting for one another in deep space, probably in asteroid belt, or in ring of Saturn, etc.: there is lots of space to hide in the whole Solar System (it's needed to add, this project is also my intellectual property, which I could prove by a modern variant of a lie detector, in a way that I have already mentioned).
That way, you can see, I know even better than script writers: if I would write the script, our Ukrainian spaceships would bombard the frightened Moscow by thermonuclear bombs, safely hiding themselves in asteroid belt or ring of Saturn, and giving no mercy to our enemies
But, in real world, implementing of nuclear reactor in space is costly, and also not safe (what if it fall down to Earth? it'll became dirty nuclear bomb). That way, this is rather not possible for private space company (too much troubles with IAEA, etc.); using of ordinary fuel, and multiple / multistaged refueling, seems cheaper and better, at least for not-so-distant interplanetary travels: to Moon and asteroids, and maybe Mars.
Last edited by Yuri Pilipishin (2017-06-19 10:17:22)
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It is possible to build a single-stage spaceplane-like craft with a decent-enough payload fraction ~10% to be economically attractive relative to simple launch rockets, but not with any propulsion we have today! You have to do a 2 or 3-stage spaceplane, which for a given payload, becomes truly monstrous on size, which defeats any economic utility.
I don't know any single- or two-staged completely reusable HTHL spaceplane design, being able to reach orbit at the present level of technology. Among 3STO HTHL designs that I have seen, my design seems the best: providing the best price and mass-to-orbit payload fraction, and also with reasonable size of the thing. I wouldn't say my spaceplane is monstrous: for example, if we implement this design with a first-stage engines of Tu-144, the size of the thing would be similar to size of Tu-144, either, with about 200 ton of takeoff weight - and bringing to orbit not less that 1.5 - 2 ton of cargo. This is quite a realistic estimate, not adverticement. I'd say, as compared with a traditional rocket for the same payload, and especially with all the needed launchpad facilities, it is by far not monstrous. And if we'd increase the thing to 5 ton of cargo, it would become only about 1.5 times larger - which is also not monstrous, fit for standard hangars and runways, etc.
What makes the single-stage work is propulsion with Isp exceeding 1500 sec but very high engine thrust/weight > 30. The old NERVA was about 900 sec Isp at engine T/W ~ 4. Doesn't qualify. The things we know of that might qualify are gas core nuclear thermal technologies, and nuclear pulse propulsion. None were ever built and tested, although the physics at least says pulse propulsion will work.
I don't know real characheristics of NERVA, all those works were highly classified. The information that I could obtain from open sources about Soviet program of nuclear thermal rocket engines, says they were slightly better (the same engine created by Valentin Glushko, that is discussed in neighbor topic). Again, if we change the rocket engine of the third stage of my spaceplane by nuclear thermal(+electric) engine, it wouldn't need to be so much sophisticated, with enormous Isp, etc.: as far as we have 3STO design, the demands to nuclear engine of the third stage would be moderate. The reasons to use nuclear propulsion are different: not for SSTO, but to use water as a propellant, making possible long-range interplanetary flights with obtaining water on asteroids.
Gas core open cycle and pulse propulsion have very radioactive exhausts, which make them practically unacceptable for the Earth launch job. Closed-cycle "nuclear light bulb" gas core technology has a clean exhaust, and might possibly be developed to reach the performance levels needed to make a single-stage, airliner-like spaceplane feasible. Projections unsupported by any test data said Isp 1300-1500 sec was possible, and engine T/W might exceed 10. The operative word there is "might". Even today, such engines are still nothing but science fiction.
Even if some day nuclear engines would be able to provide a propulsion, good enough for SSTO, they still are too dangerous and expensive. Even if exhaust is clean - what if a catastrophe occured? Not even to mention cases of Challeneger and Columbia: we all know that ordinary airplanes are sometimes dangerous, and catastrophes of airplanes happen. This is, by the way, the cause why there was no real nuclear airplanes implemented - although projects of nuclear airplanes, with unlimited range of operation, were present since 1960'.
And so, even if nuclear spaceplane would be implemented, it would be a very special thing. It should be operated on some very distant places, and not every country would be able to permit such things to fly over their sky. There would be complications, connected with flying of those spaceplanes over territory of some countries, and maybe, even an ecology activists movement against such a things would arose, making them yet more unconvenient due to legal restrictions.
And more: remember 9/11. What if nuclear spaceplane would become an instrument in hands of terrorists (and let's not forget, most of terrorists are really operated by Moscow KGB nowadays)? Nuclear spaceplane has unlimited range of operation, it is fast and unpredictable, and explosion of its nuclear engine is similar to explosion of small atomic bomb. How do you think they would use it?
Also, even if nuclear engines one day would become good enough to reach needed Isp for SSTO, they still would be very, very expensive. That way, cost of a kilogram on LEO would be high - so what's the use of all the thing, wouldn't it be better to use my 3STO design instead?
Last edited by Yuri Pilipishin (2017-06-19 10:24:50)
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Once you start staging your spaceplane to compensate for the weaker available propulsion, you end up in the same tail-chase of massive launch weight (cost) and low delivered payload fraction (even more cost) that made the US Space Shuttle and the Soviet "Buran" space shuttle unattractive. The US shuttle put a 100 ton spaceplane in orbit to deliver 15 tons of supplies, with a launch weight near 2000 tons. That’s under 1% deliverable payload fraction. It cost about $1-1.5B to launch. That's $60-100M/ton.
Compare that with the kinds of prices in the competitive satellite launch business today, even with expendable rockets. That's around $5-6M/ton in sizes between 5 and 20 tons. That’s an order of magnitude lower than shuttle. It's about to fall to half that value with 50 ton capability soon (there is a slight beneficial effect of larger sizes). Reusability of some parts of the rockets promises to reduce that still further.
There would be a big difference between cost efficiency of Shuttle and the one of the completely reusable spaceplane (even if their deliverable payload fraction would be similar, about 1/100); the matter is, Shuttle was not completely reusable, nothing like refuel-and-immediately-launch-it-again thing. Manufacturing of a big expendable external fuel tank was very expensive, and also, SRB's needed a lot of costly maintenance between launches. And if the maintenance was poor, it lead to disaster (as with Challenger), so quality control was needed, making the whole launch cycle even more expensive. On the contrary, the completely reusable spaceplane would need only refueling for a new launch (and maybe some routine technical checks up, like any other ordinary aircraft); this means, the price of one launch (and price of one kilogram on LEO, either) would be a few orders of magnitude lower.
The other reason why Shuttle was not very effective, is that its universal capabilities were used not completely. The main purpose for such a reusable spaceship, with that large cargo bay, would be not to bring objects to orbit, but to land them back to Earth; in order to just bring some satellite to orbit, such a big reusable spaceship was rather an overkill. This was understood by Soviet designers, when they created the system Energiya - Buran: they "moved" the main engines of the second stage from orbiter to external fuel tank, making this external tank a full-featured second rocket stage. That way, the whole philosophy of the system had been changed: there was not a rocketplane with a big external tank and solid rocket boosters, but instead a full-featured, two-staged rocket (Energiya), with a side-mounted payload; one of the variants of which payload could be reusable winged spaceship (Buran). That way, with similar launch weight, maximal cargo weight on LEO was about 100 ton (for a first time, Energiya was launched without Buran, bringing nearly to orbit a 100 ton "model" of military laser space station).
That way, from one point of view, Energiya-Buran was better than Shuttle; we don't need to bring to the orbit the whole spaceship, if only rocket is enough; and it could bring to the orbit a much heavier cargo, about 100 ton; but when we need to complete some special tasks on orbit, or to land some satellite back to Earth, than we could launch the reusable spaceship. But also, and it was understood, the main subject of prestigious competition was reusability itself; and from this point of view, Energiya-Buran had lost, because it was less reusable: even though that four rocket boosters of the first stage were planned be done reusable, the whole second stage was not. That way, Buran lost to Shuttle the main prestigious prize: its second stage engines were not reusable, and they even not were planned to become that.
I remember how it was unpleasantly to me these days in 1989, to understand that my country lost the prize of prestige in this competition; and I was trying to invent, how the rocket like Energiya could be done completely reusable: if this would be done, we would win all the competitions over Shuttle. There is nothing especially difficult to made boosters of the first stage reusable: the only thing that's needed to implement is soft landing. But to save the big central block, it was needed to implement its safe reentry in atmosphere from space velocity. And that's the design invented by me these days:
The main idea is: because the engines are much heavier than empty fuel tanks, the central block should reentry with its engines forth; that way, we need to add some unfolding lattice fins on the upper part of the block, which becomes rear at reentry; and also to place a heat shield under the engines, so they could survive the reentry phase. When climbing into orbit, the heat shield, in form of disk, is docked on the pylon placed on the side of central block, opposite to the payload, forming a kind of streamlined T-shaped stabilizer. After the payload is released in space, the heat shield disk should be re-docked under the block of engines, on the special heat-protected robust skirt, closing the engines from heating on reentry. Of course, the unfolding lattice fins should also be implemented heat-proof; and some heat protection, probably, would also be needed to cover the whole body of the central block, although it should be much more lightweight, because it should protect only from tangential heating stream (and maybe, it would be even possible to do without heat protection, only heat-proof side parts of central rocket block, e.g. made from heat-proof steel); it should be taken into account, that side parts of central block would be slightly shadowed from that heating stream by flanges of the heat shield disk. In order to stabilize the central block and minimize its random tilts during the hot reentry phase, which would lead to touching of its sides by heating stream of air, the central block could be also made rotating about the longitudinal axis (after the hot reentry phase is over, the rotation should be stopped, of course).
In Soviet project of Energiya, four blocks of its first stage should be landed with parachutes on a ground; but, in my imagination, landing of all blocks of the rocket (four side ones and the central block) would be better done on water: for safely landing on the ground, they seems too large. In order to land the fragile rocket block more gently, it would be possible to use gliding parachutes: first, they could bring the landing rocket block exactly in proper place by gliding, so we could land them not only in the sea, but also in lakes and even rivers; and second, the gliding parachute could, just before touching the water, accomplish a maneuver decreasing the vertical velocity to nearly zero. At that, the rocket block should be hanged under the parachute in a proper orientation: nearly horizontally, with engines forth and slightly up (engines are heavier, so by reaction of air, the block would orientate itself "engines forth"). That way, when touching the water with nearly zero vertical velocity and some horizontal velocity, the rocket block firstly would start sliding on water, gently touching it by its part being opposite to engines. Then, as the horizontal velocity decrease, the rocket block would plunge into water more and more, until the whole velocity would be zeroed. That method of landing rocket blocks on water, under the gliding parachutes, seem to be maximally careful, somewhat resembling landing of a hydroplane with a very big wing.
That way, it became possible to implement complete reusability of the whole rocket. If we need only to launch satellites, this reusable rocket could do it by itself, without spaceship, with maximal possible deliverable payload fraction. For operations on orbit, or to bring satellites back to Earth, we could launch reusable spaceship; and the whole system, of rocket and spaceship, became completely reusable, with no expendable parts.
In order to make the landing of fragile rocket blocks even more careful, it also came to my mind that the rocket blocks, when descending under parachutes, could be catched by helicopters, clinging them to a special loop on top of the parachute, by a long rope with some hook on its end (much later after 2005, I had read in the Net that USSR tried such picking up of returned rocket blocks by helicopters for their reusability; but I didn't knew it then). The problem with this idea was, the blocks of Energiya are very heavy (the empty cenral block would weight nearly 100 ton): there are no such cargo helicopters which could carry that load; and creating of special ultraheavy helicopter seemed too expensive, if even possible.
[On a hint from my team: presently, implementing of such a big 100 ton rocket, like Energiya, would be commercially unfeasible; but, this general design of completely reusable two-staged rocket, with side-mounted cargo, optionally carrying a reusable winged spaceship, is easily scalable. The maximal cargo weight for helicopters that we currently operate is about 25 ton. That way, it seems profitable to implement a completely reusable rocket by that design, with empty weight of central block about 20 - 25 ton; it would end up with its maximal cargo on LEO about 15 - 20 ton. For landing of the returning rocket blocks we could unite the both ideas: when descending under gliding parachute, the rocket block is catched by helicopter, which provides the most careful treatment for reused blocks; but, if helicopter failed to catch some rocket block, then it lands on water, so it would be anyway saved and reused, but maybe with somewhat more maintenance. Also, for that rocket it would be possible to implement a reusable winged spaceship: to maintain satellites in space and bring them back from orbit to Earth, visit space stations, ets. This project seems much better than other existing projects of reusable rockets, because of its mass- and cost efficiency, and much better survivability and reusability of the reused rocket blocks.]
Taking into account, that my internet activity is most probably overheared by hostile parties, interested in plagiarization and stealing of my inventions (probably Russians, which were already caught on attempts of plagiarization of my invntions; but, not excluded, also someone other), I again add this my standard paragraph. My project(s), described in this post (and in the whole thread), are all my intellectual property. All of my intellectual property is prohibited to use without my written permission. In order to prove my authorship and priority on that project(s), as well as on all of my ideas, I would pass a test on a modern variant of lie detector (subliminal questions, answers from the unconscious, but without any possible control or accountability).
Last edited by Yuri Pilipishin (2017-06-19 11:24:29)
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Honestly, I don't see much advantage to pursuing a multi-stage spaceplane. I would see an advantage to pursuing the advanced propulsion needed to make a single-stage spaceplane feasible. I definitely see advantages to pursuing lower cost one-way rockets to orbit, and capsules to come home in. Use them to assemble your deep space craft in orbit, and base those deep space craft out of orbit.
What's the problem with spaceplane if it is not SSTO but 3STO? (All modern space rockets are not SSTO, they are 3STO or, rarely, 2STO: because staging increases mass-to-orbit payload fraction). Probably, the only disadvantage is, one couldn't use the thing as a means of personal global transportation, for intercontinental travel, without bothering to remember "on what airfield I had leaved my first and second stages?" But, this is not the main commercial use of the spaceplane; for maintaining many thousands of satellites of global Internet, 3STO makes no problem, as far as the thing provides the best possible price. For military operations, 3STO makes probably less problem, as compared with nuclear-powered thing: there is no bother with some heroic infantryman being tired of killing Moscow imperialists, falling asleep too nearly to nuclear reactor of spaceship and getting a radiation sickness; and if all three stages landed on different airfields, the first stage could fly by itself, to pick up the second stage, together they could fly to pick up the third stage, and fly back to home airfield (to be precise, an additional cargo aircraft with auxiliary team and equipment is needed, to assembly the stages into one system).
I even could imagine a model of personal use of these spaceships (third stages of my spaceplane) in future, when these spaceplanes would become standard: the first and the second stages would be considered rather as an additional means of airport, which would provide services of not only keeping of the spaceships in hangars, its technical maintenance and refueling, but also the service of launching spaceships into space, using the first and second stages (so the third stages would be operated by customers, when first and second stages would be operated by airports). And moreover, I could even imagine a service of space refueling of these spaceships (third stages of my spaceplane), which would be done by airports and supporting organizations, operating not only first and second stages, but also the third stages which are refueling tankers. That way, a customer of the spaceship could just order some fuel/oxidizer, being delivered on some particular orbit, for refueling.
On the other hand, personal, and even commercial, use of nuclear-powered spaceplanes seems impossible: if this thing crashes, the reactor become radioactive bomb, and so it would be highly unacceptable to permit such a dangerous technology, especially taking into account the risk that it could fall into the hands of terrorists: in fact, it would become something like unofficial nuclear weapons with global reach.
Last edited by Yuri Pilipishin (2017-06-19 10:37:19)
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As I said in a previous post, I doubt there's much in the way of overall staged spaceplane configurations that is patentable, but there's still a bunch of ways-and-means technologies that would be patentable. You won't know until you do the patent search.
Of course, I had done quite a thorough prior art search; and as far as I am informed at the moment, there are no other non-nuclear completely-reusable horizontal-take-off-and-landing spaceplane project which would be comparable. There are a lot of single- or two-staged designs, that are not able to reach orbit, at least at the present level of technology. Also, I had found two, very different, three-staged designs, which would be, theoretically, able to reach orbit - but they are much worse as compared with my project (having smaller mass-to-orbit payload fraction, smaller cargo-to-orbit weight with possible dimensions/weight of the thing, and greater price of a kilogram on LEO).
First, there are a few similar designs, in which a two-staged rocket system, with both reusable winged rocket stages, is carried and started into space from a heavy turbojet cargo aircraft. The third stage, obviously, should be done with heat protection, and also the second stage need to be somewhat heat proof, probably "hot airframe".
This design(s) need(s) a very big carrier aircraft, for the mass-to-orbit payload fraction is very low, probably 1/1000 or slightly more.
Second, there is an old design, with three reusable winged stages, horizontal take off; it's Lockheed System III (1963).
All the three stages use rocket engines, which is uneconomical (it's better to use air breathing engines on altitudes up to 50 - 60 km); also, the third and the second stages would need heat protection; therefore, the mass-to-orbit payload fraction would be small, much less that 1/100, and price would be high.
That way, I have not seen any prior art which would be similar to my project, or which would be better or even comparable; if you know such a project, please present it here, so we could compare them in discussion.
Also, it should be mentioned, unfortunately I have a reason to expect all kinds of attempts and dirty tricks to steal my intellectual property, from Russian FSB(KGB) or maybe some other hostile parties. Achievements of the USSR in space are a very significant part of national mythology of modern KGB-ruled imperialistic Russia; and so, they looks on every our Ukrainian achievement in space with great envy and jealousity. That way, even a project of my spaceplane - with all those capabilities to reach Moon, Mars, asteroids, and with complete reusability - is not only scientifical achievement, but also it becomes a politics, because Moscow's own projects of spaceplanes are much worse. And there are all reasons to expect their countermeasures, in order to steal or compromise my intellectual property rights on that thing, or to obstruct implementation of the project (which by the way could be implemented on our native Ukrainian facilities: Yuzhmash, Antonov, Motor-Sich). At that, KGB-ruled Moscow has a bad habit to operate under false flag, by someone else's hands, using their paid agents on the very top of Western world, enforcing Western governments to betray Ukrainian interests: by bribing the West with big money, or corrupting the West by their agents, or threatening the West by nuclear weapons, and so on. Moscow KGB, oftenly operating by someone else's hands, tries to exclude the threat of implementation of this project; and, may I say, the threat to Moscow is real.
Even an implementation of the very basic variant of my spaceplane, only reaching low Earth orbit, would became a crushing blow into the Moscow national pride - something alike that USA felt when Sputnik was launched. After success of Apollo project, Moscow is somewhat accustomed to lose to Americans - but if they lose to Ukrainians, it would be ideologically devastating to them. But again, this is only beginning.
What if we Ukrainians were not only the first who launched completely reusable spaceplane, but reached the Moon on it? Asteriods? Martian satellites? Mars? With complete reusability? All this would became crushing blows to Moscow national pride; they would feel themselves as historical loosers, the whole public opinion of Russian Federation would feel catastrophically disappointed, and this could lead to overthrowing of their evil KGB-ruled regime.
Again, this is not all. Commercially, the project would be quite profitable, maintaining thousands of satellites of global Internet, and of other telecommunnication facilities, for example TV transceivers on geostationary orbit. But also, with such a cheap prices of transferring satellites on all Earth orbits, it would became possible to create a global space-based anti-missile defense: something like SDI, but on the new level of technology. And this could disarm Moscow not only ideologically, but also from a military point of view. If it became possible to destroy their ICBMs, SLBMs, and strategic bombers on their flight path, Moscow would lose their final argument of nuclear war (which is used by them oftenly, rather to threat: here in Ukraine we know it very well, especially after summer 2014). And all of this could not only overthrow their KGB-ruled regime, but could also, probably, lead to disintegration of the whole Russian Federation (there are already quite a few national autonomies inside RF, seeking for state independence: Tatarstan, Kalmykia, Chechnya, Tuva, even Yakutia...)
First of all, it would be possible to launch the simple, non-nuclear variant of SDI with many satellites, Brilliant Eyes/Brilliant Pebbles; after that, it might be possible to launch nuclear expendable X-ray lasers, Excalibur; this would probably be enough to made Moscow strategic nuclear forces significantly weaker (the capability of my spaceplane to reach not only low, but also all high orbits, with refuelings, would be the key). And here in Ukraine we also have some more inventions and ideas, concerning space-based anti-missile defense, which I will not disclose at the moment.
This is the explanation, why Moscow is using all their possibilities to block, obstruct, and compromise this my project of spaceplane. They understand the threat, and are trying to annihilate the enemy preventively (and I've even heard, how much money they are trying to pay to Western top officials in order to gang up and block this my project together).
Of course, when inventing the thing, I understood that it would be probably not enough to protect such a project by ordinary commercial patent filing; since inventing in 1999, I just kept it completely secret, not telling about it. In 2005, when I thought a team of patriotic pro-Ukrainian individuals came to power, it seemed the time had come. But unfortunately there was a danger of informational leaks; and my inventions, disclosed for some people, were secured by something like a secret patent filings (not by the ordinary commercial patent filings, but by something giving much stronger protection, something like that is preventing, for example, Russian Federation from replicating a shape of American B-2 Stealth bomber: the whole idea is well-known, but replicating is still prohibited). We knew, since than, that Russian intelligence, and other parties, could be informed about these inventions, and there was a struggle to protect my inventions from plagiarizing. That way, I have some reasons to presume, that Russian special services, or other interested parties, were doing some cunning tricks since 2005, not excluded fabricating forgeries, even by their agents in other countries, in order to steal or compromise my inventions - and, of course, I would like that all proper measures should be taken in order to protect all my intellectual property from plagiarizing, stealing, compromising, using without my permission, and so on.
Last edited by Yuri Pilipishin (2017-06-19 10:49:50)
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Yuri:
I see nothing wrong with your 3-stage design. My comments apply to taking wings along where you don't need them, and long-term human life support along when you don't need it. The dead weights those incur are disastrous.
I think you might have an over-enthusiastic idea how wings on a spaceplane might help with aerobraking at a destination with an atmosphere like Mars. If your "fuselage" has a belly heat shield, it can do the aerobraking without the wings, and with a less sophisticated heat shield. Wings are at risk of breaking off if your vehicle assumes too broadside an attitude. Being more nose-into-the-wind creates nosetip and leading edge overheat problems you don't have dead broadside. Plus you save considerable weight with no wings.
That's why most of us think spaceplanes are for surface-to-orbit and back at Earth. You use something else for the interplanetary destinations, something more optimised for that job.
A lot of us also think that the ratio of deliverable payload to gross takeoff weight is inherently smaller than with vertical launch rockets, whether expendable or not. A simple payload shroud is, and always will be, lighter than a winged vehicle capable of entry. So, one-way delivery of cargo to orbit will be more cost-effective with vertical launch rockets. The only question is how much further stage reusability can depress launch prices.
Point is: all these things have their proper application. Trying to use one where it doesn't fit as well is a recipe for unnecessary expense, even if it actually does work.
GW
Last edited by GW Johnson (2017-06-20 09:21:53)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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