A cheap and easy way to space.

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halman

Guest
scottb50,

You are correct, the White Knight II does used four engines.

The Solid Rocket Boosters are jettisoned at about 150,000 feet, not 250,000.

In my concept, the fully fueled orbiter would weigh about 500,000 pounds. Take off weight of the stack would be around 1.3 million pounds. Maximum take off weight of the C-5 is 840,000 pounds. We should be able to do better than that.
 
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halman

Guest
Basically, what I am proposing to do is to lift the launch pad to about 50,000 feet. By doing so, whatever we launch is going to be able to use all of its fuel for accelerating, without wasting half of it just fighting gravity. This is what makes our launch vehicles today so large in comparison to the payloads they can lift to orbit, having to fight gravity until they can reach an altitude where the air density is low enough that they can begin to accelerate with the full power of their engines.

The carrier wing has nothing to do with accelerating the spacecraft, it just lifts it through the densest part of the atmosphere, by using that atmosphere for lift and to provide oxidizer for its engines. The catapult is simply a way to accelerate the carrier wing and its payload to takeoff velocity quickly, and without having to use a lot of the fuel of the carrier wing.

Another goal of this launch system is to make it possible to launch in conditions which are less than perfect, and without having large numbers of people monitoring every aspect of the launch vehicle, each with the ability to postpone or cancel a launch. Think of an airliner departing on a journey, which will occur in practically any conditions. This is the kind of utility we need in a space access system.

Instead of using the most advanced technology available, the highest performance fuels, the most radical designs, this system would be as simple, robust, and reliable as we can make it. After we get our costs per mass unit to orbit down, we can begin experimenting with different engines, nozzle types, and so on. But we already know how to build rocket engines which burn kerosene and liquid oxygen efficiently, while providing lots of thrust. We have learned how to build turbo pumps which will supply those engines with enough fuel for continuous operation, cooling strategies which will prevent those engines from melting, and so on down the list.

There is nothing new in this proposal, except for launching from the back of an aircraft, which I am confident we could master. The wing will be larger than any that we have ever built, but there are no fundamental limits to the size of a wing. It just means more power to overcome the drag.

Until we have a system which can provide access to orbit on a regular basis, cheaply, reliably, and safely, progress in space exploration is going to be limited, and large scale investment by the private sector is going to be scarce. It is that investment by the private sector which is the key to our future, because only that will insure that we will continue to expand our sphere of activities beyond this planet.
 
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scottb50

Guest
halman said:
Basically, what I am proposing to do is to lift the launch pad to about 50,000 feet.

What I propose is lifting well above 50,000 feet. Say 30 miles and Mach 5, near Shuttle numbers, Fly back booster with independent upper stages. Upper stages generally go to LEO, but configuration can vary significantly.

I say launch it, fly it back, re-fuel it and launch again. Basic Shuttle technology and configuration at much lower costs.

I think it gets significantly more payload into LEO, and from there to wherever. Shuttle, or Delta engines to begin with and upgrade to bigger engines as they get better. Centaur based upper stages in various configurations, with future upgrades as well.

Basic Shuttle facilities and launch equipment to begin with.
 
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vulture4

Guest
scottb50":2s7tajfl said:
halman":2s7tajfl said:
Basically, what I am proposing to do is to lift the launch pad to about 50,000 feet.

There was at one time talk of launching the X-34 from a carrier aircraft, and then launching a small upper stage from the X-34. Even in that situation, however, the X-34 "second stage" would have o land a few hundred miles downrange from the point where it separates from the carrier aircraft.
 
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Sumontro

Guest
Instead of a two stage system, why not a single stage to orbit spaceplane? It could use turboramjets for thrust at lower altitudes, and rocket engines to boost to orbital speeds. The whole thing would essentially be an aircraft that can go into space. The larger wing required to carry the fuel necessary to get to orbital speeds would serve a dual purpose of reducing heat loads during re-entry. We have all the technology needed to make this happen NOW, and the scaled composites and SpaceX are proving how the development can be done cheap enough to allow venture capital to fund it.
 
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frodo1008

Guest
Halman, the US military Black Budget (which is many times greater than NASA's entire budget) already has in full development fighter types of aircraft that can reach the lower regions of hypersonic flight! I would say in the area of 4 to 5 mach at least. I do not have to be actually involved nor be giving away any military secrets to know this, just have some knowledge of how the military mind works, and use a little logic!

I have every confidence that with the 10's of $billions of dollars available, and the desire of the US military to be able to respond to trouble anywhere on the Earth in a few hours at most, that the military IS going to solve the basic problem of having a piloted plane take off from an airfield (or even the deck of an aircraft carrier) using normal jet engines and then get up to the lower region of hypersonic flight, and then switch over to scramjet engines. Then such an aircraft would be fully capable of accelerating up to the higher hypersonic region of 10 to 15 mach. And then show up anywhere on this Earth in less than two hours!

The US military is the ONLY organization with either the desire or certainly the funding to overcome the problems of such a system, but I would not be at all surprised to see them achieve such a level in less than a decade. Of course, we all know that in the beginning (just as the stealth technology was, and to some extent still is) that this technology will be indeed highly secret. But we also know that every development of the military similar to this since WWII has eventually gotten into the civilian sector. And while civilian aircraft do not really need stealth technology (in fact, in most cases civilian aircraft want to be seen by radar!), The ability to travel in the hypersonic region will be a great key for civilian aerospace developments!

Once such aircraft can get up to such velocities, and at altitudes of 100,000+ feet, then it becomes relatively easy to place small aerospike rocket engines on such vehicles (remember linear aerospike engines can take the shape of just about any kind of rear end of any flying vehicle). Ignite such a rocket and get the extra 10 mach to 25 mach or orbital velocity then becomes relatively simple.

It would not require a very powerful rocket, or very much fuel to achieve orbit once the problems of achieving higher velocity hypersonic scramjets is accomplished.

Then it becomes just a problem of scaling up such vehicles to carry more weight in either people or materials or both to accomplish the "Holy Grail" of machines capable of flying from the earth's surface literally into LEO!

NASA could never accomplish this, as NASA's funding is insufficient to develop such technology, and at the same time continue with all of the other things that so many people want NASA to do. But the military (and especially the Black Area programs) do not have such restrictions.

Remember it was not NASA that developed the EELV program that resulted in the Delta IV and Atlas V rockets, it was the Air Force (and that program was not even that secret, nor even a Black program). This EELV Air Force program was not meant to revolutionize the launching of rockets, just bring down the very high (over $10,000 per pound to LEO) cost of the Titan IV Heavy series of rockets that the military had to depend on to launch heavy spy satellites to GEO orbit.

What the Air Force did in that program was to have both Boeing and LM develop large rockets whose major goal was to reduce by as much as current levels of technology would allow, the costs of placing satellites into orbit. And the program succeeded admirably as the cost to the military and other governmental agencies for such launches has been reduced to less than $5,000 per pound to LEO. And if the satellite launch market had remained robust enough, the methodologies developed by Boeing/LM for the assembly line construction of those rockets would have brought down the costs to less than $2,000 per pound to LEO. But unfortunately that did not happen at that time, nor certainly not now with the world's economy being what it has become.

But, I fully believe that eventually this reduction will actually happen, and with spacex possibly joining in, the price of placing a pound of materials into LEO with large conventional rocket boosters I fully believe will come down to the somewhat magic amount of lower than $1,000 per pound to LEO, thus opening up far more business into space itself!

And I also believe that the military will once again come to the rescue by developing the true NASP type of craft, that eventually will bring the price of placing both people and materials down to even far lower levels.

IN the meantime NASA needs to keep up the imaginations and hopes of ordinary people by getting us back to the moon, and then going on to Mars. That is NASA's true calling, it is to be at the cutting edge of taking us outward bound ahead of all others (with the possible exceptions of the excellent space programs of other countries throughout the world), and allowing both the military and eventually pure private for profit interests to eventually follow up to give humanity a true space faring civilization!

So there is really a whole lot more hope than I sometimes see exhibited here on these boards! :D
 
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Sumontro

Guest
Actually, there is a HUGE potential market NOW for the industrial usage of space. Already, biotechnology and pharmaceutical companies are beginning to look to doing research in orbit. Also, the semiconductor industry could HUGELY benefit by shifting manufacturing into the clean vacuum of orbit, solving their yield and cost problems in one blow. This, totalled with the pharmaceutical, biotech, and the existing telecommunications market constitutes a total market of 1.7 trillion dollars. <self promotion removed> elaborates more on why these industries would shift their operations. This more than justifies the development of a reusable, reliable, SSTO spaceplane. Also, Scaled Composites clearly proved that a development program can be done on the cheap, so the capital requirements could be in range of private venture capital, or mixed private public funds.
 
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Dagonet

Guest
I think that it is important to note that all of us desire a cheap and easy way to access space, whether for personal or commercial benefits. Personally, it doesn't matter the motivation, most of us realize the potential for what this step in humanities evolution means. What is most important is unity on a single issue, the future of mankind. Our lifetimes may never see the kind of adventure we seek, but imagine what is possible for our children, our grandchildren! Of utmost importance is in seeing what we dream of being obtained by those we hold most dear. A way to conquer space, as we have conquered planet Earth. The next great adventure for mankind. What else do we have to do except feud among ourselves? Some of us may desire to traverse the stars by developing complex designs, propelling us into the future, and some of us may desire to incorporate designs of our fathers, propelling us to the moon. Our common goal is the same, to develop the future of mankind, and prepare us for the world of tomorrow. I pledge to do all that I and my family can, to advance the human race towards this common goal that we share. Unfortunately, I can only do so much, appearing on an online forum. I urge those who have companies seeking the expansion of the human race to the stars to come forward and ask for our help, and those who have experience to offer it. We can all do so much more together. I believe that the ideas mentioned in this thread are instrumental to developing this future. Is there currently any individual forum or place that empathizes these ideals? If not I propose the creation of this forum or site where these ideas can be maintained or spread.
 
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halman

Guest
Welcome, Dagonet!

This site is full of threads devoted to the commercial uses of space, which are abundant. There is no doubt whatsoever that economic development off-planet would accelerate rapidly if we had a cheap and easy way into space. In spite of considerable talk, the private sector is not moving very quickly to address this lack, and the government programs are aimed at exploration beyond Low Earth Orbit.

As appealing as the Single Stage To Orbit concept is, the amount of energy which must be imparted to every atom of payload is simply staggering. 5 miles per second is beyond our experience, impossible in an atmosphere. Yet, we have to pour that velocity into whatever we want to put into orbit. Taking the whole launch vehicle to orbit is simply beyond our capability at this time, in terms of any useful spacecraft.

I am convinced that only by narrowing the job description of the spacecraft, and minimizing its abilities, can we create a viable launch system that is reasonably priced to operate. Frodo speaks of the military getting the price to orbit below 5,000 dollars a pound. That means it would still cost over 80,000 dollars for me to travel the 120 miles into space. We need a system that can reliably transfer people, and only people, into orbit for 500 dollars a pound. And we need it yesterday.

Someday, I have no doubt that there will be vehicles which can take off from a regular runway and reach orbital velocity. But trying to build them today will set back the revolution that is waiting to happen on the other side of the sky. And that revolution holds more promise than the New World did for Europe 500 years ago. Investment that will produce real wealth, not bubbles.

I am certain that everything I have proposed is feasible, right now, with existing technology. No breakthroughs are needed, no development of new materials is required, the ground work has already been done. What is needed is the willingness to embrace different ways of doing things, the wherewithal to complete what is started, and a few billion dollars. In exchange, we would have a workable transportation system, capable of supporting the expansion of our presence off-planet for years to come.

Once we have firmly established ourselves out there, then the money for improvements, new engines, and materials made in space will become available, and, eventually, we will have singe stage to orbit. But right now, we need to advance past launching rockets straight up to get into space. That is fine for big payloads, but it is just too expensive when it comes to rotating crews. And people on the spot will be essential for this revolution to happen. We are not going to do it with robots and remote control, but with people. Engineers, chemists, physicists, technicians, and people whose job it will be to keep all of them alive.

Launching a rocket to send 5 or 6 people up is not the solution. Sending up 10 at a time, with flights that are scheduled, day in, day out, that is the solution.
 
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scottb50

Guest
Once we have firmly established ourselves out there, then the money for improvements, new engines, and materials made in space will become available, and, eventually, we will have singe stage to orbit. But right now, we need to advance past launching rockets straight up to get into space. That is fine for big payloads, but it is just too expensive when it comes to rotating crews. And people on the spot will be essential for this revolution to happen. We are not going to do it with robots and remote control, but with people. Engineers, chemists, physicists, technicians, and people whose job it will be to keep all of them alive.

Launching a rocket to send 5 or 6 people up is not the solution. Sending up 10 at a time, with flights that are scheduled, day in, day out, that is the solution.....

Day in Day out can't be an immediate goal but we have the science and engineering knowledge of how well the Shuttle has done to more than prove the ability to do it. It's now time to exploit that knowledge and run with it.

Large payloads are critical, though having two, or more, smaller size launchers available would make more sense, as long as their use is interchangable. Vertical launch is a given. Shuttle ground equipment and launch facilities could be used for the initial operation. Obviously newer things will be needed, but that would get things going. Better then selling it for scrap.

Key would be using Common Cores, identical Modules used in different ways. A Heavy lifter would use five Common Cores, three liquid and two solid, a two liquid, two solid version would also be used for one way launches. Upper Stages would have liquid Common Cores and a payload.

As you say getting people to orbit is primary, an independant Upper Stage that can leave the First Stage on the pad or anywhere on the way to separation, powered landings normally and in case of failure.
 
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halman

Guest
Putting 10 people plus a crew of two into Low Earth Orbit in a module capable of separating from the first stage on the pad and lifting to safety will mean using a heavy lift launch vehicle just to get people into orbit. And we still are dealing with a large work force involved in each launch, plus ideal conditions.

A real heavy lift launcher is essential, but we should avoid man-rating it. The added complexity and expense is unnecessary, I believe. But we need something that can launch an Orbital Transfer Vehicle, so that we can send our payloads to the lowest possible orbit. The crew would be launched separately, and would reside in a station. They would be rotated out on a regular basis.

Breaking down the climb to final orbit into steps that are performed by vehicles specialized for each regime is the secret to cutting costs, I believe. Instead of building a rocket that will put X amount of pounds in geosynchronous orbit, we should put that payload into LEO, and then move it to the desired orbit with a vehicle designed specifically for space operations. Otherwise, we are being inefficient, by having to send the fuel and the engines which will be used in a zero-gravity, airless environment up from the Earth's surface, and then throwing the engines away.

What is holding up the next industrial revolution is not lack of knowledge, because we already know many products and processes which will be profitable in the long term. It is access to space, getting past the atmosphere, and accelerating to orbital velocity. We can drastically reduce the costs of sending mass into space by building simple, expendable, rockets and flying them frequently. But man-rating those rockets makes them complex and expensive.
 
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bushwhacker

Guest
Having gone thru all 4 pages of this thread. I have to say Halman has made some very good points.
I'm not a rocket scientist or any other for that matter. but i do look at things logically and this proposal just makes sense
 
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halman

Guest
Thank you, bushwhacker!

I wish that I could take the credit for thinking this stuff up, but I am only expressing what the original goal of the shuttle program was, and the means that the NASA scientists had developed to achieve them. My only contribution, and I can not even say for sure that it is original, is the electromagnetic catapult. But it seems a natural extension of the principle of utilizing the available resources to the greatest possible level. Plus, it takes care of the problem of supporting a couple of million pounds of vehicles without adding to the weight of the vehicles. By using the catapult, the take off roll is shortened considerably, and the engine requirements are minimized.

So, it is a great idea. But it is just an idea, which may never come to pass, unless someone can figure out a way to pay for it. What really bums me out is that there is plenty of money in the world looking for projects to invest in. The world equity markets total something like 6 trillion dollars! (Those are stock markets.) The Chinese could pay for this whole thing without even blinking. The entire program would almost certainly cost less than the Defense appropriations for one year. I am confident that the development and construction of the various elements of this system would cost less than 200 billion, and probably more like 80 billion.

But, as long as we are mired in national ego trips, defense posturing, and all the other things that prevent international co-operation, this system will never fly. The United States is intent on building a rocket which duplicates not only the abilities of Russian and Chinese rockets, but even our own private sector launch vehicles. To what purpose? Merely to insure that the U.S. has its own spaceflight capability? What good will that do us if we cannot afford to go anywhere?

The whole planet needs this launch system that I am advocating, because the whole planet will benefit from the industrial revolution in space. Not only economically, but, eventually, environmentally, I believe. We won't need to worry about greenhouse gas emissions when we are in orbit, because they will not affect the Earth. We don't need to worry about pollution when we are in orbit, because it will not affect the Earth. (And it is pretty hard to pollute space.)

Putting good sized payloads in Low Earth Orbit is not the problem, we can do that easily, with existing hardware. Putting people in orbit is the problem, because we have no cheap, reliable, safe way of doing that, and this revolution is not going to happen unless we can transport people to orbit and back in sizable numbers.
 
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DarkenedOne

Guest
halman":3l2dz5te said:
Putting 10 people plus a crew of two into Low Earth Orbit in a module capable of separating from the first stage on the pad and lifting to safety will mean using a heavy lift launch vehicle just to get people into orbit. And we still are dealing with a large work force involved in each launch, plus ideal conditions.

A real heavy lift launcher is essential, but we should avoid man-rating it. The added complexity and expense is unnecessary, I believe. But we need something that can launch an Orbital Transfer Vehicle, so that we can send our payloads to the lowest possible orbit. The crew would be launched separately, and would reside in a station. They would be rotated out on a regular basis.

Breaking down the climb to final orbit into steps that are performed by vehicles specialized for each regime is the secret to cutting costs, I believe. Instead of building a rocket that will put X amount of pounds in geosynchronous orbit, we should put that payload into LEO, and then move it to the desired orbit with a vehicle designed specifically for space operations. Otherwise, we are being inefficient, by having to send the fuel and the engines which will be used in a zero-gravity, airless environment up from the Earth's surface, and then throwing the engines away.

The problem with specialization is that you decrease the market size for your rocket. The more you specialize the less customers you have. Now this fact would be ok if there were still enough customers to sustain your rocket, but that is not the case in today's launch market. The launch market is dominated largely by fixed costs. These costs include the cost for employees, the costs for launch pads, the cost of factories, the cost of development, and etc. Thus a cost cutting strategy is to increase your launch rate thus lowering your incremental launch cost. The problem that many rocket launchers are experiencing is that there is a current market oversupply as in there is more production than demand. Companies like Boeing with their Delta IV rocket have twice the capacity than they have demand thus driving the cost per launch up higher than it should been.

That was also the shuttle's problem. Nasa expected that the shuttle would fly in excess of 10 times per year in order to justify the large fixed cost it had with all the infrastructure and man power needed to sustain it. When the first shuttle blew up it proved that it was simply not reliable enough to achieve such launch rates. The incremental cost of each launch is only about $80 million as I understand it, but when you factor in all the fixed costs it becomes $300 million or more.

The current launch market favors rockets that generalize and are very versatile like the Soyuz rocket and Falcon 9. Since the Soyuz rocket was built for both manned and unmanned payloads it is able to serve a greater market than the rockets like the space shuttle and the EELV that specialize in one or the other. As a result the Soyuz launch rate is significantly higher than the EELV and far higher than the shuttle.
 
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scottb50

Guest
The current launch market favors rockets that generalize and are very versatile like the Soyuz rocket and Falcon 9. Since the Soyuz rocket was built for both manned and unmanned payloads it is able to serve a greater market than the rockets like the space shuttle and the EELV that specialize in one or the other. As a result the Soyuz launch rate is significantly higher than the EELV and far higher than the shuttle.......

I agree versatility as well as economy of operation are the key factors. While Halman's ideas offer positives the infrastructure required greatly affect the economics. That's why I advocate a Shuttle based follow on vehicle, or vehicles, that take advantage of existing equipment and facilities while simplifying the Shuttle system to reduce manpower and increase safety.

One area addressed is safety, a serious problem with Shuttle that makes it wholly unsuitable for commercial uses. Basically the configuration is similar to Shuttle with a couple of significant differences; The First Stage has fixed propulsion modules, both liquid and solid, housed in an aerodynamic shell allowing flyback, refueling and relaunch. The Upper Stage attaches externally to the First Stage and can ignite and depart from the First Stage at any point from sitting on the launch pad to separation. Payloads attached to the Upper Stage vary from cargo containers and individual satellites to manned return vehicles.

The real secret is identical Modules throughout the vehicle. First Stage liquid and solid motors as well as the Upper Stage use identical Modules, propellant tanks with attached engines and hollow solid motor housings with single piece slide in propellant packs and attached nozzles. The Upper Stage uses the same Modules with attached engines. Each Module is made up of two basic structures multiple Rings and composite wound Tubes, Rings are identical but vary in size depending on their use. As an example a basic Modules consists of two identical Segments attached to one another over a Tube, two identical Rings at each end and four smaller, but identical, Rings around the center. The total number of Segments determine the Modules length. A typical cargo Module would use two Segments, First Stage liquid and Solid Modules would use four or five Segments. All would have single piece Tubes.

The utility of the Modules defines the system, each Ring can dock to any other identical diameter Ring so Modules can attach to each other end to end or side by side. Once in orbit Upper Stages, as well as Cargo Containers can be used to build or add on to Stations and Vehicles. Such a system would reduce costs dramatically and allow large, manned Stations that could replace the individual satellites used today as well as provide components for assembling inter-Planet or object missions.
 
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halman

Guest
DarkenedOne":27rtdrko said:
The problem with specialization is that you decrease the market size for your rocket. The more you specialize the less customers you have. Now this fact would be ok if there were still enough customers to sustain your rocket, but that is not the case in today's launch market. The launch market is dominated largely by fixed costs. These costs include the cost for employees, the costs for launch pads, the cost of factories, the cost of development, and etc. Thus a cost cutting strategy is to increase your launch rate thus lowering your incremental launch cost. The problem that many rocket launchers are experiencing is that there is a current market oversupply as in there is more production than demand. Companies like Boeing with their Delta IV rocket have twice the capacity than they have demand thus driving the cost per launch up higher than it should been.

(What? Over capacity should drive costs DOWN, not up. What I think you might be trying to get at is that the rate of launches has not increased, which means that development costs, overhead, etc., are not being spread out over a large number of launches. Until there is a building boom for space stations, that trend is not likely to turn around.)

DarkenedOne":27rtdrko said:
That was also the shuttle's problem. Nasa expected that the shuttle would fly in excess of 10 times per year in order to justify the large fixed cost it had with all the infrastructure and man power needed to sustain it. When the first shuttle blew up it proved that it was simply not reliable enough to achieve such launch rates. The incremental cost of each launch is only about $80 million as I understand it, but when you factor in all the fixed costs it becomes $300 million or more.

(Economy of scale was critical in the design of Space Transportation System. A minimum of 7 orbiters had to be built in order to keep the 'Standing Army' of technicians working full time to service them, and at least 10 flights a year were needed to utilize the infrastructure often enough to spread the cost out. If the government had been willing to spend the money, and carry through with an orbital development program, STS would probably have been as inexpensive as it was projected to be.)

DarkenedOne":27rtdrko said:
The current launch market favors rockets that generalize and are very versatile like the Soyuz rocket and Falcon 9. Since the Soyuz rocket was built for both manned and unmanned payloads it is able to serve a greater market than the rockets like the space shuttle and the EELV that specialize in one or the other. As a result the Soyuz launch rate is significantly higher than the EELV and far higher than the shuttle.

The only reason that the Soyuz is enjoying such a high flight rate is the Russians are selling launches dirt cheap, in part because the development costs of the launch vehicle were largely written off 20 years ago. The EELV could be flying every day all year, if there were people willing to pay for it to fly. But it is an expensive ride, because development costs are still being absorbed. And I am not going to discuss the Falcon 9 until it has flown successfully a few times.

What I am asking is that people think of launch vehicles in two separate classes; One, which contains all the mass lifters, and the other, which is strictly for carrying people. We will eventually reach the point of loading multiple payloads onto very large rockets, which will carry those payloads to Low Earth Orbit, where they will be transferred to higher orbits by a space craft which is designed to operate only in space. In the meantime, we will see launches of many different sized payloads to orbits and destinations across the board. This is the market for Evolved Expendable Launch Vehicles, the Proton, the Arianne 5, etc.

But we need the capability of putting people in orbit, as well, and this is where we are screwing up. Setting aside the two management-related losses of the shuttle, it has been the one of the most reliable launch vehicles that anyone has ever flown. Yes, that is correct. The Challenger was lost because someone with a great deal of power insisted that it fly that day. NASA didn't want to, but was over ruled. (Think about that: Who has the power to over rule NASA regarding flight decisions? Such people do exist.) Columbia was lost because management refused to acknowledge what the engineers in the field were saying. It was totally preventable, and did not reflect design flaws of the vehicle per se, but problems with the insulation on the external tank.

And the shuttle is the only vehicle which has ever flown which can carry more than three people into space at a time. From what I understand, the Ares, at least initially, will only carry 4, or, perhaps, 5. How many could the shuttle carry if the payload bay had a personnel module in it? 20? 30? More? We can launch space station segments with ease, but putting the people who will use them up there is our biggest challenge. And we need to be sending scientists, not pilots who have some scientific background. The people conducting the experiments need to be up there, not sitting on the ground, telling someone else what to do.

What I am advocating is the creation of a vehicle which will be a bus, carrying people back and forth to space. This bus is going to need to run pretty often once things really start happening, and it has got to be as cheap as possible to operate. Its market share will only get larger, as more and more is invested in materials processing in orbit, then mining on the Moon, then the exploration of Mars and other bodies. It needs to land on a runway, in rain, crosswinds, or fog, and be capable of being turned around in a matter of weeks. It needs to be able to be launched in inclement weather, and it should be designed to permit it to fly back to its base if there is a problem during the launch. It needs to be completely reusable, and operating it should not take more than a dozen people.

It may cost a great deal to get this system operational, but no other launch system is likely to be more efficient, safer, or more reliable at putting people into space.
 
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halman

Guest
scottb50,

The only real infrastructure my proposal requires is the launch catapult and the retrieval runways. And the launch catapult can employ a variety of propulsive means besides just electromagnetics. In fact, something would have to be used to get the stack moving fast enough for the magnetic launcher to be efficient. It could start out with winches hauling in cable, just to overcome the initial inertia, then, perhaps, a rocket sled, which pushes the stack up to 80 or 90 miles per hour, but which is not attached to the cradle, so it will slow down as soon as the rockets are exhausted.

I realize that a magnetic launcher is capable of accelerating a load from a standing start, but the fields generated might not be safe for humans, and could have detrimental effects on the vehicles. But those problems largely disappear once the stack is moving fairly quickly.

All of this is to compensate for the fact that turbofan engines are extremely inefficient at low speeds, especially at low altitudes. But the launch facility will probably be close to sea level, to offer the carrier wing the highest density air to take off with. Using an external power source to accelerate the stack to take off velocity reduces the amount of fuel the carrier wing must carry, while eliminating the need for several miles of runway capable of handling a couple of million pounds.

The space shuttle was the result of huge compromises, which is part of the reason that it has been so expensive to operate. And it was designed to utilize hardware and infrastructure left over from Apollo, such as the Vehicle Assembly Building, the crawler, and all the command and control systems. Personally, I would like to see the shuttle continue operations for another decade, at least, so that we have the capability of putting several people in orbit with one launch. The only reason we won't is because space development is not considered important enough to fund with more than a few billion dollars.
 
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scottb50

Guest
Personally, I would like to see the shuttle continue operations for another decade, at least, so that we have the capability of putting several people in orbit with one launch. The only reason we won't is because space development is not considered important enough to fund with more than a few billion dollars.

Which is my point. The Shuttle, as it stands is not suited to commercial purposes because it has glaring areas where there is little, if any escape. That the basic design is flawed is another matter, problem areas have been fixed or procedures have been developed to deal with them and doing refinement to known problem areas, with a newer, more capable and flexible vehicles only makes sense.

Zero to orbit escape and recovery for manned flights being the first priority. Various upper stage configurations being the next issue. That it can still take advantage of Shuttle processing facilities would be a plus, how long of an acceleration track are you looking at, might be somewhat cheaper in the deserts but higher inclinations become a problem of overflight of populated areas.

I'm thinking quickest to get running, Falcon 9 will do for a few years, but will need a followup and somehow Falcon 15 just doesn't look promising. I think we need a flexible TSTO family of vehicles: Two First Stages, on with two Liquid and two Solid motor Modules and another with four Liquid and two Solid Motor Modules. Upper Stages would use one or two engines and one or two tanks as needed.

The biggest advantage is the Modules, used to build the propellant tanks, can be refurbished for on orbit, or other uses and engines can be used in orbit by Tugs or to propel ships and,eventually, returned for overhaul and re-use.

I don't want to reinvent the wheel, I want to use the SSME and RL-10 engine technology and, hopefully, expand their capabilities or encourage follow on designs. I'm also leaning more to a hybrid Solid design.The Solid housing are fixed to the First Stage and propellant segments are inserted as a unit, separate tanks, for a rubber oxidize, or an aerated wax could also work, though that would be even harder to control.

80-90 mph doesn't make a difference, you would need miles, Spaceship II releases at .08, or so, to launch off a ramp and even get to 50,000ft at .08 would be an undertaking, then you have to get to M25.

All of this is to compensate for the fact that turbofan engines are extremely inefficient at low speeds, especially at low altitudes...

Obviously they are, but can't they contribute in the launch, carry their own weight? In everything I have said they do. The First Stage obviously needs to return and a manned return vehicle needs turbofan engine for landing. That they might produce enough thrust to lift their own and their fuels weight is more then enough reason for their use for launch.
 
W

wskinny

Guest
My proposal is simple, think of the already existing and running maglev train. Now, build a rail track, initially flat on the ground but on the final kilometers stepping up to let's say 45º or 60º. Let's assume a length of about 1000km to allow for a low G force acceleration during the process and accelerate to the needed speed to achieve an LEO, taking in account that we'll be out of propulsion as soon as we leave the tracks, meaning we'd have to accelerate to a higher speed that current propulsion systems to compensate for the speed loss after leaving the launch rail, something that isn't that hard to achieve with an increasingly high power/high frequency rotating magnetic fields.
Now, take in account that we need no rocket to put our ship into space, and the only fuel we need to carry is the one needed to propel our ship during it's mission, that alone will be a major cost reduction. Now account for the expense you wouldn't have to spend now on fuel and rocket construction. Think of the weight reduction of the total mass to be thrown into space. Finally, realize that you would be able to send spaceship after spaceship with intervals of hours instead of weeks or months, largely increasing the return pay for your investment.
Wouldn't this be a much more economically viable launching technology after the initial investment? Wouldn't it drastically reduce the cost of manufacture and launch making it affordable to endeavor in much larger and longer missions?

With such a technology in place a multi-stage comprised Mars/Moon/Asteroid belt mission would be feasible at an incredible lower cost, and maintaining bases on the moon, space or elsewhere would have a dramatic cost reduction.
For the currently proposed future Moon expedition you could in a matter of hours, not days, have the equipment needed for the journey in orbit waiting for an assembly team. (probably more than is currently planned and have immediate capability of setting a moon base on the first journey) The same would apply for a mars mission or any other you can think of.
Even the maintenance and support of any space mission would be greatly improved, finally allowing emergency launches to act on eventual problems or "disasters" that may and will occur in it's time, giving us the means to solve with much more responsiveness and efficiency situations like the Apollo 13 event.
And finally, what would make me a lot happier, was the ability to have a gracious Shuttle like craft, with improved cargo capabilities and with support for much more astronauts on-board at a fraction of the cost of the original shuttle. You could even have cargo specific shuttles and crew only shuttles employing a design like Boing uses on it's planes witch allow for the redesign of the interior according to the costumer specifications.

I honestly believe that a Maglev based launcher technology would push the space exploration endeavor forward tenfold, opening a lot new possibilities in space colonization projects in a very near future with a fraction of the cost of previous endeavors with the same objectives.

Of course we'd still need rocket technology, but after this it would only be needed in space, and all the fuel the rocket would carry would be available for interplanetary missions, making current rockets most likely suitable for missions to mars and maybe even the asteroid belt... Not to mention that we'd be able gain much more speed having all the fuel we needed to leave earth gravity pull readily available for the interplanetary mission, effectively shortening the time needed for such missions...

Furthermore, the ship and launch facilities are totally reusable with minor maintenance...
Am I not seeing something here?
 
C

Chatboy91

Guest
wskinny":1ks2zy8y said:
My proposal is simple, think of the already existing and running maglev train. Now, build a rail track, initially flat on the ground but on the final kilometers stepping up to let's say 45º or 60º. Let's assume a length of about 1000km to allow for a low G force acceleration during the process and accelerate to the needed speed to achieve an LEO, taking in account that we'll be out of propulsion as soon as we leave the tracks, meaning we'd have to accelerate to a higher speed that current propulsion systems to compensate for the speed loss after leaving the launch rail, something that isn't that hard to achieve with an increasingly high power/high frequency rotating magnetic fields.
Now, take in account that we need no rocket to put our ship into space, and the only fuel we need to carry is the one needed to propel our ship during it's mission, that alone will be a major cost reduction. Now account for the expense you wouldn't have to spend now on fuel and rocket construction. Think of the weight reduction of the total mass to be thrown into space. Finally, realize that you would be able to send spaceship after spaceship with intervals of hours instead of weeks or months, largely increasing the return pay for your investment.
Wouldn't this be a much more economically viable launching technology after the initial investment? Wouldn't it drastically reduce the cost of manufacture and launch making it affordable to endeavor in much larger and longer missions?

With such a technology in place a multi-stage comprised Mars/Moon/Asteroid belt mission would be feasible at an incredible lower cost, and maintaining bases on the moon, space or elsewhere would have a dramatic cost reduction.
For the currently proposed future Moon expedition you could in a matter of hours, not days, have the equipment needed for the journey in orbit waiting for an assembly team. (probably more than is currently planned and have immediate capability of setting a moon base on the first journey) The same would apply for a mars mission or any other you can think of.
Even the maintenance and support of any space mission would be greatly improved, finally allowing emergency launches to act on eventual problems or "disasters" that may and will occur in it's time, giving us the means to solve with much more responsiveness and efficiency situations like the Apollo 13 event.
And finally, what would make me a lot happier, was the ability to have a gracious Shuttle like craft, with improved cargo capabilities and with support for much more astronauts on-board at a fraction of the cost of the original shuttle. You could even have cargo specific shuttles and crew only shuttles employing a design like Boing uses on it's planes witch allow for the redesign of the interior according to the costumer specifications.

I honestly believe that a Maglev based launcher technology would push the space exploration endeavor forward tenfold, opening a lot new possibilities in space colonization projects in a very near future with a fraction of the cost of previous endeavors with the same objectives.

Of course we'd still need rocket technology, but after this it would only be needed in space, and all the fuel the rocket would carry would be available for interplanetary missions, making current rockets most likely suitable for missions to mars and maybe even the asteroid belt... Not to mention that we'd be able gain much more speed having all the fuel we needed to leave earth gravity pull readily available for the interplanetary mission, effectively shortening the time needed for such missions...

Furthermore, the ship and launch facilities are totally reusable with minor maintenance...
Am I not seeing something here?

This was mentioned on the first page of the thread. It's only been done on the small scale so far, and once you get to a larger scale it gets increasingly difficult. If I'm not mistaken the issue with this, is that as you increase the payload or size of the craft, it gets much more difficult for the system to accelerate, and less stable, as maglev systems have very little dampening. That, and as weigh increases, you require even more energy and cooling. Add to that air drag from being on ground level and I would have to say that the more viable solution is halman's idea of a two staged launch. I suppose constructing a maglev system at a higher altitude could help, but I imagine that using a White Knight approach, or one that halman is suggesting could be more efficient. It would also be easier to adopt, as you wouldn't need to take a huge financial risk in building the rail system. Not being a professional in the matter however, I cannot say for sure that this is accurate.
 
A

Astro_Robert

Guest
Just for perspective: Arthur C. Clark actually proposed in one of his sci fi stories that a nuclear powered rail launcher to be built in the Australian Outback. The concept has been around for a while, roughly as long as the communication satellite conept in fact.

Clark, chose nuclear for power considerations and addressed the issue of radioactivity, which is why he chose the outback. If I recall correctly, there was even an interview with him where the interviewer asked about the story in comparison to more recent launchers.

More and more people are trying to find cheap aceess to space, hopefully someone will succeed in actually building one.
 
H

halman

Guest
wskinny":57kil77v said:
My proposal is simple, think of the already existing and running maglev train. Now, build a rail track, initially flat on the ground but on the final kilometers stepping up to let's say 45º or 60º. Let's assume a length of about 1000km to allow for a low G force acceleration during the process and accelerate to the needed speed to achieve an LEO, taking in account that we'll be out of propulsion as soon as we leave the tracks, meaning we'd have to accelerate to a higher speed that current propulsion systems to compensate for the speed loss after leaving the launch rail, something that isn't that hard to achieve with an increasingly high power/high frequency rotating magnetic fields.
Now, take in account that we need no rocket to put our ship into space, and the only fuel we need to carry is the one needed to propel our ship during it's mission, that alone will be a major cost reduction. Now account for the expense you wouldn't have to spend now on fuel and rocket construction. Think of the weight reduction of the total mass to be thrown into space. Finally, realize that you would be able to send spaceship after spaceship with intervals of hours instead of weeks or months, largely increasing the return pay for your investment.
Wouldn't this be a much more economically viable launching technology after the initial investment? Wouldn't it drastically reduce the cost of manufacture and launch making it affordable to endeavor in much larger and longer missions?

Am I not seeing something here?


wskinny,

Welcome to the Space.com dissing, I mean discussion, boards! I am glad to see people here be worked up enough about something to actually write about it.

However, I did not read more than the first few sentences of your post, because you advocated something which constantly comes up: Accelerating a payload to orbital velocity inside the atmosphere. It cannot be done, for reasons which are outside of our everyday reference experience.

A windstorm will tear things to pieces, and it is only packing winds of less than 200 miles per hour. When you get up into the miles per SECOND speed range, that wind is made of concrete. Tremendous heat is generated, and pressure waves begin to ripple through the air surrounding the object moving through it. The air you are breathing means that we have to keep the speed down while we are deep in the atmosphere, which is why the space shuttle has to throttle its engines back right after lift off. Not until it has climbed above 50,000 feet can they use the full power of all engines. (And I think that they don't actually go to full power up until about 70,000 feet.) The atmosphere is just too dense.

But that same density can be our ally, by providing aerodynamic lift, and oxygen to burn fuel with. It is by capitalizing on those qualities, instead of treating them as a hindrance, as well as keeping the demands on the orbiter to a minimum, that I believe the savings, and the safety, will come from.
 
H

halman

Guest
scootb50,

I am not advocating that the space shuttle be used for launching satellites, supplies, or other payloads. I think we should keep it just for rotating crews at the International Space Station, and the space stations to follow, as well as for lunar exploration missions, at least until we can develop a better alternative. And by better alternative, I mean something which can be reused, is capable of returning to its launch site unaided, and can be operated in the 500 dollar per pound to 120 mile orbit range. And that vehicle should be online before the space shuttle is retired.

In terms of safety, my proposal offers much greater safety than a vertically launched system. During the launch of the stack, the launch rail can stop the whole weight of the combined vehicles much more easily than it can accelerate it; after launch, the orbiter can separate and return to point of origin under its own power; after planned separation, the orbiter can return to point of origin dead stick, if need be. We have already proved that a trans sonic lifting body design is safe for re-entry, the validity of which was not affected by our trying to do it with a vehicle which almost certainly had a big hole in the leading edge of one wing.

And we are going to have to accept that launches and returns occur in realms of speed and altitude where guaranteeing individual safety is impossible, just as airlines decided not to hand out parachutes. Launching vertically increases the dangers the crew are exposed to, by putting them at rest on top of large amounts of highly flammable materials. Once they have some velocity, the options open up dramatically.
 
M

marcel_leonard

Guest
Booban":2alx0q9q said:
Isn't that how SpaceshipOne(two?) works? Only it doesn't yet go quite as high. Otherwise I think people are waiting for scramjet technology for this, from what I've read it seems to be the 'only' way. Although if that's the case, how did the engineers think to do it with the initial shuttle plans (mini version).

Ares 1 seems to be getting canceled just because it will only go to LEO when there is no space station any longer. And many have questioned the usefulness of a space station in LEO and would rather do away with it entirely, or at least build a new one further away.

So I don't get it, are we always going to have a LEO space station or not? Is there a point to manned LEO access without a space station?

We are just talking about LEO aren't we? Because I was under the impression that getting to LEO or further required totally different vehicles.


Clearly the key to low cost space delivery systems is Areospike/Scramjet engines :cool:
 
H

halman

Guest
marcel_leonard":vvqtm0zd said:
Clearly the key to low cost space delivery systems is Areospike/Scramjet engines :cool:

Perhaps that is clear to you, but it isn't clear to me. If we are launching from 50,000 feet, the advantages of the aerospike engine are minimized, because the ambient air pressure is extremely low. The scramjet is an appealing concept, but suffers the limitation of needing another engine to get it to operating velocities. Both of these technologies are likely to mature as funding for development becomes available, but their application would require extensive testing. Someday, they may form the propulsion system of a single-stage to-orbit system, but I am not interested in 'someday'.

Instead of trying to incorporate the latest technology, or the most powerful engines, I would rather take the approach of simple, proven rockets, operated at less-than-maximum power. By using multiple engines, we build in redundancy without increasing complexity. And the demands of the mission profile for airborne launching are much lower than for vertical launching, which requires thrust to weight ratios of greater than one to one. Even .75 thrust to weight ratio will work, because all that is required is to accelerate the vehicle, not to lift it.

The whole basis for my proposal is that we can reach orbit without having to require the absolute utmost of our technologies. And I am certain that we can do this in a relatively short period of time, as long as we avoid getting mired down in developing new stuff. The most radical aspect of what I am proposing is the magnetic catapult, which has never, to my knowledge, been utilized on a large scale. Everything else is simply an extension of what we have already done, even if it is by a couple of orders of magnitude.

Once we have established ourselves in space, and are making money up there, we will have plenty of time and funding for developing new technologies. I would be thrilled if my concept only turned out to be used for a few years as the result of a new technology displacing it, but, right now, I don't see any other way that we are going to be able to meet the staffing requirements of any large-scale expansion off-planet.
 

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