A cheap and easy way to space.

[csmyth3025]

What pisses me off is that NASA has just been sitting around wasting money while they were flying the shuttle yet they had no backup plan! As mentioned, they built the X-33, X-34, X-37, HL-20 and a couple of other viable alternatives only to cancel each one a couple years into development! If they had just gone through with one of those we wouldn't be in this situation, but they spent billions half producing several easily possible designs. Also, NASA seems to over complicate everything when it comes to manned flight. Why will it take them 4-5 years to man rate and build a capsule for a Delta IV or Atlas V? I don't understand, why the wait?

Remember that, despite all its good works and good intentions, NASA is still a huge Federal agency. It suffers from the same "program driven" short-comings that all government agencies have. This is the main reason so many of us believe that private industry will be the primary driver for the utilization of space.

Chris

 

[neilsox]

It seems to me we can gently boost the ISS to a higher orbit, or even a much higher orbit. We have not done this as the support craft such as the space shuttle suffer drastic payload reductions to higher orbits. Also the radiation dosage of the ISS crew increases at higher altitudes due to moving into the lower edge of the Van Allen belt. Neil

 

[SciFi2010]

After reading and seeing some of the interesting designs in this forum I think there’s something missing in the equation here. Most of what I saw here are unique and complex designs, which are probably time consuming and expensive to develop and to manufacture. Even the Blended Wing Body is decades away from realisation (maybe never). The WhiteKnightTwo from Virgin Galactic is a step in the right direction but is still not large enough to launch orbital space vehicles. If a giant fuel-efficient lightweight airplane that can carry an orbital rocket or a future spaceplane on its back or under its belly to a height of 50,000 feet or more and is an efficient way into orbit, then why do we not build a flying “catamaran” with parts that are bought of the shelve from for example Boeing or Airbus? I think the main problem is that such a heavy carrier airplane has to able to do more then only space launch to be commercially viable. In the first instance it should be a simple design that is able to carry any heavy cargo as high as far and as fuel-efficient as possible, while its development-, manufacturing- and operational costs & time should be low. The main task of such an airplane should ofcourse be launching manned/unmanned space vehicles into orbit, but it should also be flexible enough to carry any heavy cargo around the world. Next to reliability, reusability and the possibility of multiple applications, a simple design should also be more replaceable. The dramatic accidents with the Challenger and Columbia for example showed us a Space Shuttle can’t be replaced simply and quickly with a new Space Shuttle, because the Space Shuttle was a unique, complex and expensive design. At this moment I’d rather see a whole fleet of inexpensive flying catamarans that are able to carry 4 times the load of an Antonov airplane to a height of 60,000 feet than a few expensive supersonic/hypersonic airplanes carrying a moderate amount of load. If such a giant carrier airplane with a high flight-ceiling could also be sold outside the US for example to Europe and Japan, a constant operational production line could be possible, which would be essential in lowering the manufacturing costs. These carrier airplanes could be used:
1. To carry heavy cargo anywhere around the world (with for example a detachable aerodynamic container to carry airplane parts, goods, etc…)
2. For scientific research in the higher layer of the atmosphere or to launch experimental aerospace vehicles
3. To launch hypersonic manned vehicles for leisure or international transport
4. To carry rockets for unmanned launches into orbit. The next step would be to combine the concepts of a “WhiteknightX” airplane with a “FalconX”/DragonX” to lower manned access to space especially for civilian space transport. (See YouTube: t/Space Full Concept of Operations by deanfilip)*
5. To transport future (SSTO) spaceplanes or to support spaceplanes in the first stage of launch into orbit like the Skylon. (See YouTube: The Future of Space Travel by steamburn123)

This is not very much different what B. Rutan & R. Branson has in mind for the future I think, but a carrier airplane like the WhiteKnightTwo has to be scaled up in size and production first to become meaningful in the orbital space industry. This also has the advantage that such airplanes could accelerate the R&D of spaceplanes with Sabre-like rocket engines. Maglev ground launch systems to support the first stage of launch can always be introduced in a later stadium.

* I especially like the Russian designs although they have never been realized. Check it out!
http://www.ussr-airspace.com/index.php? ... cts_id=703
http://www.ussr-airspace.com/catalog/im ... 121248.jpg
http://www.ussr-airspace.com/catalog/im ... 162443.jpg
http://www.ussr-airspace.com/catalog/im ... 161048.jpg

 

[csmyth3025]

The Russian "Project 52" aircraft were 80's design concepts (scale models). Actually building them is going to be expensive. It's interesting to note, though, that it took the private sector to use the concept. NASA and the Russian space agency have pretty much stuck to the same game plan for the past thirty years.

Chris

 

[vulture4]

Whether air-launch to orbit is feasible for human spaceflight is impossible to say without further development of the concepts and testing some actual designs. Most rocket-propelled launch vehicles have a lift/weight ration of greater than 1 and do not use wings to provide lift during the climb; even the Pegasus, which does, climbs at over 45 degrees. The main advantage of air launch is simply to reduce gravity and air drag losses.

The X-34 program would have resolved many of these issues if it hadn't been canceled in 2001, another NASA decision which seems to have been made on the NASA side with a rather arbitrary set of objectives and constraints, i.e. NASA decided "verification" of the autoland capability was needed and "single string" systems weren't acceptable, so rather then let the contractor accept theses "risks" that the contractor had judged acceptable they decided the cost would be too high to meet their own new requirements and so canceled the entire program! Since virtually all the costs were sunk at that time, this meant taking a program that required no additional funds and had a 90% chance of success and converting it into a program that had a 100% probability of failure!

Why was the program canceled when cancellation guaranteed failure? Why did NASA refuse to allow Burt Rutan to fly the prototypes at his own expense, as he oferred? I could be wrong. If anyone knows who actually made this decision for NASA and can persuade him/her to provide an explanation, I'd be very interested. But if no one can provide information to defend this decision, we can only conclude that the decision was wrong.

 

[SciFi2010]

Although a reusable SSTO with low manufacturing and operational costs would be ideal I think the combination of a carrier airplane and a rocket and/or spaceplane would be the next best thing to lower the costs of manned access into LEO. While there’s almost no funding and political will at the moment for the first option the last option can be developed by the commercial aerospace industry, because most of it is common technology. This makes the R&D and the funding required doable for even a small company like Virgin Galactic. For now it is unrealistic for a company like V. G. to develop a mega carrier airplane & (rocket&) spaceplane for orbital launches. The up-scaling of the size and production (& technology) of their carrier airplane & the spaceplane depends a lot on their business strategy and the future development of the aerospace market. To develop the commercial aerospace market all depends on:
•how cost efficient the commercial aerospace are now and will be in the future in developing & operating the means to travel into space and inhabit space (this also includes the R&D and manufacturing costs of the airplane industry)
•how many people (or countries) are able and willing to pay for these prices that are offered by this industry in the short and (middle-) long term

At the moment V. G. will have to be focused on surborbital leisure and point-to-point transportation, because the costs are relatively low compared with orbital launches and suborbital transportation doesn’t need space destinations (like space-stations or colonies). If VG can keep their development and operational costs under control they could earn their investments back fast. Then the prices could drop and the demand for suborbital transportation could grow. When the demand for suborbital transportation grows VG will be able to attract more private and government funding (or VG could consider enlisting itself on the stock market). This will give VG the possibility to upscale the size, production of their carrier airplane & the spaceplane, which will drive prices even lower and attract more potential customers, etc…. If this process continuous the carrier airplane of VG could become large enough to launch an orbital (rocket &) spaceplane (for example with torodial/linear Aerospike or Sabre rocket engines). The emergence of multiple inflatable BA spacestations as possible destinations in LEO will certainly increase the demand and this would be an interesting cheap alternative. I also wonder if it is possible to design most of the heavy cargo in such in a way that it can be divided in parts small enough to fit these kinds of launch systems. The separate parts could then later be assembled in LEO or in a LEO spacestation with or without robots. A (robotic) assembly line in space…?

That is also why I think the X-33 or its technologies could appear again, but that will depend on the success of the commercial aerospace industry.

 

[Valcan]

Although a reusable SSTO with low manufacturing and operational costs would be ideal I think the combination of a carrier airplane and a rocket and/or spaceplane would be the next best thing to lower the costs of manned access into LEO....................

That is also why I think the X-33 or its technologies could appear again, but that will depend on the success of the commercial aerospace industry.

Thats one of the things i like about this. It doesnt require a HUGE jump in technology or manufacturing to produce. We have built essentually all of it in a different form at one time or another.

 

[frodo1008]

Valcan and others here. I do think that you have discovered the true path of the future of space travel from the Earth's' surface to at least LEO. Also, from everything I have seen about the man, Burt Rutan also shares your vision.

First he is at present starting to tests on the Spaceshiptwo configuration to take many (relatively wealthy at first, but the cost will come down over time) people up to the edge of space in a sub orbital flight, returning to the same place where they started.

Next (and I am equally certain that plans are already well underway for this step) there will be a Spaceship three that will take passengers not just back to the place where they entered sub orbital space, but very rapidly take them (in less than two hours I would think) to any prepared airport anywhere on the surface of the Earth. Such a project would be so huge that I am also certain that even the redoubtable Rutan will find himself probably working with the likes of Boeing to make it a reality within the next decade.

Then it would be a relatively small step to build and operate vehicles that would also be carried up by a carrier aircraft, but then go all the way into LEO at about 200 miles up. I think that I am being somewhat conservative by stating that this should take place within two decades from now, or by 2030 at the latest.

As a final step, I would think that eventually somebody is going to develop the true Holy Grail of such craft in a vehicle that can take off from any relatively prepared civil airport and either go rapidly to another such airport on the Earth's surface, or all the way to LEO without needing any boost from any other craft. This was the dream of NASP around the year 2000 or so, and should be fully operational by the year 2040 at the latest.

Such a craft would quite probably be of a wave rider type of design with small retractable wings for landing and take off. Be provided with conventional jet engines for landing and take off up to about 50,000 feet and a velocity of about Mach 2 to 3. where a form fitting relatively small thrust aerospike type of rocket engine would boost it to about Mach 4, then a hypersonic engine would take over up to Mach 15 or Mach 20 or so would be used. Where finally, the linear aerospike would finish the flight to LEO up to the 25 Mach of orbital flight.

While certainly not impossible, and even quite probably the future this scenario is a VERY challenging one! Especially when you place the restriction on it that it should bring the cost of placing a pound to LEO down to initially less than $1,000 per pound, and eventually much lower.

Even so, I see it happening in the time frame that I mention or even less as very powerful forces are at work in this direction right now. One of these is the pure drive created by the capitalistic drive to bring these costs down to open up the incredible financial gains to be made by doing this, and the other is the desire (for its own purposes of surveillance, if nothing else) of the US military to develop true hypersonic aircraft.

And other private capitalistic people such as Bigelow will be providing the destination space station(s) to take all of these people up to. We will open up the way to a true space faring civilization, of that I am the most certain of.

My only personal sadness in all of this is that at the age of 67 now, I probably will not live long enough on this Earth to see it.

But I will always have the great satisfaction of having been one of the 400,000 or so people that directly helped originally start all this by placing men on the moon with the incredible Apollo project!

May everybody have a truly wonderful and safe Fourth of July!!!

 

[EarthlingX]

My only personal sadness in all of this is that at the age of 67 now, I probably will not live long enough on this Earth to see it.

Statistically, i guess you have quite good chances for at leat 20 years more, and in that time medical technology might change so much, that living up to 100ths will be more common, which gives you another 20 years, and then ..

Just stay with us, and avoid meteors, spacecraft, or UFOs falling on your head, if possible

May everybody have a truly wonderful and safe Fourth of July!!!

 

[frodo1008]

Thanks very much, I will try to do just that! I do hope to at least be around long enough to see the beginning of the true "age of space" for all mankind at the very least!

Once again, thanks for caring!

 

[halman]

Now, we do? Show me the existing facility or vehicle. Straight up is the least expensive and, if done right the safest approach. With a side mounted second stage, firing during launch anyway, escape would be pretty easy. A separate rocket motor for the crew module would allow zero-zero escape capability in a worst case.

A zero-zero escape capability requires sending the crew module over 1 mile away from the launch pad, while escape capability during ascent requires separation under extreme aerodynamic stress. These requirements add weight, in the form of structural reinforcement, additional engines, and recovery apparatus. My proposal does not need a zero-zero capability, because the system does not involve sitting on top of, or next to, a rocket powerful enough to lift itself and a payload straight up. At every point in the launch, there is abort capability, whether it be the launch catapult stopping the stack, or the orbiter lighting up its engines and flying off the back of the carrier wing, or the orbiter making a circular flight to land dead-stick at the point of origin. The orbiter could conceivably fly off the back of the carrier wing while the wing was still on the catapult, although that would require more powerful engines than I believe is needed.

The expense involved in launching people straight up is not so much the additional engineering, redundancy, and safety systems, but the number of people required to monitor all the systems, and to make instant decisions regarding go/no go, the demands for weather to be excellent, the range safety issues, and on and on. When an Atlas or a Delta rocket lifts off, there are about 1/4 as many people involved as there when a shuttle lifts off. The same was true back in the days of the Apollo program. Putting people on top of that much explosive propellant means taking every precaution possible.

If we can make a launch as routine as an airliner taking off, without concerns about the Thermal Protection System getting blasted by rain drops at 1 mile per second, or a boat being in the restricted zone, or a zillion other things that impact on a launch, we can cut the costs down. A lot.

 

[halman]

SciFi2010,

Perhaps you have missed the point regarding the design of the carrier wing. It would never serve as a long-haul cargo aircraft, because the wing must be straight to achieve the greatest lift, which increases drag, so the vehicle would be terribly inefficient on long flights. Consider a semi-tractor: It is designed to do one thing, and one thing alone, and that is to pull and support a trailer which carries a lot of cargo. We can add a house to back of it, put lights all over it, and paint it wild colors, but it is still going to be a tractor, which handles poorly without the trailer, gets rotten fuel millage, and is uncomfortable to ride in.

Plus, the design I propose could never land with a large cargo, because the undercarriage would not support it. To be able to land with a payload of a million pounds, you will have to have an undercarriage which will weigh hundreds of thousands of pounds. Plus, the fuel capacity should be just enough to get the orbiter to launch altitude, plus a small reserve, as well as enough to fly back and land. Adding range would dramatically reduce the payload.

Yes, the design that I purpose is unique, but the application is also unique. However, it is not complex, quite the opposite, I believe. Instead of massive turbo pumps to fuel huge engines, pressurized fuel tanks could probably suffice. The wing would be extremely simple, compared to a 747, for instance. Everything in my proposal is based on technology that has been proven, and is understood. The single most challenging part is the Thermal Protection System, which needs to be more advanced than the one used on the shuttle, because having to hand fit every tile is too labor intensive. I believe that NASA has figured out how to get around that problem, although it was never applied to the shuttle because of cost.

The fundamental philosophy of my design is simplicity, based upon a narrowly defined mission. Yes, the system could be scaled up to haul cargo, and I believe that it ultimately would be. But first, we have to get people into orbit in numbers large enough to justify sending cargo up there. And this is going to require substantial funding, because the jump from sub-orbital to orbital is huge. We can get to space without having to go any faster than 1 mile per second, and we probably could do it going even slower. But to reach orbit we HAVE to go 5 miles per second, which means that coming back we have to get rid of a lot of energy. Re-entry is the hardest part, because we need to be able to fly the vehicle to a landing, instead of just dropping it in the ocean.

Probably I am wrong, but I believe that NASA abandoned the programs mentioned above because they would have required too much money to build up into a workable replacement for the shuttle. NASA has been hamstrung by a lack of funding since before the shuttle flew, and has constantly had to make a choice between flying and building something new. Perhaps Obama can force Congress to shake loose a few billion more, so that the agency can do both, but I am not holding my breath. If only we could get people to understand that the answers to the problems of pollution, climate change, and resource exhaustion lie right above our heads, not in learning to do without.

 

[scottb50]

If we can make a launch as routine as an airliner taking off, without concerns about the Thermal Protection System getting blasted by rain drops at 1 mile per second, or a boat being in the restricted zone, or a zillion other things that impact on a launch, we can cut the costs down. A lot.

Hopefully it will be as routine as an airliner taking off but an airliner taking off is more of a risk then a horse drawn cart. A horse failure could lead to uncontrolled driving and a crash. Even with airplanes you think you have thought of everything and then something happens.

For manned flight I was thinking a Second stage, piggybacked on the First stage could power a vehicle to an altitude any shrouds could be separated and the vehicle could make a powered approach and landing. The First stage crew would need an ejection Module, like the F-111, but that pretty simple.

Like the X-37 put a shroud around the vehicle then conditions are not a problem, wings obviously cause problems so cover them.

 

[SciFi2010]

Halman,


The (relative) fuel consumption and range of an airplane-flight is not only determined by the aerodynamic shape of an airplane, but also by its engines, weight (materials and design) and at what height and speed the airplane is flying. If a subsonic shaped airplane would have enough thrust to fly at supersonic speeds it would never be as fuel-efficient as a supersonic shaped airplane (and vice-versa of course), because of the larger drag (/airlift) of a subsonic wing. A carrier airplane with long straight wings flying at the right speed and height is almost floating in the air and should be able to reach long distances with the highest fuel efficiency. (Just take a look at for example the airplane of the late Steve Fossett or the U2 spy plane.) The only disadvantage is the slow speed and the longer ride.

Besides that I wasn’t suggesting that we should build a flying carrier wing that is shaped like a stretched out surf-board and is only able to fly at low subsonic speeds. (Although the wings of the Whiteknighttwo are almost straight and they are functioning fine.) The Russian designs and the multiple purposes I mentioned are just examples. I do have to admit that a carrier airplane that is able to take full advantage of airlift at subsonic speed in the first 10 km of the atmosphere and is able to fly at supersonic speed above the 10 km of atmosphere (10% airpressure) is a more realistic approach to achieve cost-efficient air-launch into orbit, if we imagine that the Space Shuttle uses almost half of its fuel just to reach 1000 mph (from http://en.wikipedia.org/wiki/Rocket_sled_launch). The question is then what kind of paths can be taken to realize a carrier airplane and an orbital spaceplane, both technically and financially. I think a carrier airplane (with parts that are bought of the shelve) that can be used for multiple purposes (with some adjustments) is less dependent on government funding. If it is a unique design with a unique application it may even be more difficult to gather the (private/government) funds than to do the the R&D. That was my main criticism actually. Not that the idea itself was wrong. That is why I also think Scaled Composites and Virgin Galactic have the potential to design a HTHL (Horizontal Takeoff and Landing) 3- or 2-STO RLV by expanding their business opportunities, but it will take time. The aerospace industry just can not expect for government to come with more money. Every time the government spends more it has to borrow more from the money market and leaves less “space” for private companies to borrow. This government has to cut spending to cut the deficit, without harming the economy too much. It is very clear now that the consumers (who are able to spend) will not spend and the business community (, who now have vast reserves) will not invest if the deficit keeps on growing. Economy is also psychology and confidence has to be restored. That’s why I also think aerospace should contribute to the economy and society instead of being another government expense.

 

[halman]

Maybe I am being naive, but I don't think that the carrier wing will be all that expensive to build. And only a few need to be built, as the turn around time will not be very long, so one carrier wing could support 5 or 6 orbiters. The majority of the expense in the system that I purpose would be in the fleet of orbiters, which eventually would number close to 20, if the system works as I envision it. But we don't need to build more than 2 or 3 to begin with, and a single carrier wing, as well as the catapult and landing strip. Once the system is proven, I think that the private sector would be more than willing to invest in building more components.

But this system will only be viable if a Heavy Lift Launch Vehicle is available to boost the big stuff, or lots of small stuff all at once. We need the capability to launch a decent sized portion of a space station in one shot, so that it can be brought up to operational status in a short time. Bigelow's inflatable station elements would compliment what I purpose, because a 120 ton launch would orbit a station needing 10 to 15 people to operate properly. The whole idea of my proposal is to make it possible for the private sector to build and operate their own space stations.

There is several trillion dollars in capital chasing profit, any profit, in the world right now. Diverting a few hundred billion of that into space would be easy, if we could convince the investors that there is a way to make a profit. Right now, they look at the International Space Station and shudder, because it has taken a decade just to build, and numerous launches, and no real science has been done on it until just recently. Only a few people can travel to it at one time, and that will continue to be true for the foreseeable future.

The private sector wants to see the capability to launch a space station and bring it up to operational status in less than a year, as well as the ability to send 10 to 15 people to it at a time. The private sector wants to see space stations that are operated by a single company, so that results can be kept secret. The private sector has been sitting on its hands because the government has refused to provide the leadership that is required to prove that space can be profitable. BP will spend billions of dollars developing off-shore, deep water wells, because they know that they can sell the oil and make a profit. The money is there, but the leadership to show the way is not.

 

[EarthlingX]

www.nasa.gov : Emerging Technologies May Fuel Revolutionary Launcher

09.10.10

As NASA studies possibilities for the next launcher to the stars, a team of engineers from Kennedy Space Center and several other field centers are looking for a system that turns a host of existing cutting-edge technologies into the next giant leap spaceward.

An early proposal has emerged that calls for a wedge-shaped aircraft with scramjets to be launched horizontally on an electrified track or gas-powered sled. The aircraft would fly up to Mach 10, using the scramjets and wings to lift it to the upper reaches of the atmosphere where a small payload canister or capsule similar to a rocket's second stage would fire off the back of the aircraft and into orbit. The aircraft would come back and land on a runway by the launch site.

Engineers also contend the system, with its advanced technologies, will benefit the nation's high-tech industry by perfecting technologies that would make more efficient commuter rail systems, better batteries for cars and trucks, and numerous other spinoffs.

This artist's concept shows a potential design for a rail-launched aircraft and spacecraft that could revolutionize the launch business. Early designs envision a 2-mile-long track at Kennedy Space Center shooting a Mach 10-capable carrier aircraft to the upper reaches of the atmosphere. then a second stage booster would fire to lift a satellite or spacecraft into orbit. Credit: NASA/Artist concept

Different technologies to push a spacecraft down a long rail have been tested in several settings, including this Magnetic Levitation (MagLev) System evaluated at NASA's Marshall Space Flight Center. Engineers have a number of options to choose from as their designs progress. Photo credit: NASA

 

[scottb50]

http://www.nasa.gov : Emerging Technologies May Fuel Revolutionary Launcher

09.10.10

As NASA studies possibilities for the next launcher to the stars, a team of engineers from Kennedy Space Center and several other field centers are looking for a system that turns a host of existing cutting-edge technologies into the next giant leap spaceward.

An early proposal has emerged that calls for a wedge-shaped aircraft with scramjets to be launched horizontally on an electrified track or gas-powered sled. The aircraft would fly up to Mach 10, using the scramjets and wings to lift it to the upper reaches of the atmosphere where a small payload canister or capsule similar to a rocket's second stage would fire off the back of the aircraft and into orbit. The aircraft would come back and land on a runway by the launch site.

Engineers also contend the system, with its advanced technologies, will benefit the nation's high-tech industry by perfecting technologies that would make more efficient commuter rail systems, better batteries for cars and trucks, and numerous other spinoffs.

This artist's concept shows a potential design for a rail-launched aircraft and spacecraft that could revolutionize the launch business. Early designs envision a 2-mile-long track at Kennedy Space Center shooting a Mach 10-capable carrier aircraft to the upper reaches of the atmosphere. then a second stage booster would fire to lift a satellite or spacecraft into orbit. Credit: NASA/Artist concept

Different technologies to push a spacecraft down a long rail have been tested in several settings, including this Magnetic Levitation (MagLev) System evaluated at NASA's Marshall Space Flight Center. Engineers have a number of options to choose from as their designs progress. Photo credit: NASA

I don't see this fitting in with a cheap and easy way to Space. You could probably build a hundred conventional TSTO vehicles for the cost of the MagLev system.

 

[csmyth3025]

The approach I favor for the immediate future is that of a carrier wing coupled with an orbiter. Neither of these components require any huge leap in technology or even extensive R&D. The carrier wing concept has already been proven by many successful launches of the Pegasus rocket from aircraft as well as Burt Rutan's famous sub-orbital flights from White Knight One.

The Russians have for some time been trying to find a customer to finance the construction of their heavy lift HERACLES carrier wing proposed by Molniya Corporation, which can be found here: http://www.buran.ru/htm/molniya.htm (Molniya Triplane Aircraft - HERACLES)

This carrier wing has a purported payload of 450 tons. The British (Reaction Engines Ltd.) have been developing their Skylon concept, which is intended to be a single-stage-to-orbit horizontally launched spaceplane. They're projecting that the take-off weight of this vehicle (the C-2 variant), fully fueled and with a 15 tonne payload, will be 345 metric tonnes. Their site can be found here: http://www.reactionengines.co.uk/skylon_vehicle.html

It should be noted that the Skylon's proposed take-off weight and payload is based on the vehicle climbing to orbit from a standing start on a runway. Presumably the payload capacity and achievable orbital altitudes would be improved by an air launch at ~40,000 ft from a carrier wing cruising at ~500 mph. An air launch will virtually eliminate the Skylon's fuel requirement to get to the air launch altitude and speed, leaving more fuel for high altitude acceleration to orbital speeds. Also, there should be reduced landing gear structural (and weight) requirements - the fully laden Skylon at take-off (345 tonnes) would be in "captive-carry" mode. This should allow the landing gear to be designed more specifically to its weight on an Earth-return landing (~53 tonnes).

I believe a marriage of these two concepts can produce an affordable and fully reusable space taxi to and from LEO without having to "re-invent the wheel". If this approach is coupled with our established capability to produce heavy lift cargo rockets, we will have in our grasp the means by which to start building the infrastructure needed to go to the moon and elsewhere.

As far as I can see, the major problem we face is not lack of technology, but lack of funding. If this sort of project could be sold on the premise that it's needed for "national defense" it would be a lot easier. Unfortunately, the "space race" no longer seems to as important as it once was to the super powers.

Chris

 

[annodomini2]

The approach I favor for the immediate future is that of a carrier wing coupled with an orbiter. Neither of these components require any huge leap in technology or even extensive R&D. The carrier wing concept has already been proven by many successful launches of the Pegasus rocket from aircraft as well as Burt Rutan's famous sub-orbital flights from White Knight One.

The Russians have for some time been trying to find a customer to finance the construction of their heavy lift HERACLES carrier wing proposed by Molniya Corporation, which can be found here: http://www.buran.ru/htm/molniya.htm (Molniya Triplane Aircraft - HERACLES)

This carrier wing has a purported payload of 450 tons. The British (Reaction Engines Ltd.) have been developing their Skylon concept, which is intended to be a single-stage-to-orbit horizontally launched spaceplane. They're projecting that the take-off weight of this vehicle (the C-2 variant), fully fueled and with a 15 tonne payload, will be 345 metric tonnes. Their site can be found here: http://www.reactionengines.co.uk/skylon_vehicle.html

It should be noted that the Skylon's proposed take-off weight and payload is based on the vehicle climbing to orbit from a standing start on a runway. Presumably the payload capacity and achievable orbital altitudes would be improved by an air launch at ~40,000 ft from a carrier wing cruising at ~500 mph. An air launch will virtually eliminate the Skylon's fuel requirement to get to the air launch altitude and speed, leaving more fuel for high altitude acceleration to orbital speeds. Also, there should be reduced landing gear structural (and weight) requirements - the fully laden Skylon at take-off (345 tonnes) would be in "captive-carry" mode. This should allow the landing gear to be designed more specifically to its weight on an Earth-return landing (~53 tonnes).

I believe a marriage of these two concepts can produce an affordable and fully reusable space taxi to and from LEO without having to "re-invent the wheel". If this approach is coupled with our established capability to produce heavy lift cargo rockets, we will have in our grasp the means by which to start building the infrastructure needed to go to the moon and elsewhere.

As far as I can see, the major problem we face is not lack of technology, but lack of funding. If this sort of project could be sold on the premise that it's needed for "national defense" it would be a lot easier. Unfortunately, the "space race" no longer seems to as important as it once was to the super powers.

Chris

There's some abiguity over the Takeoff mass, the main page is saying 275 tonnes, the C2 version manual is saying 345 tonnes.

Sorry but relative to the cost of the vehicle and its development fuel is cheap, spending another $10-20Bil developing a 2nd aircraft to save maybe 20tons of fuel (its probably less and it's from the orbiters perspective) is naive.

The 2nd aircraft would use more fuel, simply due to the extra mass, there would need to be more ground support and maintenance such as the runway to allow this enormously heavy vehicle to take off. Which increases overheads.

Adding more complexity to the Skylon idea is pointless, as has been mentioned a fully reusable TSTO would be more cost effective than this idea.

I like where they are going with Skylon and with all new technologies there are risks, but they are answering the questions now with low cost research rather than wasting hundreds of millions of dollars/pounds/Euros (choose your preference) building the whole thing to find some unsolvable (perceived) technical challenge, e.g. X33.

 

[csmyth3025]

There's some a[m]biguity over the Takeoff mass, the main page is saying 275 tonnes, the C2 version manual is saying 345 tonnes.

Sorry but relative to the cost of the vehicle and its development fuel is cheap, spending another $10-20Bil developing a 2nd aircraft to save maybe 20tons of fuel (its probably less and it's from the orbiters perspective) is naive.

The 2nd aircraft would use more fuel, simply due to the extra mass, there would need to be more ground support and maintenance such as the runway to allow this enormously heavy vehicle to take off. Which increases overheads...

The C-2 variant is the most recent design iteration of the original (275 tonne) Skylon concept.

I think that I wasn't clear about value of the fuel and undercarriage weight savings. The Skylon, as proposed, has a limited deliverable payload to altitudes compatible with rendezvous with the ISS or other (future) space facilities at higher orbits. Any fuel and weight savings would presumably be applied towards extending its payload capacity and/or its maximum achievable orbit.

The object is to provide a vehicle that works well in the lower atmosphere (the carrier wing) and a vehicle that works well in the upper atmosphere and in space (Skylon). I think trying to design a vehicle that can do both will result in a compromise vehicle that that will not do either very well.

Chris

 

[defiant101]

how about mass driver? honestly anything other than a rocket, if we stick with rockets then i do not see how cheap access to space can happen........rockets in general will not help bring costs down in a huge way........maybe nasa should look into totally different methods or work and build upon ideas like mass drivers, or maybe x-prize can start a new competition where people submit ideas of how to make cheap access to space happen and then they will have to make a little demonstration of the concept.....i just do not see how rockets can open up space for everyone and everything....hopefully something good happens

 

[SciFi2010]

Defiant 101,

A cheap and easy way to space has not much to do with focusing on a specific kind of technology, but tries to combine and/or integrate the advantages of different kinds of technologies to lower the launch cost costs exponentially. Rockets are not a part of the problem, but a part of the solution (with the focus on part). The main problem of orbital launch is we have not focused on any possible alternatives than the use of VT rockets alone until recently, although most of these other technologies have existed for decades or longer. As if there was a curse, most of the projects to combine rocket technology with other technologies have been cancelled out of short-sightedness, political gains or events (with the lowest point the assassination of Gerald Bull, the founder of the HARP project). Aerospace has always been a tool for the military and a showpiece for politicians. Projects to really lower the launch-costs into orbit never had the same glamour and appeal as for example the Apollo-project (and now Constellation). Although these smaller projects require relatively lower investments and are of strategic importance to the economy they are “expandable” for most politicians (unlike Constellation), because the public will not even notice when they are “terminated”. In this case we want government support and not its guidance. That’s why the development of these kinds of technologies can not stay in government hands alone and have to be fully privatized on the long run if we want those alternatives to come to fruition. That is also the reason why we never had a coherent space program for LEO: these kinds of smaller projects would also have pointed out that manned launch into orbit can be roughly divided in:
1. Ground-launch (launch assist for example a rocket sled launch http://en.wikipedia.org/wiki/Rocket_sled_launch can be combined with airplane/rocket engines, Maglev and lasers),
2. The flight in the "blue" and "dark" sky (supersonic airplane & turboramjet technology)
3. The launch from "dark" sky into LEO (rocket technology and nowadays LACE or SABRE engines – airbreathing & altitude compensation).
It would not only have meant the combination of fairly common (old) technologies, but also would have meant that the transition from civilian airplane industry into the civilian aerospace could have taken place decades ago with a viable business/R&D model. What we don’t need is an Apollo project on steroids, but a supersonic airplane industry on steroids. Imagine that all the air/spaceports have runways with a launch assist, which decreases the need of large wings (weight & drag) and allows supersonic carrier airplanes to be fuel-efficient even during take off speed. The carrier airplanes for orbiters would only be needed in spaceports that are close to sea-level. Spaceports that are situated at least 2 miles above sea-level (with lower air-pressure) can have a more powerful launch assist and could allow the orbiters to become reusable SSTO’s especially when those spaceports are situated near the equator. Cargo-launch into orbit for water, fuel, food and small satellites could even be easier by combining canon, (laser-) and rocket-technology (for example the HARP and SHARP project). If we take into account that most of the future space-stations and lunar colonies in the first instance will be heavily depended on supplies from mother earth then these kinds of systems whether chemical or laser could resupply future space-station and colonies regularly at a small fraction of current prices.

 

[vulture4]

Interesting to see the Skylon launching from KSC, given the cool reception NASA gave the original HOTOL! However in reality airbreathing systems for space launch face a significant disadvantage in that the efficiency of an airbreathing system is highly dependent on speed and altitude, while a launch vehicle accelerates continuously and gets out of the atmosphere as quickly as possible. At the moment a two-stage rocket with both stages liquid fueled, capableof runway landing and fully reusable seems more feasible.

 

[csmyth3025]

Interesting to see the Skylon launching from KSC, given the cool reception NASA gave the original HOTOL!...

Did you read somewhere that there are plans to launch the Skylon from KSC? As far as I know, the Skylon only exists on paper.

Chris

 

[neutrino78x]

You could do a balloon and/or airship (zepplin) launched rocket too!!!

YouTube of a balloon rocket.

--Brian