A cheap and easy way to space.

[neutrino78x]

How about a tiltrotor feature for the carrier aircraft, so it can take off vertically, then fly horizontally until it get the right altitude, before launching the rocket?

I claim that vertical launch is the future of airplanes, so that you can pack a lot more airliners at one airport, instead of having to build more airports. Just a crazy idea to throw out there, I think it would be cool.

Oh yeah, and the carrier aircraft should use electric propellers, instead of jets, powered by a hydrogen fuel cell.

--Brian

 

[annodomini2]

I found an interesting .pdf file here: http://www.reactionengines.co.uk/downlo ... _22-32.pdf

It details a British single-stage-to-orbit spaceplane (SKYLON) that employs a combined air-breathing turbojet/rocket engine called Sabre. The thing that caught my eye is that this vehicle has an ignition weight of 275,000 kg (605,000 lb) and a payload to LEO of 11,620 kg (25,564 lbs). The air-breathing turbojet is designed to function from speeds of 0 (take-off) to Mach 5.5 at an altitude of 26 km (85,320 ft). Beyond that it operates as a pure LOX/LH2 rocket.

An air-launched vehicle of this type might be more suitable than the (canceled) VentureStar concept for crew transport. Although the SKYLON is intended to be ground-launched, I believe the advantages of air-launching a vehicle of this type with a similar payload capacity could significantly reduce the overall weight.

Chris

It doesn't use a turbojet, it uses a LACE rocket engine or airbreathing rocket if you wish.

Liquid Air Cycle Engine

Effectively this is air launched, just the launcher goes with it.

This effectively increases the ISP of the engine as a large portion of the mass used for thrust comes from the atmosphere and so much less oxidiser is carried. Reducing the weight of the vehicle.

 

[js117]

I found an interesting .pdf file here: http://www.reactionengines.co.uk/downlo ... _22-32.pdf

It details a British single-stage-to-orbit spaceplane (SKYLON) that employs a combined air-breathing turbojet/rocket engine called Sabre. The thing that caught my eye is that this vehicle has an ignition weight of 275,000 kg (605,000 lb) and a payload to LEO of 11,620 kg (25,564 lbs). The air-breathing turbojet is designed to function from speeds of 0 (take-off) to Mach 5.5 at an altitude of 26 km (85,320 ft). Beyond that it operates as a pure LOX/LH2 rocket.

An air-launched vehicle of this type might be more suitable than the (canceled) VentureStar concept for crew transport. Although the SKYLON is intended to be ground-launched, I believe the advantages of air-launching a vehicle of this type with a similar payload capacity could significantly reduce the overall weight.

Chris

The artical was written in 2004 and now has changed to a new engine ( Synergic Air Breathing Engine ) more advanced.
link to engine New http://en.wikipedia.org/wiki/Reaction_Engines_SABRE
Link to lace OLD http://en.wikipedia.org/wiki/Liquid_air_cycle_engine
http://www.knowledgerush.com/kr/encyclo ... le_engine/
Link to SKLON http://en.wikipedia.org/wiki/Reaction_Engines_Skylon

 

[EarthlingX]

Sabre engines are a part of ESA program LAPCAT :

Wiki : LAPCAT

LAPCAT (Long-Term Advanced Propulsion Concepts and Technologies) was a 36 month European FP6 study to examine ways to produce engines for a Mach 4-8 Hypersonic aircraft. The project ended in April 2008.[1] It was funded by the EUROPA general R&D fund (rather than ESA) and cost 7 million euro.[2][3]

LAPCAT II, a 10 million euro four-year follow on project was due to start in October 2008.[1][4] The study will refine some of the results of the first study "allowing the definition of a detailed development roadmap" of a Mach five vehicle.[5]

Try running LAPCAT search on SDC, i already posted a couple of related articles, on this thread too, couple of posts up.

 

[halman]

How about a tiltrotor feature for the carrier aircraft, so it can take off vertically, then fly horizontally until it get the right altitude, before launching the rocket?

I claim that vertical launch is the future of airplanes, so that you can pack a lot more airliners at one airport, instead of having to build more airports. Just a crazy idea to throw out there, I think it would be cool.

Oh yeah, and the carrier aircraft should use electric propellers, instead of jets, powered by a hydrogen fuel cell.

--Brian

Well, if you don't think that my whole concept of a 'cheap and easy way to space' is crazy, try this one on for size:

Using diesel fuel for rockets and jet aircraft. Because of the paraffin, the waxy stuff that condenses out of diesel when it gets cold, diesel has more heat energy per unit of volume than gasoline. The problem has been to get a consistent mixture of paraffin in with the rest of the diesel, but that can be solved. There are already turbine powered generators which burn diesel. My father used to build furnaces for drying agricultural products, and they could burn diesel so cleanly that you could not even smell it in their output.

The days of cheap and easy into space will come about when we use cheap and easy to handle fuels, rather than hydrogen. Hydrogen has been selected often because it provides the highest isp, which has been essential for getting payloads into desired orbits, or desired payloads into orbits, but we can design around those limitations now. We are not in a race with the calender, so we can afford to engineer things completely, with the future in mind.

It seems to me that our path in the near future regarding access to space should be focused on a sustainable mix of reusable vehicles and expendable step rockets. We can launch our freight on the step rockets, while we ourselves fly on the reusable spacecraft. Before too long, we will stop sending freight up to orbit, but we will always need to send people up there. We have an option to conduct a dialogue with the public regarding space flight, and we should use this window to change the focus of our governments efforts from being the lead agency to that of providing the technology that will be needed to reach the goals so many of us cherish.

Don't ask NASA to go to the Moon, or to Mars. Ask them to provide us with the engines, the life support, the radiation shielding. Get the government out of the launch business, and spend our collective resources to learn how to launch more efficiently, safely, and reliably, so that the private sector can capitalize on hauling people into space. Let's see if we can't get the government to provide private industry with some research facilities in space, so that they can get a start on developing the products that will make space a good investment.

 

[csmyth3025]

...Using diesel fuel for rockets and jet aircraft. Because of the paraffin, the waxy stuff that condenses out of diesel when it gets cold, diesel has more heat energy per unit of volume than gasoline. The problem has been to get a consistent mixture of paraffin in with the rest of the diesel, but that can be solved. There are already turbine powered generators which burn diesel. My father used to build furnaces for drying agricultural products, and they could burn diesel so cleanly that you could not even smell it in their output.

The days of cheap and easy into space will come about when we use cheap and easy to handle fuels, rather than hydrogen. Hydrogen has been selected often because it provides the highest isp, which has been essential for getting payloads into desired orbits, or desired payloads into orbits, but we can design around those limitations now...

It seems to me that our path in the near future regarding access to space should be focused on a sustainable mix of reusable vehicles and expendable step rockets. We can launch our freight on the step rockets, while we ourselves fly on the reusable spacecraft. Before too long, we will stop sending freight up to orbit, but we will always need to send people up there. We have an option to conduct a dialogue with the public regarding space flight, and we should use this window to change the focus of our governments efforts from being the lead agency to that of providing the technology that will be needed to reach the goals so many of us cherish...

I agree with your thinking on this. I wonder if the SKYLON/Sabre engine concept can be adapted to use RP-! (a highly refined form of diesel commonly used in liquid propelled rockets). This question centers around whether the LOX, which the SKYLON-like vehicle will necessarily carry, can be used for cooling the helium loop in the Sabre engine. If so, this arrangement would significantly reduce the cost of engineering and manufacturing the vehicle as well as reducing the cost of operation. Since LOX is much denser than LH2, I'm thinking that the needed increase in the volume of the LOX tank would be off-set by the reduction in the size of the fuel tank.

I'm still thinking that a rail-launch system for the mother craft/orbital vehicle is preferrable, if for no other reason than the fact that it would allow the under carriage of both vehicles to be engineered for their designed landing weights - which would be significantly less that their take-off weights. The reduction in fuel consumption to achieve sufficient air speed for take-off would be an added bonus. In the case of an abort, both vehicles could dump their fuel loads prior to landing.

As I mentioned before, one of the things I like about the SKYLON/Sabre engine concept is the possibility that the Sabre engines can be "run up" during take-off and throughout the climb to altitude to assist the engines of the mother craft. This would reduce the size of the engines needed by the mother craft as well as ensure that the Sabre engines are fully functional prior to reaching launch altitude.

Chris

 

[halman]

Chris,

Rp-1 is a highly refined form of kerosene, not diesel fuel. Rp-1 contains high amounts of naphtha, which regular kerosene does not, I think.

The Skylon concept that you mentioned is very unlikely to adapt diesel as a primary fuel, because an application such as that will require the highest isp possible.

 

[Astro_Robert]

These engines you guys are discussing sound an auwful lot like RBCC (Rocket-Based Combined cycle) engines that have been around for a while. Such engines can operate as quasi-rocket type engines at low speed, ramjets at higher speed, and full rockets when above the atmosphere. This has the advantage of not having to carrying multiple propulsion systems that are dead weight during other stages of flight.

As for the 'wings' on vehicles such as LAPCAT, they are really just control surfaces, not primary lift generators. Keep in mind that the fuselage itself is shaped like an airfoil and has a large surface area. Although this shape is probably most efficient at higher speeds, it is good enough for horizontal takeoff. In fact, I believe the 1980s NASP program utilized a roughly similar shape and planform.

 

[scottb50]

Chris,

Rp-1 is a highly refined form of kerosene, not diesel fuel. Rp-1 contains high amounts of naphtha, which regular kerosene does not, I think.

The Skylon concept that you mentioned is very unlikely to adapt diesel as a primary fuel, because an application such as that will require the highest isp possible.

Diesel fuel #2 is pretty much the same as Jet A with the exception that jet-A has been filtered more to remove more water, it has a lower freezing point. RP-1 is similar to jet-B with naptha added to further lower the freezing point. Jet A1 is a middle grade used pretty much everywhere but in the U.S.

Either way they are all based on kerosene and pretty much the same thing. Back when I was flying Lears we used to have to add prist to the Jet-A to lower the freezing point, now the additives are premixed.

For a launch vehicle RP-1 is sort of overkill, the rapid flow rate and short duration of flight would make contamination moot.

 

[csmyth3025]

Chris,

Rp-1 is a highly refined form of kerosene, not diesel fuel. Rp-1 contains high amounts of naphtha, which regular kerosene does not, I think.

The Skylon concept that you mentioned is very unlikely to adapt diesel as a primary fuel, because an application such as that will require the highest isp possible.

Diesel fuel #2 is pretty much the same as Jet A with the exception that jet-A has been filtered more to remove more water, it has a lower freezing point. RP-1 is similar to jet-B with naptha added to further lower the freezing point. Jet A1 is a middle grade used pretty much everywhere but in the U.S.

Either way they are all based on kerosene and pretty much the same thing. Back when I was flying Lears we used to have to add prist to the Jet-A to lower the freezing point, now the additives are premixed.

For a launch vehicle RP-1 is sort of overkill, the rapid flow rate and short duration of flight would make contamination moot.

Aside from maximizing ISP, I think one of the concerns for reusable engines such as the SABRE engine is the build-up of residuals which might require tear-down of the engine beween flights. This would increase the per-flight costs significantly. On the issue of ISP, if a SKYLON-like vehicle were to be air-launched, LOX/RP-1 might suffice and would be a lot cheaper that LOX/LH2.

Chris

 

[kook]

The Skylon is designed to harvest oxidizer from the atmosphere. Hydrogen is the only fuel with enough heat capacity to supercool the incoming air and provide enough isp for the concept to work. RP-1 or kerosene is completely unsuitable for this design.

 

[halman]

The Skylon is designed to harvest oxidizer from the atmosphere. Hydrogen is the only fuel with enough heat capacity to supercool the incoming air and provide enough isp for the concept to work. RP-1 or kerosene is completely unsuitable for this design.

We can make access to space cheap and easy, in a short period of time, if we concentrate of on proven technology, used in applications which are new, to overcome the limitations that currently exist in space flight due to vertical launching. We are not utilizing the advances that have been made in aeronautics over the last fifty years to any effect in reaching for space, even though tremendous strides have been achieved in lifting weight and hauling it around the world. When the Saturn 5 rocket was designed, the Boeing 707 was just being proven, and the biggest freight aircraft had propellers.

Designing for the specific purpose of carry weight to altitude results in aircraft which are substantially different than any that have been seen before, and allows payloads to be carried which are much larger than a regular aircraft with the same engines can lift off with. We need to say to our engineer friends, "How big would a wing have to be to carry 3 million pounds?" "How much power would it need in order to be able to climb at 1,000 feet per minute?" "What would the stall speed be at maximum take off weight?" These are questions which can be answered by formulas and computation, which result in numbers that describe something which has never existed before.

By strictly defining our goal, we can narrow down the list of solutions to what is achievable, and which ways it can be achieved. Once we establish that something can be done, we make it easier to do it. We know that a spaceship can reach orbit with very small engines once it is high enough in the atmosphere that it can use those engines to go faster, not to hold itself up AND go faster. If we make the payload just a few thousand pounds, the size of the vehicle comes down considerably compared to something like the space shuttle. If all that we set out to do is to carry people into orbit, and to return them to their launch point, we can achieve our goal. It doesn't have to be a huge goal, like taking the folks to the Moon, just a little hop to the other side of the atmosphere. Only a couple of hundred miles. But those are the hardest miles in space flight, and they are the ones that are preventing us from moving forward with doing stuff off planet.

 

[scottb50]

These are questions which can be answered by formulas and computation, which result in numbers that describe something which has never existed before.

Compared to a C5B a 3,000,000 pound takeoff weight would require nearly a 700 foot span, compared to the A-380 it would need to be roughly 640 feet, figuring the same wing loading. Chord could be increased with the longer span but drag and aspect ratio, needed to reach effective altitudes would probably keep it well over 500 feet.

 

[halman]

These are questions which can be answered by formulas and computation, which result in numbers that describe something which has never existed before.

Compared to a C5B a 3,000,000 pound takeoff weight would require nearly a 700 foot span, compared to the A-380 it would need to be roughly 640 feet, figuring the same wing loading. Chord could be increased with the longer span but drag and aspect ratio, needed to reach effective altitudes would probably keep it well over 500 feet.

There is a loss of lift encountered when a wing is swept back to reduce drag. Most large aircraft are swept wing, because they are going to be traveling at high speed for long periods of time. If a C-5 had straight wings, they would be much shorter than the swept wings, I believe. My guess is that a wing about 300 to 350 feet across would provide the required lift, if designed for lift exclusively, and not speed. Drag can always be compensated for with more power in an application such as this. And who says that an aircraft must have only a single wing? The biplane disappeared because engine performance made higher speeds possible, so enough lift was generated with a mono-wing design. If we want lots of lift, add another wing.

The only thing that I can be sure of is that the carrier wing will look like no other aircraft, because no other aircraft will have been designed for the kind of work the carrier wing will perform. As much of the airframe will be incorporated into the wing as possible, to keep drag to a minimum, so the cockpit would be under the leading edge of the wing, inside the wing. Or, it might be a Remotely Piloted Vehicle. The use of a launch rail catapult would make take offs at speeds in excess of 300 miles per hour possible, if required. Boundary Layer Control is another option for increasing lift.

But the carrier wing should be the simplest part of the launch system, using off the shelf engines. Fabrication using carbon composites is desirable, to minimize weight, but exotic materials should be avoided, initially, at least. One carrier wing could service 6 or 7 orbiters, because of rapid turnarounds. The aircraft will have no other application, I believe, being too specialized to do anything but carry orbiters to altitude. But, if using them will cut launch costs by 1/2, they would be well worth it.

 

[scottb50]

My guess is that a wing about 300 to 350 feet across would provide the required lift, if designed for lift exclusively, and not speed. Drag can always be compensated for with more power in an application such as this. And who says that an aircraft must have only a single wing? The biplane disappeared because engine performance made higher speeds possible, so enough lift was generated with a mono-wing design. If we want lots of lift, add another wing.

True the sweep of the wing is to allow higher speeds, what the aspect ration refers to is the ratio of the length to the chord, the width of the wing. If you notice gliders have high aspect wings which allows them to generate maximum lift with minimal drag.

A good example is the Lear 25 compared to the Lear 39, same inner wing but the 35 has tip tanks while the 39 has winglets. The winglets serve the same purpose as if they were flat and extended the wing span, they increase the aspect ratio. Where this applies in this discussion comes from comparing performance. The 25, on a standard day can initially climb to 390 and gradually climb to 450 as fuel is burned off. The 39 can climb to 450 initially and reach 510 well before the 25 could get to 450.

Other then a canard configuration multiple wings would create excess weight and drag, not a very good idea. On thing I've seen is a triangular wing with the tips meeting it the top, I think NASA flew a prototype of this configuration at one point.

Found this:
http://www.abovetopsecret.com/forum/thread192824/pg1

 

[EarthlingX]

Wiki : Closed wing

Googling 'joined wing' is very productive. YouTube also gives plenty.

An old patent :

Joined wing aircraft United States Patent 4365773

Phantom works, McDonnell Douglas :

[youtube]http://www.youtube.com/watch?v=aP6t0gEYZwQ[/youtube]

 

[voyager4d]

What year was this project Diamond?
Can't find any other informations about it.

 

[EarthlingX]

What year was this project Diamond?
Can't find any other informations about it.

This year, or at least i think so. First comment on YouTube is February 07, 2010, there's some more info in the video, if you are interested, but i would not hope for a lot, since, as it is said, it is a small budget project, by Phantom Works. They already talk a lot, considering.

Similar, older, i'm not so sure how much related :

[youtube]http://www.youtube.com/watch?v=NtMkbi_D2TU[/youtube]

I saw a concept plane with closed wing for air-liners, but can't find it now. It seams, a lot of people are interested in the idea, many working on it.

Example :

[youtube]http://www.youtube.com/watch?v=X6A1mSh0DB8[/youtube]

A lot of different images :
http://images.google.com/images?q=joine ... CA8QsAQwAA

http://aerospace-technology.blogspot.com/ : Airbus Future Airliner Concepts

Monday, December 29, 2008

some more from Airbus, above one too :

AIRBUS STUDIES FUTURE AIRLINER CONCEPTS

This topic would probably require a thread in Aviation, if it's not already there, but 'box wing', 'closed wing' or 'joined wing' don't give any related results.

Example link, which might fit there :

http://www.rcexperimental.com/concepts.html

 

[neutrino78x]

Hydrogen is the best fuel because of pollution concerns. What we need is a way to store a large amount of it without significant leakage. I heard they were working on using the buckyball molecule for that? C-60?

--Brian

 

[neutrino78x]

C-60/fullerene on wikipedia.

--Brian

 

[scottb50]

http://aerospace-technology.blogspot.com/ : Airbus Future Airliner Concepts

Monday, December 29, 2008

While interesting I haven't seen where it has shown an advantage. The fuselage attachments would add a lot of drag and the corners don't look to good either. The best winglets have very smooth deep angles. Aspect ratio still remains the driving force and the box wing doesn't address that. It might fit in to gates better but I doubt it could climb to the most efficient altitudes for best performance.

Either way a long thin wing with big winglets would give the best results. Engines in the center section rather then in pods would also make more sense. Only one area needing to be overbuilt to handle the stress of landing gear and engines rather then multiple areas. Why the 737 is better then the DC-9, it doesn't have to have two areas reinforced, the gear and engines attach to the same structures.

 

[Astro_Robert]

EarthlingX,

The concept of a closed wing for airlingers is known as Blended-Wing-Body. Boeing has been toying with it for like ~7 years with some lifeline funding from NASA. Their original concept was to make an Ultra-jumbo jet even bigger than the A380. I do not know if they have progressed beyond small scale model testing. I will also search aviation forums to see if there is a post I can add this too their.

I do not know if such a planform would meet the OP's desire for a carrier wing, but certainly the large flat fuselage helps it generate a lot of lift.

 

[EarthlingX]

http://aerospace-technology.blogspot.com/ : Airbus Future Airliner Concepts
Monday, December 29, 2008

While interesting I haven't seen where it has shown an advantage. The fuselage attachments would add a lot of drag and the corners don't look to good either. The best winglets have very smooth deep angles. Aspect ratio still remains the driving force and the box wing doesn't address that. It might fit in to gates better but I doubt it could climb to the most efficient altitudes for best performance.

That's probably why there's not much after this. I think i saw somewhere in those links mentioning experiments with joined wing configuration using 747, but since i can't find it ..

I wonder what could come out of this, if you could watch it through Burt Rutan's eyes ? For 15 min, let's say ?

Either way a long thin wing with big winglets would give the best results. Engines in the center section rather then in pods would also make more sense. Only one area needing to be overbuilt to handle the stress of landing gear and engines rather then multiple areas. Why the 737 is better then the DC-9, it doesn't have to have two areas reinforced, the gear and engines attach to the same structures.

What about top wing part forward, with engines hung under top wing, and vector-thrusted exhaust above the bottom wing, forward wing for stabilization - if i can avoid drawing, but the point is to stabilize lift and thrust forces around centre of gravity.

Yes, i know about blended wing, and i see no reason why fuselage would not be able to give some lift in the above example.

 

[csmyth3025]

As I understand it, the Russian AN-225 has a payload capacity of ~550,000 lbs using 1980's materials and power plants, and using a pretty standard design. Scaled Composites has shown the possibilities of a purpose-built air launch platform. The launch weight of a fully orbital, reusable crew vehicle such as the SKYLON is, according to Reaction Engines, Ltd:

"It's a pretty unique concept," says Mark Hempsell, director of future programmes at Reaction Engines. "I think at the moment it's the only realistic way to make aircraft vehicles that go into space."

The design should be sufficient to power a 43-tonne plane that can loft 12 tonnes of payload into low-Earth orbit, about half what the space shuttle can carry, the firm says.

If my math is correct, 43 metric tonnes comes out to about 95,000 lbs. It would seem that we have the capability with our existing aircraft designs and materials, and our existing power plants to enable the construction of an air launch platform robust enough to provide the means for a reusable crew launch and return system.

The big question at this point is what type of orbital vehicle is best suited and most economical for routine orbital flights. As a layman, I like the SKYLON/Sabre engine concept (as an air launched vehicle). An aerospace engineer may see flaws in this concept. If so, I'm anxious to hear what they might be.

Chris

 

[halman]

csmyth3205,

In the past, design criteria have centered around getting the maximum possible weight into orbit, or to a final destination. Every aspect of the design is oriented around that goal, so that maximum performance motors and propellants are used, minimum possible crew support is provided, and things such as landing characteristics are allowed to suffer. This philosophy lead to capsules instead of lifting bodies, parachute landings, and disposable launch vehicles.

If we set out to build a vehicle which can ascend to orbit, support a dozen people there for a few days, and return to land at the launch site, we limit our designs to some kind of lifting body. Total reusability means all propellants must be enclosed in the orbital vehicle, and engines must be able to withstand repeated operation, as well as a thermal protection system which does not require ablation or extensive repair after flight. Pure lifting bodies are extremely hard to control at low air speeds, so some kind of wings are needed. Perhaps retractable wings would be worth the additional weight, or a combination of fixed wings and extensions which are used for the final approach and landing.

Rocket motors which are robust, easy to service, modular, and restartable are essential, and propellants must be stable for prolonged periods, due to the climb to launch altitude. This almost certainly excludes liquid hydrogen, and kerosene seems to be the best fuel for the application.

I find it unfortunate that our national space policy does not revolve around being able to get into space and returning reliably and cheaply. We should be learning new things, not repeating what we have already achieved.