Delta Clipper and DC-X /DC-XA.

nec208 · Dec 25, 2008

Several engineers who worked on the DC-X have since been hired by Blue Origin, and their Blue Origin New Shepard vehicle is based on the DC-X design. Blue Origin does not require the high cross range capabilities, and therefore uses a base-first re-entry profile. Also, the DC-X provided inspiration for many elements of Armadillo Aerospace's, Masten Space Systems's, and TGV Rockets's spacecraft designs.Returning the DC-X design to NASA's active research portfolio has been considered for some time now. Some NASA engineers believe that the DC-X could provide a solution for a manned Mars lander. Had a DC-type craft been developed that operated as an SSTO in Earth's gravity well, even if with only a minimum 4-6 crew capacity, variants of it might prove extremely capable for both Mars and Moon missions. Such a variant's basic operation would have to be "reversed"; from taking off and then landing, to landing first then taking off. Yet, if this could be accomplished on Earth, the weaker gravity found at both Mars and the Moon would make for dramatically greater payload capabilities, particularly at the latter destination.________________________________________________________Is Blue Origin the only one working on it or are there other companies and government working on it? <div class="Discussion_UserSignature"> </div>

exoscientist · Dec 26, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>Several engineers who worked on the DC-X have since been hired by Blue Origin, and their Blue Origin New Shepard vehicle is based on the DC-X design. Blue Origin does not require the high cross range capabilities, and therefore uses a base-first re-entry profile. Also, the DC-X provided inspiration for many elements of Armadillo Aerospace's, Masten Space Systems's, and TGV Rockets's spacecraft designs.Returning the DC-X design to NASA's active research portfolio has been considered for some time now. Some NASA engineers believe that the DC-X could provide a solution for a manned Mars lander. Had a DC-type craft been developed that operated as an SSTO in Earth's gravity well, even if with only a minimum 4-6 crew capacity, variants of it might prove extremely capable for both Mars and Moon missions. Such a variant's basic operation would have to be "reversed"; from taking off and then landing, to landing first then taking off. Yet, if this could be accomplished on Earth, the weaker gravity found at both Mars and the Moon would make for dramatically greater payload capabilities, particularly at the latter destination.________________________________________________________Is Blue Origin the only one working on it or are there other companies and government working on it? Posted by nec208</DIV>  That's good news. More companies engaged in space access will induce further research in materials and structures and to allow investigtion of the recent advance of means of producing arbitrarily large diamonds for use as ultra strong yet lightweight materials for space vehicles. For instace the cancelling of the VentureStar single-stage to orbit vehicle was because of the relatively trivial problem of finding lightweight liquid hyrogen tanks. Diamond would have a hundred to one better strength to weight ratio than the aluminum alloy tanks now used.  This would make not only the VentureStar possible but also, the DC-X variant proposal for SSTO and the Space Shuttle variant proposal for SSTO. The companies spending millions of dollars for these suborbital ventures as a commercial enterprises will make it inevitable they will investigate means of using the new advance in synthetic diamond production to turn their suborbital vehicles in fact into orbital vehicles.      Bob Clark <div class="Discussion_UserSignature"> </div>

nec208 · Dec 27, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'> That's good news. More companies engaged in space access will induce further research in materials and structures and to allow investigtion of the recent advance of means of producing arbitrarily large diamonds for use as ultra strong yet lightweight materials for space vehicles. For instace the cancelling of the VentureStar single-stage to orbit vehicle was because of the relatively trivial problem of finding lightweight liquid hyrogen tanks. Diamond would have a hundred to one better strength to weight ratio than the aluminum alloy tanks now used.  This would make not only the VentureStar possible but also, the DC-X variant proposal for SSTO and the Space Shuttle variant proposal for SSTO. The companies spending millions of dollars for these suborbital ventures as a commercial enterprises will make it inevitable they will investigate means of using the new advance in synthetic diamond production to turn their suborbital vehicles in fact into orbital vehicles.      Bob Clark Posted by exoscientist</DIV> I don't think it is material or structures that is problem but fuel efficient problem or not powerful enough.The problem with SSTO is fuel and mass ratio .The fight is to keep fuel lower than the mass .The more payload or bigger the SSTO is you get more problem do to not powerful enough. That why SSTO are small not big.If you have alot of payload or if the SSTO is big it will not get up in space but crash.They try to make SSTO small and have very little weight. I believe the problem with SSTO or most rockets is fuel efficient problem or engine not powerful enough.. <div class="Discussion_UserSignature"> </div>

exoscientist · Dec 27, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>I don't think it is material or structures that is problem but fuel efficient problem or not powerful enough.The problem with SSTO is fuel and mass ratio .The fight is to keep fuel lower than the mass .The more payload or bigger the SSTO is you get more problem do to not powerful enough. That why SSTO are small not big.If you have alot of payload or if the SSTO is big it will not get up in space but crash.They try to make SSTO small and have very little weight. I believe the problem with SSTO or most rockets is fuel efficient problem or engine not powerful enough.. Posted by nec208</DIV>  I know it is surprising but THE reason why the VentureStar was cancelled, and the reason why we don't have a prototype reusable space vehicle flying right now, was because of the trivial problem of finding lightweight liquid hydrogen tanks: X-33/VentureStar - What really happened. http://www.nasaspaceflight.com/content/?id=4180 The problems of finding lightweight reusable thermal shielding and of getting the new, advanced aerospike engines to work were essentially solved.   Note too quite likely much of the strength bearing materials in the vehicle could also be replaced with diamond. This relates directly to your observation of trying to make the mass low that has to be carried to orbit. Imagine a space vehicle the size of the space shuttle orbiter instead of weighing 200,000 lbs., only weighing 2,000.     Bob Clark    <div class="Discussion_UserSignature"> </div>

nec208 · Jan 1, 2009

What does diamond shape have do?Money is why NASA stop the X-33 .When you run into problems and takes loger than people don't like to give money when it may take 5 years to fix the problem.  <div class="Discussion_UserSignature"> </div>

exoscientist · Jan 2, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>What does diamond shape have do?Money is why NASA stop the X-33 .When you run into problems and takes loger than people don't like to give money when it may take 5 years to fix the problem.  Posted by nec208</DIV> I don't know if you're serious here or not, but it's diamond's greater strength per weight that I was talking about, not a diamond "shape".    Bob Clark <div class="Discussion_UserSignature"> </div>

nec208 · Jan 2, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'> I don't know if you're serious here or not, but it's diamond's greater strength per weight that I was talking about, not a diamond "shape".    Bob Clark Posted by exoscientist</DIV> You where saying some thing about diamond materials to lower the mass .Than saying some thing about weighing 200,000 lbs., only weighing 2,000.  <div class="Discussion_UserSignature"> </div>

dwightlooi · Jan 4, 2009

SSTO is completely unfeasible, we should just forget it until we invent something other than chemical rocket propulsion.Just run the Tsiolkovsky Rocket Equation and it should be obvious.For a 1000 ton rocket to carry a measly 1 ton payload to LEO a RP-1/LOX rocket will need to be 97% fuel at liftoff and a LH2/LOX rocket will need to be 91% fuel. This is assuming a rather generous 290 second and 420 second specific average impulse, and that about 20% of total velocity is lost to drag during initial ascent.In otherwords a rocket like the Atlas V or the Delta IV's first stage wouldn't even reach orbit with ZERO payload -- they'll reach only about 6000 m/s, well short of the 7800 m/s require for LEO. The fact of the matter is that the only way to get a 91% fuel fraction rocket is to use a balloon tank and we don't know how to build a 97% fuel fraction vehicle, period!So, an SSTO vehicle will be very expensive and fragile and will need to be the size of an ICBM to the size of a baseball bat to lift a peanut into orbit. And, we are not even talking about reusability and carrying thermal protection and aerodynamic shaping for re-entry. Add those things on and you are asking for an engineering impossibility -- something akin to creating a fighting vehicle with armor plates that weigh less than stryofoam but is harder and stronger than steel.

nec208 · Jan 5, 2009

See my other post There could be 3 problems why SSTO has not worked.1.not fuel efficient2.crude engine ( lack of power)3.propulsion  problem.We are just larning how to get up in space and back.I'm sure a car in 2009 has a better engine and more fuel efficient than a car from 1905 or a airplane from 2009 has a better engine and more fuel efficient than 1905..Same with rockets if we inprove the engine and make it more fuel efficient. <div class="Discussion_UserSignature"> </div>

exoscientist · Jan 5, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>SSTO is completely unfeasible, we should just forget it until we invent something other than chemical rocket propulsion.Just run the Tsiolkovsky Rocket Equation and it should be obvious.For a 1000 ton rocket to carry a measly 1 ton payload to LEO a RP-1/LOX rocket will need to be 97% fuel at liftoff and a LH2/LOX rocket will need to be 91% fuel. This is assuming a rather generous 290 second and 420 second specific average impulse, and that about 20% of total velocity is lost to drag during initial ascent.In otherwords a rocket like the Atlas V or the Delta IV's first stage wouldn't even reach orbit with ZERO payload -- they'll reach only about 6000 m/s, well short of the 7800 m/s require for LEO. The fact of the matter is that the only way to get a 91% fuel fraction rocket is to use a balloon tank and we don't know how to build a 97% fuel fraction vehicle, period!So, an SSTO vehicle will be very expensive and fragile and will need to be the size of an ICBM to the size of a baseball bat to lift a peanut into orbit. And, we are not even talking about reusability and carrying thermal protection and aerodynamic shaping for re-entry. Add those things on and you are asking for an engineering impossibility -- something akin to creating a fighting vehicle with armor plates that weigh less than stryofoam but is harder and stronger than steel. Posted by dwightlooi</DIV>  Read this article:X-33/VentureStar - What really happened. http://www.nasaspaceflight.com/content/?id=4180 The VentureStar was close to being successful except for the relatively trivial problem of finding lightweight hydrogen tanks. A material such as diamond with the same strength as the materials used now but at only 1/100th the weight would be well within the requirements for producing such a lightweight tank. My point is that the recent research suggesting of the capability to produce diamond to arbitrary size makes it possible that diamond can be used for structural parts in spacecraft:Artificial diamonds - now available in extra large. 18:11 13 November 2008 by Catherine Brahic. "Threat to commerce. "The team's method 'could be routinely run in any laboratory where it is needed,' says Alexandre Zaitsev, a physicist at the City University of New York, whose work also includes diamonds. 'When considered in combination with the high-growth-rate technique of CVD diamonds, it seems to be a starting point of mass-scale production of perfect diamond material at a low price.'" "Zaitsev considers low-pressure annealing at temperatures greater than 2000 °C to be a "breakthrough in diamond research and technology". "The improving quality of synthetic diamonds threatens the natural diamond market. While 20 tonnes of natural diamonds are mined annually, some 600 tonnes of synthetic diamonds are produced each year for industrial use alone." http://www.newscientist.com/article/dn16036  Your calculation is correct that it takes about 10 times as much fuel as the mass of the vehicle and payload you want to reach orbit. But imagine for example that the space shuttle orbiter instead of weighing 100 tons, only weighed 1 ton, with 3 main engines that had the same total thrust of 1.2 million pounds. This would be well within the capability to reach orbit with a fuel load that only needed to be 10 tons.    Bob Clark   <div class="Discussion_UserSignature"> </div>

dwightlooi · Jan 5, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'> Read this article:X-33/VentureStar - What really happened. http://www.nasaspaceflight.com/content/?id=4180The VentureStar was close to being successful except for the relatively trivial problem of finding lightweight hydrogen tanks. A material such as diamond with the same strength as the materials used now but at only 1/100th the weight would be well within the requirements for producing such a lightweight tank. My point is that the recent research suggesting of the capability to produce diamond to arbitrary size makes it possible that diamond can be used for structural parts in spacecraft:Artificial diamonds - now available in extra large. 18:11 13 November 2008 by Catherine Brahic. "Threat to commerce. "The team's method 'could be routinely run in any laboratory where it is needed,' says Alexandre Zaitsev, a physicist at the City University of New York, whose work also includes diamonds. 'When considered in combination with the high-growth-rate technique of CVD diamonds, it seems to be a starting point of mass-scale production of perfect diamond material at a low price.'" "Zaitsev considers low-pressure annealing at temperatures greater than 2000 °C to be a "breakthrough in diamond research and technology". "The improving quality of synthetic diamonds threatens the natural diamond market. While 20 tonnes of natural diamonds are mined annually, some 600 tonnes of synthetic diamonds are produced each year for industrial use alone." http://www.newscientist.com/article/dn16036  Your calculation is correct that it takes about 10 times as much fuel as the mass of the vehicle and payload you want to reach orbit. But imagine for example that the space shuttle orbiter instead of weighing 100 tons, only weighed 1 ton, with 3 main engines that had the same total thrust of 1.2 million pounds. This would be well within the capability to reach orbit with a fuel load that only needed to be 10 tons.    Bob Clark   Posted by exoscientist</DIV>Material strength is not the only problem. The material also has to be tough and easy to work with. You cannot weld, glue or rivet diamond for instance. Let's put it this way. An isogrid tank like the Delta IV tank can achieve about 85% fuel fraction. Not good enough. A balloon tank is capable of achieving 90~93% barely good enough. In fact, one of the first rockets to make orbit is very close to being SSTO. The original Atlas (not the Mk.V Atlas) uses a balloon tank with about 93% fuel fraction at launch. That is actually just shy of being enough for SSTO with RP-1/LOX, so they drop two of the three engines mid-flight.The real question with SSTO is why bother to make a very exotically constructed and very fragile vehicle to lift a very small payload into orbit just avoid the 2nd stage when the 2nd stage is not particularly expensive. The flaw with the Venturestar/X-33 ideal is not that SSTO is not possible. We know that it is. The problem is that even at the very limit of today's technology SSTO is not cheap, not robust and not efficient at lifting heavy payloads. Venturestar wants to add to that a rigid structure, flyable aeroshell, reusable engines, landing gears and metallic thermal protection. None of these are light and it will take a chain of Nobel worthy scientific break throughs to make them so. The end result was that we have the X-33 which didn't have the re-entry protection or even the fuel fraction to reach orbit, and even this has to resort to extreme lightening efforts such as the composite LH2 tanks which cracked. I don't believe that an orbital Venturestarthe technically feasible or that it'll be cheap. Remember, reusability doesn't = cheap. The Shuttle is resuable but also the most expensive way to get anything into orbit. Someting you can weld together at a muffler shop and using used washing machine parts will be cheap regardless of how many stages it has or if everything is one use.The SpaceX Falcon 1 has the right idea. One simple pressure fed upper stage. One simple pintle injection gas generator cycle 1st stage. No cryogenic fuels. All made and assembled using commonly available materials, tools and processes. It's the "washing machine" rocket. And, yes, it is cheap.

nec208 · Jan 8, 2009

The X-33 was not a SSTO it was shuttle on top of a rocket and lands like a plane. And stop talking about material and mass and address my points. <div class="Discussion_UserSignature"> </div>

MarkStanaway · Jan 8, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>The original Atlas (not the Mk.V Atlas) uses a balloon tank with about 93% fuel fraction at launch. That is actually just shy of being enough for SSTO with RP-1/LOX, so they drop two of the three engines mid-flight. Posted by dwightlooi</DIV>I seem to recall they orbited an entire Atlas booster back about 1960. Now that's pretty close to SSTO.Mark <div class="Discussion_UserSignature"> </div>

annodomini2 · Jan 8, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>The X-33 was not a SSTO it was shuttle on top of a rocket and lands like a plane. And stop talking about material and mass and address my points. Posted by nec208</DIV> The X-33 was a sub orbital technology demonstrator and was a single stage. <div class="Discussion_UserSignature"> </div>

dwightlooi · Jan 8, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>The X-33 was not a SSTO it was shuttle on top of a rocket and lands like a plane. And stop talking about material and mass and address my points. Posted by nec208</DIV>The X-33 has no chance of making orbit. And even then, it has to resort to exterme lightening to fly and land like a plane carrying its empty aeroshell and linear aerospike motor back. It was not on top of a rocket. It was the rocket. <img src="http://sitelife.space.com/ver1.0/Content/images/store/5/1/d5a3ff74-8e58-4cfe-a1b7-4f993f411d7b.Medium.jpg" alt="" />

dwightlooi · Jan 8, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>I seem to recall they orbited an entire Atlas booster back about 1960. Now that's pretty close to SSTO.Mark Posted by MarkStanaway</DIV> The Atlas is best described as 1.5 stage to orbit. Given that the paper thin, pressure supported balloon tanks weigh very little, a lot of its lift empty weight is in the engines. It drops two out of three of these during the ascent as the vehicle lightens and no longer require the thrust of all three engines.

exoscientist · Jan 9, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>The Atlas is best described as 1.5 stage to orbit. Given that the paper thin, pressure supported balloon tanks weigh very little, a lot of its lift empty weight is in the engines. It drops two out of three of these during the ascent as the vehicle lightens and no longer require the thrust of all three engines. Posted by dwightlooi</DIV>  I hadn't heard of the balloon tanks before. But this suggests possibilities for what could be achieved with materials with even better strength to weight ratios than steel,  such as diamond, which is better by a factor of 100.   Bob Clark  <div class="Discussion_UserSignature"> </div>

nec208 · Jan 21, 2009

Wow are you saying a rocket egine today is no more powerful than a rocket egine 20 year ago or more?And in the future the rocket egine will not be more powerful ? I know car egine are more powerful and you get more miles per gas than in old days.I would think 100 years of rocket egine is not long . <div class="Discussion_UserSignature"> </div>

webtaz99 · Jan 21, 2009

Rockets have always required the maximum performance, and the users (government mostly) were willing to pay to get it.  Cars are a bit different. <div class="Discussion_UserSignature"> </div>

nec208 · Jan 21, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Rockets have always required the maximum performance, and the users (government mostly) were willing to pay to get it.  Cars are a bit different. Posted by webtaz99</DIV>I was talking about advance engines where you get more power.But in the 100 years of rocket egines and if a rocket egine of 2009 is no more powerful than 1912 rocket egine than really rocket egines will not be more powerful  . The only reason cars and planes can go fast and more fuel efficient is advance engines over the years.And more money and research is being done to make cars and planes more powerful and fuel efficient . Well hybrid cars and electric cars are not that powerful and fuel efficient than cars that run on gas.But every year hybrid cars and electric cars are getting more powerful and fuel efficient .Now I don't know about rocket egines if they will get more powerful and fuel efficient .Has I know very little about rocket egines .    <div class="Discussion_UserSignature"> </div>

webtaz99 · Jan 22, 2009

The existing rocket engines are in the neighborhood of 95-98% of their theoretical maximums. That is why things like VASIMIR, ion engines and nuclear thermal are being investigated. <div class="Discussion_UserSignature"> </div>

nec208 · Jan 22, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>The existing rocket engines are in the neighborhood of 95-98% of their theoretical maximums. That is why things like VASIMIR, ion engines and nuclear thermal are being investigated. Posted by webtaz99</DIV>Can you explain this better has I know very little about rocket engines . <div class="Discussion_UserSignature"> </div>

annodomini2 · Jan 23, 2009

Basically, Rocket motors conceptually are very simple, mix fuel and oxidiser, ignite and route exhaust through nozzle. The main things that affect the 'power' of a rocket motor are:<ul><li> The fuel and oxidiser used</li><li>Shape of the nozzle</li></ul>Most of the development work performed on rocket motors has been for 3 things:<ul><li>Reduce weight</li><li>Increased Reliability</li><li>Reusability</li></ul>In comparison to car engines, a car engine has more moving parts and typically not very efficient. This is why improvements are not being made as rapidly as with car engines. Also a car engine is much cheaper to build than a large rocket motor. The main thing to look at with rocket motors is something called ISP (Specific Impulse), read up on this as there is too much to post here (there are many websites describing this).There is work being performed into newer nozzle designs such as aerospike nozzles (current ones are called bell nozzles), which may improve the thrust efficiency of the engine for a varying altitude. I suggest taking a look at some rocket science websites. Ion engines/VASMIR are new concepts in propulsion systems and use electricity to push plasma out the back of the motor electrically at very high speeds. They are typically lower thrust than chemical rockets, but use much less fuel. Currently they are only suitable for space based travel not orbital travel Nuclear thermal is basically a rocket motor to heat material (probably water) causing pressure and expansion (like a bottle rocket) which is again thrust out a nozzle, without the need for a chemical reaction. <div class="Discussion_UserSignature"> </div>

nec208 · Jan 23, 2009

Well yes rocket engines like plane engines have almost no moving parts.Mostly tubes  ,valves  and nozzles . Like http://www.enginehistory.org/G&jJBrossett/JPSAir&SpacePark/J-2%20Rocket%20engine.JPGhttp://www.nationalmuseum.af.mil/shared/media/photodb/photos/050328-F-1234P-010.jpg http://www.daviddarling.info/images/F-1_rocket_engine.jpgBut there is some thing I'm not understanding .Why is plane engines getting more powerful and fuel efficient but not rocket engines?Like every year plane engines are getting more powerful and fuel efficient and we may be at mock 7 in 10 years from now!!!Can advance electronics help?    <div class="Discussion_UserSignature"> </div>

marko_doda · Jan 24, 2009

Plane engines are getting more & more powerful & fuell efficient because most of their reactans mass is air, you suck air, compress it, burn it and you have trust. You can suck more air for more thrust or you can suck the same air in less space to save fuel. Also now there are plans to switch the jet fuel to hydrogen (used in the first jet engine), which is lighter, cleaner & has higher Isp, but storing  the liquid hydrogen is complex and not effective for jets Rocket engines carry everything onboard, so you don't have an unlimited reactans mass, so only way to increase performance is to compress the fuel to high pressure (like the N1 engines) and use effective nozzles or aerospike. Rocket engines using hydrogen are more efficient, however the tanks & pipes for liquid hydrogen are expensive so the whole rocket is more expensive than a RP1 rocket.If in the near future storing of liquid hydrogen is improved it would be really cool, we will have greener, faster jets, and cheaper rockets.

Delta Clipper and DC-X /DC-XA.

nec208

Guest

exoscientist

Guest

nec208

Guest

exoscientist

Guest

nec208

Guest

exoscientist

Guest

nec208

Guest

dwightlooi

Guest

nec208

Guest

exoscientist

Guest

dwightlooi

Guest

nec208

Guest

MarkStanaway

Guest

annodomini2

Guest

dwightlooi

Guest

dwightlooi

Guest

exoscientist

Guest

nec208

Guest

webtaz99

Guest

nec208

Guest

webtaz99

Guest

nec208

Guest

annodomini2

Guest

nec208

Guest

marko_doda

Guest

Similar threads

TRENDING THREADS

Latest posts

Share this page