DC-X Delta Clipper

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I guess it is time to discuss this in detail as The blue origin new shephard is based on this
http://youtube.com/watch?v=Hm0tR96lAgw

also
http://media.armadilloaerospace.com/DCX/
 
Hi,

http://www.flightglobal.com/pdfarchive/view/1995/1995%20-%201428.html
 

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Pete Conrad had a great program going in the DC-X. Unfortunately NASA and/or the DOD didn't follow on with it. Not sure about Blue "O" it seems they hired some MCD engineers from the DC-X program. Had an interesting test flight a couple years ago....then nothing since? I was at white sands back then and saw the DC-X fly from a distance a truly awe inspiring sight. :'(
 
airrocket said:
Pete Conrad had a great program going in the DC-X. Unfortunately NASA and/or the DOD didn't follow on with it. Not sure about Blue "O" it seems they hired some MCD engineers from the DC-X program. Had an interesting test flight a couple years ago....then nothing since? I was at white sands back then and saw the DC-X fly from http://en.wikipedia.org/wiki/DC-XA
McDonnell Douglas DC-X - Wikipedia, the free encyclopediaa distance a truly awe inspiring sight. :'(

A full-scale pre-production prototype was planned, the orbital DC-Y, followed by the production DC-1. However, in the project had originally started as part of the SDI, and so was not in favor with the Administration that had come to power, and funds were cut.

NASA took over the program (although there are strong indications it really didn't want to-- Not Invented Here) and updated a good deal of the technology in its construction, re designating it DC-XA. This was renamed Clipper Graham to honor Lt. General Daniel O. Graham, who championed the concept. Flight testing resumed in 1996. However, on the fourth flight, the first NASA controlled flight a NASA team failed to connect the hydraulic lines to one of the landing gear, and after a successful flight one of the landing legs failed to extend. It made a soft landing, but then fell over on its side. While the damage was not catastrophic, leaking LOX ignited and destroyed the vehicle.

NASA chose not to rebuild. They seemed to prefer bigger and often riskier programs, plus DC-X suffered from the Not Invented Here. They decided to use the funding to start the vastly more complex (and in my mind much less sensible) X-33 program which might someday have lead to an operational vehicle called VentureStar. Of course all of that came to nought
 
Here's a pic of the production, full size DC-Y:
 

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I think NASA’s greatest problem with DC-X and DC-Y was that McD wanted to revolutionise space travel by producing the first non-experimental, certified space vehicle. That way any competent agency or enterprise could purchase space vehicles for their use returning NASA to the business of wind tunnel modelling…

As a recent participant to the Australian government’s future conference I tried to raise some interest in DC-X. Limited to 500 words here was my written proposal.

Cheap, Easy Access to Space

By Abraham Gubler for the Australia 2020 Forum

By the year 2020 humans will have been travelling or sending controlled objects into space for 60 years yet space remains heavily underutilised compared to air travel 60 years after the Wright Brother achieved first flight. While the Earth’s full gravity well and the harshness of the space environment remain significant impediments to space they are not the cause of this underutilisation.

Despite 60 years of space travel the vehicles required for commercial access to space remain strictly controlled by state space and/or experimental agencies. This is the equivalent of imagining that in the 1960s all commercial and private air travel within Australia could only be conducted by the Civil Aviation Safety Authority (CASA). However air travel is widespread through the simple process of safety certification, where an aircraft is designed, built and proven to operate within certain parameters and if maintained and operated by appropriately skilled personnel will be completely safe in its use.

However space vehicles remain classed as experimental and effectively useable only once. Even the supposedly reusable Space Shuttle requires some $500 million of maintenance between each flight which effectively involved rebuilding the system. This is like spending $100-200 million to rebuild each QANTAS 747 after it completes a single flight from Sydney to London.

However spacecraft can be designed and built to achieve the same certification standards as commercial and private aircraft. McDonnell Douglas (now part of the Boeing Company) built and tested a single state to orbit (SSTO), reusable launch vehicle (RLV) rocket called the Delta-Clipper X (DC-X) in the 1960s. The DC-X was designed to achieve a civil aviation certification be cheap to build (it used off the shelf components), safely land if one of its engines failed, require very low maintenance between flights and could even be stored in the open for extended periods between use. The sub-scale prototype was built and successfully tested for only US$60 million and by using the DC-X concept the cost of orbiting payloads would be 1/10th of current spacecraft.

Despite this highly impressive performance the DC-X program was abandoned because of the bureaucratic and political will of the US Government. DC-X was originally funded by the US Air Force as part of research into the second generation ballistic missile defence (BMD) system ‘Star Wars’ and with a change of US Government in 1992 lost its funding. The US space agency NASA briefly funded more successful trials but cancelled the program to concentrate on far less efficient spacecraft that were not designed for civil certification.

The DC-X spacecraft could be resurrected by the Australian government and industry in cooperation with the USA if a relatively small amount of funds was made available. Funding required would be in the realm of one to ten billion but would be far less than the potential earnings and efficiency savings. By proving the concept of the certified space craft and building them in Australia not only would cheap and easy space access be made available but Australian industry would benefit from the massive global demand. Much of the risk reduction work has been done it just requires visionary investment.
 
Abraham Gubler said:
I think NASA’s greatest problem with DC-X and DC-Y was that McD wanted to revolutionise space travel by producing the first non-experimental, certified space vehicle. That way any competent agency or enterprise could purchase space vehicles for their use returning NASA to the business of wind tunnel modelling…

As a recent participant to the Australian government’s future conference I tried to raise some interest in DC-X. Limited to 500 words here was my written proposal.

Cheap, Easy Access to Space

By Abraham Gubler for the Australia 2020 Forum

[snip]

Despite this highly impressive performance the DC-X program was abandoned because of the bureaucratic and political will of the US Government. DC-X was originally funded by the US Air Force as part of research into the second generation ballistic missile defence (BMD) system ‘Star Wars’ and with a change of US Government in 1992 lost its funding. The US space agency NASA briefly funded more successful trials but cancelled the program to concentrate on far less efficient spacecraft that were not designed for civil certification.

The DC-X spacecraft could be resurrected by the Australian government and industry in cooperation with the USA if a relatively small amount of funds was made available. Funding required would be in the realm of one to ten billion but would be far less than the potential earnings and efficiency savings. By proving the concept of the certified space craft and building them in Australia not only would cheap and easy space access be made available but Australian industry would benefit from the massive global demand. Much of the risk reduction work has been done it just requires visionary investment.

While I would agree totally with your overall philosophy, especially your conclusions, I don't think civil certification entered into it that much. In those days, no one even had any idea on how to civilly certify a spacecraft. For that matter, they still don't. At least for the first few years of Virgin Galactic's operations, people on board will be classified as "participants" in an experimental program, thereby avoiding some of the certification issues, as well as keeping the trial lawyers at bay (without some way to accomplish the latter, there never will be manned US civil space operations).

DC-X/Y/1 were intended specifically to meet the requirements of reliable, repeatable and affordable access to space in order to service the planned space based missile defense system. Such a spacecraft has obvious civilian benefits, but that was secondary and would just be a fortuitous byproduct. Supporting SDI/BMD was its reason for existence. It was also the SDI program, not USAF, that funded it. Its associate with SDI was why the Clinton Administration killed it.

NASA took it up only reluctantly, primarily because it generated so much favorable publicity and under congressional pressure, but was never a supporter. It wasn't invented there, and it was also perceived as a threat to the Shuttle. As we know, they threw it under the bus as soon as they could in favor of their own technology, linear aerospike. This would have resulted in the rather strange X-33, which was hoped would lead to the Lockheed VentureStar, which was planned to have civil as well as military operations. Whether NASA would support any private companies to operate it was another thing, but that issue would have arisen with DC-1 as well.

Of course, the concept went nowhere, but it illustrates a recurring complaint that has been raised about NASA over the years: If you need a spaceship to smuggle a few things or people around the galaxy, you'd hope someone would offer you something like the Millennium Falcon. NASA would want to build you the Death Star.

I am posting here a picture of the conversation that resulted in the birth of the DC-X. Pictured from left to right are Vice President Dan Quayle, then head of the National Space Council, Army Lt. Gen. Daniel O. Graham, for whom DC-XA would later be named, the prominent American aerospace engineer Max Hunter, and the noted science fiction author, space and science writer and journalist Jerry Pournelle. Based on the discussions that took place at this meeting, Vice President Quayle arranged for SDI funding for DC-X and beyond
 

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Abraham Gubler said:
Thanks for the good insight F-14D.

If you'd like to see what I'm talking about when I talk about "Millenium Falcon vs. Death Star", look up how NASA's 1980s-early 1990s plans for going to Mars. Then compare them with Dr. Zubrin's "Mars Direct" concept. Originally violently opposed by NASA, when it gained popularity and looked like it had a chance of being funded (because it was much cheaper), was embraced by NASA and grown somewhat into the still very achievable and cost effective "Mars Reference Mission". However, as soon as President Bush, announced the return to the Moon and eventually on to Mars concept for NASA to achieve, NASA abandoned the Reference Mission and went back to their beloved concept of massive fleets of rockets and enormous infrastructure.

The Empire Strikes Back!

I wish you every success in convincing your government to accomplish what we were too stupid to do.
 
F-14D said:
If you'd like to see what I'm talking about when I talk about "Millenium Falcon vs. Death Star", look up how NASA's 1980s-early 1990s plans for going to Mars. Then compare them with Dr. Zubrin's "Mars Direct" concept.

I think you mean "Martin Mariettas Mars Direct concept." Zubrin did not originate it. He was *at* *best* just one member of dozen-plus team. He was, however, the one most capable of self-promotion...

However, as soon as President Bush, announced the return to the Moon and eventually on to Mars concept for NASA to achieve, NASA abandoned the Reference Mission and went back to their beloved concept of massive fleets of rockets and enormous infrastructure.

NASA has virtually no Mars plans whatsoever, nevermind "massive fleets of rockets."
 
Orionblamblam said:
F-14D said:
If you'd like to see what I'm talking about when I talk about "Millenium Falcon vs. Death Star", look up how NASA's 1980s-early 1990s plans for going to Mars. Then compare them with Dr. Zubrin's "Mars Direct" concept.

I think you mean "Martin Mariettas Mars Direct concept." Zubrin did not originate it. He was *at* *best* just one member of dozen-plus team. He was, however, the one most capable of self-promotion...

However, as soon as President Bush, announced the return to the Moon and eventually on to Mars concept for NASA to achieve, NASA abandoned the Reference Mission and went back to their beloved concept of massive fleets of rockets and enormous infrastructure.

NASA has virtually no Mars plans whatsoever, nevermind "massive fleets of rockets."


Although he was employed by, and supported by Martin Marietta, I believe the "Mars Direct" concept came from Zubrin. It made great sense, and MM backed him to the full. Self-promotion, frankly, is something the space program really needs, more that worrying about which percentage should be credited to who. Zubrin's (or Martin's, if you will) concept would work, and more importantly wouldn't take decades. Given politicians that can't see beyond the next election and corporate CEOs that can't see beyond the next quarterly report, if it takes decades, it ain't gonna happen.

Regarding the "fleets", ever since Pres. Bush's pronouncements, Mars has always been part of the "vision". NASA has continually briefed on how Lunar exploration will also be used as a stepping stone and logistical support base to go to Mars (something a number of people say is unnecessary, I don't know; could be rival camps). Quoting from a Dec., 2006 briefing, "We have the large launch vehicle Aries V that can launch enough mass to support sending the lander that Doug described to the Moon, to be able to put enough infrastructure there and then to eventually get us on to Mars". Now given that they consider building the lunar base necessary to go to Mars, and to send astronauts to the moon they plan to use two rockets for each mission (40 years ago we did it with one), that sounds like the beginnings of a fleet.

I'm totally in favor of human lunar exploration for its own sake. But given the capabilities of the Ares system, when you start extrapolating this to eventual (admittedly at this point ill-defined) Mars missions, I'm terribly afraid that we're seeing the first frames being constructed for the Death Star.
 
Nice story in the last Boeing Frontiers
http://www.boeing.com/news/frontiers/i_history.pdf
 

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F-14D said:
Although he was employed by, and supported by Martin Marietta, I believe the "Mars Direct" concept came from Zubrin.

David Baker and about a dozen others might have somethign different to say about that.

Self-promotion, frankly, is something the space program really needs...


No, it does not. Promotion of plans and technologies... sure. promotion of *people,* not so much. Do that and you wind up with the clusterfuck that is the "Mars Society:" a wonderful concept that has become one man's personal kingdom and led to many of the best and most enthusiastic to throw up their hands in disgust and walk away.


Regarding the "fleets", ever since Pres. Bush's pronouncements, Mars has always been part of the "vision".

Not in any real sense. MArs has been a vague, handwavy notional target for *after* the moon, with just about all development focussed on the Moon with very little effort devoted to Mars.

NASA has continually briefed on how Lunar exploration will also be used as a stepping stone and logistical support base to go to Mars (something a number of people say is unnecessary, I don't know; could be rival camps).

The primary utility of Lunar exploration as a stepping stone for Mars would be in building up the requsite launch infrastructure on *Earth.*
 
Orionblamblam said:
F-14D said:
Although he was employed by, and supported by Martin Marietta, I believe the "Mars Direct" concept came from Zubrin.

David Baker and about a dozen others might have somethign different to say about that.

Self-promotion, frankly, is something the space program really needs...


No, it does not. Promotion of plans and technologies... sure. promotion of *people,* not so much. Do that and you wind up with the clusterfuck that is the "Mars Society:" a wonderful concept that has become one man's personal kingdom and led to many of the best and most enthusiastic to throw up their hands in disgust and walk away.


Regarding the "fleets", ever since Pres. Bush's pronouncements, Mars has always been part of the "vision".

Not in any real sense. MArs has been a vague, handwavy notional target for *after* the moon, with just about all development focussed on the Moon with very little effort devoted to Mars.

NASA has continually briefed on how Lunar exploration will also be used as a stepping stone and logistical support base to go to Mars (something a number of people say is unnecessary, I don't know; could be rival camps).

The primary utility of Lunar exploration as a stepping stone for Mars would be in building up the requsite launch infrastructure on *Earth.*


The point I'm making is that whether Zubrin was the instigator or just the loudest promoter, he was the one that got manned Mars missions back on the radar. If you look at the concepts NASA was promoting before Zubrin et.al., You saw hundreds of billions $ programs that were basically building the Death Star and were dead on arrival. He loudly pushed a concept that made the initial missions affordable. He (and whoever else you want to credit) realized that no one was going to pay for the development of really efficient technologies to routinely go to Mars until we saw that we could get to Mars. The Mars Design Reference Mission was doable with existing or near-term technologies.

The space program needs to be sold to the general public who believes we've already been extensively in space ever since Capt. Kirk first said "Warp factor one". Engineering studies traded among experts aren't going to get the necessary funding out of Governments, not when there's a chance to spread pork amongst the voters in the short term building bridges to nowhere. That is what was the value of Zubrin's [self, if you will] promotion: He was showing a way to get to Mars in a politically realistic time. Something that takes 25-30 years simply isn't going to survive, the originators will all be gone and politicians don't think beyond the next couple of elections. One of the advantages of the Apollo program was that the goal was set so that it would be achieved while most of the politicians who were in office at the start expected to still be there when the goal was achieved.

A problem with the Ares/Orion concepts is that the public sees a pointy capsule that splashes down in the water and says, "Didn't we already do that"? As far as exploration of the Moon (something I favor) goes, they say, "Didn't we already completely do that"? There's not much enthusiasm, especially when it's noted that the original new concepts are based on derivatives of 1970s equipment, some of which has been repaced by derivatives of 1960s equipment. Getting past that is the big benefit of Mars Direct of the Design Reference Mission. It's salable, and the fallout of that will also allow us to do the Moon. DC-X would have been the same. Small, practical support infrastructure and significantly reusable.

The argument against the Moon being a stepping stone to Mars, as I understand it is that while going to the Moon may be worthwhile for its own sake, you don't need to go there to go to Mars, The infrastructure on Earth can be built here to go to Mars directly, and would also be available for lunar missions as fallout, but you don't need the Moon as a prerequisite. Also, by building for Mars, the costs of gong to the Moon don't get roilled in as part of the cots of going to Mars, which will happen if you call the Moon a "stepping stone".


Bringing it back to the point of this thread, DC-X was a fantastic concept that died due to hostility of one political entity and hostility from a bureaucracy that resented it because it was Not Invented Here. We need something like DC-X if we're ever going to go routinely to space.
 
F-14D said:
The point I'm making is that whether Zubrin was the instigator or just the loudest promoter, he was the one that got manned Mars missions back on the radar.

By focussing on one man - as is often done WRT Mars Direct - problems with the concept (and there were many) tend to get washed away by the cult of personality. Simultaneously, by focusing on one man, that one man's views cen get blown out of proportion; when the rest of the team is ignored, success or failure can often rely on just that one man. And when that one man is someone like Zubrin, who is a master of thrilling the crowds and also of driving away the technical, political and financial experts, the project is doomed.

He loudly pushed a concept that made the initial missions affordable.


So he said, yes. And then people started workign on the details...


A problem with the Ares/Orion concepts is that the public sees a pointy capsule that splashes down in the water and says, "Didn't we already do that"? As far as exploration of the Moon (something I favor) goes, they say, "Didn't we already completely do that"?

There's the small problem that the physics argues in favor of "we've already done that" designs.


The argument against the Moon being a stepping stone to Mars, as I understand it is that while going to the Moon may be worthwhile for its own sake, you don't need to go there to go to Mars,

You can't go to Mars using Atlas Vs and Delta IVs. You need Big Ass Boosters. However, since Shuttle is going away, any Big Ass Booster would ahve to be an all new thing. And the chances of building such a booster specifically for manned Mars is minimal at best. While on the other hand, lunar development is a *lot* easier and *far* more profitable. There is *no* chance of profit from manned Mars anytime soon. From the moon? You betcha.

So until such time as a launch vehicle capable of supporting manned Mars comes about... you *do* need the Moon.

The infrastructure on Earth can be built here to go to Mars directly...


Hell, why waste your time with Mars? The infrastucture for a manned mission to Saturn can be built here on Earth. Mars missions can be fallout.
 
Orionblamblam said:
F-14D said:
The point I'm making is that whether Zubrin was the instigator or just the loudest promoter, he was the one that got manned Mars missions back on the radar.

By focussing on one man - as is often done WRT Mars Direct - problems with the concept (and there were many) tend to get washed away by the cult of personality. Simultaneously, by focusing on one man, that one man's views cen get blown out of proportion; when the rest of the team is ignored, success or failure can often rely on just that one man. And when that one man is someone like Zubrin, who is a master of thrilling the crowds and also of driving away the technical, political and financial experts, the project is doomed.

He loudly pushed a concept that made the initial missions affordable.


So he said, yes. And then people started workign on the details...


A problem with the Ares/Orion concepts is that the public sees a pointy capsule that splashes down in the water and says, "Didn't we already do that"? As far as exploration of the Moon (something I favor) goes, they say, "Didn't we already completely do that"?

There's the small problem that the physics argues in favor of "we've already done that" designs.


The argument against the Moon being a stepping stone to Mars, as I understand it is that while going to the Moon may be worthwhile for its own sake, you don't need to go there to go to Mars,

You can't go to Mars using Atlas Vs and Delta IVs. You need Big Ass Boosters. However, since Shuttle is going away, any Big Ass Booster would ahve to be an all new thing. And the chances of building such a booster specifically for manned Mars is minimal at best. While on the other hand, lunar development is a *lot* easier and *far* more profitable. There is *no* chance of profit from manned Mars anytime soon. From the moon? You betcha.

So until such time as a launch vehicle capable of supporting manned Mars comes about... you *do* need the Moon.

The infrastructure on Earth can be built here to go to Mars directly...


Hell, why waste your time with Mars? The infrastucture for a manned mission to Saturn can be built here on Earth. Mars missions can be fallout.

This is becoming a controversy about personalities and engineering. However, what is really the issue is going to be the public's perceptions and political willingness, which historically doesn't last for a long time since the Age of Empires passed. I'll repeat my contention. Zubrin got regular people somewhat excited about space again. Mars Direct had a number of flaws, yes, including the fact that while it had a solution to provide low-g for the astronauts on the way to Mars, it didn't really have a solution on how to provide that on the return. A lot of the issues were addressed in the Design Reference Mission.

Regarding, "We've already done that", while the engineering could arguably favor that, it doesn't take into account the larger issues regarding the environment in which this all has to happen. Specifically, convincing the citizenry to pay for it. I am reminded of some engineers' violently objecting to the DC-X (See? Bringing it back on topic) concept because of the large fuel fraction relative to the deliverable payload. This was correct, but overlooked an important fact--fuel is cheap. What kills you is the vehicle costs, infrastructure and cost to operate. In those areas, DC-X just beat the throw-away multi-stage rocket all to heck.


It's true that we need to "Big Ass Boosters" to go to Mars. Well actually, we need a way to get a decent amount of material into LEO. This can be through B.A.B.s or though the ability to routinely get a smaller payload up there (DC-X). Once in LEO most of the heavy lifting is done whether you are going to the Moon or Mars. Problem is we aren't going to do it with a concept that requires twice as many throwaway rockets for each mission as what we used 40 years ago. Take a look at the Design Reference Mission. Like Mars Direct, it assumed that there would be some (Shuttle technology derived?) repeatable way to economically get decent weight to LEO. The thing about Mars Direct/Design Reference was that once you got to LEO it drastically reduced the throw-weight required to go from LEO to Mars.

We aren't going to make a profit on the moon without something other than the presently planned concept for getting there. We can't have the big Mission Control scenario. The point, though is that we don't need to go to the Moon as a stepping stone to Mars. There may be a lot of good stuff there, and I believe there is, but we don't need to go there to go to Mars. What we do need is an economical way to LEO (same for the Moon) and a vehicle capable of the kind of duration of a Mars mission. Going to the Moon won't get us that. Again, going to the Moon is no doubt worthwhile in its own right, but it isn't necessary to get to Mars or beyond.


With all the (to me) unnecessary controversy that seems to have developed here, keep in mind why I brought up Mars Direct in the first place. It wasn't to start singing the praises of a Mars mission vs. lunar return or to sell Zubrin T-shirts. It was to illustrate the philosophy underlying why NASA was not a strong supporter of DC-X/Y/1. Like Zubrin's (or whoever's) vision of going to Mars; it could get the job done with the Millenium Falcon and NASA wants to build the Death Star.
 
F-14D said:
Regarding, "We've already done that", while the engineering could arguably favor that, it doesn't take into account the larger issues regarding the environment in which this all has to happen. Specifically, convincing the citizenry to pay for it.


Honestly, the citizenry don't need to be convinced of jack shit on this. The bulk of the citizenry are opposed to the bulk of US Federal spending, yet it still happens. Those who need convincing are Congress and the President. And convincing them of going straight from Nothign to Mars just ain't gonna fly. The Moon is realtively easy, and would make Mars a lot easier.

I am reminded of some engineers' violently objecting to the DC-X (See? Bringing it back on topic) concept because of the large fuel fraction relative to the deliverable payload. This was correct, but overlooked an important fact--fuel is cheap.

Wait... what? That arguement makes no sense. The issue with high propellant fraction vehicles is *not* fuel cost... it's building a vehicle like an eggshell that can reliably stand up to a wide range of rather horrible environments, from acceleration to vibration to pressure changes to aerothermal heating.


We aren't going to make a profit on the moon without something other than the presently planned concept for getting there.

Unclear. The resources from the moon that could make money - microwaves and potentially He3 - don;t need doodly squat in terms of return capability.

we don't need to go to the Moon as a stepping stone to Mars. ... What we do need is an economical way to LEO

Great. Using what? Feel free to develop your own launch vehicle. Alternatively, figure out how to use what's currently in development.

it could get the job done with the Millenium Falcon and NASA wants to build the Death Star.

I'm still waiting for evidence that NASA wants to build the Death Star, for Mars or any other mission.
 
Orionblamblam said:
F-14D said:
Regarding, "We've already done that", while the engineering could arguably favor that, it doesn't take into account the larger issues regarding the environment in which this all has to happen. Specifically, convincing the citizenry to pay for it.


Honestly, the citizenry don't need to be convinced of jack shit on this. The bulk of the citizenry are opposed to the bulk of US Federal spending, yet it still happens. Those who need convincing are Congress and the President. And convincing them of going straight from Nothign to Mars just ain't gonna fly. The Moon is realtively easy, and would make Mars a lot easier.

I am reminded of some engineers' violently objecting to the DC-X (See? Bringing it back on topic) concept because of the large fuel fraction relative to the deliverable payload. This was correct, but overlooked an important fact--fuel is cheap.

Wait... what? That arguement makes no sense. The issue with high propellant fraction vehicles is *not* fuel cost... it's building a vehicle like an eggshell that can reliably stand up to a wide range of rather horrible environments, from acceleration to vibration to pressure changes to aerothermal heating.


We aren't going to make a profit on the moon without something other than the presently planned concept for getting there.

Unclear. The resources from the moon that could make money - microwaves and potentially He3 - don;t need doodly squat in terms of return capability.

we don't need to go to the Moon as a stepping stone to Mars. ... What we do need is an economical way to LEO

Great. Using what? Feel free to develop your own launch vehicle. Alternatively, figure out how to use what's currently in development.

it could get the job done with the Millenium Falcon and NASA wants to build the Death Star.

I'm still waiting for evidence that NASA wants to build the Death Star, for Mars or any other mission.


This is getting to be too tense and personal. Let me try one more time, but this forum shouldn't be a debating society.

Space spending is an easy target. If the public isn't interested or think we're just repeating ourselves, they'll object to the money being spent on such "waste". The constituency for space is relatively small and fragile. We have to excite the general public.


Regarding the fuel fraction, the DC-X/Y/1 would use more propellant to get weights to LEO than throwaway one-shot rockets, and that's what some focused on, some quite loudly. Their objection was correct, but irrelevant because what DC-X was offering was much cheaper vehicle costs, through reuse, quick turnaround and not needing all the expensive facilities, Mission Control, etc. that we had been using.

Microwaves (from lunar distance?) and He3 won't be profitable unless we have a cheaper way to get there than what we're planning, and one would like to think that the astronauts that go there to build and run it would like to come back, on occasion.

Actually, I would like us to develop a more economical vehicle to LEO. I think we could call it---DC-X.


Famous Death stars:

The Space Shuttle ( a 1500 mile cross range capability on a vehicle that normally only lands at two places on Earth)

The ISS as it eventually was executed (a discussion for another time).

The plan to go to Mars prior to the adoption of a modified Mars Direct as the Design Reference Mission.

X-33 vs. DC-X

X-Wing
 
A question about the DC-1: I read somewhere (probably Encyclopedia Astronautica) that it was to do a nose-first re-entry. I presume this had the benefits of increasing cross-range (by improving the lift-to-drag ratio) and eliminating the need to protect the engines. But how was a nose-first entry to have been accomplished? It seems likely that the vehicle would have been fundamentally tail-heavy, since the engines would have been in the tail, so it would not have been naturally stable in a nose-first orientation. Would thrusters have been used to maintain orientation (I'd have thought they'd have to be quite powerful)? Aerodynamic surfaces? Or did the vehicle actually contrive to have its center of mass sufficiently far forward as to be stable in a nose-first attitude?
 
The ISS and the Shuttle are both "Death Stars". NASA lacks any sort of coherent vision and fortitude to stick with a good idea and carry it through. All they seem bent on carrying out Washington's pork barrel agenda.

Sadly, it's all the good ideas like the DC-X. X-33, and the OSP that seem to get consigned to history's dustbin .

Unfortunately, Project Constellation, like the Shuttle and the ISS, won't be going to the dustbin. No, the fat-cat politcians and their home states would be very unhappy to give up pork, especially when it's theirs.
 
XP67_Moonbat said:
The ISS and the Shuttle are both "Death Stars". NASA lacks any sort of coherent vision and fortitude to stick with a good idea and carry it through. All they seem bent on carrying out Washington's pork barrel agenda.

Sadly, it's all the good ideas like the DC-X. X-33, and the OSP that seem to get consigned to history's dustbin .

Unfortunately, Project Constellation, like the Shuttle and the ISS, won't be going to the dustbin. No, the fat-cat politcians and their home states would be very unhappy to give up pork, especially when it's theirs.

I completely agree with your position, although I might classify X-33 as one of the Death Stars. It was designed to do the same thing as DC-X/Y/1, but was a wildly complex way to do it requiring a risky, complex and giant leap in technology in one step that ultimately proved unsuccessful, so we ended up with nothing. One example of the complexity was how early flights were to be conducted. X-33 would launch from Edwards AFB and then fly to Dugway Proving Grounds in Utah. The X-33 couldn't be flown back and the plan was that it would have to be trucked all the way back. One issue was that the X-33 on a trailer would not be able to fit under some of the highway bridges en route, so NASA was going to have to pay to have those bridges rebuilt.



Luke Skywalker: Look at him. He's headed for that small moon.
Han Solo: I think I can get him before he gets there. He's almost in range.
Obi-Wan Kenobi: [with sudden realization] That's no moon. It's a space station.
Han Solo: It's too big to be a space station.
Luke Skywalker: I have a very bad feeling about this.
 
F-14D said:
If the public isn't interested or think we're just repeating ourselves, they'll object to the money being spent on such "waste".

So? Once again, the public doesn't get to vote on spending. If they did, the US Federal budget would be a buck-o-five.
 
Proponent said:
A question about the DC-1: I read somewhere (probably Encyclopedia Astronautica) that it was to do a nose-first re-entry. I presume this had the benefits of increasing cross-range (by improving the lift-to-drag ratio) and eliminating the need to protect the engines. But how was a nose-first entry to have been accomplished? It seems likely that the vehicle would have been fundamentally tail-heavy, since the engines would have been in the tail, so it would not have been naturally stable in a nose-first orientation. Would thrusters have been used to maintain orientation (I'd have thought they'd have to be quite powerful)? Aerodynamic surfaces? Or did the vehicle actually contrive to have its center of mass sufficiently far forward as to be stable in a nose-first attitude?


Because of military and polar orbit requirements and the safety issue of being able to land after one orbit, the orbital vehicle would reenter nose first and its shape would act as a lifting body to provide cross range capability (though not as much as the Shuttle was designed for, but never used) in conjunction with control surfaces. Approaching the landing site, it would flip and then descend on an impressive column of flame, as demonstrated by Flash Gordon decades ago.
 
F-14D said:
[T]he orbital vehicle would reenter nose first and its shape would act as a lifting body to provide cross range capability....

But how would the nose-first attitude have been maintained through re-entry? Aerodynamic surfaces? Forward CG? If forward CG, how was the CG kept or moved forward?

Approaching the landing site, it would flip and then descend on an impressive column of flame, as demonstrated by Flash Gordon decades ago.
;D ;D ;D
 
Proponent said:
F-14D said:
[T]he orbital vehicle would reenter nose first and its shape would act as a lifting body to provide cross range capability....

But how would the nose-first attitude have been maintained through re-entry? Aerodynamic surfaces? Forward CG? If forward CG, how was the CG kept or moved forward?

Not completely sure; it was described as aerodynamic lift in conjunction with large control surfaces (whatever that means). Basically, it would fly (well glide, actually). This had not yet been tested when DC-X/Y/1 was abandoned, and would have been a major focus of later tests and of the DC-Y vehicle as would be heat dissipation from the nose.
 
From Flug Revue
 

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The DC-X is often cited by NewSpace and/or SSTO advocates as a prime example of what could have been. I have no trouble believing that so much more could have been achieved if the large sums spent on the X-33 had instead been spent on DC-Y etc. However, I'm not convinced that achieving SSTO is quite as (relatively) straightforward as some advocates, such as the late Harry Stine, suggest.

So what are people's views on this forum about whether the DC-Y would have been at least a technical success? Are projects like Reaction Engines' Skylon making things unnecessarily complicated?

P.S. Not looking to start a flame war! Just looking, as ever, to learn more from others more knowledgable than me :)
 
FutureSpaceTourist said:
So what are people's views on this forum about whether the DC-Y would have been at least a technical success?

"Would have?" Impossibel to say. "Could have?" Certainly.

Are projects like Reaction Engines' Skylon making things unnecessarily complicated?

Yes. You only progress from "simple" to "complex" when "simple" is proven incapable of doing the job and you *have* to move to "complex." Starting with complex from Day One is a sure way to spend a whole lot of money and not get anywhere. In this case, liquid biprop rocket engines have proven to be perfectly capable of horsing a launch vehicle into orbit and being reusable, (relatively) inexpensive and lightweight.
 
FutureSpaceTourist said:
So what are people's views on this forum about whether the DC-Y would have been at least a technical success? Are projects like Reaction Engines' Skylon making things unnecessarily complicated?

What was revolutionary about the Delta Clipper (X and Y) is not the technology but the concept. Technically they were very conservative with engines and most components off the shelf. The concept was to package all of these proven components into a reusable structure able to achieve SSTO (and back) and to make this vehicle on a mass production assembly line with civil certification. So unlike most space launchers it would not be produced and managed like an experimental vehicle for a single use only. It would be certified to FAA standard and could be managed much like a commercial airliner with obvious differences in the operational nature. This is the key obstacle to making space launching a low cost and mass capability – treating the launcher as a low cost and mass system. Since it achieved all the milestones in the DC-X testing regime with flying colours there is no reason to assume that it couldn’t have progressed further.
 
F-14D said:
Not completely sure; it was described as aerodynamic lift in conjunction with large control surfaces (whatever that means). Basically, it would fly (well glide, actually). This had not yet been tested when DC-X/Y/1 was abandoned, and would have been a major focus of later tests and of the DC-Y vehicle as would be heat dissipation from the nose.

DC-X's shape was based on AMaRV with few changes. AMaRV was proven, and they were confident it could perform the required maneuver.
 
Thank you for the replies. The DC-X undoubtedly proved a number of things (eg practical reusability of a VTOL craft, that a lot can be achieved for relatively low amounts of money, that existing technology will go a long way etc) but that of course does not prove that the larger scale design would have the capability to reach orbit.

Abraham Gubler said:
Since it achieved all the milestones in the DC-X testing regime with flying colours there is no reason to assume that it couldn’t have progressed further.

I think this is the crux of the issue for me. In the absence of proof we're left with that the sub-scale DC-X achieved what it was set out to do, so there's no reason to doubt that the full scale wouldn't?

More concretely, the next few years should be very interesting as Blue Origin, Armadillo and Masten all (hopefully) proceed with fully reusable space-based, albeit suborbital, VTOL systems. May be then we'll have a real demonstration of what a missed opportunity the DC-X was!
 
I can't help but wonder what might have happened had they chose McDonnell Douglas's DC-X derived X-33 concept instead of trying to go bleeding-edge all the way around.
 

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SSTO RLV:s are an uncertain technology.
Since the payload mass might be something of the order of one tenth of the vehicle dry mass, even small dry mass increases wipe out the payload completely.
This is not so in a two stage rocket - not in the first stage nor in the second stage, each for different reasons. This leads to how in total a two stage rocket is not nearly as sensitive to dry mass growth. The difference of "sensitivity" between SSTO and 2STO could be ten fold.

Same applies for engine performance, propellant utilization etc etc...

The first operational systems should be robust and operable instead of high performance. Maybe in the future then if you have demonstrated things like low crew requirements and rapid turnarounds even for just a reusable first stage, can you start thinking of a reusable SSTO. In the past, or at the moment it is not worth pursuing directly as a vehicle building program.
 
F-14D said:
One example of the complexity was how early flights were to be conducted. X-33 would launch from Edwards AFB and then fly to Dugway Proving Grounds in Utah. The X-33 couldn't be flown back and the plan was that it would have to be trucked all the way back. One issue was that the X-33 on a trailer would not be able to fit under some of the highway bridges en route, so NASA was going to have to pay to have those bridges rebuilt.

That's an interesting observation about the logistics of an X-33 mission. I had seen artwork (presumably by John Frassanito & associates) showing X-33 mounted on the back of a 747. Whether the mods for carrying the X-33 could be worked into the existing Shuttle Carrier Aircraft or not was unclear. A new mate-demate assembly would certainly be required. But it might be a cheaper solution than rebuilding highway bridges.
 
Orionblamblam said:
F-14D said:
If the public isn't interested or think we're just repeating ourselves, they'll object to the money being spent on such "waste".

So? Once again, the public doesn't get to vote on spending. If they did, the US Federal budget would be a buck-o-five.
OT: Or you would have a Canadian-style Medicare. ;)
 
DC-X/XA Program Next Steps, AFRL Presentation from 20 October 2010:

http://www.ispcs.com/files/tiny_mce/file_manager/presentations/sponable.pdf

Could be just me, but on Page 5 I see a 3rd tiny pic in 'HAVE REGION' section alongside 2 which are already familiar...
 
mr_london_247 said:
Could be just me, but on Page 5 I see a 3rd tiny pic in 'HAVE REGION' section alongside 2 which are already familiar...

Do you mean this one??
 

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No, tank/cross-section articles, but realised Dynoman has previously posted another Sponable presentation with same pics:

http://www.secretprojects.co.uk/forum/index.php/topic,315.msg117346.html#msg117346
 
I'm curios about the developments, DC-Y, DC-1, X-33. I think they would have had problems trying to achieve .92 mass ratio. But it would have been easier to do than the Venture Star.
 

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