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Orbital Space Plane Problems
FTL writes "NASA's next big step in space (after getting the remaining Shuttles flying again) is the construction of the Orbital Space Plane. It is a small vehicle designed to transport people to and from ISS. Jeffrey Bell takes a close look at OSP in this article and comes to the conclusion that it will result in yet another crippled vehicle. Sounds like what people were saying about the Shuttle's problems back when it was being designed."
The X-prize is suborbital. Still, supporting a similar orbital prize may very well be a good idea.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Orbital Space Plane @ orbital.com
Orbital Space Plane @ globalsecurity.org
If you are going to debunk the debunkers, please do it properly.
The atmosphere is responsible for "twinkling" yes.. but htat has nothing to do with stars being seen or not. The sky from the moon looks pretty much like the sky from earth, minus twinkling.
The reason you don't see starts in the photographs is because of EXPOSURE time. Lunar surface == bright, Astronaut in white moon suit == bright, remember this is directly reflect sunlight with no atmosphere to dim it at all.. therefore, the exposure time is very short, and that's why the stars don't register.
This isn't just a theory.. its' the same reason you don't take your picture indoors with a bright window or reflection behind your subject... because it casues everything else to fade to black.
Actually, during the late 1980's there were some serious studies of building a small spaceplane that could be launched from the top of a modified 747-200.
Essentially, the 747-200 would be fitted with a de-rated version of the Space Shuttle main engine, which will allow the 747 with the spaceplane on top to do a steep 35 degree climb to around 50,000 feet. The spaceplane, which has a small external fuel tank attached, would then launch at that altitude and fire its engines (essentially 3-4 RL-10's used by the Centaur upper stage) for a 7 minute flight to orbit. Because the launch happens at 50,000 feet, there is no need for the spaceplane to lug along a big load of propellant fuel, and that means it could carry a load as large as seven crew members or its equivalent weight in cargo to the International Space Station. I can envision by 2014 crews will visit the ISS either by using this new spaceplane or much-updated versions of the Soyuz spacecraft; ISS consumables and future extensions to the space station will be brought up by lifting them to orbit on uprated versions of the Atlas V and Delta IV Heavy rockets plus updated versions of the Russian Proton rocket.
Indeed, the guy who wrote it did sound like a smart ass.
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The United States has come to the point of a reusable space-plane a number of times and at the last minute gives it up.
Like the X-15. It flew, it worked, the engine worked, 1 man to almost space, it could have gone to space and back but the budget was cut.
http://www.hq.nasa.gov/office/pao/History/x15/c
Dyna-Soar
ttp://www.aerospaceguide.net/dynasoa
http://www.astronautix.com/craft/dynasoar.
X-24
http://www.astronautix.com/craft/x24a.htm
I was referring more to Mitsubishi's history of aerospace development than their cars.
Well,h tml
I currently work for NASA and I would like to dispell some of the ugly rumors you are spreading.
1)Space travel is not beyond us (we have already proven that).
2)Furthermore, NASA has been behind all of the most up-to-date space travel(that we know about).
3)Management is not the problem with the columbia disaster, it is only portrayed that way because the media needs someone to blame so people like you can be happy. Everyone involved in the disaster understood the risks and did everything they could to prevent a problem. We are not perfect, but that doesn't stop us from trying to be.
4)NASA does not have a monopoly on space travel. First of all, monopoly only applies to private companies, not government-funded programs (the website is www.nasa.gov NOT www.nasa.com). Secondly there are other space programs in the world who are less advanced, but face it, we are the most wealty country in the history of the world, if we didn't have the most advanced space program, we would have our priorities confused.
5)I think it is a great idea to have other agencies investigating options for space travel, however, do you really want a space vehicle built by corporate America where profits make decisions before safety? The reason NASA is a government-run entity is the fact that they can pursue new ideas and breakthroughs without the pressure of having to create something that is profitable (even though much of what NASA creates is). Take a look at http://technology.ksc.nasa.gov/spinoffs/spinoffs.
to see some of the things you take for granted that were created by NASA. (cordless drills, cellular technology, GPS, Air conditioning just to name a few)
6)You may not know that NASA is operating with essentially the same budget today that it had 15 years ago. Figure in inflation and you may realize how meagre the budget has become. The amount that is spent on NASA from your tax dollars is miniscule compared to our defense budget. NASA's annual budget is 14 Billion dollars, which may seem like a lot, but the treasury department spent 360 Billion in interest, 32 billion in education, 41 billion on roads,400 billion on social security, and 350 billion on the Dept of Defense. NASA's budget doesn't seem so bad, huh?
7)NASA doesn't just do space travel. There are many other branches that I don't even have time to elaborate about here. Look at www.nasa.gov and look at some of the projects NASA is working on, it may surprise you.
8)Writing your congressman/woman is a great idea, but maybe you should be telling them to increase NASA's already tightened budget so we can enjoy more of the benefits later. The only way to improve is to learn from our mistakes and move on. No one can predict whether or not our research into space will be useful someday, so why not explore all of our options?
--Derek Riley
What he says about "advanced technology" is pretty much spot on.
When you look at our "advanced boosters" - in a basic sense, all they are is old early cold-war-era ICBMs, retrofitted with Solid Rocket Boosters. Atlas, Delta, and Titan. The last REAL innovation in US booster technology was Saturn V.
I agree with several points he made - about how VTOHL is kind of retarded. Launching big heavy wings vertically, so the craft can land horizontally is ridiculous. But he overlooks some of the alternatives.
Lifting Bodies - X-33 was a spectacular failure - only because when confronted with adversity, WE GAVE UP. Part of that was the failure of the guys who set the budget unrealistically low in the first place, and let it overrun past the point of credibility. But if you want weight-savings in not sending wings up vertically, that's the way to do it. There's one real technicall challenge - an oddly-shaped fuel tank able to repeatedly deal with the pressurization cycle. And we just rolled over and quit when the first few attempts failed. I think that's sad.
Horizontal Take-off - Pegasus has been a spectacular success. If you're going to put wings on your craft, you may as well Horizontal Take-Off. Most of the launch fuel of getting a vehicle into space is used up in the first 5 miles. I don't know if there's a good way to fix this problem cheaply - we already "blew our wad" so-to-speak, but here's what we can do maybe in 10 years:
Justify the development of a new, VERY large multi-purpose transport aircraft - like the Galaxy C-5, only, in order to take advantage of economy of scale, use the same principle used in the JSF program. One plane that fulls multiple roles. Here are the roles:
Heavy Bomber (to replace the B-52).
Cargo Transport (to support loads the C-5 cannot handle)
Commercial Passenger plane (I know, we can't justify the Boeing double-decker, but at one point, it was at least worth thinking about).
Launch Vehicle Deployment.
Currently, the Pegasus can loft a tiny 1000lb payload into orbit. It's taken up to 40,000 ft by an L-1011, which is a pretty large plane. A plane on the scale of what I'm talking about could horizontally loft a next-generation spaceplane up to 40,000 ft, separate, and return to the ground, for mere peanuts compared to what it costs to prep your typical Atlas/Titan/Delta/Arianne. From 40,000 ft, scramjets can get this plane to 80,000 ft and Mach 8-12. (another technology we would need to develop, but it will save the weight of carrying oxidizer). Booster rockets can get it to Orbit. (either a SRB strap-ons, or perhaps the scramjets can be fed oxidizer).
Admittedly VERY complicated technology, but this is the evolution we were looking at 15 years ago with VentureStar, and other variants. And they were abandoned, due to lack of vision at the federal level. This lack of vision stems from a lack of a pissing-contest with the Russians, like we had when we were going to the moon.
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
First flight already. More at http://www.avweb.com/news/atis/181827-1.html.
That's a general aviation plane, lots of catching up to build spacecraft.
Like the X-15. It flew, it worked, the engine worked, 1 man to almost space, it could have gone to space and back but the budget was cut.
1 5/cover.html">X-15 project contributed to the development of the Mercury, Gemini, and Apollo programs as well as the Space Shuttle.
In the "old days", X projects were eXperimental projects. They were designed as one-off, disposable projects in order to test engines or airframes or design techniques. You built it, flew it, tweaked it, and flew it till you couldn't learn anymore (possibly to distruction). Then you took what you learned and built the real thing.
What was learned in the (a href="http://www.hq.nasa.gov/office/pao/History/x
Nowadays, X is more a buzzword than a project description. For example, the X-33 project was a disaster from start to finish. The last successful X project was the DC-X. Probably because nobody (politically) important expected to succeed, so nobody tried to kill the project until it started producing results.
Well, I currently work for NASA and I would like to dispell some of the ugly rumors you are spreading. 1)Space travel is not beyond us (we have already proven that). 2)Furthermore, NASA has been behind all of the most up-to-date space travel(that we know about). 3)Management is not the problem with the columbia disaster, it is only portrayed that way because the media needs someone to blame so people like you can be happy. Everyone involved in the disaster understood the risks and did everything they could to prevent a problem. We are not perfect, but that doesn't stop us from trying to be. 4)NASA does not have a monopoly on space travel. First of all, monopoly only applies to private companies, not government-funded programs (the website is www.nasa.gov NOT www.nasa.com). Secondly there are other space programs in the world who are less advanced, but face it, we are the most wealty country in the history of the world, if we didn't have the most advanced space program, we would have our priorities confused. 5)I think it is a great idea to have other agencies investigating options for space travel, however, do you really want a space vehicle built by corporate America where profits make decisions before safety? The reason NASA is a government-run entity is the fact that they can pursue new ideas and breakthroughs without the pressure of having to create something that is profitable (even though much of what NASA creates is). Take a look at http://technology.ksc.nasa.gov/spinoffs/spinoffs.h tml
to see some of the things you take for granted that were created by NASA. (cordless drills, cellular technology, GPS, Air conditioning just to name a few)
6)You may not know that NASA is operating with essentially the same budget today that it had 15 years ago. Figure in inflation and you may realize how meagre the budget has become. The amount that is spent on NASA from your tax dollars is miniscule compared to our defense budget. NASA's annual budget is 14 Billion dollars, which may seem like a lot, but the treasury department spent 360 Billion in interest, 32 billion in education, 41 billion on roads,400 billion on social security, and 350 billion on the Dept of Defense. NASA's budget doesn't seem so bad, huh?
7)NASA doesn't just do space travel. There are many other branches that I don't even have time to elaborate about here. Look at www.nasa.gov and look at some of the projects NASA is working on, it may surprise you.
8)Writing your congressman/woman is a great idea, but maybe you should be telling them to increase NASA's already tightened budget so we can enjoy more of the benefits later. The only way to improve is to learn from our mistakes and move on. No one can predict whether or not our research into space will be useful someday, so why not explore all of our options?
--Derek Riley
As a former employee of Lockheed Martin. I can tell you that this has been in the works for a while. A few years back they where working on a smaller version of the X-35 Shuttle to use as an escape vehicle for the Astronauts onboard the ISS. Seems that since the X-35 was written off for now due to the cost. A much smaller space plane would fit right into the project plans. This would save them money and accomplish the goal of transporting the Astronauts to and from the ISS after it's construction is complete. Seems like they could still use some of the proposed X-35 technology (Ramjets and such) on this smaller vehicle. Might as well use this project as a stepping stone to replace the aging Space Shuttle.
He also complains about the R&D cost estimate as being too low.
The Orbital proposal from the linked website giv an OSP mass of 48,700 lbs; it doesn't say how much is structure and how much is propellant. R&D costs for an aerospace vehicle typically range from $20,000 to $100,000 a pound. Assuming (as is likely given that it is a gov't managed non-evolutionary vehicle) that this program would be $100,000/lb, that would give a total development cost of probably less than $5 billion.
Does anyone know what the NASA estimate he is bitching about is?
Back in the sixties, during the "cold war", it was a matter of national importance that we "dominate" space and the funding was set appropriately. There was a lot of funding for training existing engineers and also encouraging students into the engineering field.
I lived through that. I still have many certificates and recognition papers from NASA that was awarded to me in High School ( I usually took the science fairs ). I don't see that any more, or at least not near the level of encouragement to get into engineering as I received.
Instead, as we passed from the Gene Krantz philosophies ( "Failure is *not* an option!") to the Dan Goldin business philosophy ("Faster, Better, Cheaper!"), it seems to me that Engineering has lost a helluva lot of its appeal, becoming much less a work of art and much more as mundane clerical work.
Personally, I have a hard time recommending any of my younger friends to go into Engineering unless its what their heart is driving them to do, as it did me. Engineering for me turned into a constant battle to justify my existence, eventually leading to my dismissal. Although I loved the artistry of design, there are a lot of starving artists out there. I never liked the idea of cutting corners to make something right now, but not made right. It went against the very core of my psyche to do so. I felt that when you were creating an artistic effort that would eventually be copied, possibly millions of times, one weighed the one-time cost of the effort of doing it right against the integral cost of fixing something not done right, integrated over all the things made that had to be fixed or replaced. My own analysis damn near always echoed those old cliches: " a stitch in time saves nine", "haste makes waste", and "if you don't have enough time to do it right, you must make enough time to do it over."
So we have these aging scientists and engineers who have actually done it, but many of us are now in completely different fields. I can show you engineers that used to build the systems in the 70's that are now working as greeters in Wal-Mart, or as countermen in hobby-electronics stores.
Although I loved working in the field myself, I can't see me trying to re-enter it as my experience is mostly with the older tools - tools I understood very intimately and had complete freedom to open up and re-code their algorithms if I discovered the mathematical functions inside did not accurately model what I was seeing in practice. The new stuff - I have no earthly idea how it works, or how to open it up and change it if need be. They would laugh me out of the building if I showed up with my trusty old Borland C++ compiler and VGA graphics packages.
Its going to be interesting, given the level of intimite knowledge required to do analysis of spaceflight sophistication, if the engineers they get can make enough time not only to understand the physics of the phenomena they are working with, and also keep abreast of the software packages they are allowed to use on the job. It took me over ten years before I felt I understood just some of the physics in my area, despite the fact during the entire time, I did not have to learn DOS over and over again, or have my previous tools fail to operate because I went from DOS 3.30 to DOS4.0... Or endlessly battle licensing issues.
The new guys have it a lot harder than I ever did.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
Your entire comment makes the rather broad assumption that air density is the same at sea level, 10km and 150km. I'm kind of thinking it drops pretty quickly.
.000460, air density at sea level is .002377, so air density at 45,000 feet is about 1/5 that of sea level (google rocks, chart 1).
It saves quite a bit of fuel because there is significantly less drag at 10km than there is at sea level. 10km would be, what, pretty much 35 thousand feet, but the service ceiling of an unmodified 747 is 45,000 feet (google owns you).
Air density at 45,000 feet is
So, if the 747 dropped the payload at 45,000 feet, and the payload gained altitude at a good rate, it would require significantly less rocket fuel than taking off from the ground. In addition, the payload could have smaller fuel tanks, which means smaller pipes, less structure and less insulation to fall off and ding a wing.