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Japan Tests Reusable Rocket
HobbySpacer writes: "Japan's ISAS (Institute for Space and Aeronautical Science) is testing a sub-orbital rocketship called the Reusable Rocket Vehicle Test (RVT). A video of a recent test flight is available. (Alternate source.)
According to Space News, the vertical-takeoff-vertical-landing vehicle
was built on an annual budget of $400k and assisted by volunteers from the Japan Rocket Society. The highest flight so far is 25m but the priority is technology development and low-cost operations, i.e. learning to run a rocket vehicle like a jet. Gradually, the flight envelope will be expanded and later more powerful engines and lighter components will be tested." Low budgets, encouraging volunteer participants -- now that's the way to run a space program!
"Like the DC-X project, the approach is a throwback to the successful X projects of the 1950s when great progress was made by progressing in small steps with small dedicated teams and modest budgets. (As with the X-15, at least 2 or 3 vehicles should be built because if you don't lose at least one during testing, you aren't pushing hard enough.) Perhaps the U.S. will return to this approach, as well, since the mega, 10 bleeding edge technologies at once, all or nothing approach of the X-33 failed miserably."
That's only $160 per centimeter! Damn those Japanese are efficient!
better than the japanese transforming robot project!
I can just see it. NASA dropped the Delta Clipper because it didn't fit their plans. The Japanese will pick it up and run with it. Fifteen years from now, everyone will be flying Honda and Toyota rockets....
This is why I was interested to read an article at the somewhat notorious discussion site adequacy.org detailing how to make space travel and exploration less elitist and more widespread.
This article shows and provides backing for widening the franchise of people we send to space. Meanwhile, this one shows the possible threats we the human race may face from embarking on our seeming destiny among the stars (NB: Both these articles are controversial in nature)
My own opinion is that space needs a public-private partnership in order to best take advantage of the best the state and the private sector has to offer. All nations realise this to some extent just now, but the Japanese and Europeans much more so than the americans. We need to do similar here in the USA.
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Japan doesn't have a military? That's new.
Actually, Japan is among the top 5 military spenders world wide. And has an extremely modern Air Force and Navy.
The Japanese fly Mitsubishi/Boeing built F-4s and F-15s. And they are working on a new advanced F-16 class fighter, as well as buying 767 based AWACS aircraft from Boeing/Ratheyon.
The Japanese Navy has a number of Aegis class DDGs, similar in all respects to the US DDGs of the Burke class. The Japanese Army uses a very nice tank called the Type 74.
Japan is a strong ally of the US in Asia and is vital to US warfighting plans for Korea or other hotspots around the South China Sea.
Some Links to DC-X:
The really sad thing is, we'd likely almost be at the operational SSTO stage now, if we hadn't killed DC-X. . ..
In fact, on the X-15 page you link to, you give a prime example of why they might object:
I'd have to say that, of course more than one prototype should be built, but it's rather insensitive to snidely say that "if you don't lose one during testing, you're not pushing hard enough".
---------The early bird gets the worm, but the second mouse gets the cheese.
Damn I can go at least 100 meters with my estes Model rockes for 8 bucks an engine.. not reusable... but the body is :)
Damn... too much anime...
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Further, your notion that the US approach of science and technology as a "side-effect" is no longer true. Here's an excerpt from an article on Japan's technology policy, which can be found here:
"Traditionally, the public sector in most countries has been an important source of funding for basic scientific research.(6) As recently as 1995, the Japanese government contributed 22 percent of the nation's U.S. $140 billion in total R&D expenditures, while the U.S. government chipped in 35 percent of that country's U.S. $179 billion in R&D expenditures.(7) At first glance, it would appear that government support for basic research is alive and well."
"However, if we examine the numbers more carefully, we find that funding for "pure science" is indeed drying up. If one considers purchasing power parity, Japan's total R&D expenditures for 1995 are cut nearly in half, to U.S. $78 billion.(8) Even if we assume that the bulk of public money goes to fund basic scientific research, this means that only U.S. $17 billion is available for this purpose each year."
"By comparison, using the same assumption, the U.S. government is providing roughly U.S. $63 billion on behalf of basic science. The important element here, however, is the decline in military outlays on behalf of scientific research resulting from the end of the Cold War. Not only have overall budgets been cut, but there has been a fundamental change in philosophy regarding the most efficient way to obtain leading-edge technology."
"Given the limited applicability of products typically funded by the U.S. government, whether for military or aerospace applications, it is often hard to justify massive government investment in the basic research underlying such products. It is far more economical to rely on the private sector for such research, and simply tailor the resulting technology to military needs or purchase the end products outright. Consequently, there has been a shift from a "spin off" to a spin on" policy. Rather than the government financing basic scientific research through Pentagon programs such as the Defense Advanced Research Projects Agency (DARPA), which gave birth to the Internet, and then "spinning off" the resulting technologies for private sector commercialization, it is increasingly turning to the private sector for "dual use" technologies that it can "spin on" into military applications."
As for seeds of destruction, how is it that after supporting Japan's defense needs for over 50 years, the United States hasn't been eclipsed by Japan economically?
Remember the 1980s, when suddenly every American businessman was reading books about Japanese business practices? Well, the Americans learned a lot, and managed to make painful changes that turned the American economy around.
Unfortunately, Japan is having a tougher time making the infrastructure changes it really needs. Japan's banking industry is a mess, and the Keiretsu system has shown weakness throughout the 1990s.
Finally, your contention that a Japanese military would become "unbeatable within 25 years" is pure conjecture, and the thought that the Japanese could have a working missile defense system within 10 years is fantasy. There are many primarily political reasons this is true, as this National Bureau of Asian Research paper indicates.
If you want to talk about Asian superpowers, think China, my friend.
Read the EFF's Fair Use FAQ
Run the numbers.
With a 400 Isp engine, one percent of the vehicle landing mass can kill 40m/s of velocity. That is over 80 mph, which an efficient VTVL vehicle could expect to have as its terminal velocity.
A parachute masses more than 1% of its load.
There are lots of other factors that can push the decision either way, but it is certainly within the realm of feasible engineering decision.
John Carmack
Yes, this is very similar to what I am working on.
www.armadilloaerospace.com
Their current vehicle is a good deal larger than ours, has an aeroshell, and significantly, uses liquid hydrogen / liquid oxygen, a much more potent and difficult propellant than the hydrogen peroxide we use.
On the other hand, my project has been a lot faster and cheaper. I have spent about $50k and we have been working on it for nine months, versus their $400k and four years.
Our first up scale vehicle is going to be ready in a few months. It won't go very high or fast, but we can carry a person on it...
Next year, at the very least, we will have a supersonic manned rocket ship.
John Carmack
This is an outrage. Renewable rockets are going to be the end of the rocket industry as we know it. If we can simply reuse rockets, what will be the incentive for rocket users of all kinds to buy new ones? Think of the hundreds of jobs that will be lost because of this new found effieciency. We should throw away all used rockets and waste millions of dollars on complete replacements to help supplant this industry which is an integral part of our economy.
F-bacher
James Tiberius Kirk: "Spock, the women on your planet are logical. No other planet in the galaxy can make that claim."
"When It's Done", of course.
The space shuttle uses hydrogen. The problem with liquid hydrogen is that it has very low density. Six TIMES lower than other materials. This makes EVERYTHING bigger and hence heavier. Tanks, engines, pipes, pumps the lot. Extra weight in a rocket is not good.
Secondly, liquid hydrogen (LH) is a deep cryogenic fluid- the insulation values needed to keep it are very high, and this adds mass, plus it has lots of nasty habits like condensing oxygen from the air- LOX reacts with loads of things explosively.
If you do the simulations for an entire rocket, the performance of LH/LOX is entirely comparable to kerosine/LOX fuels- kerosine is much denser, lighter engines etc; but kerosine doesn't give as much kick per unit of fuel. So your rocket ends up heavier (more kgs of fuel), but the 'dry weight' is less. But this heavier rocket burns weight off much more quickly and hence goes as far as the LH/LOX.
Another advantage? Kerosine is a lot cheaper than hydrogen, even allowing for needing more of it. Kerosine can be carried in trucks.
Another? The kerosine/LOX rocket is much smaller (easier to build and transport).
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Low budgets, encouraging volunteer participants -- now that's the way to run a space program!
An extreme version of this philosophy is central to the Portland State Aerospace Society, Portland State University's group operating under the auspices of the IEEE Aerospace and Electronic Systems Society (AESS). Check out in particular our ongoing work on our Inertial Navigation System, which currently costs out at around $500. All of our work is open source, and is specifically targeted at usability by other amateur rocketry groups.
In the long run, Japan is going to prove to the United States of Armed-erica that not having to support a pork-barrel military has its advantages. The Japanese are able to divert their funds and ingenuity to real science and productivity
Well, actually quite a bit of our technology has been developed for the military. For example, look at how air travel came to be. It started off as some people tinkering around on their own time (like the Wright brothers), and was eventually adopted by the military and the technology advanced very rapidly. Fighter planes and bombers were designed for the military and because of WWII our planes started using jet propulsion (this had been worked on before the war, but development was really pushed along during WWII). That is the same technology that was used to design the commercial aircraft currently available.
Also, look at the history of rockets. While the Chinese did invent fireworks many thousands of years ago, most modern rocketry comes from inventions like the German V2 rocket (invented by Von Braun if my memory serves me correctly). While those rockets were mostly used for things like bombarding England, they were the same design used later for space exploration and I'm sure are pretty similar to the Japanese rocket mentioned above.
That's just my opinion... now let the flaming begin...
I know I would.
I've hit Karma 50 and gotten a Score:5, Troll... I win!
science is a religion
You probably don't want to be launching anything out of a mine shaft at supersonic speeds. (You probably don't want to be launching anything until you have the engines running, as it would be bad to find yourself thousands of feet in the air on a ballistic trajectory without thrust... but that's another issue.) Since you don't really need the ultra-high performance of magnetic propulsion, you might as well put a discarding sabot (cradle) on the bottom of the vehicle and launch it with steam. Recover the sabot by parachute or something. If you can pop out of the tube at 500 MPH, you've just saved the equivalent of about (pops up the calculator) 23 seconds of accelerating vertically at 2 G's thrust, which would otherwise cost you (assuming 430 seconds specific impulse, more calculator action) almost 10% of your fully-fuelled mass. You'll lose some of that to increased air drag from going so fast so low, but that's still a lot.
--
Scientists restrict study to entire physical universe; creationist
That's the way to run anything. The employees are happy, because they aren't doing it for money (hence the volunteering) but for the job itself and the goal in mind, and the results are astounding.
We do this now with Open Source. Many organizations are on route to this style. Globalization will stifle us to death otherwise.
Screw 3...
Volunteer! Now, instead of running Seti@home, You can mill rocket parts in your garage out of all that magnesium alloy you have sitting around.