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New Shuttle Fuel Tanks Ready
confusion writes "NASA has completed the redesigned fuel tanks for the Shuttle scheduled to for launch in May or June of this year.
"On the new tank, NASA has reconfigured the struts and fittings where foam was prone to peeling off, and installed heaters to prevent ice from forming. The new tank has cameras that will allow ground workers to monitor for damage as the shuttle ascends.""
So when are they going to redesign the shuttle though?
The main problem on the antiquated space shuttles is the heat-resistant tiles. They're extremely expensive, and not very good. They're so soft you could problably crush a piece with your hands, which means they're easily damaged during flight (and we've seen the fatal results of that).
Troy Hurtubise, the Canadian who did the famous bear-proof suit documented in the movie Project grizzly, spent 18 years researching how to make a flameproof material, and finally has it. It's far more heat-resistant than the space shuttle tiles, far more durable, and far cheaper. A friend and I watched him testing it for a military representative last July, and got the whole thing on film (it was so interesting we hope to turn it into a documentary). His material would solve many of the space shuttle safety issues, and do it for cheap (and he has an impact-proof version as well, which provides a cheap way to prevent many of the deaths of soldiers in Iraq; that was the focus of the testing I saw).
Here's his site:
http://projecttroy.com.nexx.com/website/
The new tank has cameras that will allow ground workers to monitor for damage as the shuttle ascends
What are they gonna do about it when it is damaged from the ground?
And what are they going to do if they see damage, tell the crew to jump out?
"The new tank has cameras that will allow ground workers to monitor for damage as the shuttle ascends."
Not much of a reassurance to the crew though, are they?
Ground worker #1: "Looks like she's breakin' apart."
Ground worker #2: "Mm-hmm."
Ground worker #1: "We install brakes?"
Ground worker #2: "Nope."
Ground worker #1: "Ejection seats?"
Ground worker #2: "Nope."
Ground worker #1: "... So, how about them Cubs?"
Are they going to send one of the astronauts on an EVA walkaround inspection before re-entering this time? Truckers check their brakes before a big hill, why don't astronauts check the heat shield?
Is it just me, or does this seem more like a patch than a real fix? Rather than realizing that the foam is problematic and designing something that won't come off, they resort to finding ways of preventing the old stuff from coming off. Well, if it works, great, but it just feels unsatisfying.
Perhaps this is just a case of extending the life of aging spacecraft a little longer for the least expense so that more funds can be routed towards newer technology that doesn't have the same inherent problems. (Perhaps different ones. *g*)
Not only that, but if you apply this bearproofing technology to the shuttle program, you are ready to go for the Ursa Major mission.
Don't blame Durga. I voted for Centauri.
They've known about this problem for 20+ years. "But we never lost any important tiles." NOW they decide it's time to do something about the chunks of ice. If you needed any more evidence that NASA was a haven of groupthink, bureaucracy, and institutional cowardice, here it is.
Behold the riant ape! Beware, his crooked thumbs!
Obviously Spaceship One isn't an answer, as reaching space is much easier than acheiving orbit. Remember that orbit includes a huge horizontal velocity that Spaceship One wasn't even considering.
Of course, your point is still valid. It may well make more sense to use traditional rockets for lifting, and concentrate our manned efforts on a vehicle designed for human transport only. I'm not sure I agree with that approach, but it's certainly worth evaluating. Of course, we probably all agree that we need a shuttle replacement, just what we should develop is up for debate.
An AK-47 in the hand of the wearer would greatly enhance the ability of the ensemble see that no bear comes anywhere near.
Don't blame Durga. I voted for Centauri.
Umm... You know when they where doing project Pluto(A nuclear powered Ramjet Cruise Missile) They found out that the exhaust was barely radioactive, if it was radioactive at all.
Ohh and the project your are talking about is NERVA, and that was not canned because they were considered too dangerous. They were canned because of the 1963 ban on nuclear testing in the atmosphere. And the considered the exhaust from the NERVA rockets to be radioactive, which was hardly the case, but nonetheless blame the politicians.
You sir are an uninformed sheep.
The very last call I took at the IBM PC Help Center [which, I gather, is in peril of being relocated from the RTP to the PRC] was with the guy who administered the laptops that the astronauts took on the shuttle. Could only see about 100 of the 300 servers on his network, so we figured it was a networking problem [I was in networking, not laptops], and I spent three hours with him before we finally realized that it was the drivers for the PCMCIA bridge that were killing the ethernet stack. Updated the drivers and la voila - everything worked perfectly.
ANYWAY, this was early 1997, and he told me that the shuttle was filled with 8-bit processors dating from its design in the 1970s, and it was cheaper for them to have the astronauts carry light weight IBM laptops onboard as a form of an upgrade rather than ripping the beast apart at the seams and upgrading all those 8-bit processors to 32-bits [which I suppose nowadays would be 64-bits].
Wonder who they'll use for such sensitive equipment now that Big Blue has jumped in bed with Big Red?
Yep, NASA has an entire book available on their site documenting the building of the space shuttle. The Space Shuttle actually would have been much more advanced and safer then it is right now. But, Congress had given NASA a strict budget, and NASA had to build a space shuttle with the budget they had at the time which was if I remember correctly was around 1.2billion.
:-/
Considering some of the better designs needed nearly 4billion to be built, 1.2billion was way too little
Space is a red herring for recent administrations. They have no interest in space exploration because they well know the Rapture will occur here on Earth. Why jaunt around other planets when Jesus is coming home? It's far better (in their view) to spend money on Israel and wars, anything that helps contribute to the "End Times."
Okay this makes me nuts. This is like saying forget jets, the Comet crashed and was not practical so lets just stick with DC7s, Lockheed Connes, and Boeing Stratoliners. Props work, they are cheaper, and get the job done.
The Shuttle was totally over sold and under budgeted. For some reasons people seemed to think we could go from the "Spirit of St Louis" to a 747 in one step.
What would a shuttle built today look like using the same specs and the with funding?
1. It would use "green" fuels for the apu and RCS.
2. It would be all electric. No hydraulic system
3. It would use cermets or a metal thermal protection system.
4. Liquid flyback boosters instead of SRBs.
5. Have unmanned mode and maybe even some total unmanned versions with a bigger lift.
The failure of the shuttle program is the lack of learning we are doing from it. A shuttle replacement should have been flying by 1990 or 95. What I hate is it seems like everyone wants to take two steps back or a giant leap forward. Lets make small steady steps forward.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
We have put nuclear reactors into orbit before. On one of the missions, the rocket even blew up. The net gain in radioactivity? ZERO. The casing around the material was designed to be able to tolerate a rocket explosion. They recovered the material (every last gram) and reused it on a later mission. The problem is not garunteeing a 100% success rate, the problem is making sure that if something does occur, that the material doesn't get spewed all over the contry side. And that is orders of magnitude easier.
Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
Hello, is that Russia? Hi, well we managed to get our men into space ourselves this time, but err... haha, it's quite funny really, we might need a teensy bit of help getting them back!
"...a polyurethane foam applied with CFC-11 chlorofluorocarbon, was used on domes, ramps and areas where the foam is applied by hand." (Columbia Acident Investigation Report, disk version)
It was the hand-applied foam that came off. Also, the procedure for applying the foam was not modified as it should have been when CFC-11 ceased to be used on most of the tank. Had it been changed, there shouldn't have been a problem.
BTW: Freon is the term for "refrigerant." There are multiple freons. Sigh.
This sig seemed like a good idea at the time....
installed heaters
So your saying they put heaters....on a fuel tank?
Coder's Stone: The programming language quick ref for iPad
RTGs are potentially worrisome, but the fuel can be heavily protected as you mention. However, they are most often used as electrical power generators, not propulsion systems. RTG fuel is nasty stuff even before the RTG is put in use.
Fission reactors (not RTGs) that are not activated until orbit really aren't that much of a big deal on launch because they can be fueled with fresh U-235 which really isn't very radioactive or dangerous until you switch the reactor on and start generating fission products. The only issue is if they don't make it out of earth orbit and eventually the orbit decays. Powering an ion drive with one of these to do missions to the outer planets might make a lot of sense.
The scariest nuclear propulsion case a the high-thrust rocket used for the first or second stage liftoff. These have been successfully tested on the ground but never flown. They basically pack all of the power of a large commercial nuclear plant into a package only a few feet in diameter. They run full blast with little or no shielding. There is no way to heavily shield or isolate the fuel without impeding the huge heat transfer rate that is necessary to propel the massive amounts of propellant gas out the rocket.
These high-thrust rockets operate at the very fringes of material strength capabilities and probably have a high probability of disintegrating, spewing partially spent fuel and waste into the atmosphere. That's one reason that they've never been actually used.
NASA's tried to make something of the Shuttle. Unfortunately, during the process of constant compromises to get many missions behind the single transport project, the end product is not good at any job. It is a poor transporter of people, a poor platform for satellite launch/recovery, a poor cargo lifter, and finally a poor platform for deep-space missions.
The Shuttle was a nice try. We can give NASA due credit. But a bad idea is still a BAD IDEA. The Shuttle program should be broken into at least 3 major pieces.
[You have a stable society when some nut guns down a schoolyard and the law doesn't change.]
That's SLA-561V. A variant, SLA-561S, is already used on the shuttle's external tank for shielding during liftoff (it's what gives it its orange color). It's not good enough, however, for reentry; plus, there are some technical problems due to its relatively low strength.
There's always this wierd assumption around Slashdot that NASA is a bunch of idiots, and that they don't know more than a bunch of random people on the internet when it comes to (insert topic here). The number of different types of heat shielding that have been experimented with by Nasa is huge; it's not something that they take lightly. Depending on the mission, they look at what is avaialble, what they have budget for, and use what is best, just like what any reasonable person on Earth would do.
Seen on a Japanese food processor: "Not to be used for the other use."
If you could take a vaccine for the common cold once then you'd lose all that money for cold remedies. And if you could cure high blood pressure, cholesterol, diabetes and arthritis instead of managing these conditions then you'd make much less money. It is the opposite of the old saying about teaching someone to fish rather than giving them a fish for dinner. In this case, they'd rather that you were dependent upon them for the rest of your life.
In the same vein, the shuttle is very expensive but this is good for the companies that essentially strip them down and rebuild them for every launch, which is what they do rather than just reusing them. The SRBs are salvaged out of salt water and rebuilt. The shuttle is a prime example of pork barrel politics and make work projects. It is meant to make political capital for certain states, not to solve a problem. The contractors love being the only game in town and since they can charge a margin on top of subcontractors and equipment and software bought for the projects they never use things over again, they buy it all from scratch. It is a large waste of money, but good for the economy in a way if you like having the gov't fund what amounts to corporate and personal welfare.
Until there is a completely private alternative, accountable to shareholders instead of politicians at the trough, space travel will continue to be outrageously expensive and inefficient.
$#!^ happens, but why does it always have to happen to me???
1. The cameras arent new. Right now, the cameras on the tank are ATM cameras. They couldn't get the new cameras approved for manned space flight in time. These will be installed on future tanks (not the next one delivered, but probably the one after that)
2. Since the tank is actually a super thin aluminum shell with two more super thin aluminum shells inside of it (liquid oxygen and liquid hydrogen at something like -600 F) it needs insulation.
the foam was made to be more sticky and less prone to falling off.
The bipod (where the shuttle's nose connects to the tank) was espically prone to foam falling off of it and hitting the shuttle. So, what they did was put heaters in the base of the bipod to prevent the -600f tank about 2 inches away from freezing the thing solid.
The heaters only run untill just before liftoff, when the umbilical is detached and the shuttle launches.
Those are the two main things (the foam and the heaters) that the review commission required before they could fly again. Everything else is just extra.
Also, the shuttle is the mack truck of the space program. It can only go into Low Earth Orbit, not even into outer space. We need a better system. cspring
At least the cockpit electronics have been upgraded - to 32 bit computers (among others 386). I'd guess that that's just the part the pilots/astronauts interact with, the avionics is probably still the old hardware, which was not 8 bit, but something derived from IBM's S/360 line with 32 bit, but only 104k of proper core memory. If you want to know more, I suggest you read at least chapter four of Computers in Spaceflight: The NASA Experience
Only recently have Pentiums and other processors of the same level been qualified for radiation hardening in space applications (at the manned-spaceflight altitudes, which are full of radiation). The current level of technology has circuit pathways that are too small and are more easily affected by the exposure. (http://www.sandia.gov/media/rhp.htm --> decision to redesign the Pentium was only in Dec '98 and it was expected to take 2-3 years.)
Either way, whatever they eventually design to replace the Shuttle after its decommissioning in 2010 (or shortly thereafter) will likely be designed with 1990's technology.
The shuttle design in use today was picked from several concepts in the early 1970's.
They purposely picked a design that required NO NEW TECHNOLOGY TO DEVELOPE in order for it to be cheaper to build.
One of the rejected designs was a 2 piece craft that was 100% reusable..... Yup, exactly like SpaceShip One today.
Another design was a 1 piece craft that was 100% reusable. But that requried development of high speed ram jets that no one wanted to fund.
The primary computers on the shuttle were, in the beginning, three "hardened" IBM 360 mainframes. The 360 used 8 bit bytes, and 32 bit "words", the smallest addressable unit. That said, Im sure that some of the auxiliary systems use smaller CPUs. As cool as they are, Thinkpads havent ever been used for critical systems. The reason why they use laptops to do word processing and note taking isnt because they cant upgrade their 1970s era electronic word processors, but because their 1970s word processors were paper and pen.
> launching a shuttle when the ambient temps
> were well below the rated range for the SRB
Exactly - it's just like that. Except, the NASA engineers making the decision didn't have the data about the effect of cold on O-rings, while Rutan was quite well aware of the windspeed, and as a longtime aviator, should be very well aware of the dangers of wind shear (NASA routinely cancels launches, at big financial loss, if they think wind shear might be too high).
> I am trying to remember when a fully
> integrated shuttle stack was launched unmanned
> for testing purposes
Unless explicitly stated, all tests were unmanned. Only major tests listed; there were smaller tests going on almost daily. Tests listed for all shuttles being worked on at the time. I've probably left out some major tests, too, but I don't have forever to assemble the list.
Feb 15, 1977: Complete mated ground vibrational tests of airframe
Feb 18, 1977: The first unmanned captive flight of airframe (no engines)
Feb 22, 1977: The second unmanned captive flight (like above)
Feb 25, 1977: The third unmanned captive flight
Feb 28, 1977: The fourth unmanned captive flight
Mar 2, 1977: The fifth unmanned captive flight
Jun 7, 1977: Unmanned fully integrated ground fire test
Jun 18, 1977: First manned captive flight
Jun 28, 1977: Second manned captive flight
Jul 26, 1977: Third manned captive flight
Nov 15, 1977: First ferry flight test
Nov 16, 1977: Second ferry flight test
Nov 17, 1977: Third ferry flight test
Nov 18, 1977: Fourth ferry flight test
Dec 9, 1977: Complete approach and landing tests
Apr 21, 1978: First static test firing
Apr 24, 1978: Precombined systems tests
May 19, 1978: Second static test firing
May 30, 1978: Vertical ground vibrational
May 19, 1978: Third static test firing, 90% thrust
Jul 7, 1978: Fourth static test firing
Sep 20, 1978: Launch configuration vibrational testing
Jan 30, 1979: Start burnout mated vertical ground vibrational tests
Jan 30, 1979: Start orbiter mated vertical ground vibrational tests
Feb 3, 1979: Complete combined systems test
Feb 26, 1979: Complete mated vertical vibration systems test
May 4, 1979: Fifth static firing test (cont'd. Jun 12)
Jun 15, 1979: First SRB qualification firing
Jul 12, 1979: Sixth static firing test (Cont'. Oct 24)
Aug 6, 1979: Complete limit test
Oct 5, 1979: Complete setup and thermal tests
Nov 4, 1979: Static firing
Nov 12, 1979: Complete OMS qualification tests
Dec 16, 1979: Orbiter complete integrated test
Dec 17, 1979: Static firing, full 554 seconds, 100% power output, with proper reduced scaling and gimballing tests
Jan 14, 1980: Complete orbiter integration tests
Feb 14, 1980: Final qualification firing for SRB
Feb 28, 1980: Yet another full length static firing
Mar 20, 1980: And yet again.
April 16, 1980: Static firing again
May 30, 1980: And again
Jun 1, 5, and 16: More tests, this time for Colombia
Jul 12, 1980: Another firing test - and thankfully they did so many, because with how unpredictable rocketry is, they got burnthrough on this one, and were able to know about a potentially lethal problem and had time to rectify it.
Dec 4, 1980: Another static firing
Jan 5, 1981: Emergency egress test (manned)
Jan 17, 1981: Another static firing
Feb 2, 1981: Wet countdown test simulation
Feb 4, 1981: Continue a series of them
Feb 20, 1981: Flight readiness firing
Apr 12, 1981: STS-1 (manned, of course)
Those are the tests on the main shuttle craft. The 1/4 scale model underwent, to some degree, all of the tests listed above, plus full flight tests. Quarter scale models were built of both the SRBs and the orbiter. Needless to say, they were unmanned. They completed testing on Mar 31, 1980.
Here's Rutan's test suite:
A small series of unmated unmanned static test firings; no mated test firings that I am aware of, and I can't find anything online about any.
Seen on a Japanese food processor: "Not to be used for the other use."
> same tech for an orbital launcher ... which is impossible. Polybut/nitrous does not have enough ISP, period. Nitrous tanks are too heavy, period. Unless you mean "completely different tech" when you say "the same tech", you are completely incorrect.
... is not Rutan. Rutan has a rocket joyride company. Yes, he wants to reach orbit eventually, and that's a nice admirable goal. But he has nothing of the sort either on the ground or flying.
> All their engines are simpler than SSME, RS68, etc
And have the performance of a V2. V2s will never reach orbit, either. The extra complexity in SSMEs, RS68, etc, is not for no purpose. Yes, they're not the be-all, end-all of rocketry, but they at least have the *capability to reach orbit with any relevant amount of payload*
> OK, so I might have over-sold the parts count
It was obvious that you had before even reading the article. At the bare minimum, if you want a liquid fuelled rocket to perform well at all, you need a turbopump - pressurized tanks just weigh too much. Even the simplest theoretical design of a turbopump is still a fairly complex beast, and very sensitive to conditions inside the rocket. If I ever get into metalworking, I have a design for a theoretically simpler turbopump that I'd like to try out (an electric reluctance motor-driven one - no driving turbine, no seals in your fuel/oxidizer lines, etc), but even it would still be quite the piece of work, and unless I want to go SSME-style and have it staged, it won't perform as well as engines like SSMEs do.
See how these tradeoffs work? You can't get ISP for free; if you want a cheap engine, you can take a polybut/nitrous engine. If you want an engine that will get you to orbit? Tough, it's not going to happen. The ISP is too low and the tank mass too high. Anyways, back to the TR-106.
Not to mention that this is a LH/LOX engine. Are you aware of the difficulties in working with LH? Hydrogen embrittlement. Uneven boiloff. Insulation application (which has been a pain to NASA as well as other agencies, and one of the reasons why the Russian kerosene rockets, despite their much lower payload fraction, are so cheap). Pressure regulation. Temperature regulation. Hard to ignite when cold. And the obvious issue of the huge bulk size.
BTW, it doesn't have a single pintle injector; it has a single *fuel* injector. How do I know that there will be at least two injectors, ahead of time? Again, it doesn't make sense without that; liquid biprop rockets work by burning fuel and oxidizer. Both enter through "injectors". The more you preheat your fuel and oxidizer, the less complex of an injector you need, but then you need a more complex preheater. See how these tradeoffs work?
About the least "injector" you could get away with would be a simple hole in the combustion chamber attached to your oxidizer line, and you might get away with calling that something other than an "injector", but if you do that, you better have your oxidizer preheated or it'll never mix well.
> not sure how much catastrophic testing they did
As far as I am aware, it was *zero* catastrophic failure testing. They did a nice testing suite of glide tests, but the tests that they made public (and why on earth someone would hide something that makes them look safer - more testing - from the public, would be beyond me...) concerning their rocket engines are little short of embarassing. They did some non-integrated ground static firings, and after that they were firing on a fully integrated craft, midair, with a pilot in the cockpit.
Yeah, they're Square Jawed Engineers. And I admire that spirit, and I know that their test pilot supported them all the way. And the design has the potential to eventually be a very safe, reliable joyride. But I hope that everyone who straps themself into crafts like this know what they're getting into.
> the only manned spaceflight program
> functioning in the US
Seen on a Japanese food processor: "Not to be used for the other use."