Gerhardius noted a NYT article (you know the obnoxious deal) about new "shuttle" designs coming out of NASA. The payloads are riding up top to avoid debris.
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As long as we're no longer trying to send up cargo along with personnel, now might be a good time to revisit single-stage-to-orbit designs such as the Delta Clipper [wikipedia.org] and the Roton [wikipedia.org].
I don't recall any debris problems with either of these designs, although the leg design seriously needs to be rethought. If you have four legs, a failure of any leg results in disaster (witness the spectacular failure of the Delta Clipper). Six legs, on the other hand, would be far more stable...you could lose any three (provided they're not all adjacent) and still pull off a successful landing.
Single-Stage to orbit isnt feasible (yet). We need either a breakthrough in materials technology or propulsion performance. The rocket equation is
Delta-V = g * Isp * ln( MR )
where:
Delta-V: velocity required to achieve LEO (7.6 km/s best case scenario: but you need to add gravity and drag losses, add at least 1 km/s)
g: gravity (9.8 m/s)
Isp: Specific impulse of your propellant. This is an efficiency factor: 1 kg of propellant generates Isp kg of thrust. Hydrogen and Oxygen properly mixed generates an
Have you considered an alternate fuel, such as kerosene? While kerosene provides less specific impulse (I believe it's around 350 seconds versus hydrogen's 450), it's a lot easier to store...tanks for keresone are about 10% of the weight of tanks for a comparable amount of hydrogen.
Also I think I heard somewhere that good results were obtained from a propane/oxygen mix...that's another fuel that wouldn't require the excessive containment structure hydrogen demands.
another interesting fuel would be methane+02 right between kerosene and hydrogen in specific impulse and density. BTW the problem with hydrogen is not so much the cold but the density. A pound of kerosene is much smaller than a pound of hydrogen.
What happened was that the design in the NYT article retains some of the infrastructure of the STS, meaning a lot of the jobs that are associated with that massive pork barrel that also goes into orbit. The NYT article is basically a PR exercise by Thiokol to get the inside track for an STS replacement and it may very well work. However, look out for what Boeing and Lockheed will come up with as they too stand to lose a lot of subsidies contracts with a potential STS replacement. Having said that, the DC-X
It was originally an Air Force project. When video of the first test was shown at ConFrancisco in 1993, it was said that if it ever got transferred to NASA they'd kill it.
NASA was threatened by the Delta Clipper. A ground crew of 3 instead of 15,000? We can't have that! A NASA employee failed to connect the landing gear hydraulic line for one of the tests shortly after NASA took over the project.
These days NASA is more of a jobs program than a space program.
If you want to see what happened here's the video [gatech.edu]
IMHO, I don't think the strut failure was due to malice. I think it was simply a mistake/stupidity.
I got to watch several DC-X flights. I got to see it hover, move laterally, land, and the infamous 'dip & swoop' manuever.
I'm still dumbfounded that DC-X lost NASA's Reusable Launch Vehicle competition to the VentureStar design. Lockheed had an obviously bogus blue-sky design. McD had a working 1/3 scale proof-of-principle prototype.
A lot more design and testing would have been required to get to the full Delta Clipper orbital vehicle, but it still remains one of the better SSTO design ideas out there.
At least I got to see a rocket dance once. It was simply Incredible.
Well the Delta Clipper [wikipedia.org] had been transfered from the SDIO(DoD Star Wars office) to NASA, and upgraded when the crash occurred. It is propably safe to say that a NASA employee is the one who botched the hydraulic line though who can know if it was malevolence or incompetence that made him do it.
It should probably also be pointed out that when it was under SDIO control a hard landing cracked the shell requiring the rebuild when it was transfered to NASA so are you going to blame that accident on NASA malevolen
"For many in this thread, the goal is (1) NASA bashing and (2) celebrating the cult of What Might Have Been, of the Road Not Taken, and of My Powerpoint Works Better Than Your Hardware." Well maybe that is it, but it could also be called the process of good engineering. Good engineering usually involved thowing ideas out there, proposing new and different ways of doing things, and then tearing apart the ideas on paper before they get torn apart at high altitudes and velocities.
This is true of any Federal job, and most state government jobs as well. Any large commercial organization will also have this problem. It's not a NASA thing, it's an organizational thing.
I saw the case of a NASA employee sexually harass a student he was mentoring. He was told he couldn't mentor anyone else, but he wasn't fired.
As long as we're no longer trying to send up cargo along with personnel, now might be a good time to revisit single-stage-to-orbit designs such as the Delta Clipper and the Roton.
I don't recall any debris problems with either of these designs, although the leg design seriously needs to be rethought. If you have four legs, a failure of any leg results in disaster (witness the spectacular failure of the Delta Clipper). Six legs, on the other hand, would be far more stable...you could lose any three (provided
"As long as we're no longer trying to send up cargo along with personnel"
We are sending cargo. We sent a gyroscope the size of a washing machine this trip. The truth is, there is no other launch vehicle on the planet capable of boosting all the remaining pieces of the intenational space station into orbit. If the shuttle cannot complete its its missions, the space station cannot be completed.
Because single stage to orbit is the dumbest idea anyone ever came up with. Why in the world would you carry a ton of extra weight past a normal staging point? It's pointless. You waste so much energy carrying the dead weight. The performance gains by staging a rocket from 100% to even 50%/50% are immense, despite all the extra structure, components, and management to handle the staging. We're talking about taking the second 1/2 of your energy that you would normally spend on 100% of the weight, and only sp
SSTO with anti-matter propulsion or something might be perfectly fine.
I think that because of Star Trek, we are all beholden to the idea of anti-matter propulsion. That may come to pass in some distant future, but right now, it is a fairly unrealistic blue-sky idea.
I would put my chips on nuclear fusion as the long-term future, whenever we develop a replacement for chemical rockets. May years ago, Space.com cited some NASA experiments in the field: [space.com]
NASA engineers are developing a radically new type o
"Because single stage to orbit is the dumbest idea anyone ever came up with. Why in the world would you carry a ton of extra weight past a normal staging point?" Because fuel is dirt-cheap, at least by the standards of spaceflight costs.
What costs is high maintenance and long turn-around times... if you want cheap access to space, you want fully reusable, low-stressed, low-maintenance spacecraft which can operate like airliners (or, at least, like DC-3s).
If carrying a ton of extra weight will give you that,
Ah, I just did it myself. The grammar on the page was atrocious as well. If anyone else is up to it, the entire page could use a freshening up. There is far too much passive voice, poor comma usage and various other problems that seriously affect readability.
Not to mention the use of the word "whilst." Did a Brit write this article?
What they are effectively saying is, the 30 year experiment that was the space shuttle was a failure. Sure, a lot was learned - but now they are going back to the basic design concepts (upgraded with new tech, of course) of the 1960s. Live and learn.
Nah, what they're saying is they now realize it's stupid to try and do everything with a swiss army knife, when you can have a proper set of specialized tools instead. The fact that specialized tools came before the swiss army knife doesn't make them any less a superior solution.
Spaceplanes look cool. However spaceplanes are not what we need at this time. We were not in an advanced enough state of space usage to make good use out of it. We had far more need of speciality vehichles but speciality vehicles are BORING. NASA needed to sell itself after the spectacular moon landings. Hence we got the shuttle. Not only did it look cool, sound cool, and appealed to geeks it appealed to Congress as they spread it out across a great many districts.
Interesting comment about the ISS - I remember when the goal was to have it completed by 1992 in time for the 500th anniversary of Columbus coming to America. Now the worlds most expensive boondoggle will probably never be finished.
"We paid the price by being locked into LEO for how many years? " That was not the plan. NASA wanted the shuttle, and a space tug, and a space station. The idea was that they could use them to build large space craft in orbit so we could go to Mars and beyond. The shuttle was supposed to be totally reusable. Congress traded development costs for higher operational costs. The space tug and space station where killed. The shuttle was a good idea. The real problem was it was sold as a space 747. A space airliner
and start thinking about more fundamental engines built around magnetic/gravity principles.
Umm this is called science fiction. To us not tin-foil hat wearers there may be many means of travel in space (solar sails, ion trusters etc) but to get from earth to space atleast until we get the elevator, means rockets.
Well you could say that the experiement was a success - they learned that you probably shouldn't do it that way. The experiment continued until almost everyone could see that this is not the way to do it. If the shuttle program had been cancelled after Challenger, you'd still be getting spaceplane proposals.
NASA claims that the tile gap filler that has come loose was a result of vibrations on liftoff, NOT the result of falling debris...
So moving the return capsule up to the nose of the craft will prevent repeats of 1986 and 2003, but won't fix every problem. They should instead be trying to build a shuttle that won't rattle apart on takeoff.
They should instead be trying to build a shuttle that won't rattle apart on takeoff.
And why should they do that? That is a very, very expensive goal that is almost impossible to achieve. It is much more cost effective to simply go back to the way we used to launch spacecraft (and, note that old way is the way the Russians still launch their spacecraft).
Actually, they can do this easily. Just make the whole friggin' thing lighter. Less weight, less fuel, less thrust, less force, vibrations weaker and easier to dampen. And less stuff to fall off, so it can be attached better too. One of reasons shuttle vibrates so much is that it's so damn big. Make it a good solid brick, surviving in all conditions, instead of a sleek glider that can get blown to pieces by stronger wind. True shuttles are prettier that Sayuz capsules, but they suck at durability.
just make the whole friggin' thing lighter. Less weight, less fuel, less thrust, less force, vibrations weaker and easier to dampen.
IANA Physicist, but "less thrust" and "less force" to me means you aren't taking much up into space with you. If you can't take material with you, why would you want to go to space? Especially since (as the FA points out) it is much cheaper to use "older" technology to carry over 100 tons up each time (compared with the 20 tons the shuttle presently carries).
IANA Physicist, but "less thrust" and "less force" to me means you aren't taking much up into space with you. If you can't take material with you, why would you want to go to space?
To bring humans into space? If the separate vessel with cargo gets blown to pieces, no biggie, several $mln bite the dust, but nobody gets hurt. If there are humans on board, dump all the stuff that could kill them and that you can dump. Flying heavy cargo and crew in the same vessel was one of the biggest mistakes of the whole
By making the rockets from shuttle parts, the new plan would draw on the shuttle's existing network of thousands of contractors and technologies, in theory speeding its completion and lowering its price.
The most expensive part of the shuttle stack is the orbiter. Re-using the ET and the solid rocket boosters would save years of development time and yes, money.
They need to stick the Shuttle in the smithsonian and stick with the pieces that work.
Safer comes along with the cheaper in this seperation of designs, but it certianly is a return of the Super-apollo designs at the end of the 60's beginning of the 70's. Personally It looks like that NASA is at the end of their run in innovations of getting to space, they are damned good at exploring other planets and science in general but all of our hope of getting a real reuseable and safe space delivery systems lies completely in the Commercial sector.
Here's hope that someone in industry finds a really
I think NASA has spent enough subsidizing technological development. For decades that was seen as part of their purpose, so they pushed for cutting-edge advancements like reusable spacecraft. Now we have lots of technology and it's time to get down to the business of exploring space. Enough of new rockets.
Maybe the commercial sector will be the one to get a cheap reusable solution going well. But with this proposed cargo rocket carrying 100 tons, the they will have a lot of work to do to catch up as far as moving cargo goes. Whether you agree with it or not, NASA is planning on getting to the moon again, and then to mars; and that trip won't likely be accomplished by a ship that launches from the ground. Moving large amounts of cargo is important to NASA as it will be needed to accomplish their goals.
Wasn't the reason that NASA went to a shuttle was for reuse? To me, this "new" design looks like the apollo capsules. What is there for reuse and how will they reuse it? And then there is landing....
As parent says, the idea of reuse was solely to make things cheaper. Each shuttle flight ended up costing over $1b (according to the article). I have a difficult time calling that "cheap", especially when the Soyuz FG costs $50 million per launch. Now, this new design is apparently going to be MUCH more powerful than the Soyuz, but I seriously doubt it would come in line with the $1b/flight price tag.
The SRBs would be reused. I looks like the crew and equipment containers would not. But the idea here is to at least have a safer, interim system to get into space. One could later enhance the design with a reusable, winged crew vehicle, and possibly cargo container (although the latter might be worth keeping in space for raw materials.)
The diagram I'm looking at appears to be more like the Ariane 4 [wikipedia.org] or Ariane 5 [wikipedia.org] to me. The big middle one especially looks like the Ariane 5.
The best explanation I have heard is that the physics haven't changed.
We nailed the physics getting Apollo up.
So yes, at first glance it looks like Apollo/Soyuz. But instead of re-inventing Saturn V, they are taking the advances in engine design and applying them to the new rockets.
Makes sense to me, use the parts that worked well (boosters, capsules), ditch the parts that didn't (space plane).
I remember very clearly the first time I saw the shuttle concept proposed. It was 1967, I was in first grade,
NASA has 20,000 people on staff to maintain and rebuild the Shuttle fleet. Given that loaded labor rates, even for drudgery such as rocket maintenance, are probably in the $75k to $100k per year range, that means $1.5B per year is getting spent whether the Shuttles fly or not.
By the way: Loaded labor rate includes all expenses attributable to the employee being there - the cost of their desk, computer(s), health plan, the portion of the air conditioning and heating bill for their space, etc. It's part of w
You have to insulate tanks. Tanks have been insulated since cryogenic propellants have been used.
You can either insulate them from the outside or the inside. Outside you get debris. Inside you get debris. If your vehicle is on top, we don't care about debris outside. Inside, debris clogs our turbopumps and causes us to abort. And insulating the outside is cheaper.
Is the whole design of the shuttle overly fragile?
I understand that there are some sizable forces acting on the launch vehicle, but how can insulating foam do so much damage?
And, if insulating foam can damage the tiles, what about micro meteors or drifting debris from previous flights?
Isn't there a way to put a shrouding over the tiles that would be jettisoned with the fuel tank? Protect the tiles until the shuttle is free of the fuel tank and solid rocket motors.
Is the whole design of the shuttle overly fragile? Extremely. At least on launch. The liquid propellant container is made of layer of metal thin like tinfoil. Internal pressure keeps it from bending and breaking, but a small point pressure (bird's beak? Air gun dart?) is enough to pierce it - and make it explode. The shuttle itself is much more durable, but the foam remember that E=mv^2 so even small m at speeds the shuttle is going creates huge E, capable of seriously damaging it. Micrometeors and tiniest debri
Drop a coffee mug from three feet. What happens to ceramics when they recieve a sharp blow, even one with little force. Now things about 'little things' in supersonic winds. A thin layer of cloth isn't going to matter all that much. It may help, but is is worth the weight?
The whole engineering exercise is terribly weight constrained. You can imagine all sorts of solutions, but they add weight. My current favorite is to sandwich foam insulation between aluminum skins. This would prevent the insulati
Is the whole design of the shuttle overly fragile?
It's not so much that the Shuttle is fragile, it's that getting to space is a rough ride. Shuttle hardware is pretty solid stuff - but those solid rocket boosters are more like semi-controlled detonantions than anything else. If you've ever heard a launch, that "ripping" sound you hear are shockwaves from the solids. They will pretty much shake the sh*t out of anything. In this case, they rattle the tiles in the heat shield to the point where it opened up
It is strange that the new "shuttle" is not going to use something more interesting than just a rocket to lift off, like a SCRAM jet. I thought a SCRAM jet could lift a small new crew vehicle up above 50km and then the crew vehicle with 2 small boosters would disconnect from the jet and use the boosters to accelerate to the necessary speed, discard the boosters and use the remaining shuttle boosters to operate in the orbit. But they are going with another rocket design. Oh well, we just have to wait for
A scram jet will only get you to about 6-8 miles of altitude, I think (working on memory, might be wrong). In any event, it's a tiny fraction of the total altitude required. After that, it becomes a source of unnessary drag/weight/complexity. Plus, scramjets still don't work very well. It's like trying to keep a match lit in a hurricane.
Still though, it's a tantalizing goal. Here we sit in a sea of Oxygen and can't use any of it to get into space....as frustrating as having to bring ice to the North Pole
I can't believe that people are still denying the truth. Just yesterday, there was a SECOND article about the discover of Planet X. Planet X is returning on it's 4000 year orbit, which means that the race that enslaved us nearly 4000 years ago, the Niburu are coming back. It's not a surprise that we haven't had a successful manned space mission in the last few years. The Bush administration, NASA, the U.S. military and some of the most powerful corporations on the planet are covering this up. Why, you may ask? Because, they have a deal with the Niburu to spare their families from the enslavement when they arrive in a few years time. It is as it was written by the Sumerians and as Zecharaiah Sitchin translated (he is the only man on Earth who can read ancient Sumerian properly).
One of the requirements that the Niburu required as part of the deal is that humans will not make any manned flights off of the planet anymore. This is why we haven't been able to get a shuttle off the ground for so long. NASA talks about the supposed failures of various systems, but it's just a cover-up. Just like the cover-up they pulled off when the manned space station jsut a couple years ago hear strange sounds coming from the outside. The sounds were the sounds of a Niburu operative crawling around on the outside of the station. NASA later claimed it was just a bit of casing that had been damaged and needed to be fixed. What really happened? The anstronauts were reprogrammed to become Niburu operatives and came back to Earth to infiltrate NASA.
What about the dead astronaut found in the Arabian dessert? What? You didn't hear about that? Maybe it's because the Niburu controlled media don't want you to hear about it. They've been stirring things up on the global front to get the commoners at each other's throats so that we are in disarray when they arrive to enslave us. The real story is that a dead astronaut was found in the Arabian dessert after he had unwittingly announced the discovery of Planet X back in the 90s when that comet was going to slam into Jupiter. Why didn't Jupiter ignite into a big sun when that happened? Because the Niburu prevented the ignition with their awesome mind control. But they didn't do it to protect us out of goodness. They did it to protect us as property. So, this dead astronaut was found in the Arabian dessert. And that's why.
Don't fall for the cover-ups. Read the teachings of Zecharaiah Sitchin. And prepare for the intergalactic battle with the Niburu. Our politicians, military and business men have sold us out, so it's up to us to get armed to the teeth and fight when the invasion force comes. One of the most imporatant weapons you can get right now is a telescope and some astrophotography gear. Print out the photos of the impending approach of Planet X and post them everywhere online and in real life. Make sure that everyone knows about the conspiracy. This ain't no time to go wastin' away in Margaritaville.
Might you be willing to share some of the "groovy pharmaceuticals" you are partaking in? If your writings are any indicator, they seem to be of exceptional quality and potency.
What about the dead astronaut found in the Arabian dessert?
Okay, at first I thought this guy was off his chum. But then I googled "Arabian Dessert", and sure enough: http://www.thebirthday.com/recipes.html [thebirthday.com]
Birthday Recipes,Birthday Cake Recipes,Birthday Recipe Ideas From TheBirthday.Com
"Muhallabia ~ an Arabian dessert
Ingredients:
1/2 cup rice, picked, washed and soaked in 1/2 cup milk
5-1/2 cups milk
1/2 cup sugar
a handful of almonds, blanched*and sliced
a few drops rose water
a few pistachios. choppe
This has been discussed a lot lately, with a leak / release (I don't remember which) back in April. This article makes it sound like the official announcement is closer, and still close to the details we heard in April. For a good overview, here [wikipedia.org] is the WP entry.
What this essentially is saying is that NASA is deciding, now, that the booster for the next-gen vehicles will be Shuttle-derived. There'd been talk about using the Delta-4 instead. What this doesn't describe is the capsule itself (the Crew Explo [wikipedia.org]
From the article: "Just as important, officials and private experts say, the small rocket for astronauts would be at least 10 times as safe as the shuttle, whose odds of disaster are estimated at roughly 1 in 100."
So the odds of a shuttle flight ending in disaster are 1 in 10!?!?
We've had two shuttle disasters, which by their calculations would mean we've had 20 flights. Columbia's fateful flight was number 113, the current one is 114. That has odds of less than two percent of a disaster by my reckoning.
I think you misread. The article says odds are 1 in 100. Shuttle odds (according to the engineers - the bese people to ask) are roughly 1/100. A little better than that, actually. The new shuttle derived vehicles are looking to be 1/400.
This sentence is actually intelligible to people who know proper English.
Just as important, officials and private experts say, the small rocket for astronauts would be at least 10 times as safe as the shuttle, whose odds of disaster are estimated at roughly 1 in 100.
The whose in this sentence refers to the Shuttle, meaning that it's the Shuttle which has 1 in 100 odds of disaster, not the replacement.
For heaven's sake - can't you tell what in the sentence ""Just as important, officials and private experts say, the small rocket for astronauts would be at least 10 times as safe as the shuttle, whose odds of disaster are estimated at roughly 1 in 100."
I know they're falling back to the Apollo-style basics here, but this is still, in some ways, compromising efficiency and performance in light of crew safety, which is important. However:
"A ship in a harbor is safe. But this is not what ships are built for."
I would be fine with the new design concepts if we use a Crew Return Vehicle design. One, it can carry more people and a small amount of cargo. Two, it can also be placed atop like an Apollo-style capsule. Three, it is more reusable. Think of it as a mini-Orbiter.
Reusing and readapting the ET/SRB devices is a frugal idea as well. We just need something to routine get up and back to the ISS. Perhaps we should also look into making an in-orbit shuttle that stays in space and can move between LEO, the ISS, and the moon.
It is very frustrating how people get fixated on the wrong things when something bad happens. As far as I know, debris falling from a spacecraft have caused 1 accident ever (someone please correct me if I'm wrong). That's out of hundreds of previous accidents. Though I'm sure the designs main goal was not to eliminate this problem, it annoys me how they try to sell it on that point.
This sounds a lot like the "Big Dumb Booster" design -- a big rocket made of repurposed shuttle parts -- from Stephen Baxter's hard sci-fi Manifold [livejournal.com] trilogy.
Nice to know someone at NASA is doing their reading.:)
First of all, Spaceref.com had this story back in the early part of July, which was posted already on Slashdot: NASA Plans to Build Two New Shuttle-derived Launch Vehicles [spaceref.com] which outlined essentially the same things as the NYT article.
Given that the shuttle fleet is nearing obsolescence and that it is a 30+ year old design, it's a good idea to move on. And why not use components that have been proven to work already? It simplifies the engineering needed to construct the new vehicle.
Despite all the people who aren't rocket scientists fantasising about space elevators, perhapsotron drives and the like, it's becoming obvious that we are going to be physically limited to this planet for a long time to come. The amount of shit that has to be poured into the atmosphere to get any really significant payload into orbit means that if any large scale use is found for space, the damage from existing global warming is likely to fade into insignificance. The effects on the climate of the Krakatoa
The Shuttle has a great deal of maneuverability while in space both for rendez-vous with sattelite positions or the ISS, and for re-entry positioning. This was one of the design principles that allow for much more spontaneous (read, easier, not easy) reshcduling of re-entry and deployment. Even the Soyuz capsules seem to have some kind of retro-rocket design. The crew capsule nor the main booster seem to have (given the pictures on the NYT site) no retro-rockets visible. Any ideas on where they went, wh
Way to base your conjecture on a cheap graphic that was probably slapped together in a few seconds by someone who probably knows more about PR than they do about rockets.
Lets face it, you must first follow the money. Sure, it sounds like a good idea to reuse the currect parts of the shuttle to leverage existing parts and technology. But we are looking at a 35 year old design. We can't come up with anything better? Maybe it's not cost savings... It turns out that (ATTFA) Dr. Horowitz, one of the leading proponents for the resue of old technology, turns out to be the head of "ATK Thiokol, where he now leads the company's effort to develop the new family of rockets". Hmmm, I
In looking at these plans, I can't imagine how this is not a hole-in-one for NASA. It goes along with the less-is-more approach that made three astoundingly successful Mars rover missions. The shuttle was great and all, but I don't understand people saying "This is like taking a step back." If it doesn't blow up, then I'd say it's taking a huge step forward. And this new design has (potentially) five times the cargo capacity of the shuttle. This is enough to get me excited about the space program again.
However, either of these designs will require serious reconstruction work at canaveral: they are substantially taller than the assembled shuttle, and so will not be able to be built in the present shuttle assembly building, nor be able to use the present launch pad.
Other than at the ISS, we won't have any platform for performing experiments in space, now that we're reseparating the cargo from its users. Wonderful idea, NASA.
What we've basically created are resupply modules for the ISS. I don't see how this is in any way a Shuttle replacement.
IIRC, they painted the main tanks on the first 2 shuttle launches, but it was determined that all the white paint they appied to the main tank added to much wieght to it so they went back to brown unpainted tanks.
From TFA: [...] in theory speeding its completion and lowering its price.
That, indeed is why NASA is the leading agency for doing efficient, reliable and cheap innovation -- in theory. That is why Burt Rutan's SS1 project went over budget, it was irrisponsible, it did not win the Ansari X price and -- in fact -- it crashed. Whaha.
-- In theory, there is no difference between practice and theory.
You are correct. Challenger's SSRB failure was caused by a faulty O-ring, the failure of which was caused by cold weather and temperature cycling. Basically, it was a materials engineering issue.
Amazing to me how many people seem to have an incorrect grasp on history.
The Russians have been launching over land for decades. The cynic in me says that they chose Florida because this guy [congress.gov] had seniority in the US Senate about the time NASA was choosing a launch site.
Launching close to the equator gives you a large advantage since you already have the centripetal velocity from the earth's spin. Russia has launch sites very far north, but then you waste energy getting the rocket up to the same speed.
That's one of the reasons to launch in florida. The water is another one (falling debris won't hit anyone's house).
OK, I'll give you the centripetal velocity point. But, politics is never far away from government decisions. Why else would Houston host the (Lyndon B) Johnson flight center? Or, why does Cleveland host a Nasa site -- the (Senator John) Glenn Center? And, why does Alabama host the Marshall Center (take a look at the history of the Senate for the state of Alabama)? Sorry. This complaing of mine is totally off topic, but the politics around NASA pisses me off.
You could consider it, but you would then need more fuel or lighter payloads. Launches get more efficient the closer you get to the equator since the Earth is spinning (which is why the shuttle always goes east). AZ, NM, and NV are all farther north.
This is also why Boeing built SeaLaunch [sea-launch.com] for satellite launches: they can drag the launch vehicle out to the equator to get as much momentum as possible out of the Earth's rotation.
They're cheaper, safer, better, awesomer, and nowhere near as Rube Goldberg-esque as the shuttle.
Did you even read the Wikipedia article? Cheaper - "Development costs might be roughly equivalent, in modern dollars, to the cost of developing the shuttle system" - the technology for this currently doesn't exist, which means additional R&D is required (more $$$) - moving the elevator along the cable would require an enormous power source (so big, in fact, it wouldn't fit on board), so we're talking about addit
That must be because Star Trek, like Apollo and Soyuz, was a child of the sixties. I think that this design looks more like a Soyuz ( see http://en.wikipedia.org/wiki/Soviet_space_program [wikipedia.org] ) with a humongus Apollo command module than anything else. It's even going to parachute to land rather than water. This is a 60's soviet design with new materials and electronics and a different flag on the side.
The issue with the shuttle is; it's an incredibly complex machine, and some of the problems it was designed to handle are very difficult problems.
Yes, the Shuttle is a complex machine. I've heard that over and over again each time I see a shuttle launch program on TV, or when astronauts talk about it.
That is precisely the problem... not the ice damage or the configuration. Any engineer from any discipline can tell you that each time you add a new part or increase the complexity of a machine that you are
Whatever happened to single-stage-to-orbit? (Score:5, Interesting)
As long as we're no longer trying to send up cargo along with personnel, now might be a good time to revisit single-stage-to-orbit designs such as the Delta Clipper [wikipedia.org] and the Roton [wikipedia.org].
I don't recall any debris problems with either of these designs, although the leg design seriously needs to be rethought. If you have four legs, a failure of any leg results in disaster (witness the spectacular failure of the Delta Clipper). Six legs, on the other hand, would be far more stable...you could lose any three (provided they're not all adjacent) and still pull off a successful landing.
Not Feasible (yet) (Score:3, Informative)
Delta-V = g * Isp * ln( MR )
where:
Delta-V: velocity required to achieve LEO (7.6 km/s best case scenario: but you need to add gravity and drag losses, add at least 1 km/s)
g: gravity (9.8 m/s)
Isp: Specific impulse of your propellant. This is an efficiency factor: 1 kg of propellant generates Isp kg of thrust. Hydrogen and Oxygen properly mixed generates an
Re:Not Feasible (yet) (Score:2)
Have you considered an alternate fuel, such as kerosene? While kerosene provides less specific impulse (I believe it's around 350 seconds versus hydrogen's 450), it's a lot easier to store...tanks for keresone are about 10% of the weight of tanks for a comparable amount of hydrogen.
Also I think I heard somewhere that good results were obtained from a propane/oxygen mix...that's another fuel that wouldn't require the excessive containment structure hydrogen demands.
Re:Not Feasible (yet) (Score:2)
Amateurs have been exploring propane
-everphilski-
Re:Not Feasible (yet) (Score:2)
Re:Whatever happened to single-stage-to-orbit? (Score:2)
The NYT article is basically a PR exercise by Thiokol to get the inside track for an STS replacement and it may very well work. However, look out for what Boeing and Lockheed will come up with as they too stand to lose a lot of subsidies contracts with a potential STS replacement. Having said that, the DC-X
Delta Clipper (Score:5, Interesting)
It was originally an Air Force project. When video of the first test was shown at ConFrancisco in 1993, it was said that if it ever got transferred to NASA they'd kill it.
NASA was threatened by the Delta Clipper. A ground crew of 3 instead of 15,000? We can't have that! A NASA employee failed to connect the landing gear hydraulic line for one of the tests shortly after NASA took over the project.
These days NASA is more of a jobs program than a space program.
Re:Delta Clipper (Score:2)
A NASA employee failed to connect the landing gear hydraulic line for one of the tests shortly after NASA took over the project.
That's an interesting accusation...can you cite any sources?
Re:Delta Clipper (Score:5, Informative)
Delta Clipper Experiment [nasa.gov]
Wikipedia [wikipedia.org]
If you want to see what happened here's the video [gatech.edu]
IMHO, I don't think the strut failure was due to malice. I think it was simply a mistake/stupidity.
I got to watch several DC-X flights. I got to see it hover, move laterally, land, and the infamous 'dip & swoop' manuever.
I'm still dumbfounded that DC-X lost NASA's Reusable Launch Vehicle competition to the VentureStar design. Lockheed had an obviously bogus blue-sky design. McD had a working 1/3 scale proof-of-principle prototype.
A lot more design and testing would have been required to get to the full Delta Clipper orbital vehicle, but it still remains one of the better SSTO design ideas out there.
At least I got to see a rocket dance once. It was simply Incredible.
-I.V.
Re:Delta Clipper (Score:3, Informative)
It should probably also be pointed out that when it was under SDIO control a hard landing cracked the shell requiring the rebuild when it was transfered to NASA so are you going to blame that accident on NASA malevolen
Re:Delta Clipper (Score:3, Insightful)
Well maybe that is it, but it could also be called the process of good engineering. Good engineering usually involved thowing ideas out there, proposing new and different ways of doing things, and then tearing apart the ideas on paper before they get torn apart at high altitudes and velocities.
I'm sure NASA does do a lot of
Re:Delta Clipper (Score:3, Interesting)
This is true of any Federal job, and most state government jobs as well. Any large commercial organization will also have this problem. It's not a NASA thing, it's an organizational thing.
I saw the case of a NASA employee sexually harass a student he was mentoring. He was told he couldn't mentor anyone else, but he wasn't fired.
Re:Whatever happened to single-stage-to-orbit? (Score:2)
As long as we're no longer trying to send up cargo along with personnel, now might be a good time to revisit single-stage-to-orbit designs such as the Delta Clipper and the Roton.
I don't recall any debris problems with either of these designs, although the leg design seriously needs to be rethought. If you have four legs, a failure of any leg results in disaster (witness the spectacular failure of the Delta Clipper). Six legs, on the other hand, would be far more stable...you could lose any three (provided
Re:Whatever happened to single-stage-to-orbit? (Score:2)
We are sending cargo. We sent a gyroscope the size of a washing machine this trip. The truth is, there is no other launch vehicle on the planet capable of boosting all the remaining pieces of the intenational space station into orbit. If the shuttle cannot complete its its missions, the space station cannot be completed.
Re:Whatever happened to single-stage-to-orbit? (Score:3, Insightful)
Next-Gen Rocket Engines (Score:3, Informative)
I think that because of Star Trek, we are all beholden to the idea of anti-matter propulsion. That may come to pass in some distant future, but right now, it is a fairly unrealistic blue-sky idea.
I would put my chips on nuclear fusion as the long-term future, whenever we develop a replacement for chemical rockets. May years ago, Space.com cited some NASA experiments in the field: [space.com]
NASA engineers are developing a radically new type o
Re:Whatever happened to single-stage-to-orbit? (Score:3, Insightful)
Because fuel is dirt-cheap, at least by the standards of spaceflight costs.
What costs is high maintenance and long turn-around times... if you want cheap access to space, you want fully reusable, low-stressed, low-maintenance spacecraft which can operate like airliners (or, at least, like DC-3s).
If carrying a ton of extra weight will give you that,
Re:Whatever happened to single-stage-to-orbit? (Score:2)
Not to mention the use of the word "whilst." Did a Brit write this article?
Kind of sad... (Score:5, Insightful)
Re:Kind of sad... (Score:3, Insightful)
Not sad, facing reality. (Score:2)
Not only did it look cool, sound cool, and appealed to geeks it appealed to Congress as they spread it out across a great many districts.
We paid the price by being locked into
Re:Not sad, facing reality. (Score:2)
Re:Not sad, facing reality. (Score:2)
That was not the plan. NASA wanted the shuttle, and a space tug, and a space station. The idea was that they could use them to build large space craft in orbit so we could go to Mars and beyond.
The shuttle was supposed to be totally reusable. Congress traded development costs for higher operational costs. The space tug and space station where killed.
The shuttle was a good idea. The real problem was it was sold as a space 747. A space airliner
Re:Kind of sad... (Score:2)
That doesn't mean however the shuttle was a failure.
We have learned a great deal with how to design vehicles that can interoperate between low earth orbit and on the ground.
Two of the most difficult aspects that needed to be understood before taking our next step.
NASA seems to have a problem deciding though what that is going to be.
I personally think we need to get rid of this idea of rockets, and start thinking about mor
Re:Kind of sad... (Score:2)
Umm this is called science fiction. To us not tin-foil hat wearers there may be many means of travel in space (solar sails, ion trusters etc) but to get from earth to space atleast until we get the elevator, means rockets.
Re:Kind of sad... (Score:2)
Re:Kind of sad... (Score:2)
Hey, leave my personal life out of this, will ya?
Won't fix the problem (Score:2, Informative)
So moving the return capsule up to the nose of the craft will prevent repeats of 1986 and 2003, but won't fix every problem. They should instead be trying to build a shuttle that won't rattle apart on takeoff.
Re:Won't fix the problem (Score:2)
And why should they do that? That is a very, very expensive goal that is almost impossible to achieve. It is much more cost effective to simply go back to the way we used to launch spacecraft (and, note that old way is the way the Russians still launch their spacecraft).
Re:Won't fix the problem (Score:2)
Just make the whole friggin' thing lighter. Less weight, less fuel, less thrust, less force, vibrations weaker and easier to dampen. And less stuff to fall off, so it can be attached better too. One of reasons shuttle vibrates so much is that it's so damn big. Make it a good solid brick, surviving in all conditions, instead of a sleek glider that can get blown to pieces by stronger wind. True shuttles are prettier that Sayuz capsules, but they suck at durability.
Re:Won't fix the problem (Score:2)
IANA Physicist, but "less thrust" and "less force" to me means you aren't taking much up into space with you. If you can't take material with you, why would you want to go to space? Especially since (as the FA points out) it is much cheaper to use "older" technology to carry over 100 tons up each time (compared with the 20 tons the shuttle presently carries).
And less stuff
Re:Won't fix the problem (Score:2)
To bring humans into space? If the separate vessel with cargo gets blown to pieces, no biggie, several $mln bite the dust, but nobody gets hurt. If there are humans on board, dump all the stuff that could kill them and that you can dump. Flying heavy cargo and crew in the same vessel was one of the biggest mistakes of the whole
Re:Won't fix the problem (Score:2)
Thats one of the reasons for a push for a capsule, the heat shield design is much simpler, better understood, and cheaper.
Anyone else... (Score:2, Funny)
By making the rockets from shuttle parts, the new plan would draw on the shuttle's existing network of thousands of contractors and technologies, in theory speeding its completion and lowering its price.
Well, I guess they did say "in theory"...
Yup. It's true. (Score:2)
They need to stick the Shuttle in the smithsonian and stick with the pieces that work.
-everphilski-
Re:Yup. It's true. (Score:2)
They already did. [si.edu]
It's not about safer, it's about cheaper (Score:2)
Personally It looks like that NASA is at the end of their run in innovations of getting to space, they are damned good at exploring other planets and science in general but all of our hope of getting a real reuseable and safe space delivery systems lies completely in the Commercial sector.
Here's hope that someone in industry finds a really
Re:It's not about safer, it's about cheaper (Score:2)
Re:It's not about safer, it's about cheaper (Score:2)
Whether you agree with it or not, NASA is planning on getting to the moon again, and then to mars; and that trip won't likely be accomplished by a ship that launches from the ground. Moving large amounts of cargo is important to NASA as it will be needed to accomplish their goals.
The way
the new shuttle design (Score:2)
Apollo? (Score:2)
Back to the future. (Score:2)
Yes. It was supposed to same money. It didn't.
To me, this "new" design looks like the apollo capsules.
Me to. So?
What is there for reuse and how will they reuse it?
Not much, and they won't.
And then there is landing....
See also: Apollo.
You could have RTFA.
Re:Back to the future. (Score:2)
Re:Apollo? (Score:2)
Re:Apollo? (Score:2)
Re:Apollo? (Score:2)
Physics (Score:2)
The best explanation I have heard is that the physics haven't changed.
We nailed the physics getting Apollo up.
So yes, at first glance it looks like Apollo/Soyuz. But instead of re-inventing Saturn V, they are taking the advances in engine design and applying them to the new rockets.
Makes sense to me, use the parts that worked well (boosters, capsules), ditch the parts that didn't (space plane).
I remember very clearly the first time I saw the shuttle concept proposed. It was 1967, I was in first grade,
Re:Apollo? (Score:2)
By the way: Loaded labor rate includes all expenses attributable to the employee being there - the cost of their desk, computer(s), health plan, the portion of the air conditioning and heating bill for their space, etc. It's part of w
A Room Full Of Monkeys... (Score:2)
Re:A Room Full Of Monkeys... (Score:2)
A Giant Broom (Score:2)
Cow's gone, close the door. (Score:2)
The proverbial cow has left the barn, time to close the barn door.
Don't worry about the hole in the wall until chickens start escaping.
When will NASA start anticipating problems instead of just overreacting to previous ones?
Re:Cow's gone, close the door. (Score:2)
You can either insulate them from the outside or the inside. Outside you get debris. Inside you get debris. If your vehicle is on top, we don't care about debris outside. Inside, debris clogs our turbopumps and causes us to abort. And insulating the outside is cheaper.
Think of it as the lesser of two evils.
-everphilski-
Overly fragile? (Score:3, Interesting)
I understand that there are some sizable forces acting on the launch vehicle, but how can insulating foam do so much damage?
And, if insulating foam can damage the tiles, what about micro meteors or drifting debris from previous flights?
Isn't there a way to put a shrouding over the tiles that would be jettisoned with the fuel tank? Protect the tiles until the shuttle is free of the fuel tank and solid rocket motors.
Re:Overly fragile? (Score:2)
Extremely.
At least on launch.
The liquid propellant container is made of layer of metal thin like tinfoil. Internal pressure keeps it from bending and breaking, but a small point pressure (bird's beak? Air gun dart?) is enough to pierce it - and make it explode.
The shuttle itself is much more durable, but the foam remember that E=mv^2 so even small m at speeds the shuttle is going creates huge E, capable of seriously damaging it.
Micrometeors and tiniest debri
Re:Overly fragile? (Score:2)
The whole engineering exercise is terribly weight constrained. You can imagine all sorts of solutions, but they add weight. My current favorite is to sandwich foam insulation between aluminum skins. This would prevent the insulati
Re:Bring back the Delta Clipper! (Score:2)
It's not so much that the Shuttle is fragile, it's that getting to space is a rough ride. Shuttle hardware is pretty solid stuff - but those solid rocket boosters are more like semi-controlled detonantions than anything else. If you've ever heard a launch, that "ripping" sound you hear are shockwaves from the solids. They will pretty much shake the sh*t out of anything. In this case, they rattle the tiles in the heat shield to the point where it opened up
back to basics? (Score:2)
Re:back to basics? (Score:2)
Plus, scramjets still don't work very well. It's like trying to keep a match lit in a hurricane.
Still though, it's a tantalizing goal. Here we sit in a sea of Oxygen and can't use any of it to get into space....as frustrating as having to bring ice to the North Pole
The Shuttle Problems are a Sham (Score:4, Funny)
One of the requirements that the Niburu required as part of the deal is that humans will not make any manned flights off of the planet anymore. This is why we haven't been able to get a shuttle off the ground for so long. NASA talks about the supposed failures of various systems, but it's just a cover-up. Just like the cover-up they pulled off when the manned space station jsut a couple years ago hear strange sounds coming from the outside. The sounds were the sounds of a Niburu operative crawling around on the outside of the station. NASA later claimed it was just a bit of casing that had been damaged and needed to be fixed. What really happened? The anstronauts were reprogrammed to become Niburu operatives and came back to Earth to infiltrate NASA.
What about the dead astronaut found in the Arabian dessert? What? You didn't hear about that? Maybe it's because the Niburu controlled media don't want you to hear about it. They've been stirring things up on the global front to get the commoners at each other's throats so that we are in disarray when they arrive to enslave us. The real story is that a dead astronaut was found in the Arabian dessert after he had unwittingly announced the discovery of Planet X back in the 90s when that comet was going to slam into Jupiter. Why didn't Jupiter ignite into a big sun when that happened? Because the Niburu prevented the ignition with their awesome mind control. But they didn't do it to protect us out of goodness. They did it to protect us as property. So, this dead astronaut was found in the Arabian dessert. And that's why.
Don't fall for the cover-ups. Read the teachings of Zecharaiah Sitchin. And prepare for the intergalactic battle with the Niburu. Our politicians, military and business men have sold us out, so it's up to us to get armed to the teeth and fight when the invasion force comes. One of the most imporatant weapons you can get right now is a telescope and some astrophotography gear. Print out the photos of the impending approach of Planet X and post them everywhere online and in real life. Make sure that everyone knows about the conspiracy. This ain't no time to go wastin' away in Margaritaville.
Dear Sir (Score:2, Funny)
Re:The Shuttle Problems are a Sham (Score:2)
Re:The Shuttle Problems are a Sham (Score:2, Funny)
Re:The Shuttle Problems are a Sham (Score:2, Funny)
Okay, at first I thought this guy was off his chum. But then I googled "Arabian Dessert", and sure enough: http://www.thebirthday.com/recipes.html [thebirthday.com]
Kind of old news.... (Score:2)
What this essentially is saying is that NASA is deciding, now, that the booster for the next-gen vehicles will be Shuttle-derived. There'd been talk about using the Delta-4 instead. What this doesn't describe is the capsule itself (the Crew Explo [wikipedia.org]
This stat HAS to be wrong (Score:2)
"Just as important, officials and private experts say, the small rocket for astronauts would be at least 10 times as safe as the shuttle, whose odds of disaster are estimated at roughly 1 in 100."
So the odds of a shuttle flight ending in disaster are 1 in 10!?!?
We've had two shuttle disasters, which by their calculations would mean we've had 20 flights. Columbia's fateful flight was number 113, the current one is 114. That has odds of less than two percent of a disaster by my reckoning.
Whe
Re:This stat HAS to be wrong (Score:2)
-everphilski-
Re:This stat HAS to be wrong (Score:2)
FTFA: "..the shuttle, whose odds of disaster are estimated at roughly 1 in 100."
Mod parent -1: Poor Reading Comprehension Skills
I think you're used to "Slashdot grammar" (Score:2)
Just as important, officials and private experts say, the small rocket for astronauts would be at least 10 times as safe as the shuttle, whose odds of disaster are estimated at roughly 1 in 100.
The whose in this sentence refers to the Shuttle, meaning that it's the Shuttle which has 1 in 100 odds of disaster, not the replacement.
Re:This stat HAS to be wrong (Score:2)
Duh, don't you know anything about statistics? you can easily find data to support your point in anything.
Re:This stat HAS to be wrong (Score:2)
whose refers to the shuttle
ODDS OF 1:100 for the shuttle.
Too Simple, Really (Score:4, Interesting)
"A ship in a harbor is safe. But this is not what ships are built for."
I would be fine with the new design concepts if we use a Crew Return Vehicle design. One, it can carry more people and a small amount of cargo. Two, it can also be placed atop like an Apollo-style capsule. Three, it is more reusable. Think of it as a mini-Orbiter.
Reusing and readapting the ET/SRB devices is a frugal idea as well. We just need something to routine get up and back to the ISS. Perhaps we should also look into making an in-orbit shuttle that stays in space and can move between LEO, the ISS, and the moon.
Why not just use magic? (Score:2)
Blastoffius!
Debris fixation? (Score:2)
Screw that, let's do a REAL redesign. (Score:2)
big dumb booster (Score:2)
Nice to know someone at NASA is doing their reading.
Whatever happened to winged lifting vehicles? (Score:2)
So what happened to the non-kludge, reusable lifting vehicle? Isn't it about time to build a new one, using existing designs and componet parts?
--dave
Public and Private Next-Gen Designs (Score:2)
Given that the shuttle fleet is nearing obsolescence and that it is a 30+ year old design, it's a good idea to move on. And why not use components that have been proven to work already? It simplifies the engineering needed to construct the new vehicle.
Then there is the pr
We're not going to leave the planet just yet... (Score:2)
Something I don't understand. (Score:2)
Re:Something I don't understand. (Score:2)
Obvious reason to reuse parts (Score:2)
It turns out that (ATTFA) Dr. Horowitz, one of the leading proponents for the resue of old technology, turns out to be the head of "ATK Thiokol, where he now leads the company's effort to develop the new family of rockets". Hmmm, I
Simple is better (Score:2)
too tall for current infrastructure (Score:2)
Well this renders space experimentation useless. (Score:2)
What we've basically created are resupply modules for the ISS. I don't see how this is in any way a Shuttle replacement.
Re:Nasa says looks are not important... (Score:2)
Paint didn't help the foam situation (Score:2)
-everphilski-
Re:When posting NYT links... (Score:2)
Use the rss syndication link instead [nytimes.com]. Such links can be obtained from New York Times Link Generator [blogspace.com]
Re:When posting NYT links... (Score:2)
Or, you could do what 90% of us already do, we use a fake (or secondary) e-mail address to register an account with the NYT.
Re:Efficient,reliable,cheap - chose any 2 :-) (Score:2)
That, indeed is why NASA is the leading agency for doing efficient, reliable and cheap innovation -- in theory. That is why Burt Rutan's SS1 project went over budget, it was irrisponsible, it did not win the Ansari X price and -- in fact -- it crashed. Whaha.
--
In theory, there is no difference between practice and theory.
Re:Debris caused challenger disaster? (Score:2)
Amazing to me how many people seem to have an incorrect grasp on history.
Re:Debris caused challenger disaster? (Score:2)
Re:A bit too enthusiastic IMO.. (Score:2)
The launches are done in Florida so the craft can be over water almost immediately after takeoff...that big tank's gotta fall somewhere...
Re:A bit too enthusiastic IMO.. (Score:2)
The Russians have been launching over land for decades. The cynic in me says that they chose Florida because this guy [congress.gov] had seniority in the US Senate about the time NASA was choosing a launch site.
Re:A bit too enthusiastic IMO.. (Score:2)
That's one of the reasons to launch in florida. The water is another one (falling debris won't hit anyone's house).
Re:A bit too enthusiastic IMO.. (Score:2)
Re:A bit too enthusiastic IMO.. (Score:2)
This is also why Boeing built SeaLaunch [sea-launch.com] for satellite launches: they can drag the launch vehicle out to the equator to get as much momentum as possible out of the Earth's rotation.
Re:Two words... (Score:2)
Did you even read the Wikipedia article?
Cheaper
- "Development costs might be roughly equivalent, in modern dollars, to the cost of developing the shuttle system"
- the technology for this currently doesn't exist, which means additional R&D is required (more $$$)
- moving the elevator along the cable would require an enormous power source (so big, in fact, it wouldn't fit on board), so we're talking about addit
Re:It looks like Star Trek! (Score:2)
Re:engineering scapegoats (Score:3, Interesting)
Yes, the Shuttle is a complex machine. I've heard that over and over again each time I see a shuttle launch program on TV, or when astronauts talk about it.
That is precisely the problem... not the ice damage or the configuration. Any engineer from any discipline can tell you that each time you add a new part or increase the complexity of a machine that you are