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European Shuttle Program Update
Rolo Tomasi writes "ESA's reusable launch vehicle demonstrator, Phoenix, was recently wind tunnel
tested to determine its low speed aerodynamics. A free flight for Phoenix is
planned for early summer 2004. In case you haven't heard of it yet,
here's an article from last year, describing the Phoenix/HOPPER concept.
Here's another page at ESA, but it seems to be available only in German. What's interesting is the first sentence of the DLR press release, stating that (my translation) 'Europe's future and
competitiveness in space substantially depend on an autonomous access to space and 'on a drastic decrease in the transport
costs of getting there.'"
The wings look really small, so is that a lifting body shuttle?
Actually, one design I saw was for a winged main booster. The idea behind it was when it detaches from the shuttle it could glide back down to earth.
But yes, the Space Shuttle wasn't exactly what the space program needed for the long term, it was just the cheap sucker that passed congress. Don't get me wrong, it served it's purpose.
But as far as going back to a capsule, well you could but I think part of our experimentation is attempting to actually create a vehicel that at some point could do a moonshot, land, launch, return, and refuel and get back underway in a short time. And yes, we do need a fleet of more traditional rockets, not so much because they are cheeper to build, but that whole issue of getting into higher orbits that the present shuttle just can't do.
Landing has one key advantage vs splashdown in the fact that even with the flying brick shuttle you have some control as to where you land and how you land. If you screw up a splashdown and hit.. for example... land, you are pretty much screwed.
Heat tiles are the cutting edge of technology... for 30 years ago. Modern metal alloys exist that are structurally strong, yet can also withstand the temperatures of re-entry directly without having ceramic tiles. My guess about the different approaches:
* Ceramic tiles = obsolete.
* Heat shield = more weight to carry up with you = inefficient for payload and fuel.
* Parachutes = explosives / mechanisms to release the chute are needed.
Wings & landing gear may be the safest option given that if the landing gear fails - you can still slide along the dirt and live. If you remember capsules sinking and astronauts nearly drowning on a regular basis with splashdowns, an airport landing is looking more and more desirable.
An alternative is to design for steeper/shorter reentry and to use multiple orbits to ensure correct positioning so that the landing could take place somewhere reasonable. This is what NASA wanted but it was nixxed by the USAF as they needed to be able to fly all the way down.
The ESA could select something more like the original NASA flight profile and thus make something reusable, for less money. Purely ballistic reentry vehicles are fine, but they don't scale up so easily.
See my journal, I write things there
not a pratical/scientific one. In a sense, by putting a man in space a government is saying "look at what our technical infrastructure can do." Nothing more.
This was the original reason behind the apollo program and winning the space race. Once NASA accomplished this, NASA was left with the difficult job of justifying itself, and arguably the reason why they have not had a sense of direction.
Many will not like this post with responses like;
1) We need to send a man to mars --
This would take a huge amount of money by anyone's standards. Once there, what does he do?? Plant another flag and take soil samples?? A robot could do this much cheaper. Before spending all that money on a mars mission maybe Dubya should give that prescription drug beneffit to the seniors that he promised.
2) We need man in space to mine exotic minerals from asteroids --
The fact is that it will always be economically cheaper to find those minerals on earth, no matter what. It would be cheaper to send a man to the bottom of the ocean to mine it there if need be. But why send a man to do a dangerous job when a robot can do it cheaper and more efficiently in the first place??
3) We need man in space to establish the new frontier where people can go to live --
Again, it will always be cheaper to find places on earth for people to live than to shuttle them (and all the supplies they need) to outer space. Right now it's taking 1.5 billion dollars to maintain a couple people on the international space station. If this was meant to be, how much is it going to cost to shuttle a 100 million of their fellow Americans to orbit?? To say that it will be cheaper in the future is to ignore the obvious. NASA isn't asking for less money to do their job, they're asking for more money. As it is, there is no way for them to replace the aging shuttles that like to blow up every few years. Maybe it will be cheaper in the (very) distant future, but in the history of the space program the cost has never gone down to send a few people to orbit. Maybe they could use atomic rockets. We can only imagine the fun when something goes wrong there, not to mention all the radiation spewed into the enviroment. Fusion power remains a dream occasionally energized by lasers in buildings the size of small cities for a blink of an eye.
I bet all that money that would be spent on new and improved space planes to replace the shuttles could buy vast tracts of homes built by Habitat for Humanity for people to live in. Maybe thay could take a few dollars that they were going to spend on new spacesuits and spend it on saving the enviroment we have.
Everybody has lots of ways to conquer the laws of physics to get man into space. But nobody has a way to conquer the laws of economics.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
Anti grave is not the answer either. The applied use of directed magnetic fields is interesting again though. The research into this stopped in the 1960s when the distance calculations to reach escape velocity on a field launch ramp was calculated at roughly 30 miles of ramp. The problem was that air density at the ramp hight of 13,000 feet was still too dense to take the velocity achieved without supper heating the payload! Seems to me in the Andes there are places the ramp hieghts could reach 20,000+ feet adjacent to the Altiplano but the ramp construction contraints were considered too great. Well we have much better mag lev and supperconductor tech now and we also have much better high altitude construction techniques. The only reason this tech is not been brought forward is the tech would need to be applied somewhere other than in the US! It would require real international co-operation and would in the long run be so much cheaper than rockets. Houston and the Johnson would go out of business. Fuel payloads could be launched also and staged late burning correcting vessels could also be devised. Get your mind away from rockets for just one second. Yes they are important for getting around once you gain escape velocity but they are a stupid and dangerous way to achieve it!
OH THE SHAME I fell off the wagon and use sigs again!
It wasn't a bird of fire, it was a bird who burned (Not that this makes it any better) and rose from the ashes.
That may not be such a bad name, ESA previous worked on a shuttle called Hermes, which where cancelled many years ago. Maybe they used parts of the Hermes design for Phoenix?
Reusable spacecraft are actually much cheaper to use, just not the way the Shuttle does it. The Hopper doesn't have any of that tile nonsense. From the third link (my translation): "Upon reentry of the compact Hopper, the reentry angle into the atmosphere is optimized in such a way that the resulting heat from friction is significantly lower than on the US Shuttle. Thus the delicate and expensive tiles can be replaced with a cheap and maintenance friendly heat protection system."
Did you know you can fertilize your lawn with used motor oil?
Yes, it's apparent that this ship is not manned. But the same rule applies -- what ever can be done in space, there will always be a cheaper more viable alternative on earth.
This is a knee jerk rant with all the stories of china/india other countries sending men to space.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
Actually, capsules are much safer than "space planes". Russians recently suffered a generalized computer failure on reentry and landed without any problem, far away from the expected landing spot. Oh, and you don't need to "splashdown" in water, it can be done on the ground too. Also, you don't need all that dead weight : wings and all the control and surfaces needed for the reentry. That's several additional tons you need to throw on orbit, tons you cannot put in the payload. So, if you take the shuttle motors and reservoir (you don't even need those expensive refillable boosters any more, but you can take them too), then replace the shuttle body by a (reusable) capsule, you have a much much cheaper (and efficient) reusable vehicle. And it is also safer. And it is able to lift an heavier payload on a higher orbit. And ... why the hell did they add those wings already ?
I guess it is an image problem. They want a "spaceship" ...
Kirinyaga
What metal could withstand 1,650 C? I am seriously curious here because nothing that I know of can even come close to withstanding that much heat for that long of time.
I remember reading a book about turojet (fan?) engines and how the blades, even made using fancy techniques such as single mold crystal or something like that, cannot withstand the heat inside a modern military jet engine and must use a series of complicated air ducts to vent fresh air over the metal. If they can't make a material to withstand the heat of an aircraft engine why would they be able to make a material to wisthand 10's of minutes of 1000+ C heat?
Your first point is absolutely valid to a certain extend.
/. is linking towards non-English sites, there is someone posting a translation in here. (t+5minutes: automatic ones like babelfish, altavista or google; t+20 minutes exerpts in a usable translation; t+1h a nice translation).
While I am a German native speaker, the majority of the information I read is
a) English
b) German with at least 20 per cent English buzzwords.
Every time
This is actually a good thing and the people who are doing these translations are heavyly dependant on your feedback.
From a pracical side, it would be not so nice not to point to non-English sites, when they are covering an interesting topic. As long as there are people here who are helping those people who have chosen to learn different languages, I don't see you being handicapped.
Btw. do I hear you volunteering to answer stupid questions from non-English-native-speakers to explain rare english words which can't be found in an online dictionary for some reason?
Its an old point, but worth repeating:-
I dont believe NASA/ESA will ever deliver
really cheap space transport - they are
good at some things, but they are just
not the right people to do it..
The X-Prize has yielded a whole raft of
promising new vehicles, all for a measley
$10 million. (remember the the shuttle is
$600 million per launch)
Just set up "competitions" for certain
objectives and let entreprenuers figure
out the rest..
"You lied to me! There is a Swansea!"
however, when are they going to fix the problems with long term space flight? we can have the greatest space ship ever designed, however, unless the issues faced, aka, bone density deterioration due to weightless environment and the ability to haul a large amount of supply of food etc.
Ulimately if there is ever to be a future in space travel and space "exploration", the dogma between the European Space Agency, Russian Space Agency and NASA have to be put to one side, pull all the collective resources together and focus on a common goal.
With out a common goal and unified direction all there will be as a result is 3 organisations duplicating each others R&D, whichm IMHO is not a very efficient way of spending tax payers money.
"The difference between pornography and erotica is the lighting" - Woody Allen
You obviously haven't read the "Common misconceptions" on ISR's website.
Here's a few you just made that are worth pointing out:
1. Materials not only exist, but are under mass production. Go google for nanotubes.
2. Actually, it's a giveaway. A 10-40B$ expenditure spread across 15 years? Or across many nations like the I$$? The war in Iraq costs a billion a week. Many skyscrapers, tunnels, bridges, and other architectural endeavors have cost much much more.
And considering that by making space accessible for a fraction of the amount any shuttle will ever cost (think 100$/kg on first cable, or 5$/kg when you'll have many many elevators, say, 50 years down the road), it will return the investment quite shortly after being built.
Worth pointing out is that the elevator also gives you the ultra-cheap inter-solar-system propulsion solution. Think 'Slingshot'. _BIG_ slingshot. No big engines required.
Could actually lay out a neccesity for that hot-aired russian nuke-reactor-on-mars-within-30-years idea.
So why are they laying their money on new shuttle designs? All we'll ever need is to put the initial cable in space. 2-7 shuttle launches, pending design. Then we can forget what a shuttle is altogether. Let alone design a new one.
Old men with old ideas would be my guess. Same reason the RIAA can't let go of its business model. No visionaries or evangelists among their decision makers, only solidified rigid-thinking fossils.
Too bad actually. We'd all reap the benefits. Cheap comms, cheap medicine...
So, anyone wanna lay down a couple of billion$ and design a new steam engine instead?
-
In summary, it's you, my American friend, who might really need black humour soon. After all, it's highly unlikely that the situation in Russia will become worse.
Future Wiki -- If you don't think about the future, you cannot have one.
The refractory metals are better, but less commonly used. Columbium/niobium is reasonable to form. Molybdenum and alloys like TZM take a bit more heat, but have a potentially annoing ductile to brittle transition point for systems that will cold soak. The state of the art is irridium coated rhenium, which doesn't melt until 2466 C / 4471 F.
We fabricated a TZM chamber a while ago at fairly high expense, but still burned through it after an extended length run:
burned TZM
This experience has convinced me that active cooling methods, like transpiration cooling, are probably a good idea for high reusability reentry vehicles.
John Carmack
P.S good luck with the X-Prize, Im rootin for ya.
Last time I checked you were using a cold liquid propellant. Does Armadillo have fabrication difficulties with such a design?
-OzJuggler.
Life's a buffer; you can only get out of it what you put into it! C:-)