#71
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Hubble Question...
wrote in message ... A hundred fold decrease in cost is a HUGE decrease. For high tech gadgetry, the typical decrease is typically about ten fold from initial model to balls out mass production. Couldn't we get close to it with a fleet of fully reusable shuttles that can be operated and serviced like todays commercial jets? Electronics have had similar decreases. The first electronic calculators were over $300. Just last week, I bought a very nice solar powered desktop calculator with an oversized LCD for only $1! |
#72
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Hubble Question...
"Bootstrap Bill" wrote:
Couldn't we get close to it with a fleet of fully reusable shuttles that can be operated and serviced like todays commercial jets? Thats an open question. It took a lot of years and experience to get commercial jets to where they are today. Even so, there is still a metric buttload of maintenance and support involved, it's just clumped together at intervals rather than being between individual flights. D. -- The STS-107 Columbia Loss FAQ can be found at the following URLs: Text-Only Version: http://www.io.com/~o_m/columbia_loss_faq.html Enhanced HTML Version: http://www.io.com/~o_m/columbia_loss_faq_x.html Corrections, comments, and additions should be e-mailed to , as well as posted to sci.space.history and sci.space.shuttle for discussion. |
#73
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Hubble Question...
In article , wrote:
A hundred fold decrease in cost is a HUGE decrease... Definitely so. That sort of massive improvement has never been done in one leap before. On the other hand, to quote the late Max Hunter (chief engineer for the Thor IRBM, later the basis of Delta), when that comment was made to him: "The human race has never done anything as stupid as we've done in space." No major advances in basic propulsion science, i.e. no dilithium crystals, impulse drive or anti-gravity engines nor is there likely to be. Chemical rockets are going to be around a long time. Probably so, but that doesn't mean that chemical rockets are in a state of perfection which permits no major improvements. Too much of the accepted wisdom in chemical rocketry is just the first thing that happened to work when people were in a hurry in the 1950s. The alternatives are poorly explored, and the current technology is in no way optimum. Also, "nor is there likely to be" is gross hubris. If you added "soon" to that, I might agree, with reservations. No economies of scale and highly unlikely space craft will ever be mass produced like Toyotas. There won't be mass production of spacecraft without major improvements in propulsion, which probably won't happen soon. But there is plenty of room for somewhat lesser economies of scale. Having reusable spaceships merely cost as much as major airliners would be a massive improvement... and there is no clear reason why they couldn't, since they should actually be simpler. Since it is so expensive, only governments can afford to do it... An increasing fraction of space launches are for private customers, and there have already been privately-developed space launchers (a few). If you assume that development of a reusable spaceship has to cost billions and billions, then definitely only government can do it. But that is an assumption, not a self-evident fact. That's not to say costs can't be reduced, just that it is unrealistic to expect a couple of orders of magnitude reductions. I would say that a more accurate statement is that it is difficult to *prove* that such a reduction is possible. The notion is not ridiculous; even high-performance experimental aircraft typically operate at only perhaps ten times their fuel costs... and that is *several* orders of magnitude better than today's rockets. There is no obvious law of nature which prevents reusable rockets from getting down into the same range. -- MOST launched 30 June; science observations running | Henry Spencer since Oct; first surprises seen; papers pending. | |
#74
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Hubble Question...
In article ,
Derek Lyons wrote: Couldn't we get close to it with a fleet of fully reusable shuttles that can be operated and serviced like todays commercial jets? Thats an open question. It took a lot of years and experience to get commercial jets to where they are today. Even operating and servicing like today's cranky high-tech experimental aircraft would be an enormous improvement. -- MOST launched 30 June; science observations running | Henry Spencer since Oct; first surprises seen; papers pending. | |
#75
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Hubble Question...
In rec.radio.amateur.space Henry Spencer wrote:
In article , wrote: A hundred fold decrease in cost is a HUGE decrease... Definitely so. That sort of massive improvement has never been done in one leap before. On the other hand, to quote the late Max Hunter (chief engineer for the Thor IRBM, later the basis of Delta), when that comment was made to him: "The human race has never done anything as stupid as we've done in space." No major advances in basic propulsion science, i.e. no dilithium crystals, impulse drive or anti-gravity engines nor is there likely to be. Chemical rockets are going to be around a long time. Probably so, but that doesn't mean that chemical rockets are in a state of perfection which permits no major improvements. Too much of the accepted wisdom in chemical rocketry is just the first thing that happened to work when people were in a hurry in the 1950s. The alternatives are poorly explored, and the current technology is in no way optimum. I think we've progressed a bit beyond kerosene and LOX, but there are probably further improvements possible. Also, "nor is there likely to be" is gross hubris. If you added "soon" to that, I might agree, with reservations. While just about anything is possible, I highly doubt there will be anything to replace chemical rockets (for launch from the Earth) ever. I give it zero probability in the next 50 years. I hope I'm wrong since there is nothing I would like more than to hop into my space flitter and have a hamburger at the cafe on the Phobos, but I don't believe it will happen. No economies of scale and highly unlikely space craft will ever be mass produced like Toyotas. There won't be mass production of spacecraft without major improvements in propulsion, which probably won't happen soon. But there is plenty of room for somewhat lesser economies of scale. Having reusable spaceships merely cost as much as major airliners would be a massive improvement... and there is no clear reason why they couldn't, since they should actually be simpler. Lesser by a great factor. Successful aircraft are produced in numbers far exceeding the number of spacecraft anyone would want (assuming no one invents dilithium crystals). The closest comparison available is the Concorde, which was a commercial disaster and never recovered the development costs. Further, if spacecraft became flyable by entities other than governments, which are for the most part exempt from their own regulations, the regulatory burden to certify the airframe for flight would run the cost right back up and they would hardly be simpler as they would have to be certified for both atmospheric and space flight. One needs only to look at the time and cost required for certification of a new, simple, piston engine driven aircraft to get a feel for this. Since it is so expensive, only governments can afford to do it... An increasing fraction of space launches are for private customers, and there have already been privately-developed space launchers (a few). The vast majority of "private" space launches use government vehicles. There is yet to be a Orbits-B-Us private launcher that; A) Works B) Has significant cost savings If there were, every satellite maker on the planet would be beating on their door. If you assume that development of a reusable spaceship has to cost billions and billions, then definitely only government can do it. But that is an assumption, not a self-evident fact. Without dilithium crystals, it IS a self-evident fact. We've had space flight for about half the time we've had flight, and the best we can do is a few individuals with one off designs that at best will get a person or two up and back just to set a record that cost millions. The basic laws of economics prevail; if it were possible, someone other than the government would be putting satellites in orbit and making a buck or two in the process. That's not to say costs can't be reduced, just that it is unrealistic to expect a couple of orders of magnitude reductions. I would say that a more accurate statement is that it is difficult to *prove* that such a reduction is possible. The notion is not ridiculous; even high-performance experimental aircraft typically operate at only perhaps ten times their fuel costs... and that is *several* orders of magnitude better than today's rockets. There is no obvious law of nature which prevents reusable rockets from getting down into the same range. No law of nature, but law of governments. Are you aware that the Wright recreation had to get special exemptions from the FAA to take place? If the current regulatory burden were in place at the time of the Wright's original flight, we would still be flying spruce and linen biplanes. -- MOST launched 30 June; science observations running | Henry Spencer since Oct; first surprises seen; papers pending. | -- Jim Pennino Remove -spam-sux to reply. |
#76
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Hubble Question...
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#77
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Hubble Question...
In rec.radio.amateur.space John Doe wrote:
wrote: No major advances in basic propulsion science, i.e. no dilithium crystals, impulse drive or anti-gravity engines nor is there likely to be. Until 2053 :-) (for warp drive, the rest will be transfered technologies from Vulcans) That's not to say costs can't be reduced, just that it is unrealistic to expect a couple of orders of magnitude reductions. I agree entirely. However, this brings a big dilemma: does one adopt a defeatist attitude and stop looking for new and improved propulsion methods limiting humanity to current rocket engines for the foreseable future, or does one continue to research new propultion methods with failures until they actually come up with something that works ? One continues to refine and improve methods that conform to known physics and hope that sometime, somewhere, someone in a lab says to himself "Gee, that's weird" and comes up with something new. How many rockets exploded/failed in the 50s and 60s until they got it "right ?" (heck, Ariane has had a lot of recent explosions). How many airplanes crashed until they got it "right"? The US has had what, 3 spacecraft accidents where life was lost? The engine isn't the only story. Thermal protection is another big issue. What seems to be stopping NASA right now is a religious choice between a reusable vehicle and a simple capsule, and for reusable, whether it should be winged or not, parachute or not. What seems to be stopping NASA right now is the choice between a non EPA approved foam that works and an EPA approved foam that doesn't work. -- Jim Pennino Remove -spam-sux to reply. |
#78
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Hubble Question...
What seems to be stopping NASA right now is a religious choice between a reusable vehicle and a simple capsule, and for reusable, whether it should be winged or not, parachute or not. What they should do is pick the capsule, low tech well understood, minimum cost and get it operational on top of a expendable. While studying everything else. Once a better lower cost more desieerable launcher comes along then migrate from the capsule design to the new one. Spend too much more time studying this and if theres another shuttle lost we might have no manned launcher untill something new is finally built. Besides which the capsule design may get us out of LEO a great thing. |
#80
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Hubble Question...
[In other words - the foam that was the root cause wasn't changed, and the foam that was changed merely led the events to occur earlier rather than start occuring. They were Yeah but just recently they decided the eroot cause was liquified air in voids from the low temperatures or something like that. |
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