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#501
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Andre Lieven wrote:
"Jake McGuire" ) writes: Andre Lieven wrote: Those who have been spolied by post WW2 rates of technological progress ( And, who ignore fields where such progress has not been long term forward- commercial air travel, for instance: 1962: 560 MPH. 1978: 1,250 MPH. 2005: 580 MPH. ), fail the test of history. Wrong figure of merit. Why ? You make no case, so theres nothing to refute. The case is that technological progress in commercial air transport has not been in the area of top speed, because relatively few people care, or care enough to pay for it. Then, you're unaware of the history of commercial avaition, and its becomming popularly available and useful when, among other things, its speed had reached the 500-600 MPH region, for long haul flights. And you, in your shallow analysis, jumped all over the 500-600 mph thing, and effectively said "That's that." That's not it. The air travel revolution that occurred with the introduction of the American jetliners in the late '50s wasn't so much a question of speed, (Although that was a factor) but availability. A DC-7 or Constellation made an Atlantic crossing in, on a good day, 10-12 hours, depending on whether it had to fuel in Gander for the trip across. But - once it arrived at its destination, the 4 extremely complicated recips needed roughly another 10-12 hours of TLC to have them ready for the next trip. (Spark plug changes, carb recalibration, etc.) While the engines themselves were reasonably reliable (Time Before Overhaul was in the 2,000-2,500 Hr range) and were rather efficient (Specific Fuel Consumption at cruise could be reasonably considered to be 0.35 lbs fuel/HP/Hr ), reciprocating engines had reached the point where the complication to achieve that efficiency was a detriment. The early jets started out with similar expectations of engine life. And they burned a lot more fuel per flight hour. But - it was discovered early on, that all you needed to do to turn around a jet airliner was fill the tanks, sweep it out, and put aboard a rested crew. Where a DC-7 of L.1649 could manage a one-way crossing per 24 Hr day, the jets started with 2 crossings per day. Then the engine TBOs increased dramatically - even before the expected 2500 TBO dates occurred the time was raised to 5,000, and then more than 10,000 Hrs. This meant that years passed before the need for an overhaul. What made the operating economics of jets work was the fact that you could keep them in revenue service from the first time you pushed back from the gate until it was due to go into the shop. And they could do it repeatedly. With a recip, the scheduled arrival time was more of a guideline - weather en route, or at the intermediate stops, or an engine problem cropping up at an intermidiate stop would stall things for hours, sometime days. With the jets, a businessman in New York could be fairly certain that they'd be in London or Paris the next day. And, I dare say that were flights to the Uk, say, from Eastern N. America matters of 16-20 hours of flight, they might not be as popular... It's not speed, per se - experience has shown that being able to get to Europe from North America within the same day is fast enough for commerce. The extra costs of flying faster won't be attractive enough no matter what. The Concorde's replacement for hurried, ultra-rich business travellers is the Citation X, which perks along at Mach 0.92, and not the various Ted Smith/Sweringen/MiG/Sukhoi paper supersonic Bizjets. Well, that, and teleconferencing. Rather, the progress has been in making airplanes cheaper to operate through reduced maintenance costs, fuel burn, crew size, and increased reliability. And in these areas, the progress has been immense. College students can fly (!) to Europe (!) Kinda hard to do that on a 250 MPH bird... But it also doesn't happen with a 1200 mph bird. with the money they make slinging tacos, for god's sake. Indeed, and that would be harder if aircraft needed twice as much time, per mile and flight. Higher costs, and all... An yet, it hasn't made any economic sense to go faster. Try "Price of JFK-LHR round-trip ticket in constant-year dollars". Well, by that standard, the whole modern auto industry might as well close up shop, as no one from 1903 can afford a modern car... Nonsense. The Model T came on the market at $850, or about $16k in 2005 dollars. Thats an interesting calculation of nearly a century's worth of inflation. Care to post then V/ now average US yearly incomes ? Annual income of a farm family at the turn of the Century was generally between 500-800 dollars, and didn't increase much beyond that until World War 2. A Model T represented a year's worth of income. My co-worker just bought a Chevrolet Aveo for $8k 2005 dollars. Compared to the Model T, the Aveo is stupendously luxurious, amazingly powerful, has a ride like a magic carpet, and so protective it practically comes with a built-in guardian angel. None of which answers the point of relative affordability of cars then V/ now... I don't think the Aveo is costing a year's pay. -- Pete Stickney Java Man knew nothing about coffee. |
#502
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![]() "Jeff Findley" wrote in message ... "Scott Lowther" wrote in message ... Jeff Findley wrote: Because the American public, in general, doesn't care about manned spaceflight. More people are likely aware about how high the oil industries profits were last quarter than are aware of how many people are on ISS at this moment. You confuse ISS with manned spaceflight. It's manned going-around-in-a-circle. At the moment, shuttle/ISS *is* US manned spaceflight, and the US public isn't interested. If you look back at Apollo, public interest was dropping like a stone once Apollo 11 made it home safely. Only the chance of astronauts dying in space made the public wake up during Apollo 13. The same thing will happen with Apollo 2.0. After a couple of missions, the public will quickly lose interest. Not if they figure out how to package it as a reality show ![]() |
#503
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![]() Pat Flannery wrote: Alain Fournier wrote: I don't think that was direct trade though; they'd trade with a tribe who would trade with another tribe, who would....and soon, you'd have materials thousands of miles from their point of origin. They would (and still do) come from quite far away to meet in pow-wows Yeah, but pre-horse, "quite far away" would probably mean 100 miles at most. When your prime means of movement are foot and dog trellis you move at around 3 mph tops, and that doesn't include sleep or eating, which are going to take around half the day. So a journey of 100 miles is going to take around 60 hours, and you can extrapolate from there. At some point the amount of food you are going to have to carry with you (you'll be able to supplement it some on the way via hunting and gathering, but you wouldn't want to count on it) is going to get excessive. If you are hunting and gathering at home it doesn't make much difference doing it on the road, so yes you can count on that for your food. Pre-horse, travel wasn't limited to walking. Canoes are quite old. It doesn't go faster than walking (faster going down the river slower going up) but you can carry heavier loads, which is important if you want to trade. The big pow-wows were held about once a decade, and they could take months to get there, they did travel from quite far away, but ... (see below) After the horse arrived on the scene, maybe 300 miles at most. We had a meeting site for tribes here in Jamestown at the junction of the James and Pipestem rivers- I get the feeling that most of the tribes that met here came from a radius of around 100 miles, if even that. I remember learning the information I wrote above at the National Museum of Civilization in Ottawa. I think, I remember that those pow-wows were held pre-Columbus but I'm not sure about the time frame. Maybe the big ones were only after the introduction of the horse. Alain Fournier |
#504
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On Sun, 20 Nov 2005 16:20:51 -0600, Pat Flannery
wrote: Yeah, but pre-horse, "quite far away" would probably mean 100 miles at most. ....More like 40-50 miles, and that's only if horses were about as half as widely available as, say, cars are today. And again, that's only if you factor in the terrain between the two points; the more habitable, the easier to traverse without having to bring along your own provisions. OM -- ]=======================================[ OMBlog - http://www.io.com/~o_m/omworld Let's face it: Sometimes you *need* an obnoxious opinion in your day! ]=======================================[ |
#505
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On Sun, 20 Nov 2005 17:45:05 GMT, "Greg D. Moore \(Strider\)"
wrote: So I will end the discussion here. ....Considering he used his illegal cliche' - which months ago was declared to render any and all of his arguements automatically null and void when used - this is the correct move. The next move is to do what many of us have already done - sent him to the Canucklefrog wing of Killfile Hell. OM -- ]=======================================[ OMBlog - http://www.io.com/~o_m/omworld Let's face it: Sometimes you *need* an obnoxious opinion in your day! ]=======================================[ |
#506
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On 19 Nov 2005 17:57:10 -0800, "Jake McGuire"
wrote: I'm more concerned with increasing both my understanding and the collective understanding of sci.space.policy than in scoring rhetorical points. Q: Name one modern-day equivalent of Don Quixote's efforts against windmills? A: Understanding .policy. OM -- ]=======================================[ OMBlog - http://www.io.com/~o_m/omworld Let's face it: Sometimes you *need* an obnoxious opinion in your day! ]=======================================[ |
#507
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On Sat, 19 Nov 2005 23:19:01 GMT, "Greg D. Moore \(Strider\)"
wrote: Ibid. It appears you don't know how to use that word correctly. ....No, actually, he did. Provided you use the acronym definition: "I Be Ignorant Dip****" OM -- ]=======================================[ OMBlog - http://www.io.com/~o_m/omworld Let's face it: Sometimes you *need* an obnoxious opinion in your day! ]=======================================[ |
#508
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![]() Rand Simberg wrote: On 10 Nov 2005 13:12:06 -0800, in a place far, far away, " made the phosphor on my monitor glow in such a way as to indicate that: snidely wrote: No, no, Scott -- this is the core of what you have wrong. The public doesn't care a fig about HERO-ASTRONAUTS unless there is a hint of blood and gore (a bit like NASCAR). What VG, XCOR, Bigelow are selling is PERSONAL SPACE TRAVEL, and quite a few more people are interested in that. Here's your problem: the public tends to identify more with astronauts than bajillionaires. What difference does it make whether or not the public identifies with bajillionaires? Simple: the claim here was that people don't care about astronauts, they care about "personal space travel." "PST" is all about bajillionaires, and will be for a while. But astronauts... people like. |
#509
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![]() Rand Simberg wrote: On Fri, 11 Nov 2005 13:51:03 GMT, in a place far, far away, Scott Lowther made the phosphor on my monitor glow in such a way as to indicate that: No profit, but there are tangible benefits to maintaining a viable US Air Force. And you think there woudl be no benefits to maintaining a permanent lunar presence or manned missiosn to Mars? None worth the high cost of this architecture, given the trivial amount of activity that it will allow us to afford. Landing twenty or more times as much stuff on the lunar surface than a Saturn/Apollo could do at less cost... and in fact at no great increase in the NASA budget over the current do-nothing Shuttle, sounds pretty damned good to me. |
#510
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![]() Rand Simberg wrote: On 10 Nov 2005 09:21:03 -0800, in a place far, far away, " made the phosphor on my monitor glow in such a way as to indicate that: What's need now is not an improvement in performance - which comes from giant research programs - but improvements in cost, reliability and maintainability... which comes from *experience.* Which won't come from flying giant vehicles two or three times a year. Really? Well, then perhaps we should fly the HLLV a dozen times per year instead. Still, 2-3 times per year is substantially better'n Shuttle, so... Plus, the HLLV will help set up places for the DinkyRockets to go to. Single launch space stations, a lunar base in one or two shots, you name it. |
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