#11
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OSP requirements
"ed kyle" wrote in message om... With currently planned EELV launch rates averaging only 2 per year per vehicle and with neither EELV agressively competing for commercial launches, an all-new launch pad is the last thing NASA needs to pour money into, IMO. The EELV launch rate will go up. The current doldrums are just an interlude. Everything - a new pad (actually, two new pads - one Delta , one Atlas), modified pads, and modifying 39 are all on the table and being traded vigorously. When Shuttle is retired, NASA should scrap LC 39 to save money. Personally, I don't see 39 coming out on top in this. Making it - and the integration facility - compatible with two different vehicles is just such a complex engineering problem. -Kim- *my opinions, not my employers'* |
#12
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OSP requirements
"ed kyle" wrote in message om... "Kim Keller" wrote in message m... With currently planned EELV launch rates averaging only 2 per year per vehicle and with neither EELV agressively competing for commercial launches, an all-new launch pad is the last thing NASA needs to pour money into, IMO. When Shuttle is retired, NASA should scrap LC 39 to save money. If we use Delta and Atlas for supplying the station along with launching the OSP you add 10-25 launches a year. 15 rockets a year for each launcher would be a good jump start. |
#13
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OSP requirements
Dholmes wrote:
"Ian Woollard" wrote in message ... If this is so, it's still a win to make the vehicle smaller and simply launch more; since that's a 15% decrease in costs per doubling. However, I'm not as convinced that this 5-10% decrease is real. Do you have a reference to this scaling law? No just comparing rockets a different sizes but it appear consistent and logical. As I understand it, apart from minimum gauge and atmospheric drag, there's no definite reason why larger rockets should be cheaper per kg. However, there is likely to be an *apparent* decrease in cost with large rockets as they are invariably scaled up version of previous rockets. It's institutional learning, simply because it was version B; the organisation has learnt how to build rockets better. For example, that seems to be the case with Ariane V. There where actual design studies to create a module for the cargo bay that would have carried 75 people. Yes, but what happens if it crashes? It's bad enough when Columbia or Challenger crashed. If just one person dies, it's sad, but you don't get the great upswelling to anything like the same degree. 75 people is a different ballpark entirely. 75 people just isn't practical with the Shuttle; it's just not reliable enough; and by the time it could have launched enough to be made reliable, there would be several hundred dead. With a single person, you can have an escape tower. With 75, there's no chance of survival if there is a failure just after takeoff. People are much less concerned about single deaths, although it would be newsworthy. The market just is not there to support it. Only Soyuz have seriously tried, and they have found that there is a market. Interestingly a 6 man OSP would weight about 20 tons and require a heavy lift vehicle so it would really use three rockets. Half the number your 1 man plan uses. So even that increases volume of rockets just not launches. The OSP itself would be almost twice as expensive per person though. By way of contrast the cost of developing a small vehicle is proportionately lower, and you launch it much more often, so the amortised cost of the development is far lower. Consider that the far bigger Shuttle costs have never significantly amortised away; because it has not, and could not be, launched enough. |
#14
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OSP requirements
"Dholmes" wrote in message .. .
"ed kyle" wrote in message om... "Kim Keller" wrote in message m... With currently planned EELV launch rates averaging only 2 per year per vehicle and with neither EELV agressively competing for commercial launches, an all-new launch pad is the last thing NASA needs to pour money into, IMO. If we use Delta and Atlas for supplying the station along with launching the OSP you add 10-25 launches a year. 15 rockets a year for each launcher would be a good jump start. It would be, but I don't think we'll see it. Since 2000, inclusive, the combined total of all Atlas, Delta, Titan, and Shuttle launches have averaged 19.7 launches per year. Delta II will still be a going concern for awhile, apparently, and it accounted for 5.7 launches per year during the period. If we assume that STS flights stop and are replaced by EELV/OSP missions on a one-for-one basis, we are left with 14 launches per year. Even if you replace STS on a two-for-one basis (assuming one crew and one payload flight), the total comes to only 19.3 launches per year. The best case scenario, then, sees each EELV flying less than 10 times per year. Each rocket will have a pad on each coast, so the busiest pad will probably see no more than 7-8 launches per year. Existing Cape Canaveral EELV pad capacity is probably about 12 per year. Keep in mind that the Russians perform all of their manned and unmanned ISS support launches from a single launch pad. That pad (Baikonur Area 1) has hosted three Progress, one Soyuz, and the Mars Express mission so far this year. That's a rate of 7.5 launches per year - which is about what the busiest EELV pad will see. - Ed Kyle |
#15
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OSP requirements
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#16
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EELV launch cost (was: OSP requirements)
Brian Thorn wrote in message . ..
On 29 Aug 2003 12:45:58 -0700, (ed kyle) wrote: It would be, but I don't think we'll see it. Since 2000, inclusive, the combined total of all Atlas, Delta, Titan, and Shuttle launches have averaged 19.7 launches per year. True, but we are in a space launch doldrums of major proportions right now. Both the commercial comsat market and the military satellite launch pace have been markedly slower in the last four or five years, as ever-longer-lived satellites haven't needed to be replaced. But that won't be true too much longer. On the military horizon are Block IIF Navstars (33 satellites) currently scheduled for about one launch Navstar IIF and later DMSP 5D are manifested on Atlas V 401's and Delta IVM's. Navstar IIR and earlier DMSP 5D and TIROS-N have about the same mass as the later s/c and had Delta II or Titan II LV's. I saw a price quote of $75 million (on spaceflightnow.com) for the Delta IVM launnch of DSCS B6. IIRC, even a Delta II 7925 isn't price at $75 million. So, are we (the taxpayers) paying more for putting the later Navstar and DMSP on EELV's than on a Delta II? Or did the Air Force get a special deal with Boeing and LM on launches with lower mass s/c? If the latter is the case, then why isn't NASA getting the same deal for payloads like Phoenix, using an EELV, and ease design constraints on payload mass growth? Was the Delta IIH for Phoenix already bought and paid for? If Delta IVM and Atlas V 401 are really priced the same as a Delta II 7925, then Delta II s/b ending soon. Ok, there are the lower end 7320 launches, but the high end Taurus or Athena gets close to that capability and I would hazard a guess that they're also cheaper than a 7320. |
#17
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OSP requirements
"ed kyle" wrote in message om... OSP you add 10-25 launches a year. 15 rockets a year for each launcher would be a good jump start. It would be, but I don't think we'll see it. Since 2000, inclusive, the combined total of all Atlas, Delta, Titan, and Shuttle launches have averaged 19.7 launches per year. Delta II will still be a going concern for awhile, apparently, and it accounted for 5.7 launches per year during the period. If we assume that STS flights stop and are replaced by EELV/OSP missions on a one-for-one basis, we are left with 14 launches per year. Even if you replace STS on a two-for-one basis (assuming one crew and one payload flight), the total comes to only 19.3 launches per year. The best case scenario, then, sees each EELV flying less than 10 times per year. Each rocket will have a pad on each coast, so the busiest pad will probably see no more than 7-8 launches per year. Existing Cape Canaveral EELV pad capacity is probably about 12 per year. Delta II seems booked solid for the next several years. It has no direct competitor in its weight class the closest are 1/2 or twice its size. The only rocket that is even close is the Delta 4 Lite if it ever flies. It has been flying for years so all most of its costs have already been amortized. Of all the American rockets right now it seems the safest. A lot will depend on what method is chosen for shuttle replacement. One for one is not possible the shuttle carries seven people and 12.5 tons of cargo to ISS and 25 tons to LEO. The largest OSP I have seen is 5 people and less the 2 tons of cargo. On the small size is 3 people and less then 1 ton of cargo. You also need an ATV to send cargo, experiments and supplies. In total for 4 shuttle flights, less then the average number you need almost 6 of the large and 9+ of the small just for people. There would be some experiments that would need OSP launches as well about 1 large or 3 small. With an ATV you need to replace about 40 tons based on the lower figures. Basing this on the Eurpoean design you need a rocket capable of twice the cargo you want to deliver. You could get by with as few as 4 heavy launches or as many as 10 smaller ones. If as some have suggested you want to encourage the growth of the Delta 4 Lite to replace the Delta 2 then you could add as many as 10 additional flights. In reality you are talking about just under 3 to as many as 7 flights to replace a shuttle launch with 4 being the most likely. There are also 10 medium to heavy American rockets planned over the next year. So you have a minimum of 21 launches and a max of 32 while still flying one to two shuttle mission and absolutly no growth in the market. I could see 40 by 2010-2020. |
#18
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OSP requirements
"Dholmes" wrote in message news:
Delta II seems booked solid for the next several years. It has no direct competitor in its weight class the closest are 1/2 or twice its size. The only rocket that is even close is the Delta 4 Lite if it ever flies. The currently available Delta II series itself covers a 2X payload mass range, i.e., a 7920H has twice the capability of a 7320. The proposed LM Athena 3 was close to 7320 capability, but it's only a paper rocket now. There were some posts recently about refurbishing additional Titan 2 ICBM's which would also cover the 7320 capability. So there *could* be more than one bidder for new NASA Med-Lite launch services. Tsyklon, Russian ex-ICBM's, and Vega (which is just paper at this point) also fit in the range, but they're outside of the US. I am not sure about this, but it appears to me that Navstar IIF and DMSP 5D could have used 7925 for launch. Instead, they are using EELV's. An EELV program goal was to reduce launch cost to less than 50% of heritage LV's, so maybe they have reached that goal and a Delta 4M or Atlas V 401 is as cheap to buy as a 7925. That would allow phasing out the Delta II 7900 LV's. |
#19
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OSP requirements
On Fri, 29 Aug 2003 09:56:17 GMT, "Dholmes"
wrote: Interestingly a 6 man OSP would weight about 20 tons and require a heavy lift vehicle so it would really use three rockets. I think you're over by a factor of two. the Apollo capsule (13,000 lbs) was rated for five crew (SkyLab rescue) six was easily possible, and nine was an option if they really worked hard at reconfiguring the cabin. A Service Module for ISS transport will weigh much less than 30,000 lbs. I don't see a capsule OSP variant for six crew being anywhere near 20 tons. Brian |
#20
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OSP requirements
Dholmes wrote:
"Bob Martin" wrote in message ... I'm interested in seeing what you guys would come up with if you were writing the requirements for the OSP. Any takers? I am kind of torn between large and small. A simple capsule would require over a dozen launches a year giving some needed volume. A larger space plane would need only 3 or 4 launches a year but help to develop heavy lift. A capsule should be both cheap and quick to develop. A large space plane while more expensive to develop has better follow on when a reusable first stage is developed. Most of those questions are the same ones we asked at the beginning of shuttle development. We ended up settling for a system that was (allegedly) cheaper to develop, but more expensive to operate. Not that NASA didn't want the TSTO all flyback stage designs that would have been the reverse, but it soon became clear that Congress wouldn't pony up the higher up-front costs, and there was much controversy over what the expected traffic models were most realistic. The more traffic to orbit you expect, the more a vehicle with lower operating costs (in spite of higher development costs) make sense. However, one of the opposing arguments was that a Mars mission would be one of the projects for which this shuttle would be used for (NASA would still be only user, after all), and this was a way of pulling the rug from beneath the idea. Similarly, you have to ask what an OSP will be used for. Mostly ISS servicing? Do you dare suggest it might have the capacity of also supporting another large manned project? (Moon/Mars/Near Earth Asteroid, take your pick) Some people still don't want to hear that.... And are its payload capacity (volume and weight) and operating costs such that there might be a commercial interest? NASA has long said it wants a vehicle that is a convergence of the two. Others say (and I'm strongly inclined to agree) that the needs are so different that such a one-size-fits-all convergence may not be possible. |
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