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Elon Musk's SpaceX to build 'Grasshopper' hover-rocket
In sci.space.policy message
, Mon, 10 Oct 2011 19:00:54, Brian Thorn posted: On Mon, 10 Oct 2011 16:12:45 +0100, Dr J R Stockton wrote: The US Government seems more likely to go broke than the telecoms industry. No, it isn't. Ask Iridium about that, which went broke and was bailed out by the government (DoD). Teledesic had a contract for lots of Delta III launches, too. They went kaput. Iridium was only a small part of the telecoms industry, most of which is not even in the United States. But the USA has just the one Federal Government. The USG is quite capable of following where the Greeks are leading. But I am not considering ISS or polar missions. The problem is that the market simply isn't big enough to justify a GEO-bound-only launch site. With the big satellites lasting well over a decade and costing hundreds of millions of dollars each, replacement launches are few and far between. Having a 50% cheaper launcher is not going to create double or triple the demand for GEO comsats. And would SpaceX be able to reach 50% cheaper while paying for all new launch infrastructure/processing/range at South Padre Island, or an aircraft carrier in the Atlantic? Mr. Musk is good, but he's not *that* good. Judging by his ability to build rockets, he should be able to build and operate launch sites for 10% of what a NASA site would cost. In effect, he's doing that already at CCAFS. BTW, I checked the North Shore of the Gulf of Mexico in Google Maps. A lot of wildlife refuges, but not continuous. A lot of residential, but not continuous. In between, unused shore-land. Given the size of Falcon 1 (one), and noting that there is a railway line beside his works, ISTM a pity that (AFAIK) he didn't get it to launch from a train. -- (c) John Stockton, nr London, UK. Turnpike v6.05 MIME. Web http://www.merlyn.demon.co.uk/ - FAQqish topics, acronyms and links; Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm, etc. No Encoding. Quotes before replies. Snip well. Write clearly. Don't Mail News. |
#52
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Elon Musk's SpaceX to build 'Grasshopper' hover-rocket
Brian Thorn wrote:
No, it isn't. Ask Iridium about that, which went broke and was bailed out by the government (DoD). I thought that Iridium went through a "proper" bankruptcy and that the folks who picked-up the assets on the cheap were then able to sustain operations based in no small part on contracts with the U.S. Government? http://en.wikipedia.org/wiki/Iridium...ations#History rick jones -- oxymoron n, Hummer H2 with California Save Our Coasts and Oceans plates these opinions are mine, all mine; HP might not want them anyway... feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH... |
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Elon Musk's SpaceX to build 'Grasshopper' hover-rocket
On Wed, 12 Oct 2011 23:33:07 +0100, Dr J R Stockton
wrote: Iridium was only a small part of the telecoms industry, most of which is not even in the United States. But the USA has just the one Federal Government. The USG is quite capable of following where the Greeks are leading. Perhaps, but in that case we're talking an economic calamity that dwarfs the Great Depression. I don't see the telecom industry remaining particularly strong in such an event. Judging by his ability to build rockets, he should be able to build and operate launch sites for 10% of what a NASA site would cost. In effect, he's doing that already at CCAFS. No, he really isn't. He's paying to use the existing Cape infrastructure, especially power, communications, tracking range and payload processing facilities. And his pad is one of the two old Titan IV pads, so he didn't start from scratch like he'll have to do elsewhere. The same is true at Vandenberg, by the way, where he is again using an old Titan pad. Starting over in Texas is going to be considerably more expensive. Brian |
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Elon Musk's SpaceX to build 'Grasshopper' hover-rocket
On Oct 12, 4:52*pm, Brian Thorn wrote:
No, he really isn't. He's paying to use the existing Cape infrastructure, especially power, communications, tracking range and payload processing facilities. And his pad is one of the two old Titan IV pads, so he didn't start from scratch like he'll have to do elsewhere. The same is true at Vandenberg, by the way, where he is again using an old Titan pad. Starting over in Texas is going to be considerably more expensive. And that's not the only existing infrastructure Musk is making use of. The test firings of the Falcon 9 stages were all conducted using what remained of defunct Beal Aerospace's old test stands and facilities in McGregor, Texas, which were originally intended for the never-built BA-2 rocket. So if Musk had to build all that on his own, not simply buy up and modify someone else's, he'd have had to spend much more, and take more time than he already has. -Mike |
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Elon Musk's SpaceX to build 'Grasshopper' hover-rocket
On Oct 2, 7:17*pm, Robert Clark wrote:
*A couple of suggestions for the reusable version of the Falcon 9. First, model it on the DC-X. In the SpaceX video of the proposed reusable launcher the first and second stages have the same straight sides of the expendable versions. But having sloping sides helps to protect the sides of the vehicle during reentry as well as increasing aerodynamic stability during reentry. Note that as long as the cross-section remains circular for a conical shaped stage you should still get the high tankage ratio that obtains for cylindrical tanks: ... The second model for the reusable Falcon 9 stages would be on the ESA's proposed Intermediate eXperimental Vehicle (IXV): Article: Europe Aims to Launch Robotic Mini-Shuttle By 2020. Rob Coppinger, SPACE.com ContributorDate: 13 June 2011 Time: 02:58 PM EThttp://www.space.com/11948-robot-spa...hing-2020.html This does not use the powered landing of the DC-X but rather uses a glided landing via its lifting body shape. SpaceX does not like the use of wings for landing because of the extra weight. But this design would not have wings. It would have larger thermal protection weight because the horizontal underside would have to be covered, whereas in the DC-X mode only the base has to be covered. However, it would make up for this in not requiring fuel for the powered landing. In this case because the stages would have to maintain the aerodynamic shape, they could not be stacked as for serial staging. Parallel staging would have to be used. Once again this means the separate stages could be used as SSTO's. Another possible lifting-body shape for reusable Falcon 9 stages might be of the Japanese HYFLEX hypersonic test vehicle: Hypersonic Flight Experiment "HYFLEX". http://www.jaxa.jp/projects/rockets/hyflex/index_e.html HYFLEX. http://www.rocket.jaxa.jp/fstrc/0c02.html This was successfully tested all the way back in 1996 at a Mach 15 reentry speed. It's roughly cylindrical shape would mean you would lose a relatively small degree on the mass efficiency of cylindrically shaped tanks. However, rather than redesigning the tanks you might want to just use a composite aeroshell on the usual Falcon 9 stages. A conical aeroshell for example was used on the DC-X. This would make the reusable Falcon 9 more quickly and easily to be implemented. The mass of the aeroshell though would contribute to the mass lost from payload. As with the above cases, if used with altitude compensating nozzles on the Merlins or with existing high efficiency engines with just their standard nozzles, these HYFLEX-shaped stages could also be SSTO's. Bob Clark |
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Elon Musk's SpaceX to build 'Grasshopper' hover-rocket
On Oct 3, 6:26*pm, Dr J R Stockton
wrote: ... launch from the Texas coast, ... Some here disliked that idea. It appears (as I thought at the time) that Elon Musk does not. See for example http://spaceflightnow.com/news/n1111/18spacexlaunchsite/. Better, though, to buy an island in the Mouths of the Amazon; or to rent space in CSG (E.M. no would probably appreciate the cooking better there). -- (c) John Stockton, near London, UK. Using Google, no spell-check. Mail: or (better) via Home Page at Web: http://www.merlyn.demon.co.uk/ FAQish topics, acronyms, links, etc.; Date, Pascal, JavaScript, ....| |
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