en-us http://www.thespacereview.com/article/1945/1 Comments from The Space Review: An American fable http://www.thespacereview.com/article/1945/1#IDComment207122816To hell with the big, fragile fuel tank. Just recover the engines and avionics. Thu, 13 Oct 2011 21:54:18 +0000http://www.thespacereview.com/article/1945/1#IDComment207122816 http://www.thespacereview.com/article/1945/1#IDComment206976091People who say things can't be done are mere irritations to the people who are doing them. Thu, 13 Oct 2011 15:44:34 +0000http://www.thespacereview.com/article/1945/1#IDComment206976091 http://www.thespacereview.com/article/1945/1#IDComment206697386The Falcon reusable concept is improbable for many reasons (listed upthread), but perhaps it is a cover for something else. Some of the technologies "overtly" for resuable launch vehicles could well be applied more profitably to upgraded vehicles like Falcon 9 Heavy or future "Falcon X" rockets to increase reliability and lower costs, while competitors are flummoxed by the "reusable" program. As for Mars, there are two reasons for SpaceX to focus on that goal. 1. This is recognizable to most potential investors and supporters, who are less likely to see the value of an asteroid or NEO mission 2. If you have the ability to go to Mars and return, you have or are close to having the ability to go the asteroids and NEO's anyway. I think Elon Musk is being as smart as a fox. Wed, 12 Oct 2011 23:33:24 +0000http://www.thespacereview.com/article/1945/1#IDComment206697386 http://www.thespacereview.com/article/1945/1#IDComment206602216I just wish that SpaceX would mate the Falcon 9 to the Boeing's X-37B or better the X-37C. The X-37B is already in use and its weight is with the ability of the Falcon 9 to deliver to orbit. They should continue with the Dragon of course because multiple revenue streams are always important. Wed, 12 Oct 2011 18:56:03 +0000http://www.thespacereview.com/article/1945/1#IDComment206602216 http://www.thespacereview.com/article/1945/1#IDComment206585272I wish more people would quote Iron Maiden. "What became of the men that started / all are gone, and their souls departed / left me here in this place, so all alone / STRANGER IN A STRANGE LAND" Wed, 12 Oct 2011 18:03:16 +0000http://www.thespacereview.com/article/1945/1#IDComment206585272 http://www.thespacereview.com/article/1945/1#IDComment206105231Well, at least it ain't Skylon! :-) I can see how complex an effort this is, and Musk is right to say it's going to be hard. I assume they won't try to do the whole package at once for operational purposes. Question is: which should be first: the first stage, or the Dragon? I would go with the Dragon. The second stage was designed for recovery way back when, but with a different flight profile in mind. The problem I have is with the stability of the first stage on descent: it's tall and skinny, and looks like it will topple over. I wonder if they aren't pushing beyond the limits of the design constraints of what is essentially, a classic expendable vehicle. A squat vehicle with landing gear anchored further up on the body of the stage would make more sense; that's one reason why the Dragon landing profile is actually the most feasible of the three components. But that's just me. Tue, 11 Oct 2011 18:48:46 +0000http://www.thespacereview.com/article/1945/1#IDComment206105231 http://www.thespacereview.com/article/1945/1#IDComment20603140230 years of space shuttle operating experience has shown one thing for sure: chasing the illusion of RLV cost effectiveness is an excellent way to throw gobs of money down a rathole. SpaceX should keep its eye on the prize and get all the manufacturing cost possible out of the Falcon 9 ELV engines, tanks and structure and reduce the turnaround time for the Dragon spacecraft as much as feasible with current technology (which is where reusability makes sense). Wasting a lot of time and money on figuring out how to return the 1st and 2nd stages of Falcon 9 for reuse is going to harm SpaceX by diverting the momentum it's achieved for the Falcon 9/Dragon launch system. Tue, 11 Oct 2011 15:17:54 +0000http://www.thespacereview.com/article/1945/1#IDComment206031402 http://www.thespacereview.com/article/1945/1#IDComment205993745I have a naive question, why doesn't NASA try to develop a launch loop? According to Wikipedia it would only be 40 billion dollars? Does anybody know why this idea isn't more popular? Tue, 11 Oct 2011 13:18:48 +0000http://www.thespacereview.com/article/1945/1#IDComment205993745 http://www.thespacereview.com/article/1945/1#IDComment205933753Elon Musk is a genius and a visionary and one of my most admired people. I'm a science fiction buff of 50 years. In the great early science fiction movies, private companies mounted the big space explorations like trips to the moon and Mars. Finally Elon is making this a reality!!!! Tue, 11 Oct 2011 09:56:14 +0000http://www.thespacereview.com/article/1945/1#IDComment205933753 http://www.thespacereview.com/article/1945/1#IDComment205891248Should their not be a law in the United States, indeed in all countries, a law that forbids people ,industries and R&D institutions from placing in the public domain, namely, in newapapers , magazines and the media in general, such claims of miraculous advances in science and technologies, and unbelievable commercial and economic success that might arise thereform to benefit socitey? Without prior publication in reputed and accredited scientific and technical journals that will not publish such claims without expert peer review,should not such claims be forbidden by law? Tue, 11 Oct 2011 07:16:33 +0000http://www.thespacereview.com/article/1945/1#IDComment205891248 http://www.thespacereview.com/article/1945/1#IDComment205820740The true scale of SpaceX's cost reduction should be against the $1.5 billion cost per Space Shuttle flight... Current Falcon cost is $80 million... about 20 times less than NASA's shuttle which has been bleeding the US space effort for decades. A further reduction to $8 million would be a 200 x improvement over NASA's shuttle... Second, there is little history of reusable rocket engines because either they were launched and lost as non-reusable, or in the case of the shuttle, our Fed Agency NASA could care less how much taxpayer$s was wasted... Thirdly, I point out that what SpaceX has done or proposed could have been done 30+ years ago.... rather than the $500 billion wasted on a dead-end bankrupting space shuttle, useless space station, and failed/canceled Constellation... Private enterprise like SpaceX is a hope to free us from the 40 years of NASA dead wood non-progress. Tue, 11 Oct 2011 02:56:06 +0000http://www.thespacereview.com/article/1945/1#IDComment205820740 http://www.thespacereview.com/article/1945/1#IDComment205800090This is perhaps the best article I have read on the subject. Thanks Stewart. One oversight (unless I missed it) is that there was no mention of the large manifest of future launches which increases SpaceX's chance of success significantly. Tue, 11 Oct 2011 01:54:36 +0000http://www.thespacereview.com/article/1945/1#IDComment205800090 http://www.thespacereview.com/article/1945/1#IDComment205782364Excellent article! Tue, 11 Oct 2011 00:52:18 +0000http://www.thespacereview.com/article/1945/1#IDComment205782364 http://www.thespacereview.com/article/1945/1#IDComment205712214Elon's being totally above board about the difficulty. Will be very nice to see some clever solutions to the very real & tough problems with reusability. However a logical source of raw materials in LEO is orbited upper stages, which normally just deorbit in a hurry because of drag. Capturing and "tank-farming" all those second stages could provide an important resource stream for a Solar Power Satellite construction effort - as suggested a few years ago at an ISDC (IIRC), so your suggestion Stewart could be one option that SpaceX is exploring. All the criticisms by other commenters should also be the *start* of their effort, and not the end. They've identified problems. Good. Now start imagining the solutions... the actual hard work of making the Dream become Real. Mon, 10 Oct 2011 21:19:39 +0000http://www.thespacereview.com/article/1945/1#IDComment205712214 http://www.thespacereview.com/article/1945/1#IDComment205708422Thank you for a very interesting article. - Elon Musk and SpaceX deserve our support all the way! Mon, 10 Oct 2011 21:07:45 +0000http://www.thespacereview.com/article/1945/1#IDComment205708422 http://www.thespacereview.com/article/1945/1#IDComment205690512For comparison read Michael Flynn's 1996 novel "Firestar". The reason the protagonist has her rockets built is different, but the process is very similar. Come to think of it Elon Musk may have read it already. The book is a good read, and once done with it try "Rogue Star", "Lodestar", and "Falling Stars". Mon, 10 Oct 2011 20:19:05 +0000http://www.thespacereview.com/article/1945/1#IDComment205690512 http://www.thespacereview.com/article/1945/1#IDComment205689519. yes, it's a "fable" because can't happen . there's no doubt that "reusability" is the key word for a cheaper access to Space, but ... the SpaceX presentation is 99% marketing and only 1% reality, because ... . first of all, the price of each launch NEVER can be ONLY the price of the propellants, since, also assuming the 100-launches-per-rocket claimed by Musk, we must add the shared cost of the rocket: $65 million / 100 flights = $650,000 + $200,000 for the propellants = $850,000 per launch . then, assuming all flights goes well and all rocket stages come back undamaged, we must add the refurbishing, testing, intergration, refueling, launch, etc. costs of the next launch, that could be in the range of $500,000 to $2,000,000 . also, we must add the shared R&D costs on, at least, the first 100 launches (that need YEARS to be accomplished) so, if we evaluate that costs in the range of $300-500 million (due to the much more complex challenges of a reusable rocket) we must add a further $3-5 million per launch, on the first 100 launches . so, the total cost per launch (so far) of a "reusable Falcon-9" is in the range of $5-8 million, that put the payload price-per-ton to LEO at around 8-12 times less than the price of an expendable Falcon-9 and NOT 1/100th of the price! . but, all these evaluations, are valid and correct ONLY assuming that a Merlin engine (that, despite it's much cheaper than all other old.space engines, covers great part of the Falcon-9 costs) can be safely and reliably used up to 100 TIMES, that sound only a sci-fi hope, since, unfortunately, NO ONE rocket engine, so far, has survived the stress and high temperatures of more than two-three burnings . also the SSME that is VERY expensive and designed from scratch to be reusable, ISN'T REALLY SO MUCH REUSABLE, since, its average reuse (before severe and dangerous damages and ablation) has been of about 10-15 launches per engine, so, the Merlin, that wasn't born to be reusable, should probably be replaced after 3-5 launches, that, also since three of the nine engines must work twice per launch, for lift-off and landing . last, don't forget that all the hardware added to a standard Falcon-9 to turn it to a reusable rocket (1st and 2nd stages landing pad, extra-propellants for landings of the two stages, an heavy thermal shield for the 2nd stage, etc.) do have a MASS and that extra-mass (especially the 2nd stage extra-mass) may CUT the 10 tons max payload carried to LEO by an expendable Falcon-9 to only 5-7 tons . well, if we consider all the extra-costs, extra-mass and extra-issues listed above, the REAL price-per-ton carried to LEO by a reusable Falcon-9 might be in the range of 20-30% the price of an expendable Falcon-9 and NOT (absolutely NOT) only 1% of today's costs!!!!!!! . in other words, an expendable Falcon-9 may cut the costs of the access to Space by a factor of 3-5 times, but absolutely NOT by a factor of 100 times and NOT EVEN by a factor of 10-20 times!!! . but, those listed so far, aren't the only problems to develop a reusable Falcon-9 because, first, SpaceX must find the FUNDS to develop, test and launch this kind of rocket, costs that may be found in two years or five years or seven years or never . then, assuming that SpaceX will find soon (within 2-3 years) the funds (in the range of $300-500 million) to develop a reusable Falcon-9 how much years may it need to be ready available for true and reliable launches??? (hoping, NOT with astronauts!) . well, evaluating 2-3 years from now to find the funds + 3-5 years to develop and test the rocket + 2-3 years to accomplish a good number of launches (to know its REAL reliability and operating costs) we can reasonably guess that its (modest) advantages could be get only by the end of this decade, or later . so, does it worth the efforts, time, costs to develop a reusable Falcon-9 ??? . my answer is "yes" anyway, but NOT hoping (nor falsely promising) that it may cut the costs of the access to Space by a factor of 100 because it's absolutely NOT TRUE . and, since I think that SpaceX and Musk perfectly know what I've just explained, it's clear that this bold announcement has only a marketing purpose, to find more funds, more investors, more supporters and more customers for their EXPENDABLE version of the Falcon-9 . the reusable Falcon-9 animation also has a BIG MISTAKE because, while the 2nd stage can be easily de-orbited at the right point to land at the KSC, the 1st stage, at stages' separation, isn't in orbit but at around 100 km. of altitude and 100-150 km. away from KSC and on top of the ocean, so, HOW the 1st stage can come back to the KSC without wings? and HOW MUCH propellants this operation will need? ... maybe, "magic?" ... :) . Mon, 10 Oct 2011 20:16:37 +0000http://www.thespacereview.com/article/1945/1#IDComment205689519 http://www.thespacereview.com/article/1945/1#IDComment205687622"As the United States settles in for the long winter ahead in American space launch capabilities," That statement is false. The US spacelaunch capability is more robust now than it ever was. Mon, 10 Oct 2011 20:12:03 +0000http://www.thespacereview.com/article/1945/1#IDComment205687622 http://www.thespacereview.com/article/1945/1#IDComment205685900I wish people, including Musk, would stop aiming at Mars. There's no there there; they're stuck in fantasies from pulp fiction and b-movie sci fi of the 1950s. The only value proposition at this time may be space-based solar or asteroid mining. If Musk aimed at staking a claim to the precious metals of an asteroid, focused on mining, refining and returning something of value to Earth to make a buck I would praise him. But instead he just sounds like another Martin Frobisher (look him up). Mon, 10 Oct 2011 20:07:59 +0000http://www.thespacereview.com/article/1945/1#IDComment205685900 http://www.thespacereview.com/article/1945/1#IDComment205653364"Muse, by the way, bills themselves as wanting to be the first band to play in space, so it’s not too hard to figure the royalties they are expecting from SpaceX. " ZZ Top made that claim 25 years ago. Mon, 10 Oct 2011 18:39:01 +0000http://www.thespacereview.com/article/1945/1#IDComment205653364