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#31
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Space X 2nd stage recovery
David Spain wrote on Wed, 25 Apr 2018 10:51:25
-0400: On 4/24/2018 4:36 PM, JF Mezei wrote: On 2018-04-24 14:21, David Spain wrote: I am of the opinion that the existing F9 and F9H architectures will be (crew-wise) underutilized. Unless the space station life is extended beyond 2025, FH and Dragon2 may very well remain the workhorse for mnanned space in USA. Well you and I have somewhat different opinions of workhorses. Ferry flights to ISS are all well and good. But unless an expansion of ISS in in the works a flight rate of what, about 4 flights a year is more than sufficient? Barring commercialization of ISS (which may or may not happen) and/or some orbital 'hotels', neither Dragon V2 nor CST-100 have a real future. They are both LEO systems and if there are no LEO destinations they're toast. What about crewed LEO trips and/or Moon flybys for touristas? For that matter a crewed scientific flyby mission to Venus? Scouting missions to Martian moons even? Without a destination in LEO, I wouldn't expect a huge market for LEO trips. Falcon Heavy/Dragon V2 could do a Moon flyby with free return, but the bulk of that trip is going to be boring. You'll spend very little time near the Moon and the system doesn't have the capability to make that longer. That means the 'work horse for manned space flight will by default wind up being SLS/Orion, which massively sucks. And unless there is real funding for manned space programme beyond ISS, nobody will see much business case to invest in manned space programme from now on, unless you go for it on your own (aka: SpaceX with BFR to Mars). Funding by whom? We're just about at that point. Which is my point. Well, Blue Origin essentially has a billion dollar a year funding line until, well, forever. SpaceX, on the other hand, needs to 'turn a profit'. Where the "international" thing may fall in place is if SpaceX gets serius about mars and other countries want "in" on the project, supplying modules for the Mars colony or any other "help" they can provide to SpaceX. That could happen. In fact, given the current trajectory of NASA, probably even likely. Just what do we mean by "the international thing"? But unless a place like Australia could provide a huge cost and logistics benefit to have SpaceX launch/land there, SpaceX might not be so interested when you consider transportation logistics for modules built in USA. You are looking through the wrong end of the telescope. Australia would hire SpaceX as a *vendor* to supply materials and technology for the *Australian* space program. Huge benefit to not having to bootstrap it all by yourself. You hire the best experts in the world. If not SpaceX, then maybe Bezos' Blue Origin would oblige. Yes it's tech transfer, but with a *buyer* whose funds (remember it has to be a *profitable* proposal for SpaceX) could finance who knows what at SpaceX? I don't see SpaceX going that route. They plan on making their money on launch services. Why would they sell technology to allow a competitor to set up? In the case of a LEO assembly/refueling spot to later go to Mars, would launching from 12°S (northern Australia) offer significant performance advantage over 28°N (Canaveral)? Some. But setting Mars aside, for the inhabitants of Oz certainly! If it helps clarify what I'm saying let's say the deal is between Australia's equiv. of NASA and Blue Origin. Just to keep Mars confusion off the table.... Blue Origin is willing to do things like sell engines, etc. I don't see SpaceX doing that. Different business models. -- "The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." --George Bernard Shaw |
#32
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Space X 2nd stage recovery
David Spain wrote on Wed, 25 Apr 2018 13:56:49
-0400: On 4/24/2018 5:54 PM, Fred J. McCall wrote: JF Mezei wrote on Tue, 24 Apr 2018 16:36:20 -0400: On 2018-04-24 14:21, David Spain wrote: I am of the opinion that the existing F9 and F9H architectures will be (crew-wise) underutilized. Unless the space station life is extended beyond 2025, FH and Dragon2 may very well remain the workhorse for mnanned space in USA. So Boeing is irrelevant in your mind? Not to my mind. Which makes for even more infrequent flights to ISS by SpaceX. Also doesn't require crewed F9H for any of these either. Not to mine, either. That means each gets a couple of crew flights per year for the next decade or so. I think Musk's latest remarks are that he doesn't intend to 'man rate' Falcon Heavy because there is no current mission that requires it. And unless there is real funding for manned space programme beyond ISS, nobody will see much business case to invest in manned space programme from now on, unless you go for it on your own (aka: SpaceX with BFR to Mars). The issue here is that Bigelow seems to have jumped in bed with ULA. If that extends to ferrying supplies and 'guests' to 'space hotels', they might not let SpaceX vehicles dock. Yes. That thought had crossed my mind as well. I hope not. I would like to think that third parties might buy Bigelow modules, which would be delivered on orbit with ULA boosters but it would then be up to the owner to supply and crew the thing. Any sane operator would want to keep operating costs as low as possible and that is NOT ULA. Even Vulcan doesn't promise the sort of price point you'd need to hit to compete with SpaceX. Where the "international" thing may fall in place is if SpaceX gets serius about mars and other countries want "in" on the project, supplying modules for the Mars colony or any other "help" they can provide to SpaceX. Or just people who want to go to Mars. If there are enough, it would make sense to launch from almost anywhere. But unless a place like Australia could provide a huge cost and logistics benefit to have SpaceX launch/land there, SpaceX might not be so interested when you consider transportation logistics for modules built in USA. I addressed this elsewhere. A contract that would allow some assembly in Australia, some would be shipped out from US. Eventually Australia might be supplying some of their own parts. Remember, BFR Spaceship can do point to point travel on Earth and land anywhere there's a big enough piece of concrete. True once that happens. But I am purposely leaving BFR (and Mars) out of it. Trying to make a case for why someone might be interested in existing F9(H) or Blue Origin hardware. Getting back to F9 and Dragon V2 specifically. Propulsive landing and landing gear were removed from Dragon V2 at NASA's behest. But if there were another 3rd party customer that wanted that capability, it'd be a way to get a customer to invest in and help pay for the testing needed to make it a reality. I'd like to see that. It wasn't just at NASA's behest. Proving it safe and reliable was just too expensive for SpaceX to want to undertake it when it wasn't needed. [snipped] I think all the inspection and such will occur at the launch site. That makes locating the facility outside the US something of an ITAR issue. I wouldn't expect Australia to be a problem, but you never know... Me either, that's why I used them as an example. -- "The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." --George Bernard Shaw |
#33
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Space X 2nd stage recovery
JF Mezei wrote on Wed, 25 Apr 2018
14:05:29 -0400: On 2018-04-25 07:27, Jeff Findley wrote: This makes no sense to me. ISS is the reason Dragon 2 and Starliner were both built and will be flying within a year two with crew. Not extending ISS beyond 2025 spells uncertainty for both Dragon 2 and Starliner. I was refering to any new developments. Dragon and Starliner's development costs are being paid by NASA and the flights to ISS till 2025. After that, those vehicles remain "available" if needed, but there wouldn't be any justification to build anything new since restarting Dragon or Starliner production would cost much less than designing from new. Yes and no. I've seen significant 'obsolescence programs that had to redesign missiles because you just couldn't get the old parts anymore. Depends if they have a destination. A Bigelow Aerospace inflatable space station could be a possible destination. And who pays for it? Do you have long term supply of space tourists willing to pay $20m each? Who pays for it? Whoever wants to. Whose ass did you pull that $20 million number out of? I think you're a little high (about 2x). And that's using Falcon 9/Dragon. That's BFR/BFS not Dragon 2. WTF are you trying to say here? SpaceX isn't bloody likely to launch from anywhere but the US. Someone had mentioned international launches and specified Australia. Hence my question on whether launching from northern australia would give enough advantage to offset the logistics/costs of transportation. I don't think there are any big differences in logistics/costs of transportation. They're building BFR at the Port of LA. They're going to have a long sea voyage, regardless of where they launch from. With regards to SpaceX being a US company, what law prevents it from launching from another country? It can form SpaceX(Australia) subsidiary to launch from Australia if it wanted to. It could, but then it would be transferring rocket technology to a foreign entity. Look up 'ITAR'. -- "Ignorance is preferable to error, and he is less remote from the truth who believes nothing than he who believes what is wrong." -- Thomas Jefferson |
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Space X 2nd stage recovery
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Space X 2nd stage recovery
JF Mezei wrote on Thu, 26 Apr 2018
16:31:46 -0400: On 2018-04-26 16:21, Fred J. McCall wrote: You're going to have to do that to get it from LA to the launch site anyway. They're building these things in LA because they're too big to move other than by ship. That means they're going down through Suez to get to East Coast launch sites, so they're making a very long ocean voyage anyway. Why not Panama? The Panamanian government built Panama2 to handle the current crop of mega container ships that used to be unseen in the Atlantic. Sorry. I meant Panama. Any chance BFR/BFS might get to Texas by road/rail and then by barge? No. Both too long and too wide. Also too heavy for road transport. Haven't see the diameter numbers, but could a "Beluga" type of aircraft be used to ferry BRS/BFS segments across? No. And what do you mean 'segments'? There are precisely two pieces. One is 48m x 9m (not including wings) x 85 tonnes. The other is 58m x 9m x ???. I don't find a dry mass number for the booster, but I can't imagine it's less than the BFR Spaceship. Could an SCA type of carriage of BFS atop a 747/777/whatever be feasable? (probably multiple flights each carrying a segment). No. Again, there are only TWO 'segments'; the BFR and the BFR Spaceship. Each of those pieces is too long and too big around for rail, road, or air travel. BFR Spaceship is both bigger and heavier than the Shuttle and it was carried on the biggest airplane they could find. -- "Ignorance is preferable to error, and he is less remote from the truth who believes nothing than he who believes what is wrong." -- Thomas Jefferson |
#36
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Space X 2nd stage recovery
"Fred J. McCall" wrote in message
... No. Both too long and too wide. Also too heavy for road transport. Haven't see the diameter numbers, but could a "Beluga" type of aircraft be used to ferry BRS/BFS segments across? No. And what do you mean 'segments'? There are precisely two pieces. One is 48m x 9m (not including wings) x 85 tonnes. The other is 58m x 9m x ???. I don't find a dry mass number for the booster, but I can't imagine it's less than the BFR Spaceship. Could an SCA type of carriage of BFS atop a 747/777/whatever be feasable? (probably multiple flights each carrying a segment). No. Again, there are only TWO 'segments'; the BFR and the BFR Spaceship. Each of those pieces is too long and too big around for rail, road, or air travel. BFR Spaceship is both bigger and heavier than the Shuttle and it was carried on the biggest airplane they could find. Air Travel is unlikely, but possible. The Boeing Dreamlifter almost might work. It has a payload of 113 tonnes and an interior diameter of 8.38m. So not quite big enough, but for a fee, I'm sure Boeing is willing to make a larger diameter core. I can't find a firm number for length, but the Dreamlifter itself is about 72m long and the full length of a 787 itself varies in length, but the 787-8 is 58m. The Dreamlifter though I believe only transports the main fuselage, not the nose and empennage, so the length might be close. That said, given the aerodynamics, I can't see a slight lengthening being a problem. The An-225 has a payload of over 250 tonnes and could almost certainly mount BFR/BFS on top. I suspect for the first few deliveries they'll go with a cargo ship, but via air isn't completely out of the question. I suspect the FAA won't permit flying brand new BFRs over the Continental US until quite a few flights have occurred. -- Greg D. Moore http://greenmountainsoftware.wordpress.com/ CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net IT Disaster Response - https://www.amazon.com/Disaster-Resp...dp/1484221834/ |
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Space X 2nd stage recovery
JF Mezei wrote on Thu, 26 Apr 2018
18:45:41 -0400: On 2018-04-26 17:14, Fred J. McCall wrote: Without a destination in LEO, I wouldn't expect a huge market for LEO trips. Falcon Heavy/Dragon V2 could do a Moon flyby with free return, but the bulk of that trip is going to be boring. You'll spend very little time near the Moon and the system doesn't have the capability to make that longer. That means the 'work horse for manned space flight will by default wind up being SLS/Orion, which massively sucks. Considering SpaceX is much better at delivering stuff on time and on budget, wouldn't it be able to deliver a Dragon service module with the extra oumph! to permit Moon orbit/return before the "real" service module is delivered for Orion? No. They could no doubt develop such a system, but it's not going to be something that's going to be done quickly. I'm sure I've gone over the reasons before, Mayfly. An Orion capsule weighs a bit over 10 tonnes at launch. Unfortunately, I don't find a 'launch weight' for Dragon V2, so I'll extrapolate from dry mass (6.4 tonnes) and say it probably weighs within a tonne or so of Orion when it's loaded with propellant for the Super Dracos and a crew of 7. Now, you need to add a Service Module with a real engine, fuel, etc. Launch mass for the Orion Service Module is around 15.5 tonnes, but 9 tonnes of that is fuel (and it carries about twice as much fuel as it needs for a lunar mission). Given that, call the Dragon V2 service Module coming in around 11-12 tonnes fully fueled (with half the fuel Orion has). That gives you a total Dragon V2 system launch mass of around 20-22 tonnes in order to do 'Orion-like' missions. That mass is probably within the TLI capability of Falcon Heavy in expendable mode. However, you would need to man-rate Falcon Heavy (which SpaceX doesn't plan to do because it's so time consuming and expensive), which would involve repeating all the testing that has been done on the current Dragon V2 (at least). The Orion Service Module should deliver in less than a year. I seriously doubt SpaceX could design one from scratch in that time. Then again, is there any market to make a sightseeing triop to the moon without landing? Apparently. Musk had an offer in hand that didn't even involve staying near the Moon for any length of time. Wouldn't it have greater market potential to orbit the Earth for a week, which gives you much better scenery? (in terms of tourist potential). I'd consider either to be a little out there, what with 7 people jammed into a capsule for that amount of time. How much would Dragon V2 need to be changed to rise above Van Alen belt and get full brunt of radiation? It probably wouldn't, but that's the least of the issues involved. -- "The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." --George Bernard Shaw |
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Space X 2nd stage recovery
Jeff Findley wrote on Thu, 26 Apr 2018
20:15:20 -0400: In article , says... On 2018-04-26 17:14, Fred J. McCall wrote: Without a destination in LEO, I wouldn't expect a huge market for LEO trips. Falcon Heavy/Dragon V2 could do a Moon flyby with free return, but the bulk of that trip is going to be boring. You'll spend very little time near the Moon and the system doesn't have the capability to make that longer. That means the 'work horse for manned space flight will by default wind up being SLS/Orion, which massively sucks. Considering SpaceX is much better at delivering stuff on time and on budget, wouldn't it be able to deliver a Dragon service module with the extra oumph! to permit Moon orbit/return before the "real" service module is delivered for Orion? Big problem. It simply won't work. You see, neither Dragon nor Dragon V2 has a "service module". They have a "trunk" which is little more than a hollow tube to which the solar arrays are attached. Everything that's in Orion's service module is *inside* Dragon and Dragon V2. That's because SpaceX reuses everything they can. Throwing away a couple solar arrays and an empty tube is a lot cheaper than throwing away an entire Orion service module. If they're going for lunar missions they're going to be throwing away an entire Falcon Heavy, so throwing away a Service Module probably isn't a big deal. -- "The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." --George Bernard Shaw |
#39
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Space X 2nd stage recovery
"Greg \(Strider\) Moore" wrote on Thu,
26 Apr 2018 22:20:51 -0400: "Fred J. McCall" wrote in message .. . No. Both too long and too wide. Also too heavy for road transport. Haven't see the diameter numbers, but could a "Beluga" type of aircraft be used to ferry BRS/BFS segments across? No. And what do you mean 'segments'? There are precisely two pieces. One is 48m x 9m (not including wings) x 85 tonnes. The other is 58m x 9m x ???. I don't find a dry mass number for the booster, but I can't imagine it's less than the BFR Spaceship. Could an SCA type of carriage of BFS atop a 747/777/whatever be feasable? (probably multiple flights each carrying a segment). No. Again, there are only TWO 'segments'; the BFR and the BFR Spaceship. Each of those pieces is too long and too big around for rail, road, or air travel. BFR Spaceship is both bigger and heavier than the Shuttle and it was carried on the biggest airplane they could find. Air Travel is unlikely, but possible. The Boeing Dreamlifter almost might work. It has a payload of 113 tonnes and an interior diameter of 8.38m. So not quite big enough, but for a fee, I'm sure Boeing is willing to make a larger diameter core. I can't find a firm number for length, but the Dreamlifter itself is about 72m long and the full length of a 787 itself varies in length, but the 787-8 is 58m. The Dreamlifter though I believe only transports the main fuselage, not the nose and empennage, so the length might be close. That said, given the aerodynamics, I can't see a slight lengthening being a problem. The An-225 has a payload of over 250 tonnes and could almost certainly mount BFR/BFS on top. I suspect for the first few deliveries they'll go with a cargo ship, but via air isn't completely out of the question. I suspect the FAA won't permit flying brand new BFRs over the Continental US until quite a few flights have occurred. Start with the basics. How would they get it to the airport? I don't think they plan on changing from ships, given the location of the factory. -- "The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." --George Bernard Shaw |
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Space X 2nd stage recovery
JF Mezei wrote on Fri, 27 Apr 2018
01:27:46 -0400: On 2018-04-26 20:15, Jeff Findley wrote: Big problem. It simply won't work. You see, neither Dragon nor Dragon V2 has a "service module". They have a "trunk" which is little more than a hollow tube to which the solar arrays are attached. Everything that's in Orion's service module is *inside* Dragon and Dragon V2. Can't you put bigger tanks (instead of cargo) in the trumk for extra fuel and ECLSS consumables? No. If needed, how hard it it to make a longer trunk to accomodate move volume needed for extra tanks? You need a real Service Module if you want to go outside LEO. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
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