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More Flights of SLS Block 1
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#12
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More Flights of SLS Block 1
Jeff Findley wrote on Tue, 17 Apr 2018
05:51:50 -0400: In article , says... JF Mezei wrote on Sun, 15 Apr 2018 20:35:30 -0400: On 2018-04-14 20:52, Jeff Findley wrote: I'm talking about today. SLS is bull$hit today. You don't allow something this expensive and useless to keep on going due to decisions made in the past based on assumptions that have changed. But it can be argued that until SpaceX's manned Dragon flies succesfully, it could be wise to continue NASA's manned rockets development just in case. (what happens if Musk's business has to go chapter 11, or some technical probvlem indefinitely delayed manned Dragon etc etc. You're confusing rockets with capsules. Manned Dragon and Orion don't compete, since the purpose of one is LEO trips and that's only a secondary mission for the other. Dragon 2 has been designed to handle reentries from lunar missions. Pretty much the same sort of reentry that Orion is designed to handle. For now, SpaceX has canceled the commercial flight of people around the moon (launched by Falcon Heavy), but I doubt it was due to any deficiency in Dragon 2. I don't see any fundamental reason Dragon 2 couldn't fulfill the crew rotation role for Deep Space Gateway. I don't know about Boeing's Starliner. There are 'fundamental reasons' and then there are 'fundamental reasons'. Dragon needs a much larger and more capable Service Module if it's going to do that. Keep in mind that one of the big delays in Orion is the late delivery of the European Service Module. And if Dragon is to become real say by end of 2018, then continuing SLS until end of 2018 isn't that big a deal in the grand schjeme of things (where military spends 700 billion a year). You're comparing apples (manned capsules) with aardvarks (launch vehicles). Currently the only manned missions planned for SLS/Orion are for Deep Space Gateway. There's a Mars orbital mission at the end of that pipeline. Falcon Heavy/Dragon 2 could likely perform the same missions. Except it can't, for the same reason that SLS Block 1 can't. Falcon Heavy is even shorter of cargo capacity than SLS Block 1 is. Orion may be designed to be a one size fits all deep space capsule, but its role on Deep Space Gateway is that of a crew taxi, just like ISS. Deep Space Gateway will even have its own airlock module, relieving Orion of the need to serve as one. Actually my reading is that it's a bit more than that. It feels to me like the Orion docking capability is how the pieces of the Gateway get put together. And that brings us back to Dragon needing a more capable Service Module and Falcon Heavy not having enough boost to do the job. Commercial launch vehicles are here and they're cheaper than ever. Not manned ones. (not yet) You're comparing apples (manned capsules) with aardvarks (launch vehicles). Then perhaps we should be comparing manned space transportation systems to manned space transportation systems. Orion has no planned role beyond manned taxi. The combination of Falcon Heavy/Dragon 2 looks like it can do everything that SLS/Orion is required to do for Deep Space Gateway. Again, I think not. See above. Dragon doesn't have the life support time to last for the early missions. Dragon/Falcon Heavy do not quite have the capability to actually carry the pieces of the Gateway and get them mated. This is the classic spin-off argument. That's almost always bull$hit too because the SLS program isn't doing much in the way of scientific research, No debate there. I was arguing that NASA direction should have been to do massive R&D to develop new technooogies instead of being directed to build a new rocket with technology choices imposed by politicians. And just who picks the 'new technologies'? NASA, as always. The aeronautical side is going to be flying a manned low sonic boom demonstrator in upcoming years. It's the sort of thing NASA has been doing for decades. But they haven't been doing it in rocketry, where they have this incestuous relationship with ULA. My suspicion is that NASA switching to 'technology development' would just wind up being a subsidy to ULA so that they wouldn't have to do it and 'outsiders' like SpaceX and Blue Origin would get nothing useful to them. But they'll still be dropping *all* of the SLS hardware in the ocean for each and every flight. In a world where reusables are coming into their own, that's just stupid. At the time ARES/Orion were launched, it was decided expandable was cheaper than re-usable. SpaceX proved that to be very wrong, but that is only very recent. Well, no, not so much. Agreed. DC-X/XA was a very successful demonstrator. The fact that NASA screwed the pooch on X-33 had everything to do with NASA picking the worst of the three X-33 proposals and then mis-managing the program until it finally died. Either of the other two proposals had a higher chance of success. I'd have gone with the VTVL proposal since VTVL had just been proven to be quite viable. JF should note that DC-X/XA happened long before SpaceX was even an idea, let alone a company. Yeah. I was really disappointed when DCX didn't have a 'follow-on' DCY. For NASA, it is still better to have a bloody expensive SLS/Orion than nothing (in case all other projects fail). Except that NASA is more likely to fail (and cause others to fail by expending preposterous amounts of money) than anyone else. Agreed. SLS especially is an economic, technological, and programatic disaster. Orion isn't all that much better. It's had a lot longer to mature and STILL is not ready. I suspect that once commercial has manned programmes proven and running, it will be the end of NASA trying to build rockets, and NASA's involvement with rockets will be the same as it has for commercial airplanes. Pure R&D. I suspect you're wrong. I think it will take both BFR and New Armstrong flying to finally kill the pork laden monstrosity that is SLS. At least I hope so. We're not going to need three heavy lifters and only one of those will be completely expendable. I wish I had your faith. I think there is so much money sunk in SLS and it's so far along that it will continue until NASA decides to develop yet another launch vehicle. -- "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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More Flights of SLS Block 1
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#14
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More Flights of SLS Block 1
JF Mezei wrote on Tue, 17 Apr 2018
18:51:47 -0400: On 2018-04-17 05:51, Jeff Findley wrote: Boeing's CST-100 (Starliner) is following the same schedule as Dragon 2. The US will have 3 manned capsules, if Orion ever flies. Until they are launching in production with crews, it isn't "'Mission Accomplished" which allows for SLS to be put out of its misery. Again, you are comparing apples and aardvarks. CST-100 and Dragon V2 are LEO taxis. Orion is different and only has LEO as a secondary mission. Unmanned tests this year for both Dragon 2 and Starliner with possible manned tests by the end of the year. Close but no cigar. But once they do fly, I would hope SLS unravels quickly. The boosters that lift both Dragon 2 and Starliner have been successfully flying for a while now, which puts them well ahead of SLS. SLS hasn't gone anywhere. So what? We're talking about where we go from here, not where we should go 10+ years ago! Knowing the context that created the Ares/SLS and Orion projects helps understand why they continue today and why it can be argued that that project being a back remains "valid" until the commercial offerings are real and launching. Let me try it again. Orion is ***NOT*** a 'back up' in case of Dragon V2 or CST-100 failure. Dragon V2 and CST-100 are each other's 'backup plan'. Orion is something different. The boosters that Dragon V2 and CST-100 fly on are both production systems, which SLS is not. I know that SpaceX and Boeing are close. But if the strategy was to have a backup plan until commercial has proven it will work, then one needs to wait till this happens before killimng the SLS boondogle. Let me try it again. Orion is ***NOT*** a 'back up' in case of Dragon V2 or CST-100 failure. Dragon V2 and CST-100 are each other's 'backup plan'. Orion is something different. The boosters that Dragon V2 and CST-100 fly on are both production systems, which SLS is not. But all other projects have not failed. Falcon Heavy is a reality. Both Dragon 2 and Starliner are both set to fly years before Orion. And slowing down Orion/SLS may be a sign that NASA knows this and just keeps the project on extended life support until it is ready to be killed (as opposed to Apollo project when finishing on time was prioroty 1 to get man to the moon and back before 1970. They're not 'slowing it down'. It is failing to meet schedule. Have you read the news? The Exploration Upper Stage for SLS is slipping, BADLY! Yep. But if proof that commercial is working is coming in the next 12 months, then no point in pushing for SLS hard, but still can't argue that commercial replacements exist and make SLS moot. (and until BFR flies, one could argue that Commercial crew won't have same capabilities as SLS so that could be an excuse to continue SLS till first BFR flight (see previous discussion). So your claim is that they're slipping ON PURPOSE? That's preposterous! You need to think politicios of killigh SLS and give politicians the face saving way out of the project without the least political costs (job losses). How's THAT supposed to work? Are you proposing continuing to spend SLS money so jobs aren't lost but not bothering to develop anything with it? If that were true, we'd have just a scant two more years of SLS funding meaning it wouldn't even get to first flight (which is still about 3 years away). I have a feeling the pork will keep flowing at least through a few flights. They have what, 12 engines to burn? 3 flights. (are the 6 "new" SSMEs built already?) My prediction is that they'll shoot those off as Block 1 missions and then claim they need funding for more engines because the new upper stage is now ready. And they'll get it because we'll have spent all that money to develop the new upper stage which will just be thrown away if we don't buy more engines. -- "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 |
#15
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More Flights of SLS Block 1
Jeff Findley wrote on Tue, 17 Apr 2018
19:59:06 -0400: In article , says... Jeff Findley wrote on Tue, 17 Apr 2018 05:51:50 -0400: In article , says... JF Mezei wrote on Sun, 15 Apr 2018 20:35:30 -0400: On 2018-04-14 20:52, Jeff Findley wrote: I'm talking about today. SLS is bull$hit today. You don't allow something this expensive and useless to keep on going due to decisions made in the past based on assumptions that have changed. But it can be argued that until SpaceX's manned Dragon flies succesfully, it could be wise to continue NASA's manned rockets development just in case. (what happens if Musk's business has to go chapter 11, or some technical probvlem indefinitely delayed manned Dragon etc etc. You're confusing rockets with capsules. Manned Dragon and Orion don't compete, since the purpose of one is LEO trips and that's only a secondary mission for the other. Dragon 2 has been designed to handle reentries from lunar missions. Pretty much the same sort of reentry that Orion is designed to handle. For now, SpaceX has canceled the commercial flight of people around the moon (launched by Falcon Heavy), but I doubt it was due to any deficiency in Dragon 2. I don't see any fundamental reason Dragon 2 couldn't fulfill the crew rotation role for Deep Space Gateway. I don't know about Boeing's Starliner. There are 'fundamental reasons' and then there are 'fundamental reasons'. Dragon needs a much larger and more capable Service Module if it's going to do that. Keep in mind that one of the big delays in Orion is the late delivery of the European Service Module. Yes, working with NASA is a p.i.t.a. That service module is based off the ESA ATV, which is flight proven. But NASA required a lot of changes to make it "better". Unfortunately, "better" is the enemy of "good enough". So you want to blame NASA because ESA couldn't hit their schedule? That's a bit of a stretch. Considering the schedule for SLS/Orion, I'd think SpaceX could make whatever modifications are necessary to make it work and it would still be far cheaper than SLS/Orion. Perhaps, but SpaceX would have to develop an actual Service Module instead of a trunk. They need to at least triple the life support capacity of the Dragon V2 and get a read engine and fuel on that Service Module so they can actually do a TLI burn, pick up the piece of the Gateway, and rendezvous and dock with the Gateway so they can get it assembled. All that adds enough weight that it's probably at (if not over) the edge of what Falcon Heavy can do. And if Dragon is to become real say by end of 2018, then continuing SLS until end of 2018 isn't that big a deal in the grand schjeme of things (where military spends 700 billion a year). You're comparing apples (manned capsules) with aardvarks (launch vehicles). Currently the only manned missions planned for SLS/Orion are for Deep Space Gateway. There's a Mars orbital mission at the end of that pipeline. I've not seen that. It must be many, many years out. Original schedule put it out in 2033 or so, but that was all predicated on the completion of the Lunar Gateway. Since the Upper Stage has slid, it's now probably out near 2040. Falcon Heavy/Dragon 2 could likely perform the same missions. Except it can't, for the same reason that SLS Block 1 can't. Falcon Heavy is even shorter of cargo capacity than SLS Block 1 is. I call b.s. The Deep Space Gateway missions all "co-manifest" a module for DSG with an Orion. Split that into two, or more, Falcon Heavy launches. There's a reason they do that. Handwavium doesn't make that reason go away. You'd have to do the rendezvous of the pieces at the Moon because you don't have the grunt to do it in LEO and then go to the Moon like what was done for Apollo. That means every load essentially needs a 'service module' to get it into Lunar orbit and to rendezvous. Yes, you can break the thing into 12,000,000 discrete parts and launch them all separately, but it's hardly practical. EOR was a thing long before LOR took over because it was seen as the way to get to the moon faster in order to beat the "godless commies" to the moon. There is zero reason we can't do EOR today with Falcon Heavy. See above. Orion may be designed to be a one size fits all deep space capsule, but its role on Deep Space Gateway is that of a crew taxi, just like ISS. Deep Space Gateway will even have its own airlock module, relieving Orion of the need to serve as one. Actually my reading is that it's a bit more than that. It feels to me like the Orion docking capability is how the pieces of the Gateway get put together. And that brings us back to Dragon needing a more capable Service Module and Falcon Heavy not having enough boost to do the job. So give it a more capable service module. Or, heaven forbid, launch Orion on Falcon Heavy and a DSG module on another Falcon Heavy. I don't think Falcon Heavy has enough grunt to get an Orion to TLI. It's dubious if it has enough grunt to get a Dragon V2 with a sufficiently capable Service Module to TLI. Commercial launch vehicles are here and they're cheaper than ever. Not manned ones. (not yet) You're comparing apples (manned capsules) with aardvarks (launch vehicles). Then perhaps we should be comparing manned space transportation systems to manned space transportation systems. Orion has no planned role beyond manned taxi. The combination of Falcon Heavy/Dragon 2 looks like it can do everything that SLS/Orion is required to do for Deep Space Gateway. Again, I think not. See above. Dragon doesn't have the life support time to last for the early missions. Dragon/Falcon Heavy do not quite have the capability to actually carry the pieces of the Gateway and get them mated. My biggest beef is with SLS. So launch Orion on Falcon Heavy. It's already flown (a boilerplate) on Delta IV Heavy so the b.s. that only SLS can launch it is quite strong smelling. You can launch it but you can't get it to the Moon. Start out looking at the masses. Orion plus Service Module is a little over 26 tonnes at launch. That's a bit more than Falcon Heavy can send to TLI. There are a couple of choices there. Orion carries more fuel than it needs, so perhaps you could get within the TLI capability of Falcon Heavy by dropping a few tonnes of fuel. More likely, though, they're going to want to keep that as safety margin, which brings us to the other possibility. Falcon Super Heavy. Falcon Heavy can get Dragon V2 to TLI, but without an engine and service module you don't have a way to actually burn into lunar orbit or any stay time. The Super Dracos on Dragon V2 have more than enough thrust, but not nearly enough fuel. You could probably get by with a lighter Service Module on Dragon V2 and do something like use the Service Module engine for insertion and rendezvous and the Super Dracos for the return burn to Earth. That probably gets a Dragon V2 just inside Falcon Super Heavy capability. But if you launch Gateway pieces on separate launches, you're going to need to do a lot more maneuvering in lunar orbit, so that makes the Service Module heavier. Then there's life support. Orion has 122+ man days of life support. Dragon V2 has less than 50 man days of life support. The assembly missions for the Lunar Gateway pretty much max out the Orion life support capability, so Dragon V2 needs to nearly triple its current capability. This is the classic spin-off argument. That's almost always bull$hit too because the SLS program isn't doing much in the way of scientific research, No debate there. I was arguing that NASA direction should have been to do massive R&D to develop new technooogies instead of being directed to build a new rocket with technology choices imposed by politicians. And just who picks the 'new technologies'? NASA, as always. The aeronautical side is going to be flying a manned low sonic boom demonstrator in upcoming years. It's the sort of thing NASA has been doing for decades. But they haven't been doing it in rocketry, where they have this incestuous relationship with ULA. My suspicion is that NASA switching to 'technology development' would just wind up being a subsidy to ULA so that they wouldn't have to do it and 'outsiders' like SpaceX and Blue Origin would get nothing useful to them. ULA isn't going to last much longer unless Vulcan/ACES comes very quickly, is super cheap, and can do more than BFR and New Armstrong. I personally think ULA is a "dead man walking". I doubt that NASA funding technology demonstrators would keep them alive, unless those led to something really groundbreaking. Possibly ACES derived fuel depots, but ULA's Vulcan would be too expensive to fuel the thing in an affordable way. Another possibility is an ACES derived lunar lander. I think NASA and USAF will keep ULA running just fine. I think that's a shame, but there you are. But commercially? ULA's got nothing in the pipeline to keep it financially viable in the commercial launch industry. And yet they still get launches. But they'll still be dropping *all* of the SLS hardware in the ocean for each and every flight. In a world where reusables are coming into their own, that's just stupid. At the time ARES/Orion were launched, it was decided expandable was cheaper than re-usable. SpaceX proved that to be very wrong, but that is only very recent. Well, no, not so much. Agreed. DC-X/XA was a very successful demonstrator. The fact that NASA screwed the pooch on X-33 had everything to do with NASA picking the worst of the three X-33 proposals and then mis-managing the program until it finally died. Either of the other two proposals had a higher chance of success. I'd have gone with the VTVL proposal since VTVL had just been proven to be quite viable. JF should note that DC-X/XA happened long before SpaceX was even an idea, let alone a company. Yeah. I was really disappointed when DCX didn't have a 'follow-on' DCY. Agreed. NASA ate that seed corn. DCX showed so much promise. That's one I DO think NASA let die because of Shuttle and ULA expendables. For NASA, it is still better to have a bloody expensive SLS/Orion than nothing (in case all other projects fail). Except that NASA is more likely to fail (and cause others to fail by expending preposterous amounts of money) than anyone else. Agreed. SLS especially is an economic, technological, and programatic disaster. Orion isn't all that much better. It's had a lot longer to mature and STILL is not ready. Agreed. Which is why I'd rather see NASA do commercial contracts for HLV, "deep space" capsules, lunar landers, and etc. Every single one with two or more providers. They'll try to make the argument that that is too high risk and doing two of everything is just too expensive. I think that's a hard case for them to make, given history, so I generally agree with you. I'd rather see them provide a list of requirements and then see what people offer to build and what each costs. Perhaps do an internal estimate of it done 'in house', as well. If nobody comes in low enough, you don't do it. It makes NASA compete with commercial vendors. You'd need an independent review team to review the proposals and you'd need some way to enforce cost estimates. I suspect that once commercial has manned programmes proven and running, it will be the end of NASA trying to build rockets, and NASA's involvement with rockets will be the same as it has for commercial airplanes. Pure R&D. I suspect you're wrong. I think it will take both BFR and New Armstrong flying to finally kill the pork laden monstrosity that is SLS. At least I hope so. We're not going to need three heavy lifters and only one of those will be completely expendable. I wish I had your faith. I think there is so much money sunk in SLS and it's so far along that it will continue until NASA decides to develop yet another launch vehicle. Sunk cost fallacy is strong with the Congresscritters. But eventually reality will set in. 10x the cost with 1/10th the flight rate will hopefully become obvious after a few years of BFR and New Armstrong flying. Reusable launch vehicles are the wave of the future. It might take 10 years or so, but with stubborn people like Musk and Bezos leading the way, we'll eventually get there. I wish I was that optimistic. -- "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 |
#16
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More Flights of SLS Block 1
JF Mezei wrote on Wed, 18 Apr 2018
04:12:39 -0400: On 2018-04-18 00:11, Fred J. McCall wrote: So you want to blame NASA because ESA couldn't hit their schedule? That's a bit of a stretch. Since SLS is late with high likelyhood of being canbcelled, why should Europe provide for "rapid completion" budgets for something that may never be needed? Because they are UNDER CONTRACT TO DELIVER THE ****ING THING!!!! You don't just get to say "well, I don't think you'll need it so I'm not going to bother to live up to my agreement" in the real world, bucko. And it will be needed, since NASA plans to fly on SLS Block 1 with the Interim Upper Stage. I don't think Falcon Heavy has enough grunt to get an Orion to TLI. It's dubious if it has enough grunt to get a Dragon V2 with a sufficiently capable Service Module to TLI. In the time frames where SLS might be functional, we're talking about BFR, not Falcon Heavy. Let me get this straight. You think BFR/Spaceship will be ready before SLS but that SLS/Orion makes a fine 'back up' for Dragon V2/Falcon 9 and CST-100/Atlas V. Seek treatment for this mental break. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
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