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#31
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Were liquid boosters on Shuttle ever realistic?
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#32
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Were liquid boosters on Shuttle ever realistic?
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#33
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Were liquid boosters on Shuttle ever realistic?
JF Mezei wrote:
On 2017-10-27 18:49, Greg (Strider) Moore wrote: Actually delivers? They've done 15 flights this year and expect at least 4 more (I'm not counting Heavy as I expect that will slip). What percentage were re-used stage 1s ? Enough to service all customers asking for them. Consider commercial aircraft. There is a huge difference between building the couple of prototypes to do flight tests and going into production and ramping up production. The prototypes get a lot more "manual" work to get things to fit/work. But to go into production all those production glitches need to be fixed otherwise they can't ramp up production since each plane takes too long to assemble. The 'used' boosters are the same as the new ones, so all the 'prototype' **** was done long ago. There is very little 'automated assembly' in aerospace in general and even less when it comes to rocket boosters. SpaceX is basically at the "prototype" stage for reflying stages. It hasn't delivered yet on high rate and quick turn around of reflying stages. Name a customer who has asked for a 'used' stage and hasn't gotten one. You don't fly payloads worth hundreds of millions of dollars on 'prototypes', you nitwit. Just because everyone has confidence that it will deliver, it doesn't mean that it has delivered. Also not clear what percentage of landings might cause more than a easily replaced broken leg (compressed crush zone). Say, for sake of discussion, only 50% of stages can be reflown, this could change SpaceX plans to wind down Falcon 9 production to start BFR production because they would need higher stock of new Falcon 9s to cope with fact they aren't recyling 100% of stages. Say, for sake of discussion, that each used stage must be bathed in magic pixie dust produced by rainbow unicorn farts. It makes about as much sense as what you're saying. A compressed crush zone is NOT a "broken leg". This has been explained to you repeatedly, but in true Mayfly fashion it doesn't seem to stick in your brain for more than a very short time. Let me try again. The emergency crush core on Falcon 9 landing legs is there for when the landing is so 'hot' that the leg would take damage from the impact. In this case, the crush core, well, crushes and absorbs all that energy. The leg itself is unlikely to take damage unless the entire crush core is expended, which has NEVER happened. The crush core is a cartridge that is designed to be easily inspected, removed, and replaced as needed. Just what else do you think is being 'damaged' in your 50% 'for discussion' catastrophic damage rate? So there needs to be more empirical data on landings, refurbishements before SpaceX would know for sure how thing will pan out. You will never think there is enough 'empirical data' to draw a conclusion because you insist on nitwittery. or it could be that even with the hard landings, the stages are far from having any structural damage and fixing legs is the only repair needed, so it become more of a 1 and 0 (either it lands and can be re-used easily, or goes kaboom on landing). Which is where it's at. Just what 'structural damage' do you think can occur when the energy absorbing crush core hasn't been fully crushed? And while "going kaboom" on landing hasn't happened in a while, is this just stroke of luck, or has SpaceX realy gotten their software to work reliably enough to conclude that "kabooms" won't happen again? How many more landings before such a conclusion can be made? It's rocketry, you nitwit. A 'kaboom' is always possible. Musk said (back at the beginning of 2016) that he expected about a 70% success rate with recovery in 2016 (actual rate was 63% and one more success would have taken it to 75%) when recovery was still billed as 'experimental' and 90% in 2017 (so far it's 100%) when recovery is considered 'production'. Developmental tests of the capability were performed in 2014-2015, including both water landings and some barge attempts. Experimental test was conducted in 2016. 'Production' use started at the beginning of 2017. Success rate through experimental test and production use is 19 attempts for 14 successes (just under 74%) with all the failures occurring during the experimental test phase. That's a pretty damned good record when it comes to rocket testing. Musk seems to think he has enough data to declare it 'production use' starting at the beginning of this year. I believe him before I belief **** you pull out of your ass. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
#34
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Were liquid boosters on Shuttle ever realistic?
JF Mezei wrote:
On 2017-10-27 18:52, Fred J. McCall wrote: You try far too hard to muddy things up. And some cheer lead too much for SpaceX. Just because SpaceX has great image and people have confidence it will deliver on what it promises does not mean that it has already delivered. OK, I was being polite. Now I will be less so. You're a ****ing idiot who is ignorant of the facts and can't retain them when they are given to you. After two years of developmental test (2014-2015) Musk predicted the success rates for both experimental test (2016 - 70% predicted vs 63% achieved; one more success would have been 75%) and operational use (2017 - 90% predicted vs 100% achieved so far) with pretty astonishing accuracy. You don't do that on "not enough data" and if it was 'just lucky guesses' he should be buying lottery tickets to fund SpaceX. That's not cheerleading. That's the bloody facts, which you seem to be immune to. SpaceX declared landing the first stage 'operational' as of this year and has started commercially offering reflown boosters as an option (first commercial launch in March of this year). Again, that's the FACTS, you ignorant assclown. -- "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 |
#35
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Were liquid boosters on Shuttle ever realistic?
On 17-10-29 05:32 , JF Mezei wrote:
On 2017-10-28 21:58, Fred J. McCall wrote: SpaceX declared landing the first stage 'operational' as of this year and has started commercially offering reflown boosters as an option (first commercial launch in March of this year). Again, that's the FACTS, you ignorant assclown. So you are stating that reflying 1 stage proves that they can quickly turn around stages and offer high frequency launch of reflown stages? According to Wikipedia (https://en.wikipedia.org/wiki/Falcon_9#Notable_flights, heading "Relaunch of previously-flown first stages") there have so far been *three* reflights of Falcon 9 boosters, not one. All successful, and all relanded the booster, again. -- Niklas Holsti Tidorum Ltd niklas holsti tidorum fi . @ . |
#36
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Were liquid boosters on Shuttle ever realistic?
"JF Mezei" wrote in message
eb.com... On 2017-10-28 21:47, Fred J. McCall wrote: Musk seems to think he has enough data to declare it 'production use' starting at the beginning of this year. I believe him before I belief **** you pull out of your ass. Am not debating that they can do it. And yes, they are selling launches on refurb stages. But as I recall, they've only have 1 launch so far on a refurb stage. All those sales are for future launches. When those happen, then SpaceX will have demonstrated it can deliver on turning around landed stages quickly enough to meet customer demand. You really need to learn to use Google. There are 3 reflights so far, and 2 more scheduled. So that's about 2% of the flights. Iridium has bought 2 more flights (for next year) on used boosters (ironically these won't be recovered). And if Heavy takes off this year, that's 2 more boosters that will be reflown this year. If not, next year. Until then, it is cheer leading to state that they have proven it. And the day may come where a launch on refurb stage will be sold at a premium since it pretty much eliminates the 0-day defects on a totally new stage. Just because the future is extremely promising doesn't mean SpaceX has already demonstrated it. -- 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/ |
#37
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Were liquid boosters on Shuttle ever realistic?
"JF Mezei" wrote in message
web.com... On 2017-10-29 02:37, Niklas Holsti wrote: According to Wikipedia (https://en.wikipedia.org/wiki/Falcon_9#Notable_flights, heading "Relaunch of previously-flown first stages") there have so far been *three* reflights of Falcon 9 boosters, not one. All successful, and all relanded the booster, again. Thank for clarification. Stll not the 15 or so flight another poster claimed. No one claimed 15 REflights. We've been pointing out 15 flights, with 4 more definitely planned. That's a higher rate than pretty much anyone booster. This for a system that's still relatively new. Oh and Boeing moved an X-37B flight to Falcon 9 off of one of their own ULA boosters. And they've shown an ability to reschedule payloads as things change. If nothing else, the ability to stack and destack in under 2 weeks (I think it's actually just a few days) is a huge improvement over existing launchers. They note that the the first reflight resulted in the booster, despite landing fine, was retired. I would assume SpaceX wants to figure out how many times boosters can be re-used, and retiring after only 2 launches isn't that great. Sure it is. First it's historical. Secondly you move in incremental steps. But this is another example of being too early to draw conclusions on just how reusable they will be. No, you keep making assumptions about what most of us think. -- 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/ |
#38
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Were liquid boosters on Shuttle ever realistic?
"JF Mezei" wrote in message
web.com... On 2017-10-28 15:38, Jeff Findley wrote: So what? They're doing better at turning around recovered first stages to be re-flown faster than any of the competition The only "re-use" competition is the Shuttle and it wasn't a commercial endeavour. Landing a just launched stage doesn't save any money. It costs money. Launching a payload with a re-used stage 1 is what saves you money. The Block 5 has improvements to the design to help with reuse. One could infer that those improvements are a sign that the current Falcon 9 is harder to re-use as the cheer leaders say it is. No, this is how engineering is done. Incremental steps as you learn more. SpaceX will only get better at this while the competition (aside from Blue Origin, who's still working on the BE-4 engine for New Glenn) are not even trying to reuse anything. The argument isn't whether SpaceX is ahead or other or not. The mere fact that they have demonstrated they can land a stage, and have re-used at least 1 stage means they are way ahead of anyone else. But that doesn't mean that they have proven that they can already quickly turn around every landed Falcon 9. They've demonstrated the concept, they've demonstrated they can land stages, they have demonstrated they can refly at least 1 stage. But havent yet demonstrated they can have short turn around between landing pad and launch pad such that it allows high launch rate OF RE-USED STAGES. Just because it is very likely that they will be able to turn these around quickly doesn't translate to them having demonstrated it. Just because there are improvements coming that will make future refurb even easier doesn't mean that they have demonstrated it already. The crush core is more likely to be used up on high energy launches. On a commecial aircraft, after a hard landing, the aircraft is put "off line" for inspections. So I would assume that if a crush core gets used up fully, the stage may require more time to be certified for reflight. I am not questioning the huge game changing advantage SpaceX has in having developped re-usable stages. Am not questioning that they have proven they can land stages and re-use at least 1. What they haven't proven yet is the ability to ramp up refurbishement to do quick turn around from landing pad to launch pad. It's too early for them to have demonstrated it. Give them time. But I was curious. Booster 1035 will have reflown in less than 6 months. Looking at the list, right now it looks like 6 months on average. That's similar to the first few flights of the shuttle. But, Musk's goal is to do a reflight within 24 hours. I suspect he'll do it within the next year or two, if only as a demonstration. I suspect we'll see 1-2 weeks between reflights down the road. -- 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/ |
#39
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Were liquid boosters on Shuttle ever realistic?
JF Mezei wrote:
On 2017-10-28 15:38, Jeff Findley wrote: So what? They're doing better at turning around recovered first stages to be re-flown faster than any of the competition The only "re-use" competition is the Shuttle and it wasn't a commercial endeavour. Landing a just launched stage doesn't save any money. It costs money. Launching a payload with a re-used stage 1 is what saves you money. But SpaceX is going to the trouble to land them, so presumably they think they're going to save money. The Block 5 has improvements to the design to help with reuse. One could infer that those improvements are a sign that the current Falcon 9 is harder to re-use as the cheer leaders say it is. One could infer that if one was an idiot. Sane people with actual working brains would infer that the current Falcon 9 is harder to re-use than they would like it to be, which is something entirely different than what you said. SpaceX will only get better at this while the competition (aside from Blue Origin, who's still working on the BE-4 engine for New Glenn) are not even trying to reuse anything. The argument isn't whether SpaceX is ahead or other or not. The mere fact that they have demonstrated they can land a stage, and have re-used at least 1 stage means they are way ahead of anyone else. I'm surprised you remember this, Mayfly. But that doesn't mean that they have proven that they can already quickly turn around every landed Falcon 9. But that would certainly be the way to bet. This will never be 'proven' to your satisfaction, because there will always be more stages to turn around. They've demonstrated the concept, they've demonstrated they can land stages, they have demonstrated they can refly at least 1 stage. But havent yet demonstrated they can have short turn around between landing pad and launch pad such that it allows high launch rate OF RE-USED STAGES. Nor do they need to. You seem quite confused about how this 'needs' to work to be viable. Turn around doesn't need to be particularly "short term". It just needs to be cheaper than manufacturing a new one, which is pretty much a given. If my total launch rate is 17 launches per year and I have 34 'used' stages in stock, I can take as long as a year to 'turn' them and still meet launch schedules. Not that it will take that long. You could completely disassemble, inspect, and reassemble the stage in much less time than that. Just because it is very likely that they will be able to turn these around quickly doesn't translate to them having demonstrated it. Just because there are improvements coming that will make future refurb even easier doesn't mean that they have demonstrated it already. They will never 'demonstrate' it to your satisfaction, nor do they need to. The crush core is more likely to be used up on high energy launches. On a commecial aircraft, after a hard landing, the aircraft is put "off line" for inspections. So I would assume that if a crush core gets used up fully, the stage may require more time to be certified for reflight. I would certainly expect so, BUT THAT HAS NEVER HAPPENED IN THE ENTIRE HISTORY OF FALCON 9. I am not questioning the huge game changing advantage SpaceX has in having developped re-usable stages. Am not questioning that they have proven they can land stages and re-use at least 1. What they haven't proven yet is the ability to ramp up refurbishement to do quick turn around from landing pad to launch pad. It's too early for them to have demonstrated it. They don't need to do it. That's not the point of the exercise. Nobody is talking about refueling a stage after it lands and reusing it immediately for any Falcon rocket. Unless you think the cost of landing, reconditioning, and reusing a stage is more than the cost of a new stage (and if you do you're a Falcon idiot), SpaceX has proven everything it needs to prove. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
#40
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Were liquid boosters on Shuttle ever realistic?
JF Mezei wrote:
On 2017-10-28 21:47, Fred J. McCall wrote: Musk seems to think he has enough data to declare it 'production use' starting at the beginning of this year. I believe him before I belief **** you pull out of your ass. Am not debating that they can do it. And yes, they are selling launches on refurb stages. But as I recall, they've only have 1 launch so far on a refurb stage. All those sales are for future launches. When those happen, then SpaceX will have demonstrated it can deliver on turning around landed stages quickly enough to meet customer demand. They just started selling flights on 'refurb stages' this year. Even at the high launch rate that SpaceX has, just how many opportunities do you think there are to refly stages? And what, in your mind, drives how fast they must turn them? They have almost a year's worth of 'used' stages in stock. You'd like to have a few more than that on hand in case something goes wrong with a launch or booster recovery, but that allows the better part of a year to refurb a stage and still be 'fast enough' and that's pretty much a no brainer. I say 'pretty much', because you don't seem to get it. Until then, it is cheer leading to state that they have proven it. Bull****. And the day may come where a launch on refurb stage will be sold at a premium since it pretty much eliminates the 0-day defects on a totally new stage. Unlikely, since that sort of kills the whole thing. The idea is LOWER COST TO ORBIT, not higher. Just because the future is extremely promising doesn't mean SpaceX has already demonstrated it. Except, of course, they pretty much have. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
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