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#21
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Towards routine, reusable space launch.
In article , droleary@
2017usenet1.subsume.com says... For your reference, records indicate that Thomas Koenig wrote: An older version of a Falcon 9 reportedly had 488 tons of total fuel, 147 of it RP-1 (a modified kerosene). Liquid oxygen is quite cheap, and if we give RP-1 a cost of 1 dollar per kg, we probably are in the right ballpark. So, around 150 000 Dollar per launch. This is _very_ low compared to all the other costs. A launch cost around 50 to 60 million dollars now, if I remember the figures right. That?s just the problem: you?re only accounting for the cost of the fuel, whereas I would consider large parts of ?all the other costs? as inherently part of the efficiency equation. After all, if we found a way to eliminate the boosters entirely, the savings is obviously not just from the decrease in fuel. Sure, sure, Star Trek style transporters with infinite range. I'll get right on that. Meanwhile, in the real world, that's not how to optimize the cost of a transportation system in order to minimize the $ per kg to orbit. Jeff -- All opinions posted by me on Usenet News are mine, and mine alone. These posts do not reflect the opinions of my family, friends, employer, or any organization that I am a member of. |
#22
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Towards routine, reusable space launch.
In article , droleary@
2017usenet1.subsume.com says... For your reference, records indicate that Jeff Findley wrote: Balloon launch isn't worth the trades which have to be made, IMHO. Certainly not today, no, or people would be doing it. But as I keep saying, new technologies keep popping up all the time that might make it viable in the future, at least for a few use cases. I have an engineering degree. When developing new things, engineers work with what they have today because they've got schedules and deadlines to meet. You're talking about technologies not yet invented. That's research, not development. The two are not the same. By your definition, a passenger carrying aircraft is "waste" because it flies from one destination to another while carrying passengers. Yes; that is true by any definition. Just because it?s (arguably) the least wasteful mode of transportation we currently have says nothing about how we might travel in the future. Again, to an engineer the future is what you can do with existing tech. SpaceX has reduced launch costs beyond what any of the competition can deliver. They arguably didn't use any new technology at all. DC-X proved VTVL as a viable take of and landing mode. SpaceX applied that to Falcon 9's first stage. They don't give a rat's ass about the "waste" of the actual aircraft having to fly there and back. That same logic could have been used regarding ship or train travel prior to the airplane?s dominance. The point being that they *will* care as soon as a new technology comes along that allows more efficient travel. What that might be in reality is unknown, but clearly something like teleportation or Futurama-style tubes are sci-fi ways of moving just the bits that need to be moved from one location to another. Actually moving freight by rail is the cheapest way to move a ton of goods from point a to point b, assuming you can connect the two by rail. Aircraft have the advantage of speed, so your Amazon order gets there overnight instead of in a week or two, but you're paying for Amazon Prime, which isn't exactly cheap now is it? Two different sets of requirements lead to two completely different vehicles. That's how engineering optimization works. When your hardware costs more than two orders of magnitude more than your propellant does, it makes a hell of a lot of sense to "expend" a bit of propellant to get your expensive hardware back intact. Yes. And I?m just wondering why you can?t just take the next step and admit that eliminating that expensive hardware *completely* would represent a cost saving of two orders of magnitude! You wrote it, but it?s like you weren?t really thinking about what your words actually meant. As an engineer I quite simply can't do that. There is no *proven* existing tech that is cheaper than liquid fueled rocket engines for reaching orbit. What you are trying to get me to admit is that eventually, some day, there may be something better. Sure, there might. Also, monkeys might fly out of my butt. I'm not waiting for sci-fi to become reality. I'm working with what I've got today. Again, that's what engineers do. Jeff -- All opinions posted by me on Usenet News are mine, and mine alone. These posts do not reflect the opinions of my family, friends, employer, or any organization that I am a member of. |
#23
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Towards routine, reusable space launch.
For your reference, records indicate that
Jeff Findley wrote: Sure, sure, Star Trek style transporters with infinite range. I'll get right on that. No, you won’t. But you apparently *will* use it as a straw man to avoid actually addressing the likelihood that new technologies developed in the future will change the economies of space launches. Hell, that’s essentially what SpaceX is demonstrating today. -- "Also . . . I can kill you with my brain." River Tam, Trash, Firefly |
#24
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Towards routine, reusable space launch.
For your reference, records indicate that
Fred J. McCall wrote: Doc O'Leary wrote on Mon, 11 Jun 2018 22:35:20 -0000 (UTC): Chicken and egg. The fact is that we *do* sometimes have to elaborately engineer spacecraft in order to make them small enough to fit into a nose cone or payload bay of a rocket. Head and ass. Cite for such payloads? Be specific. You're posting into a 'sci' newsgroup. Handwavium is not sufficient. Then I must say I note a lack of citations for your own claims. Mine are easy enough to demonstrate. I can literally link to just about *any* payload that unfolds to deploy as evidence. Let’s start with the obvious: https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#/media/File:JWST_launch_configuration.png A different launch vehicle/process might allow us more flexibility when it comes to approaching those very real problems. What 'very real problems' would those be? Asked and answered. Your willful ignorance is not compelling. We're constrained by the real world. Magic materials are right out. Straw man. All Im saying is that its foolish to completely discount new technologies simply because theyre not the rockets you know so well from the past. Go look up what 'straw man' means. It manifestly does NOT mean pointing out reality. Then you need to look up the definition yourself, because I did not suggest anything magical. I simply made note of the fact that new technologies come along all the time. In light of that, it is foolish to be so dismissive of anything but rockets as launch vehicles for all stages of space travel. Cite some of these 'new technologies' and what it takes for them to work. Be specific. You're crossposting into a 'sci' newsgroup. Handwavium is not sufficient. It actually is. My argument is not *for* any one technology. It is simply that rockets have obvious limits, have inherent inefficiencies, and it’s worthwhile to keep our options open when it comes to thinking about different ways to get things into orbit and beyond. What do you propose to replace rockets with, other than 'magic'? You continue to build this same straw man. Don’t be a dick. Please save your thread****ting for Facebook or Twitter. -- "Also . . . I can kill you with my brain." River Tam, Trash, Firefly |
#25
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Towards routine, reusable space launch.
For your reference, records indicate that
Jeff Findley wrote: I have an engineering degree. When developing new things, engineers work with what they have today because they've got schedules and deadlines to meet. You're talking about technologies not yet invented. That's research, not development. The two are not the same. I never claimed they were. The topic of the thread is *not* “what can I build today”, it’s “Towards routine, reusable space launch.” That has nothing to do with today’s technology, and nobody has made the case that continued use of rockets (even reusable ones) can make it happen. Two different sets of requirements lead to two completely different vehicles. That's how engineering optimization works. Indeed. Which is why I argue that rockets alone are unlikely to be the only path to space. And they *definitely* are not the path to deep space. What you are trying to get me to admit is that eventually, some day, there may be something better. Sure, there might. Also, monkeys might fly out of my butt. Really? You think new technologies are butt-monkeys unlikely? Then let’s get you retired, man, because you are *not* allowing your field to innovate nearly as much as it needs to. I'm not waiting for sci-fi to become reality. I'm working with what I've got today. Again, that's what engineers do. Then you should be looking in engineering newsgroups for that kind of discussion. Science is about more than just using your current tools. -- "Also . . . I can kill you with my brain." River Tam, Trash, Firefly |
#26
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Towards routine, reusable space launch.
Jeff Findley schrieb:
In article , droleary@ 2017usenet1.subsume.com says... For your reference, records indicate that Jeff Findley wrote: Balloon launch isn't worth the trades which have to be made, IMHO. Certainly not today, no, or people would be doing it. But as I keep saying, new technologies keep popping up all the time that might make it viable in the future, at least for a few use cases. I have an engineering degree. So do I (PhD in chemical engineering). When developing new things, engineers work with what they have today because they've got schedules and deadlines to meet. The world would be a poorer place if that was the case. You're talking about technologies not yet invented. That's research, not development. The two are not the same. How would you classify chemical process development? Seems that, according to your defiinition, I am doing more research than I thought :-) |
#27
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Towards routine, reusable space launch.
Doc O'Leary wrote on Tue, 12 Jun
2018 14:36:47 -0000 (UTC): For your reference, records indicate that Jeff Findley wrote: Sure, sure, Star Trek style transporters with infinite range. I'll get right on that. No, you wont. But you apparently *will* use it as a straw man to avoid actually addressing the likelihood that new technologies developed in the future will change the economies of space launches. Hell, thats essentially what SpaceX is demonstrating today. Nope. SpaceX is using OLD technologies in slightly new ways. That's what engineers do. What you're talking about is, well, what loons do. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
#28
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Towards routine, reusable space launch.
Doc O'Leary wrote on Tue, 12 Jun
2018 15:00:13 -0000 (UTC): For your reference, records indicate that Fred J. McCall wrote: Doc O'Leary wrote on Mon, 11 Jun 2018 22:35:20 -0000 (UTC): Chicken and egg. The fact is that we *do* sometimes have to elaborately engineer spacecraft in order to make them small enough to fit into a nose cone or payload bay of a rocket. Head and ass. Cite for such payloads? Be specific. You're posting into a 'sci' newsgroup. Handwavium is not sufficient. Then I must say I note a lack of citations for your own claims. I haven't made any claims. Mine are easy enough to demonstrate. I can literally link to just about *any* payload that unfolds to deploy as evidence. Lets start with the obvious: https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#/media/File:JWST_launch_configuration.png Not a good example. Things like solar arrays are launched folded because they can't take acceleration without snapping off, not because they're 'too bulky'. Try again? A different launch vehicle/process might allow us more flexibility when it comes to approaching those very real problems. What 'very real problems' would those be? Asked and answered. Your willful ignorance is not compelling. I only asked it once and you never answered. Claim fails. We're constrained by the real world. Magic materials are right out. Straw man. All I?m saying is that it?s foolish to completely discount new technologies simply because they?re not the rockets you know so well from the past. Go look up what 'straw man' means. It manifestly does NOT mean pointing out reality. Then you need to look up the definition yourself, because I did not suggest anything magical. I simply made note of the fact that new technologies come along all the time. In light of that, it is foolish to be so dismissive of anything but rockets as launch vehicles for all stages of space travel. It is foolish NOT to be dismissive of airy claims for 'magic' justified by handwavium. You are in the wrong newsgroup. Cite some of these 'new technologies' and what it takes for them to work. Be specific. You're crossposting into a 'sci' newsgroup. Handwavium is not sufficient. It actually is. My argument is not *for* any one technology. It is simply that rockets have obvious limits, have inherent inefficiencies, and its worthwhile to keep our options open when it comes to thinking about different ways to get things into orbit and beyond. No, it actually isn't. Congratulations on demonstrating that you don't know **** about either science or engineering. What do you propose to replace rockets with, other than 'magic'? You continue to build this same straw man. Dont be a dick. Please save your thread****ting for Facebook or Twitter. You continue to flap your arms and make chicken noises, insisting you can fly to the Moon that way. Don't be a dip****. You are in the wrong newsgroup. -- "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 |
#29
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Towards routine, reusable space launch.
Doc O'Leary wrote on Tue, 12 Jun
2018 15:20:22 -0000 (UTC): For your reference, records indicate that Jeff Findley wrote: I have an engineering degree. When developing new things, engineers work with what they have today because they've got schedules and deadlines to meet. You're talking about technologies not yet invented. That's research, not development. The two are not the same. I never claimed they were. Actually you are, but you're too thick to recognize the implications of your position. The topic of the thread is *not* what can I build today, its Towards routine, reusable space launch. That has nothing to do with todays technology, and nobody has made the case that continued use of rockets (even reusable ones) can make it happen. You're not going to move "towards routine, reusable space launch" with technologies that you CANNOT build today and that you cannot even describe a scientific theoretical basis for. It has EVERYTHING to do with today's technology and if you think there's something other than rockets, either trot it out or STFU. Two different sets of requirements lead to two completely different vehicles. That's how engineering optimization works. Indeed. Which is why I argue that rockets alone are unlikely to be the only path to space. And they *definitely* are not the path to deep space. Right now there IS no path to 'deep space'. It's sad, but get over it. What you are trying to get me to admit is that eventually, some day, there may be something better. Sure, there might. Also, monkeys might fly out of my butt. Really? You think new technologies are butt-monkeys unlikely? Then lets get you retired, man, because you are *not* allowing your field to innovate nearly as much as it needs to. He thinks that your 'magic' technology that breaks the laws of physics is "butt-monkeys unlikely". I agree with him. So does anyone sane with any knowledge of science and engineering. I'm not waiting for sci-fi to become reality. I'm working with what I've got today. Again, that's what engineers do. Then you should be looking in engineering newsgroups for that kind of discussion. Science is about more than just using your current tools. I don't think you know what science is. What it is NOT is airy speculation about 'new magic' in the sweet by and by. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
#30
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Towards routine, reusable space launch.
Thomas Koenig wrote on Tue, 12 Jun 2018
19:43:04 -0000 (UTC): Jeff Findley schrieb: In article , droleary@ 2017usenet1.subsume.com says... For your reference, records indicate that Jeff Findley wrote: Balloon launch isn't worth the trades which have to be made, IMHO. Certainly not today, no, or people would be doing it. But as I keep saying, new technologies keep popping up all the time that might make it viable in the future, at least for a few use cases. I have an engineering degree. So do I (PhD in chemical engineering). That's nice. What would be your reaction if I speculated about a chemical with 'magic' properties that could be used to build a space tether here on Earth (I say 'magic' because it requires more strength in tension than is theoretically possible)? When developing new things, engineers work with what they have today because they've got schedules and deadlines to meet. The world would be a poorer place if that was the case. That IS the case. You're a chemical engineer. When you need to design a new industrial process to produce some chemical, do you run off and try to pull something out of your ass or do you start with known reaction pathways and mechanisms? You're talking about technologies not yet invented. That's research, not development. The two are not the same. How would you classify chemical process development? Seems that, according to your defiinition, I am doing more research than I thought :-) You're certainly doing SOME research, but I assume what you're doing is trying to come up with ways to optimize known reaction pathways so that the one you want 'wins'. In other words, you're starting with what you know today rather than postulating some undiscovered chemical reaction. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
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