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#11
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Towards routine, reusable space launch.
On 6/11/2018 11:36 AM, Thomas Koenig wrote:
Jeff Findley schrieb: By your definition, a passenger carrying aircraft is "waste" because it flies from one destination to another while carrying passengers. Of course. Firing passengers from large-caliber guns generates much less waste, obviously, and should be the preferred solution :-) perhaps the passengers should walk. |
#12
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Towards routine, reusable space launch.
On 6/11/2018 3:02 PM, Sergio wrote:
On 6/11/2018 11:36 AM, Thomas Koenig wrote: Jeff Findley schrieb: By your definition, a passenger carrying aircraft is "waste" because it flies from one destination to another while carrying passengers. Of course. Firing passengers from large-caliber guns generates much less waste, obviously, and should be the preferred solution :-) perhaps the passengers should walk. Correct me if I'm wrong, Sergio, But then they would be "pedestrians" rather than passengers, right? |
#13
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Towards routine, reusable space launch.
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. -- "Also . . . I can kill you with my brain." River Tam, Trash, Firefly |
#14
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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 03:16:38 -0000 (UTC): Like I said, it might not *currently* be viable, but as an alternative technology it brings new sets of trade-offs to the table such that a few tweaks here and there might make it viable for certain kinds of launches (e.g., bulky items that are hard to make aerodynamically efficient benefit from starting at the highest possible altitude). And just what such items do we send to space? 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. A different launch vehicle/process might allow us more flexibility when it comes to approaching those very real problems. 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. Hope for bigger things. I fully believe that, for a society to be advanced enough to make a space elevator project realistic, its value would be more incremental than revolutionary. Rockets are the best we have right now, but were stuffed if thats the best we can do. Just why are we 'stuffed'? Be specific. Because rockets have only taken humans as far as the Moon, but we haven’t gone to the Moon in decades, and we’ll likely see all the people who *have* been to the Moon dead before we ever return there. *Maybe* the promise of a Mars colony is achievable with rockets, but probably not in the lifetime of anyone walking on Earth today. And even in 1000 lifetimes, rockets aren’t going to take us to explore another planet around another star. -- "Also . . . I can kill you with my brain." River Tam, Trash, Firefly |
#15
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Towards routine, reusable space launch.
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. 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. 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. 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. -- "Also . . . I can kill you with my brain." River Tam, Trash, Firefly |
#16
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Towards routine, reusable space launch.
Thomas Koenig wrote:
Jeff Findley schrieb: By your definition, a passenger carrying aircraft is "waste" because it flies from one destination to another while carrying passengers. Of course. Firing passengers from large-caliber guns generates much less waste, obviously, and should be the preferred solution :-) Bobble tech doesn't bother with the guns. Just encapsulate then blow a nuke nearby. -- We are geeks. Resistance is voltage over current. |
#17
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Towards routine, reusable space launch.
On 6/11/2018 4:23 PM, benj wrote:
On 6/11/2018 3:02 PM, Sergio wrote: On 6/11/2018 11:36 AM, Thomas Koenig wrote: Jeff Findley schrieb: By your definition, a passenger carrying aircraft is "waste" because it flies from one destination to another while carrying passengers. Of course. Firing passengers from large-caliber guns generates much less waste, obviously, and should be the preferred solution :-) perhaps the passengers should walk. Correct me if I'm wrong, Sergio, But then they would be "pedestrians" rather than passengers, right? you are right, again. Unless you consider them as "shoe" passengers, ugh. or if they were bundled together, like a tour group |
#18
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Towards routine, reusable space launch.
Doc O'Leary wrote on Mon, 11 Jun
2018 22:18:30 -0000 (UTC): 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. Thats just the problem: youre 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. Yes, if you postulate the existence of magic everything gets much easier. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
#19
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Towards routine, reusable space launch.
Doc O'Leary wrote on Mon, 11 Jun
2018 22:35:20 -0000 (UTC): For your reference, records indicate that Fred J. McCall wrote: Doc O'Leary wrote on Mon, 11 Jun 2018 03:16:38 -0000 (UTC): Like I said, it might not *currently* be viable, but as an alternative technology it brings new sets of trade-offs to the table such that a few tweaks here and there might make it viable for certain kinds of launches (e.g., ?bulky? items that are hard to make aerodynamically efficient benefit from starting at the highest possible altitude). And just what such items do we send to space? 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. 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? 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. 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. Hope for bigger things. I fully believe that, for a society to be advanced enough to make a space elevator project realistic, it?s value would be more incremental than revolutionary. Rockets are the best we have right now, but we?re stuffed if that?s the best we can do. Just why are we 'stuffed'? Be specific. Because rockets have only taken humans as far as the Moon, but we havent gone to the Moon in decades, and well likely see all the people who *have* been to the Moon dead before we ever return there. *Maybe* the promise of a Mars colony is achievable with rockets, but probably not in the lifetime of anyone walking on Earth today. And even in 1000 lifetimes, rockets arent going to take us to explore another planet around another star. So, not 'stuffed' at all, then. As I thought. What do you propose to replace rockets with, other than 'magic'? -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
#20
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Towards routine, reusable space launch.
Doc O'Leary wrote on Mon, 11 Jun
2018 22:50:22 -0000 (UTC): 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. Certainly not tomorrow or the next day, either. Just what are these magical "new technologies" that keep "popping up all the time"? 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 its (arguably) the least wasteful mode of transportation we currently have says nothing about how we might travel in the future. If you want to talk about "how we might travel in the future", you need to come up with some suggestions (that aren't PFM). 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 airplanes dominance. Nope. Ships and trains went 'there and back', too. Logic really isn't your strong suit, is it? 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. In other words, you're postulating some unspecified 'magic'. You're posting into the wrong newsgroup. See the 'sci' at the front? That means SCIENCE. That means you can't just wave your arms and fly to the Moon. You have to actually put forward the scientific basis for why you can do so. 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 Im just wondering why you cant 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 its like you werent really thinking about what your words actually meant. Because this is a SCIENCE newsgroup, you ****! Yes, magic would be nice. We don't have it and never will. Get over it. -- "Ordinarily he is insane. But he has lucid moments when he is only stupid." -- Heinrich Heine |
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