Don't forget, it was W's dad who wanted to turn the peace dividend into the Space Exploration Initiative (http://www.abo.fi/~mlindroo/Station/Slides/sld049 a.htm & http://history.nasa.gov/staffordrep/main_toc.PDF ). Whether you believe this was for the good of the nation or to keep money in the pocket of defense companies, they still wanted to do big things in space (amazingly if you read his stuff, Dan Quayle of all people really had some good ideas about our future in space). The whole thing was snubbed by their political opponents (and I don't think they have forgoten that, look for O'Keefe to clean some house) and NASA was kept as a space bus operator. I wouldn't be surpised if we get some new version of the SEI proposed in a possible 2nd Bush term (especially if the war on terror is winding down and another "peace dividend" is approaching).
The SSME? are you nuts? The SSME is far too complicated for what it needs to be with current technology. I agree that it is nice to take an evolutionary approach to rocket engine design, so that your reliability stays high, but IF we stay with H2 as the fuel it would certainly be worthwhile to go to something like an SSME 2:the sequel. Redesign it with current materials and manufacturing technology. Greatly reduce the part count to reduce failure modes. And, of course, take into account lessons learned on the Classic SSME. That assumes we stay with H2. Kerosene is still not dead, and might be the better choice. ISP is lower, but so is tankage. I'm not saying anything new, of course; just making the point that we don't want to stick with the current SSME.
Oribtal's Solution
on
Redirecting NASA
·
· Score: 4, Interesting
At this year's Joint Propulsion Conference, there was a session where NASA and several contractors discussed the Space Launch Initiative and thier plans. All but one of the talks centered around building completely reusable vehicles as per the SLI plan. Oribtal's talk (I think partially drawn from space economics work from William R. Claybaugh, II) was different. They showed that at currently projected rates, you could get something like 800% of the operational cost savings of the SLI program with only a tiny fraction of the research and capital costs just by developing a reusable crew vehicle (like a new and improved X-38) and putting that on top of the EELVs Lockheed-Martin and Boeing have already developed (which are not yet man-rated, but given their design reliability that should be a relatively small step compared with developing a totally new launch system). In addition to having lower R&D and capital costs, it should have less risk too. 80% savings for much less risk and capital looks very very good until you get up to launch rates of around 1/week.
This may not be a sexy as SLI, but the economics seem better. Despite people's attraction to SLI, we won't get to Mars and back to the moon any time soon if we waste our finite resources on big systems that we don't yet need (no matter how cool they look). Better to spend that money on R&D or systems engineering so that we can move the market closer to that 1 launch/week and so that when we do need to build the next big thing, it is done with even better technology.
Chris Y. Taylor
I'd rather think of myself as...
on
Generation Wrecked
·
· Score: 5, Funny
"What the US does is goes into a country overthows it's government and tells the people that we will only stop bombarding the country if they take on a capitalistic democratic style government."
I like how this post makes it sound like there are CIA agents, State Dept. officials and soldiers going around to the subsitance farmers, shopkeepers, etc. of these countries and saying "You'd better stop being oppressed and impovrished or we'll have to come back here and bust some heads." Apparently some people can't distinguish between the claims of the thugs and warlords who run (I hesitate to say "lead") some of these countries from the desires of the general population. Countries are not individual organisms. And if the people of a country really want to have someone come and steal their property, then I suppose they can elect someone to do that under a democratic gov't just as easily as they could install one as dictator.
The article at washington.edu about Zubrin's nuke designs says:
"He has used a simplified model to show that the distribution of fission-inducing thermal neutrons in the reaction chamber depends critically on the velocity of the liquid fuel as it passes through the reaction chamber. This dependence occurs because the moving salt water fuel is also the medium in which the neutrons are slowed. If the liquid is at rest, the maximum flux occurs at the center of the cylinder, but if the moderating fuel liquid is in motion, the point of maximum flux is skewed downstream and also rises to a much higher maximum. If the right fuel velocity is chosen, the thermal neutron flux (and therefore the site of maximum fission energy release) can be made to peak very sharply just outside the exit end of the cylindrical reaction chamber."
That is true only when the system is operating at a steady state condition. This means that, as with liquid fuel rockets, starting and shutting down the engine is going to be a difficult trick. It might be accomplished using a chemical shim to inhibit the nuclear reaction duirng startup and shutdown, but that is probably the sort of thing that would need experimental testing to prove (I don't trust computer models quite that much).
"I think the idea is that you don't want to suddenly accelerate things toward you, that would sort of suck"
I think that would literally suck. Dr. Podklentov reports, however, that his impulse gravity generator "pushes" on objects not "pulls." You don't have to worry about pulling debris into the emitter.
Also, it is reported to penetrate bulk matter and act on all types of matter with the same acceleration (just like gravity, hence the "gravity" in impulse gravity generator). The portion of the object in the beam path would experience NO internal stresses from that, just like an object in freefall may be accellerating rapidly, but because every part of it is accelerating the same there are no internal stresses. What might get destructive is where you have only a portion of the target in the beam, causing high internal stesses at that intersection. The portion in the beam undergoes high accleration, and the rest of the target does not; the beam takes a "core sample" out of any delicate components of the target in beam path. This is actually something you want to be careful to avoid when using the beam for propulsion. Current technology is so inefficient right now (and might have pointing accuracy limitations), however, that a gravitic ray is not likely to replace more conventional weapons in the near future.
Chris Y Taylor http://www.gravity-society.org/abstract_AI AA.htm
They really meant "gees". It is not a unit of force, it is a unit of acceleration (roughly 32ft/s^2 or 9.8m/s^2). Multiplied by the mass of the portion of the target in the beam path, this gives you units of force.
The Space.com's article quotes Boeing's press release as stating:
GRASP is not a codename for a current project but rather an acronym for a presentation entitled "Gravity Research for Advanced Space Propulsion," in which a Boeing engineer explains Podkletnov's theory and proposes that we should continue to monitor this work and perhaps even conduct some low-cost experiments.
I suspect that this internal Boeing presentation was the result of my presenation of a paper by Dr. Modanese and myself entitled "EVALUATION OF AN IMPULSE GRAVITY GENERATOR BASED BEAMED PROPULSION CONCEPT" (http://www.gravity-society.org/abstract_AIAA.htm) at the 38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference earlier this year. I don't know who all attended my talk, but there were Boeing guys all over the conference, so I wouldn't be surprised if I had a few in the audience. Copies of the paper are available from the AIAA. Dr. Modanese may post a copy it on the internet at www.gravity-society.org soon. The ESA also released a report on the implications of Dr. Podkletnov's research for aerospace called "Gravity control and possible influence on space propulsion: a scientific study" that may have contribued to Boeing's internal GRASP presentation. I don't know where you can get a copy of the ESA's study.
You are right. I don't know where the "high speed" bit came from, whether it is Boeing or Jane's idea, but it is incorrect. The destruction would also probably only happen if part of the object were in the superraygunofinstantgravitationaldeath's beam path and part was not. Otherwise the object would be acclerated but would likely experience little or no internal stresses. Good catch.
Chris Y. Taylor http://www.gravity-society.org/abstract_AI AA.htm
"does anyone have any insight as to what impact it would have purely on an engineering level?"
Yes. See AIAA Paper #2002-4095, "Evaluation of an Impulse Gravity Generator Based Beamed Propulsion Concept" from this year's Joint Propulsion Conference.
Sales, sure. Licensing royalties might be a problem, at least for the propulsion applications that have already been described in preivously published works.
The timing of this report is curious, as it comes about a month after this year's Joint Propulsion conference, where I gave a presentation on the paper "Evaluation of an Impulse Gravity Generator Based Beamed Propulsion Concept" (AIAA Paper 2002-4095) discussing aerospace propulsion applications of Dr. Podkletnov's latest work. Now Boeing leaks to Janes that they have a Gravity Research for Advanced Space Propulsion project to investigate aerospace propulsion applications of Dr. Podkletnov's latest work (see http://www.sky.com/skynews/article/0,,31500-120604 72,00.html ). Either they are rushing to get on the bandwagon, or they have some guys at Phantom Works who are p!$$ed off that they weren't permitted to publish their ideas first.
Lets forget these paper bills altogether. If we want to make our money more interesting and easier to distinguish, we should just start using giant round rocks with holes in the middle.
"It is true that several nations are deploying such ground radar systems in an attempt to defeat stealthy aircraft."
Good for them. The more money the spend trying to see our planes, the less money they are spending on other defense expenditures. As long as their efforts cost more (in %GNP) than building low observable features into the plane cost us, we come out ahead.
And BTW, it is "low observable" not "unobservable". Even the B-2 isn't invisible; it is just difficult to find. But the media likes to sensationalize stuff, and "invisible airplane" obviously sounds too cool for them to pass up.
Based on the wide range of quotes and links you cite, I'd say it appears that plenty of people have talked about the Russian contribution to the design. A lot more than most subcontractors can expect, other than engine mfg.
Slashdot Mirror
Don't forget, it was W's dad who wanted to turn the peace dividend into the Space Exploration Initiative (http://www.abo.fi/~mlindroo/Station/Slides/sld049 a.htm & http://history.nasa.gov/staffordrep/main_toc.PDF ). Whether you believe this was for the good of the nation or to keep money in the pocket of defense companies, they still wanted to do big things in space (amazingly if you read his stuff, Dan Quayle of all people really had some good ideas about our future in space). The whole thing was snubbed by their political opponents (and I don't think they have forgoten that, look for O'Keefe to clean some house) and NASA was kept as a space bus operator. I wouldn't be surpised if we get some new version of the SEI proposed in a possible 2nd Bush term (especially if the war on terror is winding down and another "peace dividend" is approaching).
"something like 800% of the operational cost savings"
Obviously, that should read 80%, not 800!
The SSME? are you nuts? The SSME is far too complicated for what it needs to be with current technology. I agree that it is nice to take an evolutionary approach to rocket engine design, so that your reliability stays high, but IF we stay with H2 as the fuel it would certainly be worthwhile to go to something like an SSME 2:the sequel. Redesign it with current materials and manufacturing technology. Greatly reduce the part count to reduce failure modes. And, of course, take into account lessons learned on the Classic SSME. That assumes we stay with H2. Kerosene is still not dead, and might be the better choice. ISP is lower, but so is tankage. I'm not saying anything new, of course; just making the point that we don't want to stick with the current SSME.
At this year's Joint Propulsion Conference, there was a session where NASA and several contractors discussed the Space Launch Initiative and thier plans. All but one of the talks centered around building completely reusable vehicles as per the SLI plan. Oribtal's talk (I think partially drawn from space economics work from William R. Claybaugh, II) was different. They showed that at currently projected rates, you could get something like 800% of the operational cost savings of the SLI program with only a tiny fraction of the research and capital costs just by developing a reusable crew vehicle (like a new and improved X-38) and putting that on top of the EELVs Lockheed-Martin and Boeing have already developed (which are not yet man-rated, but given their design reliability that should be a relatively small step compared with developing a totally new launch system). In addition to having lower R&D and capital costs, it should have less risk too. 80% savings for much less risk and capital looks very very good until you get up to launch rates of around 1/week.
This may not be a sexy as SLI, but the economics seem better. Despite people's attraction to SLI, we won't get to Mars and back to the moon any time soon if we waste our finite resources on big systems that we don't yet need (no matter how cool they look). Better to spend that money on R&D or systems engineering so that we can move the market closer to that 1 launch/week and so that when we do need to build the next big thing, it is done with even better technology.
Chris Y. Taylor
http://www.inthe80s.com/dynamic/child8e.shtml
Why do you think they are called the "me generation"?
It sounds like Tale Spin to me.
"Shoot them... alot!" - Don Carnage
"What the US does is goes into a country overthows it's government and tells the people that we will only stop bombarding the country if they take on a capitalistic democratic style government."
I like how this post makes it sound like there are CIA agents, State Dept. officials and soldiers going around to the subsitance farmers, shopkeepers, etc. of these countries and saying "You'd better stop being oppressed and impovrished or we'll have to come back here and bust some heads." Apparently some people can't distinguish between the claims of the thugs and warlords who run (I hesitate to say "lead") some of these countries from the desires of the general population. Countries are not individual organisms. And if the people of a country really want to have someone come and steal their property, then I suppose they can elect someone to do that under a democratic gov't just as easily as they could install one as dictator.
The article at washington.edu about Zubrin's nuke designs says:
"He has used a simplified model to show that the distribution of fission-inducing thermal neutrons in the reaction chamber depends critically on the velocity of the liquid fuel as it passes through the reaction chamber. This dependence occurs because the moving salt water fuel is also the medium in which the neutrons are slowed. If the liquid is at rest, the maximum flux occurs at the center of the cylinder, but if the moderating fuel liquid is in motion, the point of maximum flux is skewed downstream and also rises to a much higher maximum. If the right fuel velocity is chosen, the thermal neutron flux (and therefore the site of maximum fission energy release) can be made to peak very sharply just outside the exit end of the cylindrical reaction chamber."
That is true only when the system is operating at a steady state condition. This means that, as with liquid fuel rockets, starting and shutting down the engine is going to be a difficult trick. It might be accomplished using a chemical shim to inhibit the nuclear reaction duirng startup and shutdown, but that is probably the sort of thing that would need experimental testing to prove (I don't trust computer models quite that much).
Chris Y Taylor
http://www.pbm.com/~lindahl/real.programmers.html
I prefer the term "kook".
If any such papers actually lead to a functioning propulsion system, of course, they then become "breakthrough propulsion physics".
Chris Y Taylor
... doesn't mean that I'm not.
Chris Y. Taylor
"I think the idea is that you don't want to suddenly accelerate things toward you, that would sort of suck"
I AA.htm
I think that would literally suck. Dr. Podklentov reports, however, that his impulse gravity generator "pushes" on objects not "pulls." You don't have to worry about pulling debris into the emitter.
Also, it is reported to penetrate bulk matter and act on all types of matter with the same acceleration (just like gravity, hence the "gravity" in impulse gravity generator). The portion of the object in the beam path would experience NO internal stresses from that, just like an object in freefall may be accellerating rapidly, but because every part of it is accelerating the same there are no internal stresses. What might get destructive is where you have only a portion of the target in the beam, causing high internal stesses at that intersection. The portion in the beam undergoes high accleration, and the rest of the target does not; the beam takes a "core sample" out of any delicate components of the target in beam path. This is actually something you want to be careful to avoid when using the beam for propulsion. Current technology is so inefficient right now (and might have pointing accuracy limitations), however, that a gravitic ray is not likely to replace more conventional weapons in the near future.
Chris Y Taylor
http://www.gravity-society.org/abstract_A
Snap.
rate of change of Snap is called Crackle.
rate of change of Crackle is called... can you guess it...
Pop.
I don't know what they are beyond that.
Chris Y Taylor
They really meant "gees". It is not a unit of force, it is a unit of acceleration (roughly 32ft/s^2 or 9.8m/s^2). Multiplied by the mass of the portion of the target in the beam path, this gives you units of force.
Chris Y Taylor
The Space.com's article quotes Boeing's press release as stating:
) at the 38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference earlier this year. I don't know who all attended my talk, but there were Boeing guys all over the conference, so I wouldn't be surprised if I had a few in the audience. Copies of the paper are available from the AIAA. Dr. Modanese may post a copy it on the internet at www.gravity-society.org soon. The ESA also released a report on the implications of Dr. Podkletnov's research for aerospace called "Gravity control and possible influence on space propulsion: a
GRASP is not a codename for a current project but rather an acronym for a presentation entitled "Gravity Research for Advanced Space Propulsion," in which a Boeing engineer explains Podkletnov's theory and proposes that we should continue to monitor this work and perhaps even conduct some low-cost experiments.
I suspect that this internal Boeing presentation was the result of my presenation of a paper by Dr. Modanese and myself entitled "EVALUATION OF AN IMPULSE GRAVITY GENERATOR BASED BEAMED PROPULSION CONCEPT" (http://www.gravity-society.org/abstract_AIAA.htm
scientific study" that may have contribued to Boeing's internal GRASP presentation. I don't know where you can get a copy of the ESA's study.
Chris Y Taylor
You are right. I don't know where the "high speed" bit came from, whether it is Boeing or Jane's idea, but it is incorrect. The destruction would also probably only happen if part of the object were in the superraygunofinstantgravitationaldeath's beam path and part was not. Otherwise the object would be acclerated but would likely experience little or no internal stresses. Good catch.
I AA.htm
Chris Y. Taylor
http://www.gravity-society.org/abstract_A
"does anyone have any insight as to what impact it would have purely on an engineering level?"
Yes. See AIAA Paper #2002-4095, "Evaluation of an Impulse Gravity Generator Based Beamed Propulsion Concept" from this year's Joint Propulsion Conference.
licensing royalties...
Sales, sure. Licensing royalties might be a problem, at least for the propulsion applications that have already been described in preivously published works.
The timing of this report is curious, as it comes about a month after this year's Joint Propulsion conference, where I gave a presentation on the paper "Evaluation of an Impulse Gravity Generator Based Beamed Propulsion Concept" (AIAA Paper 2002-4095) discussing aerospace propulsion applications of Dr. Podkletnov's latest work. Now Boeing leaks to Janes that they have a Gravity Research for Advanced Space Propulsion project to investigate aerospace propulsion applications of Dr. Podkletnov's latest work (see http://www.sky.com/skynews/article/0,,31500-120604 72,00.html ). Either they are rushing to get on the bandwagon, or they have some guys at Phantom Works who are p!$$ed off that they weren't permitted to publish their ideas first.
Just measure them both in radians, if it means that much. I'll stick with English.
A Jack, perhaps?
Lets forget these paper bills altogether. If we want to make our money more interesting and easier to distinguish, we should just start using giant round rocks with holes in the middle.
"It is true that several nations are deploying such ground radar systems in an attempt to defeat stealthy aircraft."
Good for them. The more money the spend trying to see our planes, the less money they are spending on other defense expenditures. As long as their efforts cost more (in %GNP) than building low observable features into the plane cost us, we come out ahead.
And BTW, it is "low observable" not "unobservable". Even the B-2 isn't invisible; it is just difficult to find. But the media likes to sensationalize stuff, and "invisible airplane" obviously sounds too cool for them to pass up.
Based on the wide range of quotes and links you cite, I'd say it appears that plenty of people have talked about the Russian contribution to the design. A lot more than most subcontractors can expect, other than engine mfg.