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"Pat Flannery" wrote in message
... Also, this technology would be hard pressed to defeat a High G Acceleration/Short Burn Time solid-fueled missile (like a surface-to-surface variant of the Sprint), as the motor burn would be over before the aircraft could detect, target, and engage it effectively. The thick motor casing of a solid-fuel missile of any sort would mean that the laser would have a hard time heating its contents in comparison to the thin tank walls of a liquid-fueled missile. Perhaps burning through the casing would be feasible at a distance. |
#22
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Pat Flannery wrote
Now that's interesting...it implies that they assume that the missiles they are going to be shooting at are liquid-fueled. Yes, but much of the current TBM threat is composed of Scud-like liquid-fueled missiles, so that's ok. I wonder how long of a laser illumination they need to destroy a solid-fueled one? Also, this technology would be hard pressed to defeat a High G Acceleration/Short Burn Time solid-fueled missile (like a surface-to-surface variant of the Sprint), as the motor burn would be over before the aircraft could detect, target, and engage it effectively. The thick motor casing of a solid-fuel missile of any sort would mean that the laser would have a hard time heating its contents in comparison to the thin tank walls of a liquid-fueled missile. It isn't clear that the ABL Mod 1 is intended to defeat things like the SS-21 or M-9/M-11, all of which are harder and burn faster than Scudish missiles. Perhaps that's for Mod 2 and beyond. |
#23
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In sci.space.policy Neil Gerace wrote:
"Pat Flannery" wrote in message ... Also, this technology would be hard pressed to defeat a High G Acceleration/Short Burn Time solid-fueled missile (like a surface-to-surface variant of the Sprint), as the motor burn would be over before the aircraft could detect, target, and engage it effectively. The thick motor casing of a solid-fuel missile of any sort would mean that the laser would have a hard time heating its contents in comparison to the thin tank walls of a liquid-fueled missile. Perhaps burning through the casing would be feasible at a distance. A really neat idea comes to me. On the front of a liquid fuelled rocket, you put a heat exchanger, and run the fuel through it first. Add some really big jettisonable aero surfaces, so that it can point accurately at the laser, jettison the aero surfaces. Ride the beam in. |
#24
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Allen Thomson wrote: Pat Flannery wrote Now that's interesting...it implies that they assume that the missiles they are going to be shooting at are liquid-fueled. Yes, but much of the current TBM threat is composed of Scud-like liquid-fueled missiles, so that's ok. At the moment, yes...but what about the timeframe when this system becomes operational...say in ten years or so? It isn't clear that the ABL Mod 1 is intended to defeat things like the SS-21 or M-9/M-11, all of which are harder and burn faster than Scudish missiles. Perhaps that's for Mod 2 and beyond. The Russians laser armored their SS-18 mod 5 according to this: http://www.astronautix.com/lvs/r36m2.htm Putting polyurethane foam over the rocket body would mean that the laser would have to burn it off before heating the structure of the missile's fuel tanks. Two other techniques come immediately to mind for defeating laser attack on a missile; spinning it on it's axis to spread the illumination over a wider area, and enveloping the missile in a smoke cloud during ascent via a smoke generator on its nose. The laser would heat the smoke, not the missile's body. Pat |
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Ian Stirling wrote: A really neat idea comes to me. On the front of a liquid fuelled rocket, you put a heat exchanger, and run the fuel through it first. Add some really big jettisonable aero surfaces, so that it can point accurately at the laser, jettison the aero surfaces. Ride the beam in. Hey, I _like_ that! They wouldn't be expecting that, would they? Kim Jong-Il |
#26
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Pat Flannery wrote: Allen Thomson wrote: Pat Flannery wrote Now that's interesting...it implies that they assume that the missiles they are going to be shooting at are liquid-fueled. Yes, but much of the current TBM threat is composed of Scud-like liquid-fueled missiles, so that's ok. At the moment, yes...but what about the timeframe when this system becomes operational...say in ten years or so? It isn't clear that the ABL Mod 1 is intended to defeat things like the SS-21 or M-9/M-11, all of which are harder and burn faster than Scudish missiles. Perhaps that's for Mod 2 and beyond. The Russians laser armored their SS-18 mod 5 according to this: http://www.astronautix.com/lvs/r36m2.htm Putting polyurethane foam over the rocket body would mean that the laser would have to burn it off before heating the structure of the missile's fuel tanks. If part of the polyurethane foam is burned off, wouldn't that make the missile's mass distribution asymetrical? I think that'd chinger the missile as the thrust vector needs to point through center of mass. Two other techniques come immediately to mind for defeating laser attack on a missile; spinning it on it's axis to spread the illumination over a wider area, and enveloping the missile in a smoke cloud during ascent via a smoke generator on its nose. The laser would heat the smoke, not the missile's body. How about a highly reflective, mirror surface? Reflectors on bicycles or roadside warning signs employ three sets of mirror fragments, each set perpendicular to the other two. Looking into a triplet of mirror fragments would be like looking into a box corner. Any beam hitting such a corner is bounced back in the direction it came. Pat -- Hop David http://clowder.net/hop/index.html |
#27
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On the front of a liquid fuelled rocket, you put a heat exchanger, and run the fuel through it first. Add some really big jettisonable aero surfaces, so that it can point accurately at the laser, jettison the aero surfaces. Ride the beam in. The ABL isn't a continuous-fire weapon, it fires short bursts. Not long enough for something to home in on. The 'rangefinding' laser paints the target for a longer period before the weapon fires, but I doubt even that is long enough. Eric P. |
#28
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Eric Pawtowski wrote:
On the front of a liquid fuelled rocket, you put a heat exchanger, and run the fuel through it first. Add some really big jettisonable aero surfaces, so that it can point accurately at the laser, jettison the aero surfaces. Ride the beam in. The ABL isn't a continuous-fire weapon, it fires short bursts. Not long enough for something to home in on. Sorry, but that's hogwash. If you can get the instantaneous direction of the incoming pulse, then the same for several following pulses, then you can derive the track of the firing unit by working from that data. If you can derive the track, you can send a weapon to intercept. D. -- Touch-twice life. Eat. Drink. Laugh. -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL |
#29
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Pat Flannery wrote:
Allen Thomson wrote: Pat Flannery wrote Now that's interesting...it implies that they assume that the missiles they are going to be shooting at are liquid-fueled. Yes, but much of the current TBM threat is composed of Scud-like liquid-fueled missiles, so that's ok. At the moment, yes...but what about the timeframe when this system becomes operational...say in ten years or so? Probably still liquids as big solids are difficult to do. Even if the threat vehicle is solid fueled, burning a hole in the side of it will do it no favors. The Russians laser armored their SS-18 mod 5 according to this: http://www.astronautix.com/lvs/r36m2.htm Mark needs to change his drug dosages. Putting polyurethane foam over the rocket body would mean that the laser would have to burn it off before heating the structure of the missile's fuel tanks. Handwaving away the problems of keeping the foam in place, and of the weight of the foam. Two other techniques come immediately to mind for defeating laser attack on a missile; spinning it on it's axis to spread the illumination over a wider area, Handwaving away the enourmous problems this causes in guidance. and enveloping the missile in a smoke cloud during ascent via a smoke generator on its nose. The laser would heat the smoke, not the missile's body. Hanwaving away the problem of creating a dense enough smoke cloud. Pat; stick to cute personality filled monkeys. At least there you have a clue what you are talking about. D. -- Touch-twice life. Eat. Drink. Laugh. -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL |
#30
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Hop David writes:
Wishlist of Pinky and the Brain (aka Bush and the Cheney): http://www.newamericancentury.org/Re...asDefenses.pdf From page 53: "... Similarly, a fifth component of a theater-wide network of ballistic missile defenses, the Air Forces airborne laser project, has suffered from insufficient funding. This system, which mounts a high energy laser in a 747 aircraft, is designed to intercept theater ballistic missiles in their earliest, or boost phase, when they are most vulnerable." A 747 aircraft!? Wouldn't this be a sitting duck for swarms of even primitive SAM's? But I'd guess the authors of this paper consulted military engineers more competent than I. Yes. Yes they did. First off, they consulted engineers who told them that primitive SAMs, and even most very sophisticated SAMs, have a maximum range of a few dozen miles, and that most SAM operators have only enough of them to defend point targets rather than to deploy impenetrable SAM belts several hundred miles wide. The ABL having a design range of several hundred miles, it can stand off beyond the range of enemy defenses and still shoot down enemy missiles in boost phase. If they could make this work, it would be useful for more than taking theater ballistic missiles out in their boost phase. Yes. For example, it would be useful for taking out surface-to-air missiles in their boost phase. This also argues agains the system being a sitting duck to primitive, or sophisticated, SAMs. You launch a SAM at it, the SAM explodes. Repeat until out of SAMs, or clued in to the futility of the strategy. On page 259 of his book _How The World Was One_, Arthur C. Clarke quotes Rajiv Gandhi, then Prime Minister of India: And, apparently, a competent military engineer? I did not know that. "Today, Professor Clarke has given us many more reasons why it is not a peace weapon or peace shield, but perhaps a new 'Project Damocles' as he has called it. India and the Six Nation Initiative have worked with the Non-Aligned Movement and many other nations against increases in the arms race, against this delusion of a shield and this delusion of the defensive nature of the SDI. As Professor Clarke has said, lasers which can destroy very-rapidly-moving missiles in fractions of a second can be used very effectively against stationary or very-slow-moving targets. In fact the SDI could well turn into a new, very-high-technology weapon." Oh my gosh! SDI would involve *new high technology weapons*! Alert the presses! Dastardly military-industrial-complex Secret Plot(tm) exposed! And using it against stationary or slow-moving targets? Certainly it *could* do that, but who cares? We already have lots of weapons which can destroy stationary or slow-moving targets, and which unlike lasers can pierce heavy steel or reinforced concrete to do so. ABL cannot pierce a simple brick wall, nor even the morning fog. -- *John Schilling * "Anything worth doing, * *Member:AIAA,NRA,ACLU,SAS,LP * is worth doing for money" * *Chief Scientist & General Partner * -13th Rule of Acquisition * *White Elephant Research, LLC * "There is no substitute * * for success" * |
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