Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Wed, 25 Jul 2001, Steve Schear wrote: > Or reduce the effectiveness of the detection system by clandestinely > "salting" vessels entering our ports with radio active dust with the > same energy signatures. Sort of a radio active chaff. The point of a clandestine WOMD attack is that there is no forewarning. Salting random vehicles will make some people way more paranoid that they already are. As to nukes, according to anecdotal evidence (a single former employee), UPS doesn't screen for fissible signatures. I very much doubt they screen for vanilla HE (which, unless well packaged, emanate telltale volatiles, and contain a high nitrogen concentration, which you could probably detect with proper activation spectrocopy, unless *very* well shielded, or packed with a shipment of nitrate fertilizer). Screening devices are expensive, and have a limited processvity -- but technology marches on, of course. If a country would want to nuke a country with few 10..100 devices, it will get them into the country, and there's jack you can do about that. The probability of detection would be very, very low. The reason it's not being done is 1) no point 2) basic milk of human kindness. Sooner or later some random ijit or random group of ijits is going to fry/poison/infect a few people, which will have some serious impact on security policy, and the style of living where people concentrate. I hope I'm not there when it happens.
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Tue, 24 Jul 2001, Jim Choate wrote: > The optics used for focusing are NOT mirrors, they are (hopefully) Okay, a have a chemical laser, something which burns tons of fuel (deuterium/fluorine) in a second in a resonant cavity. It is hence a not very small cavity. The wavelength is IR, several microns. This is high-power optics with a giant aperture (because, you don't want your optics to suffer the fate of your target, and because the resonant cavity itself is huge). Lenses don't like giant fluxes, either. Even a ruby laser pulse can break optics, or the rod, if it has a blemish. Lenses are *HEAVY*. Lenses are not flexible, so you can't use them for tracking. Lenses don't do very well when we're talking about few um IR. So what that leaves you with is an active mirror optics. > transparent at the frequency under use. A mirror on the other hand is > required to be OPAQUE with respect to transmission, we want full, > 100%, reflectivity. That means that every photon that hits that mirror > interacts, loses some energy, and gets re-emitted. Jim, I fear that bullet accident you had took a chunk out of one of your frontal lobes. Or at least lead to a hemorrhage to a lesion in that area. Have you ever had a MRI screen done? I'm serious. > I have a half dozen lasers, thank you very much. -- Eugen* Leitl http://www.lrz.de/~ui22204/";>leitl __ ICBMTO : N48 10'07'' E011 33'53'' http://www.lrz.de/~ui22204 57F9CFD3: ED90 0433 EB74 E4A9 537F CFF5 86E7 629B 57F9 CFD3
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Tue, 24 Jul 2001, Eugene Leitl wrote: > On Mon, 23 Jul 2001, Jim Choate wrote: > > > Maybe. But even mirrors can be burned through by a laser. And then we've > > Jim, why are you trying so hard to make a complete fool out of yourself, > in a public forum? > > A chemical laser needs active optics to track your remote target. What do > you think that optics is made from, unobtainium? Do you understand basic > laws of optics? I recommend purchasing a 15 W laser (and a pair of > matching protection goggles), and then use it to ignite a match from a > close distance, and then over a few km, preferably during summer in your > native Texas. You could target the beam towards a projection wall, and > watch it with a pair of binoculars. It will be quite instructive. The optics used for focusing are NOT mirrors, they are (hopefully) transparent at the frequency under use. A mirror on the other hand is required to be OPAQUE with respect to transmission, we want full, 100%, reflectivity. That means that every photon that hits that mirror interacts, loses some energy, and gets re-emitted. I have a half dozen lasers, thank you very much. -- Nature and Nature's laws lay hid in night: God said, "Let Tesla be", and all was light. B.A. Behrend The Armadillo Group ,::;::-. James Choate Austin, Tx /:'/ ``::>/|/ [EMAIL PROTECTED] www.ssz.com.', `/( e\ 512-451-7087 -~~mm-'`-```-mm --'-
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Mon, 23 Jul 2001, Jim Choate wrote: > Maybe. But even mirrors can be burned through by a laser. And then we've Jim, why are you trying so hard to make a complete fool out of yourself, in a public forum? A chemical laser needs active optics to track your remote target. What do you think that optics is made from, unobtainium? Do you understand basic laws of optics? I recommend purchasing a 15 W laser (and a pair of matching protection goggles), and then use it to ignite a match from a close distance, and then over a few km, preferably during summer in your native Texas. You could target the beam towards a projection wall, and watch it with a pair of binoculars. It will be quite instructive. > got weight issues that this would entail. It's not like they've got a lot > of overhead for the job. I suspect that faceting wouldn't be any more > effective than a smoothly round body form, it could have aerodynamic > effects as well (ie sharp corners at the facet edges - and yes they could > be rounded - now you're moving back toward a round rocket planform). High albedo coating of the missile is *cheap*. Powerful lasers are that not, especially if you need to have several of them online in an area. -- Eugen* Leitl http://www.lrz.de/~ui22204/";>leitl __ ICBMTO : N48 10'07'' E011 33'53'' http://www.lrz.de/~ui22204 57F9CFD3: ED90 0433 EB74 E4A9 537F CFF5 86E7 629B 57F9 CFD3
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Mon, 23 Jul 2001, Jim Choate wrote: > Maybe. But even mirrors can be burned through by a laser. And then we've Jim, why are you trying so hard to make a complete fool out of yourself, in a public forum? A chemical laser needs active optics to track your remote target. What do you think that optics is made from, unobtainium? Do you understand basic laws of optics? I recommend purchasing a 15 W laser (and a pair of matching protection goggles), and then use it to ignite a match from a close distance, and then over a few km, preferably during summer in your native Texas. You could target the beam towards a projection wall, and watch it with a pair of binoculars. It will be quite instructive. > got weight issues that this would entail. It's not like they've got a lot > of overhead for the job. I suspect that faceting wouldn't be any more > effective than a smoothly round body form, it could have aerodynamic > effects as well (ie sharp corners at the facet edges - and yes they could > be rounded - now you're moving back toward a round rocket planform). High albedo coating of the missile is *cheap*. Powerful lasers are that not, especially if you need to have several of them online in an area. -- Eugen* Leitl http://www.lrz.de/~ui22204/";>leitl __ ICBMTO : N48 10'07'' E011 33'53'' http://www.lrz.de/~ui22204 57F9CFD3: ED90 0433 EB74 E4A9 537F CFF5 86E7 629B 57F9 CFD3
Re: Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
> My comment was limited to radiant energy weapons. As to those, the > critical vulnerability exists during launch and boost phase. The target is > slow, bright, large, has fuel on board and a nonarmored hull, which (as > other posters observed) can be weakened with enough flux. At least one of the propaganda articles said the kill mechanism was to make a hole in the hull near the fuel tank. High albedo may help the missile here as well as the warhead, though it's probably harder to deploy decoys at launch and boost phase than re-entry. > The demos are just that: demos. Given that a limited strike is best > conducted with remotely operated civilian aircraft, or plain old UPS, star > wars seems like effect of industrial lobby. The primary purpose of demos is to create public pressure to get increased funding, plus to remind the public that we still have a nuclear-war-industrial-complex that's Protecting Our Country Against Somebody, so in case EastAsia ever becomes a credible threat to Oceania, Our Brave Military will have the infrastructure to do something about it. Meanwhile of course, any foreign terrorist that wants to nuke the US with a physically small weapon only needs to pack it in cocaine and bring it in with the regular shipments, while Rogue Nations that can only make large Fat Boy style weapons need cruder methods, like bribing a crane operator to load the wrong container on a ship bound for New York or Los Angelese harbor. X-Authenticated-User: idiom ~~~ Thanks; Bill Stewart <[EMAIL PROTECTED]>
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
At 06:05 PM 7/23/2001 -0500, Jim Choate wrote: >On Mon, 23 Jul 2001, Steve Schear wrote: > > > >It's the one they use primarily. > > > > Only because the rocket exterior has not been "stealthed" via high > > reflectivity and faceting. > >Maybe. But even mirrors can be burned through by a laser. And then we've >got weight issues that this would entail. It's not like they've got a lot >of overhead for the job. I suspect that faceting wouldn't be any more >effective than a smoothly round body form, it could have aerodynamic >effects as well (ie sharp corners at the facet edges - and yes they could >be rounded - now you're moving back toward a round rocket planform). Ahhh but faceted exterior would deny the adversary less a visual or radar cross section to acquire and track (yeah I know about the tail plume). steve
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Mon, 23 Jul 2001, Steve Schear wrote: > >It's the one they use primarily. > > Only because the rocket exterior has not been "stealthed" via high > reflectivity and faceting. Maybe. But even mirrors can be burned through by a laser. And then we've got weight issues that this would entail. It's not like they've got a lot of overhead for the job. I suspect that faceting wouldn't be any more effective than a smoothly round body form, it could have aerodynamic effects as well (ie sharp corners at the facet edges - and yes they could be rounded - now you're moving back toward a round rocket planform). -- Nature and Nature's laws lay hid in night: God said, "Let Tesla be", and all was light. B.A. Behrend The Armadillo Group ,::;::-. James Choate Austin, Tx /:'/ ``::>/|/ [EMAIL PROTECTED] www.ssz.com.', `/( e\ 512-451-7087 -~~mm-'`-```-mm --'-
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
At 01:28 AM 7/23/2001 -0500, you wrote: >On Sun, 22 Jul 2001, Steve Schear wrote: > > > I wonder what the destructive mechanism is for this system? > >There was an article in IEEE Spectrum last year (I think) on one of the >systems. The main failure mechanism is weakening of the aeroshell and due >to increased loading the missile comes apart. The same sort of thing >happened in Desert Storm with some of the Scuds that used plywood sheeting >instead of aluminum. It's one of the primary factors of their high failure >rate. > > > Heat by radiant absorption seems an obvious but impractical method. > >It's the one they use primarily. Only because the rocket exterior has not been "stealthed" via high reflectivity and faceting. steve
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Mon, 23 Jul 2001, Eugene Leitl wrote: > My comment was limited to radiant energy weapons. Even that's not sufficient since lasers have been demonstrated for mid-course assaults as well. > As to those, the critical vulnerability exists during launch and boost > phase. The target is slow, bright, large, has fuel on board and a > nonarmored hull, which (as other posters observed) can be weakened with > enough flux. All it really takes is to get it cocked a tad off senter and aerodynamic forces will take it apart, irrespective of hull weakness. > The warhead in transit is fast, small, silent, and very, very hard to hit > critically (well, it is designed to withstand reentry and nuclear > antimissile near-hits), especially if it has a high-albedo coating, and if > it is accompanied by a cloud of decoys. Either radiant energy weapon or > kinetic kill, you're on the losing side here. They've certainly managed to kill enough of them in tests starting as far back as the ASAT fighters from the 80's. The reality is that quite a lot of research goes on in attacking the warheads while in the mid-course phase. It's also worth mentioning that in general the individual (assuming MRV) warheads don't usually seperate until after mid-flight. This means a not-so-small target. > > operations, vacuum effects (rupture a fuel tank and watch that baby > > gyrate). > > True, but irrelevant. Actually not, if you strike the tanks (they are typically filled with Nitrogen to both provide strength, ala a plastic coke bottle with the top on and off, and to help move fuel to the engines. Approximately half the flight occurs in this phase. > > Which has been demonstrated to be extant since the mid-80's when they > > shot the first satellite down with a high altitude fighter. > > A missile in boost phase is not a satellite. A cloud of decoys is not a > satellite. An armored warhead is not a satellite. The satellite used was specifically chosen to mimic the characteristics of a re-entry vehicle. All I can say is google and 'anti-satellite aircraft'. -- Nature and Nature's laws lay hid in night: God said, "Let Tesla be", and all was light. B.A. Behrend The Armadillo Group ,::;::-. James Choate Austin, Tx /:'/ ``::>/|/ [EMAIL PROTECTED] www.ssz.com.', `/( e\ 512-451-7087 -~~mm-'`-```-mm --'-
RE: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Mon, 23 Jul 2001, Trei, Peter wrote: > With high-powered lasers, one of the important destructive mechanisms > is blast - the outer layer of the illuminated object vaporizes, and > flies away from the rest of the target. The reactive force of this You're orders of magnitude away from such fluxes. You're trying to hit a moving, rapidly accelerating (possibly flying random evasion maneuvres) high-albedo vehicle -- through the Mach cone, through the 100 km of atmosphere filled with clouds, haze, random fluctuations, etc. Once it's past boost phase, it's essentially invulnerable. Chemical lasers have a limited numbers of shots, every energy leaving the vehicle must pass through it's optics aperture (which must be damn transparent). The vehicle is very complicated and delicate, and expensive. Given that you have to make many kills during few 100 s window, it doesn't appear cost-effective. If it's in LEO, I just launch a bucket of tungsten or depleted uranium birdshot in countersense orbit. Given a few iterations, I can keep surprising amounts of orbital space clean of any operable machinery. > gives the target a hell of a kick. Kicking off strict alignment with > it's flight path, or putting a big dent (or even better a hole) in the If you ablate a bit of hull sufficient to change course, you've killed the vehicle, whether solid boosters, or cryogenic fuel tanks. > side of a missile under several G's of stress traveling at a high Mach > number is not healthy for the missile. > > Laser's have problems though - as they heat the air the refractive > index changes, leading to 'blooming' or beam expansion. At too high a > power density they can also ionize the air, which makes it effectively > opaque. Dust, haze, and clouds are also problems. > > Using *very* short pulses eliminates many of these problems. We're not talking about a fuel pellet in the focus of a NOVA laser.
Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Sun, Jul 22, 2001 at 09:14:56AM -0500, Jim Choate wrote: > Point this baby at the ground... > > http://washingtonpost.com/wp-dyn/articles/A27248-2001Jul20.html That will result only in a very broken 747. -- ___ ___ . . ___ \/ |\ |\ \ _\_ /__ |-\ |-\ \__
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
First post - I hope it goes out Here's a link to the first story I saw about this technology in TechnologyReview. http://www.technologyreview.com/magazine/jul01/freedmanall.asp --- David Honig <[EMAIL PROTECTED]> wrote: > >On Sun, 22 Jul 2001, Steve Schear wrote: > > > >> I wonder what the destructive mechanism is for > this system? > > > >There was an article in IEEE Spectrum last year (I > think) on one of the > >systems. The main failure mechanism is weakening of > the aeroshell and due > >to increased loading the missile comes apart. > > Many missile (propellants) are pressurized; > weakening a bit of the skin > will cause > it to burst. > > > > > > > > > > > > > > > __ Do You Yahoo!? Make international calls for as low as $.04/minute with Yahoo! Messenger http://phonecard.yahoo.com/
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
>On Sun, 22 Jul 2001, Steve Schear wrote: > >> I wonder what the destructive mechanism is for this system? > >There was an article in IEEE Spectrum last year (I think) on one of the >systems. The main failure mechanism is weakening of the aeroshell and due >to increased loading the missile comes apart. Many missile (propellants) are pressurized; weakening a bit of the skin will cause it to burst.
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Mon, 23 Jul 2001, Jim Choate wrote: > Bull. Missiles are vulnerable to various assaults during their entire > flight. The aerodynamic forces during boost and terminal flight My comment was limited to radiant energy weapons. As to those, the critical vulnerability exists during launch and boost phase. The target is slow, bright, large, has fuel on board and a nonarmored hull, which (as other posters observed) can be weakened with enough flux. The warhead in transit is fast, small, silent, and very, very hard to hit critically (well, it is designed to withstand reentry and nuclear antimissile near-hits), especially if it has a high-albedo coating, and if it is accompanied by a cloud of decoys. Either radiant energy weapon or kinetic kill, you're on the losing side here. > operations, vacuum effects (rupture a fuel tank and watch that baby > gyrate). True, but irrelevant. > > You need serious energy flux and tracking precision to terminate a > > warhead. > > Which has been demonstrated to be extant since the mid-80's when they > shot the first satellite down with a high altitude fighter. A missile in boost phase is not a satellite. A cloud of decoys is not a satellite. An armored warhead is not a satellite. The problem assymetry makes star wars a very expensive proposition. Using airborne hardware instead of LEO is a good move, but it falls orders of magnitude short of the target. The demos are just that: demos. Given that a limited strike is best conducted with remotely operated civilian aircraft, or plain old UPS, star wars seems like effect of industrial lobby.
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Mon, 23 Jul 2001, Jim Choate wrote: > Bull. Missiles are vulnerable to various assaults during their entire > flight. The aerodynamic forces during boost and terminal flight My comment was limited to radiant energy weapons. As to those, the critical vulnerability exists during launch and boost phase. The target is slow, bright, large, has fuel on board and a nonarmored hull, which (as other posters observed) can be weakened with enough flux. The warhead in transit is fast, small, silent, and very, very hard to hit critically (well, it is designed to withstand reentry and nuclear antimissile near-hits), especially if it has a high-albedo coating, and if it is accompanied by a cloud of decoys. Either radiant energy weapon or kinetic kill, you're on the losing side here. > operations, vacuum effects (rupture a fuel tank and watch that baby > gyrate). True, but irrelevant. > > You need serious energy flux and tracking precision to terminate a > > warhead. > > Which has been demonstrated to be extant since the mid-80's when they > shot the first satellite down with a high altitude fighter. A missile in boost phase is not a satellite. A cloud of decoys is not a satellite. An armored warhead is not a satellite. The problem assymetry makes star wars a very expensive proposition. Using airborne hardware instead of LEO is a good move, but it falls orders of magnitude short of the target. The demos are just that: demos. Given that a limited strike is best conducted with remotely operated civilian aircraft, or plain old UPS, star wars seems like effect of industrial lobby.
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Mon, 23 Jul 2001, Sampo Syreeni wrote: > Seen some of this before. It's sexy, especially if one thinks of the > propaganda value: it's basically "death from above". You're saying it, "propaganda value". Missiles are only vulnerable during boost phase, while they still have fuel onboard. Chemical lasers are expensive, have limited operation time, are cranky, and laser tracking is a nightmare. Mirroring the surface of the missile is a cheap countermeasure, requiring orders of magnitude larger critical flux and thus driving hardware costs at the other end. You need serious energy flux and tracking precision to terminate a warhead. LEO hardware might be able to do it, but not without much, much, much lower launch costs. -- Eugen* Leitl http://www.lrz.de/~ui22204/";>leitl __ ICBMTO : N48 10'07'' E011 33'53'' http://www.lrz.de/~ui22204 57F9CFD3: ED90 0433 EB74 E4A9 537F CFF5 86E7 629B 57F9 CFD3
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Sun, 22 Jul 2001, Jim Choate wrote: >Point this baby at the ground... > >http://washingtonpost.com/wp-dyn/articles/A27248-2001Jul20.html Seen some of this before. It's sexy, especially if one thinks of the propaganda value: it's basically "death from above". Sampo Syreeni, aka decoy, mailto:[EMAIL PROTECTED], gsm: +358-50-5756111 student/math+cs/helsinki university, http://www.iki.fi/~decoy/front
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
On Sun, 22 Jul 2001, Steve Schear wrote: > I wonder what the destructive mechanism is for this system? There was an article in IEEE Spectrum last year (I think) on one of the systems. The main failure mechanism is weakening of the aeroshell and due to increased loading the missile comes apart. The same sort of thing happened in Desert Storm with some of the Scuds that used plywood sheeting instead of aluminum. It's one of the primary factors of their high failure rate. > Heat by radiant absorption seems an obvious but impractical method. It's the one they use primarily. > If it is, then as the article mentions there may be some inexpensive > and practical countermeasures to such a system, such as making the exterior > of the missile body into a multi-faceted mirror able to reflect both IR and > radar energy (although doing the same for the nose cone might prove more > difficult due to aerodynamics). While reflecting the thermal energy is a good idea, doing the same for radar isn't since it allows more conventional systems to be used to track the missile, contrary to the goal of delivering large quantities time on target. Of course reflecting the IR allows one to use a 'dual component' system whereby another missile homes in on the reflected laser (standard IR designator sort of stuff). Another aspect is to beam the exhaust. By creating hydrodynamic shockwaves in the exhaust cone it should become possible to cause the engine to come apart due to back-pressure or simply creating ancillary thrust vectors and causing the guidance system to mis-calculate. Thrust attack like this must take place very early in the launch or at each stage seperation. You've probably got no more than 30-60 seconds out of a 30 minute flight (for a ICBM that isn't sub launched, then you've got single/double stage and about 15 minutes max). While the current systems won't do it, it should even be possible with high power short pulse width systems to heat the air in front of the rocket to cause turbulence. -- Nature and Nature's laws lay hid in night: God said, "Let Tesla be", and all was light. B.A. Behrend The Armadillo Group ,::;::-. James Choate Austin, Tx /:'/ ``::>/|/ [EMAIL PROTECTED] www.ssz.com.', `/( e\ 512-451-7087 -~~mm-'`-```-mm --'-
Re: Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
At 09:14 AM 7/22/2001 -0500, you wrote: >Point this baby at the ground... > >http://washingtonpost.com/wp-dyn/articles/A27248-2001Jul20.html I wonder what the destructive mechanism is for this system? Heat by radiant absorption seems an obvious but impractical method. If it is, then as the article mentions there may be some inexpensive and practical countermeasures to such a system, such as making the exterior of the missile body into a multi-faceted mirror able to reflect both IR and radar energy (although doing the same for the nose cone might prove more difficult due to aerodynamics). steve
Air Force Turns 747 Into Holster for Giant Laser (washingtonpost.com)
Point this baby at the ground... http://washingtonpost.com/wp-dyn/articles/A27248-2001Jul20.html -- -- Nature and Nature's laws lay hid in night: God said, "Let Tesla be", and all was light. B.A. Behrend The Armadillo Group ,::;::-. James Choate Austin, Tx /:'/ ``::>/|/ [EMAIL PROTECTED] www.ssz.com.', `/( e\ 512-451-7087 -~~mm-'`-```-mm --'-
