By: over G
- 26th June 2005 at 17:03Permalink- Edited 1st January 1970 at 01:00
over-g IF what you reckon is true and that the thing is useless over such a distance at such a height it limits its operational usefullness to tactical/theatre wide applications.......now, can they point it DOWN????
man, is obvious that im talking about ballistic miss¡les, the shoot wont be vertical, it will be mostly horizontal (if it want range), then the air density is more constant and the laser (X ray) wont have a big range, now it it point down the problem increase, because the air density is higher.
the laser isnt usefullness but it have limits
Yeah, downwards over a barbecue!! Will do those burgers and suasages to a right old crisp!!!!!!
yeah, i will see mr. bush cooking a barbacue in the white house with the 747 laser only to intimidate ingnorants guests (as part of the war against terror)
By: sferrin
- 26th June 2005 at 18:30Permalink- Edited 1st January 1970 at 01:00
man, is obvious that im talking about ballistic miss¡les, the shoot wont be vertical, it will be mostly horizontal (if it want range), then the air density is more constant and the laser (X ray) wont have a big range, now it it point down the problem increase, because the air density is higher.
the laser isnt usefullness but it have limits
yeah, i will see mr. bush cooking a barbacue in the white house with the 747 laser only to intimidate ingnorants guests (as part of the war against terror)
By: over G
- 26th June 2005 at 18:58Permalink- Edited 1st January 1970 at 01:00
The ABL isn't an X-ray laser.
well, is very high frecuency, i dont know if is X or high UV, but is iodine-oxigen, that say all, the russians are the masters of iodine-O lasers, but they use that only in ISKRA experiments (nuclear fusion)
New
Posts: 424
By: pluto77189
- 27th June 2005 at 13:08Permalink- Edited 1st January 1970 at 01:00
Isn't it an IR laser?
I'm excited about the ASAT capability of the thing. It can fly pretty high, and it's supposed to have a range of 200 miles horizontally. The air only get thinner, so I imagine targets above the AL will be vulnerable beyond the normal horizontal range. They tend to be shielded from radiation, but I bet the optics and sensors will get fried pretty quick.
By: Iranian F-14A
- 28th June 2005 at 03:48Permalink- Edited 1st January 1970 at 01:00
again the innocent optimism...
well, i think that is a interesting idea, but we must see the reality, at 15000mts there is enough air density to absorb high frecuency energy ( well thats the reason why we can fly without X-ray protection at such heighs), if i remember well there were two options or an IR laser (efficient, but to emmit a decent power output it needs a huge "glass") or a X ray (iodine-oxigen), the 747 use this last, so we must see what is the true range, also the laser must point the target few seconds (few seconds to that precision margin its an eternity), the time of energy "reload" and how many shoots can do -remember that the fuel of the plane is compromised by the energy-hunger laser and the tactical range-, the machine will work, but will be also limited.
Im not a ballistic ICBM missiles expert, but i think that the MIRVs are deployed at hundreds of km from the target (i dont know if are thousands).
and knowing how the russians think, well i wouldnt be surprised if they deploy inner reflectant coatings for their missiles, at the long way is only light (and is reflected, actually in that way the laser works), and the cilindrical surface is pretty perfect to that
anyone have a pic of the soviet Il76 80s airborne laser???
I have a good pic of the Russian Beriev A-60,but it was too large to post.Theres also a nice profile at the Wings Palette site at WP.SCN.RU,and look under Modern Transports,IL-76,Russia.The pics I got were from the Beriev Company site which I found by googling "Beriev A-60".Very nice color pics of this rare aircraft.I know for awhile the site was taken down,but as far as I know,its back up again.Very Interesting aircraft.
By: over G
- 28th June 2005 at 05:11Permalink- Edited 1st January 1970 at 01:00
Isn't it an IR laser?
I'm excited about the ASAT capability of the thing. It can fly pretty high, and it's supposed to have a range of 200 miles horizontally. The air only get thinner, so I imagine targets above the AL will be vulnerable beyond the normal horizontal range. They tend to be shielded from radiation, but I bet the optics and sensors will get fried pretty quick.
thats a interesting opinion, and i share that, the ABL will be a better ASAT than ABM, but in practical terms i prefer an small ABM with a good fighter plataform, now how the sistem perform against high orbit satelites???, well those machines are specially very well shielded,so we must see...
and no the ABL isnt a IR laser, but maybe it use a transmutator to change the frecuency of the photon, but losing energy (but i dont think that the engieneers were sooooo stupid to design an iodine-O laser to emmit IR frecuecy)
one thing that i still dont understand is the position of the "glass", i mean , the best position isnt above the wings-fuselage???, why they putted there???......maybe for downward shoots???.....maybe against cruiser missiles (but the energy disipacion should be huge) or to induce cancer on "terrorists" :p
By: BuffPuff
- 28th June 2005 at 15:04Permalink- Edited 1st January 1970 at 01:00
Here's a thought. If I had a batch of Scuds, SS-20's etc and wanted as many to potentetially get past an ABL, could I not just apply a shiny mirrored surface to my missiles to scatter the laser energy??
By: sferrin
- 28th June 2005 at 16:54Permalink- Edited 1st January 1970 at 01:00
thats a interesting opinion, and i share that, the ABL will be a better ASAT than ABM, but in practical terms i prefer an small ABM with a good fighter plataform, now how the sistem perform against high orbit satelites???, well those machines are specially very well shielded,so we must see...
"a small ABM with a good fighter platform"? What are you trying to say?
and no the ABL isnt a IR laser, but maybe it use a transmutator to change the frecuency of the photon, but losing energy (but i dont think that the engieneers were sooooo stupid to design an iodine-O laser to emmit IR frecuecy)
It's probably a tradeoff of a sorts. The longer wavelengths travel through the atmosphere better.
one thing that i still dont understand is the position of the "glass", i mean , the best position isnt above the wings-fuselage???, why they putted there???......maybe for downward shoots???.....maybe against cruiser missiles (but the energy disipacion should be huge) or to induce cancer on "terrorists" :p
It's probably for a couple reasons. Field of fire and less turbulance.
By: over G
- 28th June 2005 at 17:12Permalink- Edited 1st January 1970 at 01:00
"a small ABM with a good fighter platform"? What are you trying to say?
yes,yes,yes, i mean a ASAT missile
It's probably a tradeoff of a sorts. The longer wavelengths travel through the atmosphere better.
no, man, if in the end they use the IR frecuency, and see that at such frec the laser works better, man, that mean that the design was a failure (just like the NOVA experiments in which the scientifics designed a IR laser complex, but later they start to use transmuters to UV-X frecuency, pretty failure)
It's probably for a couple reasons. Field of fire and less turbulance.
well, for ballistic missiles a better position is above the fuselage,you have a better coverage area and less plataforms to secure the zone, but maybe they found some problems with the 747 "hump", the turbulence effects on a laser performance isnt big and i dont think that the factor would be critical for the plataform (but if the laser is shoot backwards ,the plane turbulence will be an important factor, and maybe the hump is also a turbul-issue), i think that the laser position is a mistake, because the plane must the in the direction of the enemy position to have a good interception probability, not in a convetional patrol circuit, that mean that the 747 must move to "catch" the missile and must be closer to the enemy lines, so if you want youre scuds to pass, you only need the 747 position
about the laser countermeasures (reflectant surfaces), that could work, covering the mirrow layer with a special paint that could be vaporized with the frecuency-energy laser, and expose the reflecting paint or tiles (whatever) to the laser, could work very good
By: Vortex
- 29th June 2005 at 02:04Permalink- Edited 1st January 1970 at 01:00
a simple google...
Applications of the Chemical Oxygen-Iodine Laser
Chemical oxygen-iodine lasers have demonstrated a wide range of applications from industrial materials processing tasks of high-speed cutting, drilling, and rock crushing to the possible destruction of tactical ballistic missiles.
AFRL's Directed Energy Directorate, Laser Division, Cooperative Development Branch, Kirtland AFB NM
In 1977, the Directed Energy Directorate invented the chemical oxygen-iodine laser (COIL). The initial laser achieved a total power of only 0.01 watts. Since 1977, several COIL devices have evolved. The current COIL test bed is the research assessment device improvement chemical laser (RADICL). RADICL, created in 1995, is a 20 kilowatts (kW) class supersonic COIL that utilizes a rotating disk oxygen generator coupled to a Mach-2 single split supersonic nozzle. It demonstrated a greatly improved chemical efficiency, provided advanced diagnostics, and furthered illuminator research. COIL is a high-power laser useful for applications that require the delivery of a substantial amount of energy to a very small focused laser spot. It is a member of the class of high-power lasers (including the neodymium doped yttrium aluminum garnet (Nd:YAG) and carbon dioxide (CO2) lasers) that are also useful for government and industrial applications. These include materials processing tasks of high-speed cutting and drilling, rock crushing, and nuclear warhead/power plant dismantlement. COIL technology has received considerable interest over the last several years due to its short, fiber-deliverable wavelength (1.315 µ), scalability to very high powers, and nearly diffraction-limited optical quality.
The COIL lasing process starts with an aqueous mixture of hydrogen peroxide and potassium hydroxide called basic hydrogen peroxide, the key constituent of which is hydroperoxy ion. This liquid then reacts with gaseous chlorine to produce heat, salt (potassium chloride), and oxygen in an electronically-excited state called oxygen singlet delta. Because the singlet oxygen has an extremely long spontaneous lifetime (approximately 45 minutes), it can be used as an energy source if a mechanism exists to transfer the energy to a lasing species. Atomic iodine is nearly resonant with singlet delta oxygen, which allows energy to transfer rapidly to it upon collision with the oxygen. To obtain atomic iodine, molecular iodine is injected into the gas flow upstream from the laser cavity where it mixes and entrains in the flow. Collisions with some of the singlet delta oxygen lead the iodine to an excited vibrational state that later dissociates upon further collisions with singlet delta molecules. The atomic iodine is energized to form an optical gain region and power is extracted with an optical resonator at the COIL wavelength of 1.315 µ. The exhaust gases are then passed through standard halogen scrubbers to remove any remnant chlorine and iodine.
The following characteristics make the COIL a very promising candidate for high-power industrial applications. First, it is a near-infrared laser with a wavelength of 1.315 µ. This provides very good coupling of laser energy with metals for high-speed material processing and is one of the best wavelengths for transmission through fused silica optical fibers. Second, because COIL is a low-pressure flowing gas laser, the thermal distortion of the gain medium is extremely small, making it possible to extract a high optical quality beam that can be focused to small spots for faster metal cutting. The demonstrated optical quality for COIL is nearly diffraction limited. Third, the directorate demonstrated COIL to be scalable for powers up to 40 kW and readily scaled to any power necessary to meet very high-power industrial laser needs. COIL is the only laser that has no issues in prohibiting scaling to very high powers. Fourth, the chemicals used in a COIL are all commonly found in heavy industry, with well-known and safe-handling techniques. Finally, the by-products of the COIL lasing operation are salt, water and oxygen; no greenhouse effect gases exist.
Currently, the Nd:YAG and CO2 lasers are the most widely used industrial lasers for high-speed metal cutting and other materials processing tasks. COIL, however, offers distinct advantages over each of these lasers because of the potential of scaling to high-power levels (tens of kW, continuous wave), coupled with the ability to deliver power via fiber optics.
The directorate demonstrated rapid cutting of hastelloy and stainless steel using fiber optics. The RADICL device was operated with a stable resonator to produce a circular COIL beam with very few transverse modes. As shown in Figure 1, the resonator was configured with a z-pass setup to produce improved beam quality. This configuration produced a beam with approximately 33 transverse modes. The out-coupler had a low wedge angle to reduce far field alignment error. The optical setup produced a focal spot diameter calculated to be 0.24 mm. The lenses and beam splitters were fused silica to reduce the amount of heating and maintain good ratios of thermal capacity to the linear expansion coefficient. Beam train calculations were determined with Gaussian propagation equations. Geometric ray tracing was performed to determine optimal lens design for small spherical aberration. Alignment was accomplished with a 1.3 µ semi-conductor laser. The alignment method was specially designed to ensure the alignment beam was co-aligned with the RADICL beam. This method used a quad cell, where the quad cell sensor was located exactly at the 1.3 µ geometric focus of a Newport KPX211 lens. Table 1 lists the descriptions and specifications for all optics used in the beam train, along with the mirror spacing information. Power was measured departing the device and exiting the fiber optic via disk calorimeters. Power coupled into the fiber was calculated from beam train losses between the first disc calorimeter and the fiber.
Once the alignment into the fiber optic was established, the same resonator and beam train configuration was used for the metal cutting experiments. Simple cutting and drilling experiments were performed. A Haas Laser Technologies, Inc. end effector (see Figure 1) was attached to the end of the fiber optic and supplied with 30 psi of gaseous nitrogen to prevent back-spatter on the fiber. Hastelloy-C metal plates were positioned in front of the end effector and moved across the beam using a translational stage. After measuring power delivered into the fiber optic, several cuts through 9.5 mm thick steel were demonstrated. Again, the average power coupled into the fiber for the 10-second runs was around 3.5 kW. Peak power levels of up to 7.36 kW were recorded for the first few seconds of irradiation. No damage was observed to the low-loss fibers.
The directorate continues research into transitioning COIL to an operational system. Materials processing tasks include laser cutting, drilling, and welding, as well as laser marking. The directorate has also undertaken several validation experiments to demonstrate the utility of COIL for potential industrial applications (see Figure 2). One of these experiments established a world record for laser power transmission through a 900µ optical fiber at 7.36 kW. Under a Cooperative Research and Development Agreement (CRADA), the Colorado School of Mines demonstrated rock crushing with the COIL for oil-drilling applications. Remote delivery of the beam has the advantage of removing the laser from the processing floor, thus addressing safety concerns associated with chemical laser operation while increasing the flexibility for cutting table layout to optimize production efficiency. This also allows for remote operations using robotic manipulators for material processing in hazardous environments or confined spaces. As reported by Vetrovec et al.1, this remote capability is especially crucial for applications of laser power to decommission and dismantle aging nuclear facilities, where the task is complicated by limited access into highly contaminated areas. Finally, the USAF Airborne Laser program, which is currently in development, uses a COIL as a defense against enemy missiles.
These experiments demonstrate the utility of the COIL to deliver high power through fiber optics for use in industrial metal cutting. The low-loss fiber optic used in these cutting experiments was standard off-the-shelf technology and no damage was incurred. With the power limitations of Nd:YAG lasers and the inability of CO2 lasers to effectively couple into fiber optics, the COIL remains the only laser capable of delivering tens of kilowatts via fibers. This capability makes the COIL extremely marketable as an industrial laser for use in environments requiring higher power levels and remote power delivery, such as nuclear reactor demolition and decommissioning.
Contributing authors in this research include Dr. Kip R. Kendrick and Capt Brian Quillen, both of the Directed Energy Directorate.
Figure 1. Beam train configuration for fiber optic coupling, with Haas Laser Technologies, Inc. end effector
Figure 2. COIL material processing tasks and experimental results
Table 1. Specifications and descriptions for beam train optics used in fiber coupling experiments and mirror separations
Dr. William P. Latham of the Air Force Research Laboratory's Directed Energy Directorate wrote this article. For more information, access the Technical Support Package (TSP) free on-line at http://www.afrlhorizons.com, contact TECH CONNECT at (800) 203-6451 or visit the web site at http://www.afrl.af.mil/techconn/index.htm.
Reference document DE-99-02.
References
1 Vetrovec, J. Hindy, R. N. Subbaraman, G. and Spiegel, L. "High-Power Iodine Laser Application for Remote D&D Cutting." Proceeding of the SPIE - The International Society for Optical Engineering, vol 3092 (1997), 780-783.
By: over G
- 29th June 2005 at 05:17Permalink- Edited 1st January 1970 at 01:00
hmmmm...yes i went wrong, i just confused COIL (chemical, oxygen-iodine) with the other iodine lasers (like in the PERUN-ISKRA complex), maybe the problem was to relationate the airborne lasers with the thermonuclear lasers (ISKRA-NOVA-SHIVA-OMEGA,something which i love to study),if im wrong, i accept that, no problem man
btw the COIL has other problem....its laser is induced by a no reverseble chemical reaction, nice to charge constanty the Cl2, h2o2, i2 gases.....
such frecuency have not use, we are going from extreme to extreme, to output a decent energy from frequencies arround IR you need a much bigger glass, i really thought the X ray beam, because the mirrow is too small for an IR beam, also IR frequency reflects better on bodies -now imagine if they put mirrows on scuds-, that stuff will hit...........like a girl..
the COIL advantages to fiber optic are obvious, at such low frecuency has a lot of refraction (no reflection)
New
Posts: 362
By: cru
- 29th June 2005 at 10:29Permalink- Edited 1st January 1970 at 01:00
The Airborne Laser (ABL) is the U.S. Air Force's radical new approach for disabling or destroying threat ballistic missiles immediately after launch, during their vulnerable boost phase of launch. Onboard a Boeing 747, the ABL will use the Infrared Surveillance Subsystem (IRSS) to detect and precisely locate threat missiles for engagement by the ABL's megawatt class laser. IRSS leverages some of the latest Infrared Search and Track (IRST) and Active Ranging Sensor (ARS) technologies to perform the real-time detection and precise target tracking functions.
The ABL team is comprised of Boeing, responsible for building the 747 aircraft and the BMC4I computer; TRW, responsible for building the laser; and Lockheed Martin, responsible for Beam Control/Fire Control and the IRSS. Employing six IRSTs, IRSS is capable of rapidly searching a large airspace volume, generating precise two-dimensional tracks on threat missiles during both their boost and post-boost phases of flight. The IRST system can generate detections at very long ranges, then handing off to a CO2 laser ARS for track refinement and precise range measurement. The ABL project is currently in the Program Definition and Risk Reduction (PDRR) phase. Live fire testing of the entire ABL system is scheduled for 2003.
New
Posts: 424
By: pluto77189
- 29th June 2005 at 14:12Permalink- Edited 1st January 1970 at 01:00
The placement of the turret gives it the greatest possible rang eof
movement. It protrudes a bit, so it can be fired back a few degrees, as
well as anywhere ahead of th eaircraft. If placed on top, targets slightly
below the aircraft would be hard to hit, plus, the wings , tail and vertical
stabilizer would be in the way.
There is zero probability of the beam being obstructed by any part of the
aircraft.
It is clearly areodynamically superior in the nose of the aircraft, rather
than a bump that distrubs the airflow over the body.
It allows the optics to be more straightforward. the components of the
laser are straight, and do not need to be directed 90degrees, maximizing
beam effeciency.
And they can shoot downwards as well...if they want to.
The ABL would probably only work for low orbit spy sattelites. Things
in geosynch are tens of thousands of miles up, and not likely to be
unshielded from radiation. Still, several seconds of laser radiation might
be enough to damage sensors and transmitters, or photo cells.
New
Posts: 2,228
By: coanda
- 29th June 2005 at 14:17Permalink- Edited 1st January 1970 at 01:00
Flight has reported that the turret creates a boundary layer around the nose of somthing of the order of 80 INCHES not only will all the air data sensors found there be useless, it'll do nothing for speed, range, endurance and fuel consumption, a top mounted turret would have actually been MORE aerodynamically efficient.
By: over G
- 29th June 2005 at 15:52Permalink- Edited 1st January 1970 at 01:00
a top mounted laser is more practical for ABM sistems, you can do shoots easier on patroll trayectories ,thats very important because you dont need to move the 747 -that affect the accuracy- and dont forget that the jumbo isnt the most maneuverable machine in the world...., but i think that the 747 hump was a problem (for the laser coverage and turbulence over the laser), also they tried to design something more versatile, and use the shoot-down capacity maybe against cruiser missiles or.........afgan villagers.......
New
Posts: 2,228
By: coanda
- 29th June 2005 at 15:55Permalink- Edited 1st January 1970 at 01:00
i dont deny that over-g, but my point still stands, its an aerodynamically unefficient solution.......oh, and why not have two turrets, one above and one below as in the b29, your only shooting at one target at a time, and as technology improves you could employ both at the same time.
By: Bager1968
- 9th July 2005 at 08:01Permalink- Edited 1st January 1970 at 01:00
The point that almost everyone seems to be missing with the "mirror defense" theories is that the Laser will not melt its way through the missile body, nor will it heat it to weaken it. In the early tests with the ALL, they found that the target Sidewinders were actually damaged by a physical shockwave!
When they recovered the pieces and re-assembled them, they found a series of cracks running radially from a central point (where the paint was scorched), much like what you get by hitting a sheet of glass with a hammer.
Metallurgical analysis found that the cracks showed the characteristics of an impact fracture, not a thermally caused one. If you had high-school physics, you learned that light photons have a measureable mass, although it is very small! The energy involved in the super-high power lasers is so great that the light actually has a kinetic energy (mass X velocity) similar to a decent sized bullet. the shock-wave caused by the impact of the light on the missile body breaks the casing.
Mirrors were tested and found not to reduce this impact force significantly.
By: sferrin
- 9th July 2005 at 08:37Permalink- Edited 1st January 1970 at 01:00
The point that almost everyone seems to be missing with the "mirror defense" theories is that the Laser will not melt its way through the missile body, nor will it heat it to weaken it. In the early tests with the ALL, they found that the target Sidewinders were actually damaged by a physical shockwave!
When they recovered the pieces and re-assembled them, they found a series of cracks running radially from a central point (where the paint was scorched), much like what you get by hitting a sheet of glass with a hammer.
Metallurgical analysis found that the cracks showed the characteristics of an impact fracture, not a thermally caused one. If you had high-school physics, you learned that light photons have a measureable mass, although it is very small! The energy involved in the super-high power lasers is so great that the light actually has a kinetic energy (mass X velocity) similar to a decent sized bullet. the shock-wave caused by the impact of the light on the missile body breaks the casing.
Mirrors were tested and found not to reduce this impact force significantly.
That sounds a little fishy. If it was producing the kinetic impact you suggest that also means it would have measureable recoil. I've never heard anything remotely claiming this. And yes, it does BURN it's way through. If you've ever seen any of the videos from the test on the Titan 1 body segment the surface layers of the missile (paint, oxides, dirt, or whatever) burst into flame for roughly a second and a half before the thing failed catestrophically. And go download some of the videos from the THEL tests against mortar rounds and rockets. The beam definitely dwells on the target for several seconds before the target fails.
By: Vortex
- 9th July 2005 at 09:45Permalink- Edited 1st January 1970 at 01:00
actually, the problem with the mirror defense is that a mirror isn't as much an ideal "mirror". No, mirrors won't work. The reason some people bring it up is because of their experiences (or thought experiences) with low power lasers. The question one should ask is what exactly is a mirror...what's the physical construct of a "mirror". As to UVs...now, there's this thing called the Ozone :rolleyes: Besides, that would mean even the IRST needs to be of a similar wavelength. Not practical at all. As to the turret structure/position, its a combination of a lot of compromises, but i wouldn't be surprised at the fact that a 747 has a upper flight deck. Think about it...structurally it just simplifies all the equipment spaces significantly.
Posts: 1,838
By: over G - 26th June 2005 at 17:03 Permalink - Edited 1st January 1970 at 01:00
man, is obvious that im talking about ballistic miss¡les, the shoot wont be vertical, it will be mostly horizontal (if it want range), then the air density is more constant and the laser (X ray) wont have a big range, now it it point down the problem increase, because the air density is higher.
the laser isnt usefullness but it have limits
yeah, i will see mr. bush cooking a barbacue in the white house with the 747 laser only to intimidate ingnorants guests (as part of the war against terror)
Posts: 9,683
By: sferrin - 26th June 2005 at 18:30 Permalink - Edited 1st January 1970 at 01:00
The ABL isn't an X-ray laser.
Posts: 1,838
By: over G - 26th June 2005 at 18:58 Permalink - Edited 1st January 1970 at 01:00
well, is very high frecuency, i dont know if is X or high UV, but is iodine-oxigen, that say all, the russians are the masters of iodine-O lasers, but they use that only in ISKRA experiments (nuclear fusion)
Posts: 424
By: pluto77189 - 27th June 2005 at 13:08 Permalink - Edited 1st January 1970 at 01:00
Isn't it an IR laser?
I'm excited about the ASAT capability of the thing. It can fly pretty high, and it's supposed to have a range of 200 miles horizontally. The air only get thinner, so I imagine targets above the AL will be vulnerable beyond the normal horizontal range. They tend to be shielded from radiation, but I bet the optics and sensors will get fried pretty quick.
Posts: 451
By: Iranian F-14A - 28th June 2005 at 03:48 Permalink - Edited 1st January 1970 at 01:00
I have a good pic of the Russian Beriev A-60,but it was too large to post.Theres also a nice profile at the Wings Palette site at WP.SCN.RU,and look under Modern Transports,IL-76,Russia.The pics I got were from the Beriev Company site which I found by googling "Beriev A-60".Very nice color pics of this rare aircraft.I know for awhile the site was taken down,but as far as I know,its back up again.Very Interesting aircraft.
Posts: 1,838
By: over G - 28th June 2005 at 05:11 Permalink - Edited 1st January 1970 at 01:00
thats a interesting opinion, and i share that, the ABL will be a better ASAT than ABM, but in practical terms i prefer an small ABM with a good fighter plataform, now how the sistem perform against high orbit satelites???, well those machines are specially very well shielded,so we must see...
and no the ABL isnt a IR laser, but maybe it use a transmutator to change the frecuency of the photon, but losing energy (but i dont think that the engieneers were sooooo stupid to design an iodine-O laser to emmit IR frecuecy)
one thing that i still dont understand is the position of the "glass", i mean , the best position isnt above the wings-fuselage???, why they putted there???......maybe for downward shoots???.....maybe against cruiser missiles (but the energy disipacion should be huge) or to induce cancer on "terrorists" :p
Posts: 545
By: BuffPuff - 28th June 2005 at 15:04 Permalink - Edited 1st January 1970 at 01:00
Here's a thought. If I had a batch of Scuds, SS-20's etc and wanted as many to potentetially get past an ABL, could I not just apply a shiny mirrored surface to my missiles to scatter the laser energy??
Thoughts please....
Posts: 9,683
By: sferrin - 28th June 2005 at 16:54 Permalink - Edited 1st January 1970 at 01:00
"a small ABM with a good fighter platform"? What are you trying to say?
It's probably a tradeoff of a sorts. The longer wavelengths travel through the atmosphere better.
It's probably for a couple reasons. Field of fire and less turbulance.
Posts: 1,838
By: over G - 28th June 2005 at 17:12 Permalink - Edited 1st January 1970 at 01:00
yes,yes,yes, i mean a ASAT missile
no, man, if in the end they use the IR frecuency, and see that at such frec the laser works better, man, that mean that the design was a failure (just like the NOVA experiments in which the scientifics designed a IR laser complex, but later they start to use transmuters to UV-X frecuency, pretty failure)
well, for ballistic missiles a better position is above the fuselage,you have a better coverage area and less plataforms to secure the zone, but maybe they found some problems with the 747 "hump", the turbulence effects on a laser performance isnt big and i dont think that the factor would be critical for the plataform (but if the laser is shoot backwards ,the plane turbulence will be an important factor, and maybe the hump is also a turbul-issue), i think that the laser position is a mistake, because the plane must the in the direction of the enemy position to have a good interception probability, not in a convetional patrol circuit, that mean that the 747 must move to "catch" the missile and must be closer to the enemy lines, so if you want youre scuds to pass, you only need the 747 position
about the laser countermeasures (reflectant surfaces), that could work, covering the mirrow layer with a special paint that could be vaporized with the frecuency-energy laser, and expose the reflecting paint or tiles (whatever) to the laser, could work very good
Posts: 3,131
By: Vortex - 29th June 2005 at 02:04 Permalink - Edited 1st January 1970 at 01:00
a simple google...
Applications of the Chemical Oxygen-Iodine Laser
Chemical oxygen-iodine lasers have demonstrated a wide range of applications from industrial materials processing tasks of high-speed cutting, drilling, and rock crushing to the possible destruction of tactical ballistic missiles.
AFRL's Directed Energy Directorate, Laser Division, Cooperative Development Branch, Kirtland AFB NM
In 1977, the Directed Energy Directorate invented the chemical oxygen-iodine laser (COIL). The initial laser achieved a total power of only 0.01 watts. Since 1977, several COIL devices have evolved. The current COIL test bed is the research assessment device improvement chemical laser (RADICL). RADICL, created in 1995, is a 20 kilowatts (kW) class supersonic COIL that utilizes a rotating disk oxygen generator coupled to a Mach-2 single split supersonic nozzle. It demonstrated a greatly improved chemical efficiency, provided advanced diagnostics, and furthered illuminator research. COIL is a high-power laser useful for applications that require the delivery of a substantial amount of energy to a very small focused laser spot. It is a member of the class of high-power lasers (including the neodymium doped yttrium aluminum garnet (Nd:YAG) and carbon dioxide (CO2) lasers) that are also useful for government and industrial applications. These include materials processing tasks of high-speed cutting and drilling, rock crushing, and nuclear warhead/power plant dismantlement. COIL technology has received considerable interest over the last several years due to its short, fiber-deliverable wavelength (1.315 µ), scalability to very high powers, and nearly diffraction-limited optical quality.
The COIL lasing process starts with an aqueous mixture of hydrogen peroxide and potassium hydroxide called basic hydrogen peroxide, the key constituent of which is hydroperoxy ion. This liquid then reacts with gaseous chlorine to produce heat, salt (potassium chloride), and oxygen in an electronically-excited state called oxygen singlet delta. Because the singlet oxygen has an extremely long spontaneous lifetime (approximately 45 minutes), it can be used as an energy source if a mechanism exists to transfer the energy to a lasing species. Atomic iodine is nearly resonant with singlet delta oxygen, which allows energy to transfer rapidly to it upon collision with the oxygen. To obtain atomic iodine, molecular iodine is injected into the gas flow upstream from the laser cavity where it mixes and entrains in the flow. Collisions with some of the singlet delta oxygen lead the iodine to an excited vibrational state that later dissociates upon further collisions with singlet delta molecules. The atomic iodine is energized to form an optical gain region and power is extracted with an optical resonator at the COIL wavelength of 1.315 µ. The exhaust gases are then passed through standard halogen scrubbers to remove any remnant chlorine and iodine.
The following characteristics make the COIL a very promising candidate for high-power industrial applications. First, it is a near-infrared laser with a wavelength of 1.315 µ. This provides very good coupling of laser energy with metals for high-speed material processing and is one of the best wavelengths for transmission through fused silica optical fibers. Second, because COIL is a low-pressure flowing gas laser, the thermal distortion of the gain medium is extremely small, making it possible to extract a high optical quality beam that can be focused to small spots for faster metal cutting. The demonstrated optical quality for COIL is nearly diffraction limited. Third, the directorate demonstrated COIL to be scalable for powers up to 40 kW and readily scaled to any power necessary to meet very high-power industrial laser needs. COIL is the only laser that has no issues in prohibiting scaling to very high powers. Fourth, the chemicals used in a COIL are all commonly found in heavy industry, with well-known and safe-handling techniques. Finally, the by-products of the COIL lasing operation are salt, water and oxygen; no greenhouse effect gases exist.
Currently, the Nd:YAG and CO2 lasers are the most widely used industrial lasers for high-speed metal cutting and other materials processing tasks. COIL, however, offers distinct advantages over each of these lasers because of the potential of scaling to high-power levels (tens of kW, continuous wave), coupled with the ability to deliver power via fiber optics.
The directorate demonstrated rapid cutting of hastelloy and stainless steel using fiber optics. The RADICL device was operated with a stable resonator to produce a circular COIL beam with very few transverse modes. As shown in Figure 1, the resonator was configured with a z-pass setup to produce improved beam quality. This configuration produced a beam with approximately 33 transverse modes. The out-coupler had a low wedge angle to reduce far field alignment error. The optical setup produced a focal spot diameter calculated to be 0.24 mm. The lenses and beam splitters were fused silica to reduce the amount of heating and maintain good ratios of thermal capacity to the linear expansion coefficient. Beam train calculations were determined with Gaussian propagation equations. Geometric ray tracing was performed to determine optimal lens design for small spherical aberration. Alignment was accomplished with a 1.3 µ semi-conductor laser. The alignment method was specially designed to ensure the alignment beam was co-aligned with the RADICL beam. This method used a quad cell, where the quad cell sensor was located exactly at the 1.3 µ geometric focus of a Newport KPX211 lens. Table 1 lists the descriptions and specifications for all optics used in the beam train, along with the mirror spacing information. Power was measured departing the device and exiting the fiber optic via disk calorimeters. Power coupled into the fiber was calculated from beam train losses between the first disc calorimeter and the fiber.
Once the alignment into the fiber optic was established, the same resonator and beam train configuration was used for the metal cutting experiments. Simple cutting and drilling experiments were performed. A Haas Laser Technologies, Inc. end effector (see Figure 1) was attached to the end of the fiber optic and supplied with 30 psi of gaseous nitrogen to prevent back-spatter on the fiber. Hastelloy-C metal plates were positioned in front of the end effector and moved across the beam using a translational stage. After measuring power delivered into the fiber optic, several cuts through 9.5 mm thick steel were demonstrated. Again, the average power coupled into the fiber for the 10-second runs was around 3.5 kW. Peak power levels of up to 7.36 kW were recorded for the first few seconds of irradiation. No damage was observed to the low-loss fibers.
The directorate continues research into transitioning COIL to an operational system. Materials processing tasks include laser cutting, drilling, and welding, as well as laser marking. The directorate has also undertaken several validation experiments to demonstrate the utility of COIL for potential industrial applications (see Figure 2). One of these experiments established a world record for laser power transmission through a 900µ optical fiber at 7.36 kW. Under a Cooperative Research and Development Agreement (CRADA), the Colorado School of Mines demonstrated rock crushing with the COIL for oil-drilling applications. Remote delivery of the beam has the advantage of removing the laser from the processing floor, thus addressing safety concerns associated with chemical laser operation while increasing the flexibility for cutting table layout to optimize production efficiency. This also allows for remote operations using robotic manipulators for material processing in hazardous environments or confined spaces. As reported by Vetrovec et al.1, this remote capability is especially crucial for applications of laser power to decommission and dismantle aging nuclear facilities, where the task is complicated by limited access into highly contaminated areas. Finally, the USAF Airborne Laser program, which is currently in development, uses a COIL as a defense against enemy missiles.
These experiments demonstrate the utility of the COIL to deliver high power through fiber optics for use in industrial metal cutting. The low-loss fiber optic used in these cutting experiments was standard off-the-shelf technology and no damage was incurred. With the power limitations of Nd:YAG lasers and the inability of CO2 lasers to effectively couple into fiber optics, the COIL remains the only laser capable of delivering tens of kilowatts via fibers. This capability makes the COIL extremely marketable as an industrial laser for use in environments requiring higher power levels and remote power delivery, such as nuclear reactor demolition and decommissioning.
Contributing authors in this research include Dr. Kip R. Kendrick and Capt Brian Quillen, both of the Directed Energy Directorate.
Figure 1. Beam train configuration for fiber optic coupling, with Haas Laser Technologies, Inc. end effector
Figure 2. COIL material processing tasks and experimental results
Table 1. Specifications and descriptions for beam train optics used in fiber coupling experiments and mirror separations
Dr. William P. Latham of the Air Force Research Laboratory's Directed Energy Directorate wrote this article. For more information, access the Technical Support Package (TSP) free on-line at http://www.afrlhorizons.com, contact TECH CONNECT at (800) 203-6451 or visit the web site at http://www.afrl.af.mil/techconn/index.htm.
Reference document DE-99-02.
References
1 Vetrovec, J. Hindy, R. N. Subbaraman, G. and Spiegel, L. "High-Power Iodine Laser Application for Remote D&D Cutting." Proceeding of the SPIE - The International Society for Optical Engineering, vol 3092 (1997), 780-783.
Posts: 1,838
By: over G - 29th June 2005 at 05:17 Permalink - Edited 1st January 1970 at 01:00
hmmmm...yes i went wrong, i just confused COIL (chemical, oxygen-iodine) with the other iodine lasers (like in the PERUN-ISKRA complex), maybe the problem was to relationate the airborne lasers with the thermonuclear lasers (ISKRA-NOVA-SHIVA-OMEGA,something which i love to study),if im wrong, i accept that, no problem man
btw the COIL has other problem....its laser is induced by a no reverseble chemical reaction, nice to charge constanty the Cl2, h2o2, i2 gases.....
such frecuency have not use, we are going from extreme to extreme, to output a decent energy from frequencies arround IR you need a much bigger glass, i really thought the X ray beam, because the mirrow is too small for an IR beam, also IR frequency reflects better on bodies -now imagine if they put mirrows on scuds-, that stuff will hit...........like a girl..
the COIL advantages to fiber optic are obvious, at such low frecuency has a lot of refraction (no reflection)
Posts: 362
By: cru - 29th June 2005 at 10:29 Permalink - Edited 1st January 1970 at 01:00
About pointing accuracy: the aiming is done by a set of 6 IRSTs (AAL 42) wich is the F14D's IRST; the range is measured by a CO2 laser mounted in a lantirn pod.This is from Lockheed Martin missiles & fire control site (http://www.lockheedmartin.com/wms/findPage.do?dsp=fec&ci=11272&rsbci=13640&fti=124&ti=0&sc=400):
Posts: 424
By: pluto77189 - 29th June 2005 at 14:12 Permalink - Edited 1st January 1970 at 01:00
The placement of the turret gives it the greatest possible rang eof
movement. It protrudes a bit, so it can be fired back a few degrees, as
well as anywhere ahead of th eaircraft. If placed on top, targets slightly
below the aircraft would be hard to hit, plus, the wings , tail and vertical
stabilizer would be in the way.
There is zero probability of the beam being obstructed by any part of the
aircraft.
It is clearly areodynamically superior in the nose of the aircraft, rather
than a bump that distrubs the airflow over the body.
It allows the optics to be more straightforward. the components of the
laser are straight, and do not need to be directed 90degrees, maximizing
beam effeciency.
And they can shoot downwards as well...if they want to.
The ABL would probably only work for low orbit spy sattelites. Things
in geosynch are tens of thousands of miles up, and not likely to be
unshielded from radiation. Still, several seconds of laser radiation might
be enough to damage sensors and transmitters, or photo cells.
Posts: 2,228
By: coanda - 29th June 2005 at 14:17 Permalink - Edited 1st January 1970 at 01:00
Flight has reported that the turret creates a boundary layer around the nose of somthing of the order of 80 INCHES not only will all the air data sensors found there be useless, it'll do nothing for speed, range, endurance and fuel consumption, a top mounted turret would have actually been MORE aerodynamically efficient.
Posts: 1,838
By: over G - 29th June 2005 at 15:52 Permalink - Edited 1st January 1970 at 01:00
a top mounted laser is more practical for ABM sistems, you can do shoots easier on patroll trayectories ,thats very important because you dont need to move the 747 -that affect the accuracy- and dont forget that the jumbo isnt the most maneuverable machine in the world...., but i think that the 747 hump was a problem (for the laser coverage and turbulence over the laser), also they tried to design something more versatile, and use the shoot-down capacity maybe against cruiser missiles or.........afgan villagers.......
Posts: 2,228
By: coanda - 29th June 2005 at 15:55 Permalink - Edited 1st January 1970 at 01:00
i dont deny that over-g, but my point still stands, its an aerodynamically unefficient solution.......oh, and why not have two turrets, one above and one below as in the b29, your only shooting at one target at a time, and as technology improves you could employ both at the same time.
Posts: 1,838
By: over G - 29th June 2005 at 16:10 Permalink - Edited 1st January 1970 at 01:00
with such monster, who cares about aerodynamic (yes is important, but not critical), yes you could be right, but who cares?...
about the 2 turrets, well it adds weight, and weight is a critical factor in any plane, specially with such heavy hardware
Posts: 3,614
By: Bager1968 - 9th July 2005 at 08:01 Permalink - Edited 1st January 1970 at 01:00
The point that almost everyone seems to be missing with the "mirror defense" theories is that the Laser will not melt its way through the missile body, nor will it heat it to weaken it. In the early tests with the ALL, they found that the target Sidewinders were actually damaged by a physical shockwave!
When they recovered the pieces and re-assembled them, they found a series of cracks running radially from a central point (where the paint was scorched), much like what you get by hitting a sheet of glass with a hammer.
Metallurgical analysis found that the cracks showed the characteristics of an impact fracture, not a thermally caused one. If you had high-school physics, you learned that light photons have a measureable mass, although it is very small! The energy involved in the super-high power lasers is so great that the light actually has a kinetic energy (mass X velocity) similar to a decent sized bullet. the shock-wave caused by the impact of the light on the missile body breaks the casing.
Mirrors were tested and found not to reduce this impact force significantly.
Posts: 9,683
By: sferrin - 9th July 2005 at 08:37 Permalink - Edited 1st January 1970 at 01:00
That sounds a little fishy. If it was producing the kinetic impact you suggest that also means it would have measureable recoil. I've never heard anything remotely claiming this. And yes, it does BURN it's way through. If you've ever seen any of the videos from the test on the Titan 1 body segment the surface layers of the missile (paint, oxides, dirt, or whatever) burst into flame for roughly a second and a half before the thing failed catestrophically. And go download some of the videos from the THEL tests against mortar rounds and rockets. The beam definitely dwells on the target for several seconds before the target fails.
Posts: 3,131
By: Vortex - 9th July 2005 at 09:45 Permalink - Edited 1st January 1970 at 01:00
actually, the problem with the mirror defense is that a mirror isn't as much an ideal "mirror". No, mirrors won't work. The reason some people bring it up is because of their experiences (or thought experiences) with low power lasers. The question one should ask is what exactly is a mirror...what's the physical construct of a "mirror". As to UVs...now, there's this thing called the Ozone :rolleyes: Besides, that would mean even the IRST needs to be of a similar wavelength. Not practical at all. As to the turret structure/position, its a combination of a lot of compromises, but i wouldn't be surprised at the fact that a 747 has a upper flight deck. Think about it...structurally it just simplifies all the equipment spaces significantly.