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Dawn of the Airborne Laser
Yonzie writes "As you may have heard, there are a number of competing franchises working on a functional laser weapon. Popular Science has an interesting story about `The Wall of Fire', an airborne laser designed to fit in the belly of a 747. Apparently, this is powerful and precise enough to destroy enemy intercontinental and intermediate-range missiles in mid-flight.
I can imagine the use of laser turrets as protection against missiles, but I really can't see the use of a laser mounted in a 747. IMHO, it's way too slow compared to the missiles, and will not be able to scramble fast enough." This is the big daddy of the JSF laser that we've mentioned before.
It is expensive, but during the Cold War we always had some nuclear-armed B-52s flying in the air ready to attack if needed.
The idea is probably to use them to prohibit a retaliatory strike by a country like North Korea after we bomb them.
And this is not just my opinion. For more information on the dangers of these sorts of things, I recommend "Star Wars: A Defense Expert's Case Against the Strategic Defence Initiative" by Robert M Bowman, and his site at http://www.rmbowman.com/ssn/
Also check out his program you can buy at a http://www.alternativeradio.org
Basically, I do agree that if you do the math, these are only useful as weapons designed to follow-up with a pre-emptive attack. These are hence profoundly destabilizing and so they will provide no security for the US.
LedgerSMB: Open source Accounting/ERP
FAS: Airborne Laser
"Lockheed Martin Space Systems, a member of Team Airborne Laser (ABL), has begun fabrication of the revolutionary, high-energy laser weapon system's turret assembly at its Sunnyvale, Calif., facility.
"The turret assembly, located on the nose of the system's modified 747-400 Freighter aircraft, houses a rotating 1.5-meter telescope designed to locate hostile missiles while in their boost phase."
SpaceDaily: LockMart Begins Building Airborne Laser Turret
Taking stuff apart since 1969 (TM)
These lasers are not meant for shooting down surface to air missiles. This laser is designed to kill much larger and (initially) slower targets like ICBMs.
ph34r teh p0w3r 0f th3 c0w
Nukes don't go off from normal explosions -- it takes a lot more energy that a simple explosion to start a fusion reaction.
Most **NUCLEAR** weapons use an **ATOMIC** device to start the reaction of fusing atoms together. So unless blowing up the missle releases enough energy to rival the hiroshima or nagasaki blasts, I think you'd be ok. Of course, there will be some localized radiation, but not a mushroom cloud.
Remember -- there's a big different between nuclear and atomic weapons -- nuclear weapons mimic the sun, by fusing multiple atoms together. Atomic weapons split atoms.
and what about missles with solid rocket motors? I doubt the laser would be any good against these at all.
Clearly, it would have to have a different effect. Solid rocket fuel might be ignitable by the laser, though, so imagine what would happen to a missile that had a hole in its side and hot rocket fuel burning and spewing heat and exhaust out that hole. I suspect a solid rocket would disintegrate quite quickly. And since SRMs generally burn from the inside out, I suspect destroying a missile powered by an SRM would be possible later in the boost phase.
This is meant to fly around a battlefield and shoot down Scuds and similar medium range missiles. It is not meant for strategic defense, because there is presumably no warning on ICBM launches. It is not meant for short range tactical missles, too many of them.
It is a first step, a baby step weapon. You have to take that first step sometime.
Infuriate left and right
1) Clear flyable weather. While you can detect the thermal blooms of launch, you can't rely on that for tracking, thus the need for a ranging laser. Will this work if you've got 5-10k ft of cloud cover to visually confirm the target? How about minor-major turbulance?
The system uses 2 tracking lasers to compensate for up to 500 miles of atmospheric distortion, and since the platform will be flying at 40,000 feet (well above 99.99% of weather systems) and it will only take seconds for an ICBM-class missle to reach that altitute, cloud cover and the minimal amout of turbulance are non-factors.
2) Total aerial supremancy. As with AWACS, you'll need to dominate the skies to the point where SAMs are not making the plane suddenly jink and miss the shot at the wrong time.
SAM's have a limited range, and if anything would be more concerned about strike fighters that are bombing them, not to mention the fact that I'm certian we'll have a sufficent number of EA-6B Prowlers in the air jamming and scrambling the SAM's to avoid long range radar-tracked launches. The ICBM's, in the case of North Korea, would need to rapidly head out over the pacific to reash the US, giving us plenty of controllable airspace to park a 747.
3) Target overload. If there are a "lot" of thermal blooms, how long will it take to determine which one is shooting the real missle? Which is just an fire/explosion on the ground? Recall that Iraq is tasked with destroying 100+ short-range ballistic missles. How do you tell a 200km range missle with a nuke vs. a 50km one with conventional explosives. You have 20 shots to figure it out.
Trajectory tells you all you need to know. A short range weapon will have a much lower track than a long range missle, which will need much higher altitude in order to reach its intended target. A basic knowledge of the opponents ballistic missle capability and a few seconds of tracking data is typically sufficent to provide a fairly accurate track and intended destination for the weapon. Additionally, stationary ground-based heat 'plumes' don't move, and would be easily detected as just that, a ground fire.
4) Equipment. How long to reload between shots? Fast enough to take a second shot? What sort of stress does this put on the plane and the internal equipment? If you do miss, can you still track the missed target?
A good question. Since the reaction that powers the laser is chemical based, it would be interesting to know what the regeneration time is. Stress on the plane should be minimal (there's no real signifigent 'moving parts' to the weapon to induce stress), and it maintains enough reactants for 20 shots.
5) Limited range. From the description it can cover a few hundred square miles. Say 400 square miles or an area of 20 miles by 20 miles. Expand that by constantly flying large fig-8s and you got maybe an area of 3000 sq. miles covered for about five minutes every hour. Lots of luck tracking down the right five minutes of launch...
Generally, if we know an opponent has intercontanental capability, we have a fairly good idea what track a missle would need to take to reach us. In the case of a massive country like the USSR, such a weapon is virtually meaningless, but in a small country like North Korea, it should be simple to cover their launch trajectory.
The system uses a deformable mirror to compensate for phase distortion that occurs naturally in the atomsphere. This was one of the biggest achievments they made back in the early 90's. The whole system has a number of controllable that allow it to adaptively compensate for not only variance but turbulence. See here: http://www.spie.org/web/oer/december/oer_dec95_1.
Also, at 40k feet, this is ABOVE the cloud layer. Once you detect the heat bloom, and there will be a large heat bloom as the missles are essentially standing on pillars of fire, the system begines to prep and waits for the missle to break through the cloud layer, at which point it can target it, measure the return radition from the targeting laser, compensate for distance/atmosphere, and take a shot at it.
This thing is 'parked' in a figure 8 pattern at above 40k feet. SAMs can't reach it. AWACS hangs out at above 29k because of the radar it uses and the value of said radar at 29k. And yeah, duh, you want to keep some sort of enemy fighters away from them. This is a non-issue for the US right now. We have air superiority.
It waits for a missle to break through the cloud layer. If something busts through the cloud layer, at this time it's first come first get shot down. If 100 are launched, and there's only 2 ABL's flying around, yeah, some will get through. But i don't think the people saved from the 20 or so that get shot down are going to complain.
Military secret, but "experts" guesstimate less than a minute.
It's range is again secret but it's assumed to be "100s of kilometers". I'm not going to do the math, but covering say a circular range of 200 miles, at 40k feet gives your a ground coverage of a much larger aspect. Throwing a few of these over North Korea could neuter them on the spot.
-Malakai
-Malakai
A Dragon Lives in my Garage
emember -- there's a big different between nuclear and atomic weapons
Your terminology is faulty.
Both fission and fusion devices are nuclear weapons. In each case, the nucleus of the uranium, plutonium, cesium, or hydrogen fuel is involved in a chain reaction. The fusion reaction is much more energetic, of course.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
The flame from the O-ring burned through the hydrogen tank, but also burned through through the lower SRB mounting strut, which caused the SRB to rotate around the upper strut and puncture the oxygen tank just above the intertank area. At about the same time, the rupture in the hydrogen tank caused the the entire bottom of the external tank to fail, releasing the pressurized contents. This in turn added almost 3 million pounds of thrust to the tank itself, and drove the hydrogen tank upward into the oxygen tank which had already been punctured by the SRB, causing the explosion.
The sequence of events is explained in much more detail in Chapter III of the Rogers Commission report, which can be found here
Please stand clear of the doors, por favor mantenganse alejado de las puertas
Many first generation Japanese Americans from Hiroshima sent their children back for education. As a result at least 3,000 American citizens were killed by the use of their own nuclear weapon.
10% of the victims were Koreans being used in Hiroshima as forced labor. A number of prisoners of war from many countries were also killed by the bomb.
We never hurt only our "enemies."
The ABL / AL-1 is intended to be a "boost phase intercept" (BPI) weapon. It is designed to orbit a potential adversary for several hours at a time with aircraft constantly rotating in and out of theater. With air refueling the AL-1 could stay airborne almost indefinitely only limited by the endurance of the crew. The whole idea is to be able to intercept ballistic missiles while they are still in boost phase shortly after they have been launched causing the debris to fall on the people that launched the missiles in the first place.
BPI is much less risky than terminal phase intercept (i.e. attempting to shoot the missiles down on reentry). If you fail to shoot the target down in boost phase you will at least get a second chance to shoot it down on reentry provided you have missile interceptors in theater (which we do in the case of Iraq).
The AL-1 uses a very powerful chemical Laser which has a range of several hundred miles (between 200-800 miles) and if I recall correctly has enough chemical fuel for about 26 shots. The laser itself occupies virtually the entire length of the airframe with the fuel storage tanks being in the aft section to the best of my recollection.
Hopefully we will have a few AL-1s available in theater for the impending war with Iraq.
Even if we only have a couple of prototypes that is still better than nothing.
Despite the fact that we have numerous missile interceptors in the form of the MIM-104 PAC2 Patriot all over the world we do not have the ability to intercept ballistic missiles worldwide with a high degree of success. The AL-1 would vastly increase our ability to perform a successful intercept. We could probably keep the continental US safe with about 10 AL-1s rotating in and out. Naturally it would be nice to have a backup in the form on NMD (National Missile Defense) with other systems supplementing our defenses. Ideally, if we could park a small constellation of satellites with HELs (High Energy Lasers) in orbit around the planet we could provide global coverage against ALL ballistic missiles (short range, intermediate range and intercontinental) launched from anywhere on earth thus ensuring global peace and stability.
Live long and prosper
Unix_Geek_65535