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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.
Number 2: "*ahem* Dr. Evil, it's about the sharks. When you froze them, they were put on the endangered species list. We tried to get some, but it would have taken months to clear up the red tape."
Dr. Evil: "You know, I have one simple request - and that is, to have sharks with frikkin' laser beams attached to their heads! Now evidently my cycloptic collegue informs me that that can't be done. Can you remind me what I pay you people for? Honestly, throw me a bone here. What do we have?
Number 2: "Sea Bass"
Dr. Evil: "Riiiiiight..."
Number 2: "They are mutated sea bass."
Dr. Evil: "Really? Are they ill-tempered?"
Number 2: "Absolutely."
Dr. Evil: "That's a start."
Yes, it looks really ingenious and all, but can I pop popcorn with it from a range of three miles? Hilarity would be bound to ensue!
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)
Heat *is* heat - and when you apply the ammount of heat generated by the ABL System to a Solid fuel, it's going to create quite a big "boom".
Most model rockets today are powered by solid-fuel engines, and if you expose them to heat they'll do wonderfully-interesting things.
ScottKin
I don't give a rat's behind about "karma" here or anywhere else. Don't like what I have to say here? Deal with it!
No, you wake up.
War is bad but there are plenty of things that are worse. Ask any survivor of the concentration camps who was liberated by the Allied Expeditionary Force whether they think war is 'cool.'
Pacifism can be more evil than killing people in some circumstances.
-ccm
Too much Law; not enough Order.
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