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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."
Hmm, I believe these are the kinds of missions where they make sure n number of planes are always in the air. Sounds really expensive in terms of fuel, but I've heard of several occasions where they do this kind of thing...
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)
I saw a presentation when I was in grad school on the previous incarnation of the 747-laser. The big problem was the laser could only blow up the missle if its tanks were mostly full of fuel.
This is because missle fuel tanks are under high pressure so that the fuel can help form part of the structure for the missle to support the weight of the fuel. If a laser can weaken the walls of the fuel tank then the missle's structure will fail, and the missle will break up.
Anyway these lasers have to hit a missle right after it launches or else the tanks have lost too much pressure and the laser won't do any damage... the presenter defended this by saying you want to shoot down a missle close to launch anyway because you don't want the debris from the missle falling on any friendlies... and this is a good argument (the scuds shot down by patriots in gulf war I caused a lot of damage when they fell out of the sky).
I do have to wonder, though, if the missle launches can be detected and the missle targeted quickly enough for these lasers to work... and what about missles with solid rocket motors? I doubt the laser would be any good against these at all.
There are 10 types of people in this world, those who can count in binary and those who can't.
I think we should call the first 747 with a mounted laser off the line "TROGDOR THE BURNINATOR!"
It will fly above the clouds. No fog or rain at 40,000 feet. It will also target missiles that have cleared the cloudbank, while they are still on ascent.
Guess what...war begets war. Weapons beget weapons.
Uh, no. War begats peace. Overwhelming weapons begats non-proliferation.
Why do you think the world has as much peace as it has? It's the called the US Military. The bigger the imbalance of power between the US and the rest of the world, the less the rogue nations will be tempted to invade their neighbors. Unfortunately, expansionism is alive and well in the middle east.
Someday all the countries of the world will be stable democracies, but that day is not today.
Sometimes it's best to just let stupid people be stupid.
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
War begats peace. [...] Freedom is slavery. Ignorance is strength.
I should just ignore something this absurd, but... it's kind of frightening that someone moderated it up.
The word "is" in this context means equivalence. "Freedom is equivalent to slavery" is a contradiction, as is "ignorance is equivalent to strength".
You'll note that nowhere did I claim that "war is equivalent to peace", and in fact, the whole concept has nothing to do with the subject at hand.
The word "beget" means "leads to". Too many people have no concept of what "peace" really means. Stop and think about it for a second... WAY too many people think that "being in favor of peace" is some noble position to take. It never occurs to them that EVERYONE IS IN FAVOR OF PEACE. DUH!
It takes no courage to advocate peace, because there is no one who doesn't advocate peace. Everyone's goal is peace; the only question is how to achieve peace.
You cannot achieve peace by appeasing military dictators with expansionist goals. It's worth pointing out that the same debates took place in the 1930s during Hitler's rise. Imagine if the world had had the guts to stand up to Hitler at the time. Everyone knew he was dangerous, but everyone wanted "peace at any cost". And that lead to millions upon millions of deaths.
The peaceniks seem to think that if we just disbanded the US military then suddenly the world would join hands and weep with joy at world peace suddenly attained.
Sometimes it's best to just let stupid people be stupid.