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Navy Planning To Build Laser Cannon In Four Years
CowboyRobot writes "The US Navy is months away from requesting bids from contractors to construct a laser weapon for its ships, now that the technology is feasible. 'The key point came last April, when the Navy put a test laser firing a (relatively weak) 15-kilowatt beam aboard a decommissioned destroyer... the Martime Laser Demonstrator cut through choppy California waters, an overcast sky and salty sea air to burn through the outboard engine of a moving motorboat a mile away.'"
High power lasers will smoke a typical mirror. There are reflective surfaces that could work, but you have to keep them perfectly clean. Not happening at sea for long... However, a laser will be easier to track back than a tracer round...
So Navy's of tomorrow will have their ships covered in mirrors. Now, someone tell me why this won't work... because it seems like a really obvious way to divert a laser beam.
Because a mirror does not reflect 100% of the energy, some will be absorbed, thus the laser will eventually burn through it. Super efficient mirrors are easy counter anyway, just lob some "buckshot" at the target to shatter the mirrors, then burn the ship up with the laser :-)
If the attacking boat has a corner cube reflector there is a good chance of blinding people on the defending ship. Since the system needs to be ready for use without warning, the crew would need to always wear laser goggles.
You can protect a missile with an ablative shield - the sort used for re-entry vehicles. This doesn't need to be high tech - wood works surprisingly well (used by the Chinese for spacecraft years ago).
You could use a more diffuse beam to blind the crew of an attacking boat, but I think that violates the Geneva convention.
I'm also very skeptical about the 1MW -> 20' of steel / second. At a kilometer away, you probably have a spot size of around a centimeter. (it depends on wavelength, optics, etc, but that is the right ball park. Iron vaporization energy is 300KJ/mole or about 6KJ/gm. A 1cm long by 10M piece of iron is 1000 cc's or ~10^4 grams. So that's 60MJ to vaporize, or a minute, not a second to burn through. Of course the plume of iron vapor will disrupt the incoming beam so it will take a lot longer. This also assumes you can keep the beam perfectly focused.
The is also the question of whether a complex device like an FEL can be kept always ready to fire within a second. The light is much faster, but its not clear that when you include the time to ready and aim the weapon that the time to hit the target is faster than for a high speed gun.
The Navy wants this so that, when they're dealing with a small boat that's causing a problem, they have an option between "ignore" and "blow them out of the water". Somalia pirates, smugglers, boats getting too close (see USS Cole) - things like that.
High power lasers will smoke a typical mirror. There are reflective surfaces that could work, but you have to keep them perfectly clean. Not happening at sea for long... However, a laser will be easier to track back than a tracer round...
Maybe, maybe not.
If the laser light doesn't scatter much, the only one who can track it back to its source is the target.
But only AFTER getting blasted.
Of course, you could look out for the fricken' shark in the first place... ;-)
If this stays as a (relatively) short range weapon, which is likely given the way lasers work in the atmosphere, then I doubt that being able to trace the beam back to its source will matter much. A modern US destroyer is over 500 ft long. Based on the one mile range listed in the summary, it would be clearly visible, even to the naked eye.
Yup - the trick is just to design the laser so that the light slows down enough to get into a stable orbit... then you can just fire the laser and it will follow the contour of the earth. Things like mountains and hills can be overcome by firing it even more slowly in a ballistic trajectory.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
I strongly suspect that this laser is intended as a replacement for existing point-defense systems(Phalanx). For longer ranges the navy also has a railgun scheme going, along with existing missiles and aircraft.
It isn't entirely clear that the lasers will work(the demo with the lower powered unit burning an outboard motor took a pitifully long time and that was just a normal outboard motor. No attempt at optical countermeasures, no ablative coatings, no tricks at all); but it should be possible to keep photons on target where it wouldn't be possible for an autocannon to deliver bullets. Also, the navy is in the position where they are pretty much forced to operate on the assumption that something must work and lasers are among the more plausible contenders...
Basically, we have the world's largest investment in aircraft carriers, and stuff for them to carry, and they've been the navy's force-projecting pride and joy since approximately the point in WWII where it became clear that battleships were overpriced floating coffins against even fairly paltry aircraft. Now, if anti-ship missiles and the like cannot be intercepted by some sort of point defense system, it is the aircraft carrier's turn to go the way of the battleship. That would be 10s of billions of dollars worth of awkward(best case, HQ submits to the inevitable in time, the carriers are reduced to a mixture of rotting at the docks and punching defenseless little countries. Worst case, HQ doesn't submit to the inevitable, some scruffy band of militants with a budget so small that an American defense contractor wouldn't bother to steal it sinks something expensive and most of its crew).
“Subsonic cruise missiles, aircraft, fast-moving boats, unmanned aerial vehicles” — Mike Deitchman, who oversees future weapons development for the Office of Naval Research, promises Danger Room that the Navy laser cannons just over the horizon will target them all. I'm confused. Surely the one thing a laser canon can't do is target things from over the horizon.
I think he is using the word horizon as a metaphor for "coming soon" not a target on the literal horizon. Sloppy wording for sure, it took me a moment to process as well.
I wish I was a neutron bomb, for once I could go off...
That would be a devastating defense.
I'm sure the Navy will remember it next time they're up against a borg cube.
Wouldn't the obvious solution be to create ships which absorb incoming energy and re-use it for their own use?
If I extend that "obvious solution" to apply to how to counter, say, nuclear weapons, you'll see why that won't work.
Do you mean "your remaining eye"?
If this stays as a (relatively) short range weapon, which is likely given the way lasers work in the atmosphere, then I doubt that being able to trace the beam back to its source will matter much. A modern US destroyer is over 500 ft long. Based on the one mile range listed in the summary, it would be clearly visible, even to the naked eye.
Further, something big enough to take out an outboard motor, even scaled up, is at best, a point defense weapon (cruise missiles, very small surface craft, close in helicopters, etc.) Even something 10 times as powerful does not completely disable a frigate sized surface vessel before it can return fire with missiles, guns, and torpedo.
However, looking at the video, the time it takes to burn thru a thin-skinned outboard motor, on a boat that was barely moving, and making no effort to avoid the engagement, suggests that there is a long way to go before this could be a missile defense.
So the use case shrinks even further.
Most anti-ship missiles tend to cluster around a speed of 1000 km/h, which means they cover that last km in .27 seconds. And some US missiles arrive at over 4000 km/h.
Unless a massively scaled up version can track an incoming missile traveling that fast, and engage it, burn it, or blind it in that .27 seconds, its use as fleet CIWS seems limited at best. The only saving grace is the last km is usually (but not always) a head on straight in attack, making tracking easier.
Sig Battery depleted. Reverting to safe mode.
Some military equipment has long been covered in ablative paint. Laser strikes, creates cloud of of particles which diffuse the beam preventing further damage. The identification of materials with suitable oxides or nitrides is left as an exercise for the reader.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Surface forces have no defense against missile attacks, making them useless in a real war
Ah, not exactly true.
http://en.wikipedia.org/wiki/Close-in_weapon_system
http://www.raytheon.com/capabilities/products/searam/
http://en.wikipedia.org/wiki/RIM-116_Rolling_Airframe_Missile
Sig Battery depleted. Reverting to safe mode.