Warships May Get Lasers For Close-In Defense 482
King Louie writes "Raytheon and the US Navy have successfully tested a ship-borne laser capable of shooting down aircraft. Video at the link shows the 32-kilowatt solid-state laser shooting down an unmanned aerial vehicle. The technology is apparently mature enough to be deployed as part of ships' short-range missile defenses, a role currently filled by the Basic Point Defense Missile System (based on the Sea Sparrow missile) and the Close-In Weapons System (based on a 20mm Gatling gun)."
Re:Paint the Target (Score:3, Interesting)
If you can keep a laser beam on target that long, you might as well use the laser to guide an effective, high explosive round to it.
Sounds like faulty reasoning to me. For one thing, there are many values for "a long time." If you have to hold the guidance laser on the target for 30 seconds, but the defense laser for 20 seconds, those are both non-instantaneous, but when you're talking about an enemy aircraft trying to bomb you, I'd assume that's a world of difference. Also seems like we might not want missiles certain situations, like maybe when the enemy aircraft are in close proximity to friendly aircraft. I'd also expect the effective distance would be different Maybe the lasers have a wider effective range, closer, farther, or both? Are the sea sparrows they're replacing laser guided?
Lastly, I don't know much about laser guidance systems, but couldn't there be countermeasures for laser guidance that wouldn't be possible for a laser boring through the plane? Seems like a plane shining a laser off of itself might be able to redirect the missile, wheras the plane would need to be coated in a very good mirror to deflect the laser?
Navy's answer to Chinese Anti-Carrier Missile (Score:2, Interesting)
Chinese have developed and are testing the Dong Feng 21D missile, capable of accurately targeting and hitting a moving navy Aircraft Carrier from 2000 miles away. US experts are scared. Since capabilities of this missile are not fully known to US Navy, their strategy to combat it currently is SM-3 interceptor rockets launched from Aegis destroyers and cruisers that escort Aircraft Carriers.
Problem with that is that the reloading capacity of these Aegis equipped ships isn't fast enough to protect against a volley of Dong Feng 21Ds. So they are pretty much screwed. Currently Aircraft Carriers are the most effective way of projecting current US air superiority anywhere in the world. Imagine the implications of a bunch of US carriers being sunk.
This laser defense system may be Navy's answer to this new missile threat.
Re:Fricken ships! (Score:5, Interesting)
Laser beams AND rail guns. The USN is on the verge of becoming a very "SciFi" weapons platform. If everything takes twice as long as planned then by 2020 you're going to see USN ships equipped with both weapons systems. Rail Guns firing projectiles at OTH targets at 5600MPH and handling close in threats with Phalanx CIWS upgraded with LASERS.
This IS the future.
Re:Paint the Target (Score:3, Interesting)
Seems like they had to hold the laser on the target for a long time until it worked.
I wonder what happens when your target is rotating, thus not exposing the same spot to the heat... oh dear, did I just counter a multi-million dollar weapon system?
I'm sure it works fine on drones that fly in a straight line and are painted black.
Re:Other options... (Score:4, Interesting)
So..."if the heatshield is ablative, then after an exceedingly short period of time, the superheated air is now hitting the real surface and doing damage, no?" Or perhaps the idea behind ablative surfaces is exactly to dissipate far larger amounts of energy than it would be otherwise possible without them...it's not about absolute defense (it never is), just about changing the odds
Gases don't "burn of" - at most they can turn to plasma; which would be a great thing - it's not translucent.
And hey, if the baloons are released from some distance / are just floating there... ;p
Re:Navy's answer to Chinese Anti-Carrier Missile (Score:4, Interesting)
A carrier group would be the least of our worries if the Chinese decided to launch a surprise attack. It would have to be a surprise attack, because we wouldn't put our ships within range of them unless we had some plan or some way of negating the threat. Telling a few soldiers to rush a machine gun nest is one thing, but telling a large part of our navy to rush the equivalent of a machine gun nest is quite another. Carrier groups are NOT expendable unless that's our only option.
The scenario could go two ways.
The Chinese launch a surprise attack and there's an 80% casualty rate within a carrier group. We send a few hundred cruise missiles to rain down on their capital and shore line defenses while another carrier group comes to fill in the position. One side backs off when the other starts threatening to launch nukes.
Or, the Chinese declare war on us for some reason and aside from a few slap fights and invasion of Taiwan/Japan/Korea, we don't see much action because we're currently tied up in the cat box of the Middle East. We damn sure don't send a carrier group into hell's maw to die to those missiles.
Re:Yeah. (Score:3, Interesting)
Why can't the pulse compression technology that's used for lasic lasers be used for military lasers?
If the problem is painting the same spot on a missile for a second or so, wouldn't it be a lot easier if a 0.1 second pulse is compressed down to a femtosecond so all the energy put into the laser over the course of 0.1 seconds is delivered in 0.000000000000001 seconds?
Re:32 kilowatt!!! (Score:3, Interesting)
That would, of course, cause power to be diverted from all other systems, but who among us wouldn't love the idea of being present in the control room and having the lights dim as the ship fires it's ultimate weapon.
Re:Priorities (Score:3, Interesting)
Why don't you sell the computer and donate the money to charity?
Because that, like your question, would be incredibly stupid, shortsighted, and entirely besides the point.
If America is broke, we should be rolling back the tax cuts for the wealthy and withdrawing our troops from around the world, or at least preparing our allies for the eventuality. But we're not broke - people are just hoodwinking the populace into accepting that without any evidence, and using the resulting hysteria for their own purposes.
Tracking and ballistic calculations (Score:5, Interesting)
Bullets and lasers deliver this energy differently
Completely true but there are other factors to consider, the most important of which is actually hitting the target. The most important advantage lasers have is target tracking. With bullets you have to consider two trajectories (the bullet and the target) neither of which is likely to be perfectly straight. With lasers you simply aim directly at the target which is a much simpler tracking problem to solve, especially with modern sensors and vision systems. No need to consider the effects of wind, gravity, aerodynamics, bullet speed, etc. This doesn't make it a trivial problem to solve but it does have advantages.
I think the speed of targeting will be especially interesting and important against hypersonic cruise missiles. I'm curious how long it would take to destroy a missile approaching at 2000 m/s (mach 6). From the time the missile appears on the horizon a close in defense system would have 3-8 seconds to destroy a missile traveling at those speeds depending on how high it was mounted.
Not to say that bullets/shells don't have advantages too. Tricks like proximity fuses obviously aren't possible with lasers.
Of course, the Phalanx shoots 50-75 rounds a second , for a total muzzle energy/second of firing of a whopping 2269kJ.
Only relevant if all the bullets all hit, which they pretty much never do.
Re:Priorities (Score:3, Interesting)
something the various armed forces of the world are actively prepared to do again.
The actions we guard against are exactly the actions we execute every single day across the world. We're not scared of Russia or China or Cuba trying to invade the homeland. We're scared of someone we're abusing fighting back.
Re:Navy's answer to Chinese Anti-Carrier Missile (Score:1, Interesting)
USSR was brought down by spending more than they could borrow. If China wants to bring the US down, all it needs to do is stop lending money.
Re:Fricken ships! (Score:3, Interesting)
But completely useless against low tech diver and C4.
I love sci fi weapons as much as the next geek but seriously. I wouldn't say "This IS the future" as it's a well known fact that navies are always gearing up to fight the last war (and I'm not singling out the USN, how much did the US, British, Nazi German and Japanese navy spend on battleships in the 30's only to have them rendered obsolete by cheaper carriers and land based aircraft, all navies are really guilty of thinking in the past).
Stealth ships and UAV's are the immediate future, by 2020 most navies will field stealth destroyers or frigates (Singapore and the Finns already are). I'm not making any bets on 2040.
Re:32 kilowatt!!! (Score:2, Interesting)
Re:Yeah. (Score:2, Interesting)
Have a look at actual military spending figures world wide. If anyone is going to be using any swarming tactics, it's the US, not Korea or China. Land war, of course China is going to have more boots on the ground - but not more drones/missiles etc. at their current spending levels.
http://www.globalissues.org/article/75/world-military-spending [globalissues.org]
You ever wonder why the US is having economic problems? Here's a hint: Have a look at what happened to the USSR. Perhaps if less money was actually spend on weapons and technology to blow shit up, and more was spend on capital infrastructure that is actually useful for production, the US wouldn't be in as big an economic the hole it is these days.
Re:Priorities (Score:3, Interesting)
I live in a reality based on historical fact, not on wish-thinking and jingoism. So I imagine that's quite disconnected from your reality.
Here's an argument for your belief system [project-syndicate.org] that is reasonably rounded, but wrong. Here's why:
To be sure, the US now has more power resources relative to other countries than Britain had at its imperial peak. But the US has less power - in the sense of control over other countries' internal behavior - than Britain did when it ruled a quarter of the globe.
For example, British officials controlled Kenya's schools, taxes, laws and elections - not to mention its external relations. America has no such control today. In 2003, the US could not even get Mexico and Chile to vote to support a second resolution on Iraq in the UN Security Council...
In fact, the problem of creating an American empire might better be termed imperial underreach . Neither the US public nor Congress has proven willing to invest seriously in the instruments of nation building and governance as opposed to military force.
At the time this was written by the former Assistant Secretary of Defense, the United States was the de facto ruler of Iraq and Afghanistan, which it had invaded only a few years earlier. It had supported, and nearly pulled off a coup in Venezuela in 2002. In the aftermath of 9/11, it was using secret military agents to kidnap terrorism suspects, dropping them off for torture at secret prisons around the world, and while declaring "war" on terrorism, it used some pathetic legalistic wringing of hands to ignore even it's own standards of detainee treatment in the US Army Field manual.
Even turning to the two examples he provided - Mexico and Chile - is even more illustrative of his ignorance, feigned or not.
Possession of small amounts of drugs including heroin, cocaine and marijuana is now decriminalized in Mexico... A similar decriminalization bill passed Mexico’s Congress in 2006 but the Fox administration decided not to sign it, reportedly because of opposition in the United States.
http://www.drugpolicy.org/news/pressroom/pressrelease/pr082109a.cfm [drugpolicy.org]
"I don't see why we need to stand by and watch a country go communist due to the irresponsibility of its own people. The issues are much too important for the Chilean voters to be left to decide for themselves." — Henry Kissinger
http://en.wikipedia.org/wiki/CIA_activities_in_Chile [wikipedia.org]
Re:32 kilowatt!!! (Score:1, Interesting)
This is a CW (Continuous Wave) laser. It creates heat for as long as it paints the target. It's actually a massive array of diode fiber lasers that are spliced together to sum their power, which is why it's so efficient compared to chemical lasers. Most likely it's an array of 3200 10w IR lasers.
Phalanx does not impact every round with the target--typically the target (a missile) explodes the first time a round impacts it. Like all machine guns, it compensates for a lack of accuracy (caused by the relatively low speed of the round and aerodynamics) with large number statistics. The core problem is that Phalanx has a 700 round magazine, which takes less than 20 seconds of continuous fire to burn through. The laser has no magazine limit, and unlike stationary lasers, it probably has no heat dissipation limit since it can be water cooled with water cycled from the ocean.