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Army Laser Passes Drone-Killing Test
Nerval's Lobster writes "Commercial package-delivery drones such as those revealed by Amazon and DHL could face danger from more than shotgun-toting, UAV-hunting yahoos following the successful test of a drone-killing laser by the U.S. Army. Though it's more likely to take aim at enemy observation drones than Amazon's package-deliver 'copters, the U.S. Army's High Energy Laser Mobile Demonstrator (HEL-MD) did prove itself in tests last week by shooting down 90 incoming mortars and a series of Unmanned Aerial Vehicles (UAV). The original goal during the test at White Sands Missile Range in New Mexico was to burn out or blow up mortar rounds and blind the cameras or other sensors carried by drones. The laser proved capable enough to damage or slice off the tails of target drones, which brought them down, according to Terry Bauer, HEL MD program manager, as quoted in the Dec. 11 Army announcement of the test. The quarter-sized beam of super-focused light set off the explosives in the 60-millimeter mortars in mid-flight, leaving the rest to fall 'like a rock,' Bauer said. The laser could target only one mortar at a time, but could switch targets quickly enough to bring down several mortars fired in a single volley. The laser and its power source are contained in a single 500-horsepower, four-axle truck but was directed by a separate Enhanced Multi Mode Radar system. The next step is a move from New Mexico to a testing range in Florida early next year 'to test it in rain and fog and things like that,' according to Bauer."
Laser, neat. Couldn't you just wrap the UAV in Mylar to deflect it?
Considering drones should be susceptible to conventional means of destruction (read: bullets, missiles), I was wondering why bother with directed energy weapons? The answer appears to be (1) discretion (because a drone dropping out of the sky is totally not attention-grabbing) (2) the ability to shoot through walls (okay, that's pretty cool), and (3) lower "cost per kill."
Using beam splitters, you could in theory target as many targets as the laser can handle while keeping the beams directed. You wouldn't even need to have multiple targeting systems--I vaguely remember seeing a talk once (where the lasers were being used for optical trapping) where the beam pattern was controlled by a single piece of optics.
And using boat rudders, we could in theory target multiple tree-huggers with only one water cannon.
I was wondering why bother with directed energy weapons?
With speed of light weapons the target does not move very far between firing and impact. Point of aim is basically point of impact, unlike bullets. No guidance system required, unlike missiles.
Ammunition is unlimited as long as you have power.
And because sci fi fans have been waiting for this since 1898. The War of the Worlds, H. G. Wells.
This isn't the first U.S. Army laser system that can shoot down mortar rounds. The Tactical High Energy Laser, in test since 2000, could do it. Here it is in action. That took three semitrailers of equipment and tanks for the chemical laser. Each shot cost $3000 in chemicals. Israel wanted to deploy the thing, even though it was expensive to operate, couldn't run for long, and not very portable. It was just too clunky for combat.
The Army wanted a solid-state laser with that kind of punch, and now they have one. This new truck-mounted system uses a 10KW solid-state laser array. Probably a lot of small solid-state lasers. It might just be an array of 1000 standard 10-watt laser diodes. That's enough to take out artillery shells and small rockets. The only consumable is electricity.
Beam weapons are about to become real. The most likely initial user is, again, Israel, which has to deal with small rocket attacks in known areas. Israel's Iron Dome system works reasonably well but uses a pair of $50,000 guided missiles to take out each $800 attacking rocket.