March 28, 2013
If there was any doubt that the military has new confidence in its forthcoming laser arsenal, the Navy’s top geeks want to outfit Marines with a laser cannon to shoot small drones out of the sky.
Specifically, the Office of Naval Research thinks that Marine air-ground task forces are too vulnerable to adversaries flying cheap, small spy drones overhead, like thefour-pound Raven the Marines themselves used in Iraq. Its answer: outfit Marine ground vehicles with laser guns.
It’s all part of a new Office of Naval Research program, formally unveiled Thursday, with the clunky name of Ground-Based Air Defense Directed Energy on the Move. For the time being, it’s just a research effort, but the office expects to award grants and contracts for it worth up to $400,000. And it’s doable.
So, the specs. The idea is to get a laser cannon weighing less than 2500 pounds mounted onto a Marine Humvee or comparable truck. The cannon needs to provide a “minimum optical output power” of 25 kilowatts, with an eye toward scaling up to 50 kilowatts, for a two-minute full-power blast. Hardware that can adjust for all “environmental conditions” Marines operate in — from a muggy beach to the arid climes of Helmand Province — is encouraged; the Office is agnostic on how researchers get there.
Is the effort realistic? Yes, but it’s also ambitious.
The Navy is making a big push during 2013 to get its laser arsenal finally out of the lab and into the fleet. The first task anticipated for the laser arsenal is exactly the one envisioned here for Marine trucks — shooting down small drones hovering too close for comfort. The Navy’s had solid-state lasers capable of burning through a boat’s outboard motor at sea for two years, and those models generated 15 kilowatts worth of power. In tests three years ago, an MK-15 Phalanx cannon tricked out to host a laser successfully shot down small drones.
The hard part is going to be generating the power necessary for the laser beam either from a truck or portable within it. The generators on board ships are massive things that can divert enough power to a sub-100 kilowatt laser without jeopardizing propulsion. It’s unclear from the outline the Office of Naval Research provides just how a generator capable of generating 25 kilowatts worth of pew-pew-pew for two minutes and “followed by a 20 minute recharge to 80% of total capacity (power and thermal)” (!) is going to either fit in a Humvee or, more problematically, draw from the truck’s electrical systems. Then there’s the problem of cooling the thing down so it’s safe to drive. (Also, be careful where you point that thing.)
Those are engineering problems that the Office of Naval Research feels confident its industry partners and associated geeks can crack. The effort underscores one of the drawbacks of small surveillance drones, even as they proliferate and generate angst within defense circles: they’re slow and easily shot down — particularly by a line of sight weapon that can burn through them. And the Marines definitely want to demonstrate that as the drones just get cheaper.