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goddamnedfrank3/07/2015 6:10:16 pm PST
BETHESDA, Md., March 3, 2015 - Lockheed Martin’s [NYSE: LMT] 30-kilowatt fiber laser weapon system successfully disabled the engine of a small truck during a recent field test, demonstrating the rapidly evolving precision capability to protect military forces and critical infrastructure.

Known as ATHENA, for Advanced Test High Energy Asset, the ground-based prototype system burned through the engine manifold in a matter of seconds from more than a mile away. The truck was mounted on a test platform with its engine and drive train running to simulate an operationally-relevant test scenario.

I’m curious how they deal with the waste heat. I don’t know exactly what efficiency they’re getting out of the system but afaik the sweet spot on the input output curve for typical semi conductor lasers is around 25% efficiency. That means this system is producing 90 Kilojoules of waste energy during every second of operation. An air asset has limited options for dealing with waste heat, some of it can be dumped into the thermal mass of the fuel, but that’s an obviously diminishing resource.

This device, as powerful as it is, is also still at least three and a half times weaker than what most experts consider to be the minimum threshold for a practical, fieldable direct energy weapon. They don’t say how many “seconds” it took to burn through the engine block, but maintaining that kind of beam control from a moving platform onto another moving platform won’t be a trivial task.

I can see why the Navy is interested in going down this road for point defense for those warships that can meet the power requirements, because ballast tanks offer enormous and continuously refreshable heat dump. However the hurdles for airborne applications are still enormous. So shooting through the top of a static, tipped up truck seems like a premature and overly optimistic demonstration of the concept. It’s going to be a long, long time I think before we see stuff like this firing down from the air.

But whatever, still cool.