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Comment by anigbrowl | Hacker News Reader

The ever-excellent Congressional Research Service report has all the pew-pew detail that you could possibly ask for: http://fas.org/sgp/crs/weapons/R41526.pdf

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Nice. The article said that the range is classified, but the reports says about it:

""" Department of Defense (DOD) development work on high-energy military lasers, which has been underway for decades, has reached the point where lasers capable of countering certain surface and air targets at ranges of about a mile could be made ready for installation on Navy surface ships over the next few years. More powerful shipboard lasers, which could become ready for installation in subsequent years, could provide Navy surface ships with an ability to counter a wider range of surface and air targets at ranges of up to about 10 miles. """

A mile? 10 miles? Freaking sweet.

This is why the Ford Class aircraft carriers are so ridiculously over provisioned electrically. They have had this stuff in the pipeline for years and had to make sure that this new class of aircraft carriers could handle it when it finally becomes feasible or necessary.

Both this and all the railgun technology the Navy has been developing. Undoubtedly part of the reason the new Zumwalt class destroyers are electric drive.

When I was in Malaysia earlier this year, one of the more popular conspiracy theories about the downing of MH-370 was that it was an accident brought about by testing of these laser weapons by the US Navy. I wonder how likely it is that a missed target would lead to a mistake on that scale, inadvertently, ten miles away?

Even at its full range of 10 miles it would have a tough time hitting a commercial plane. 10 miles is 52,800 feet so the warship would have to be very close to the plane to hit it (almost under it), and within visual range for sure, meaning it wouldn't happen by accident. A ballistic missile on the other hand can travel 1-3,000 miles to hit a target.

It's not like the laser stops dead at 10 miles (or 1 mile). It's just not able to take down a rocket at that range. While I don't think it's very likely that a laser took down the plane, who's to say it wouldn't be able to burn through one layer of wing, and expose/ignite the fuel? I'd imagine the difference between hitting a rounded missile almost head on, and a flat aircraft wing from underneath, is almost like the difference of igniting paper and wood with a laser pointer...

Burning through metal requires the laser to stay focused on the target for a few seconds. That's not going to happen by accident with an airliner moving at hundreds of meters per second and a different velocity than the intended target.

That's the real advantage of the lasers. The beams will essentially travel at the speed of light. At 10 miles, and a C of 186,000 miles per second, that's 10/186000 seconds to go 10 miles. At that distance, refraction and diffusion are probably bigger problems than anything.

I bet you could handle refraction by tracking the target optically, using a camera of the same wavelength as the laser light. The refraction would be the same in both directions.

Neat, Boeing has a 'Directed Energy Systems' division.

It doesn't seem to mention HF. It's a chemical laser. There are ways to recirculate the gas, meaning lesser electrical requirements.

Not sure if even Viton O-rings can deal with it though...

I'm afraid I have no idea what you're talking about. Are you sure you meant to reply to me rather than some other commenter?

I was hoping for technical details on HF lasers. A lot of defence budget money was put in them.

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