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Comment by jMyles | Hacker News Reader

Fuck man. This is the kind of shit that makes me feel guilty about paying taxes.

It is the kind of technology that might prevent drone incursions into crowded stadia.

Countering large numbers of small drones will be a key defensive goal in the future.

Drone could just take a flight path between a passenger airplane and the ground laser pods, such that shooting the laser would fry the airplane behind the drone. It isn't a great solution, when it ever works.

No that's not how lasers and flight paths work. It's impossible to line up aircraft so precisely.

Why? This doesn't make much sense to me.

A small drone won't be able to go fast/far enough.

passenger airplanes not known for going into war zones.

MH17

One stray plane does not a military defense strategy make which was the GP: hide behind commercial aircraft

If you had a battery of lasers, you should be able to cover the sky without hitting unintended targets, because the distance between the drone and plane multiples distance between the ground lasers.

What I’ve come to understand by studying history is that countries without a superior military get subjugated by countries that have one. You can either play the game or lose without putting up a fight.

And yet, raising an army to be defensive just makes your neighbors arm faster to try prevent THEIR demise.

I suspect the details end up having a lot more nuance than one or two sentences can describe.

I mean diplomacy helps too but nobody is going to listen if you don't have a stick to back it up with. See Ukraine for example.

if True we would have 1 global empire.

If you live in the US about 1/3 of your taxes go to making sure we have the means to break things and kill people. It's been that way for a long long time. Whether that is good or bad is a whole different discussion, but throughout history having the biggest stick has proved to be beneficial at least for awhile.

1/3 is a wildly inaccurate number that only comes close to holding true if you don't include our non-obligatory spending which is massive.

Its varied from year to year. I cant keep track what goes to medicaid (and as the baby boomers continue to age it will shift as time moves forward) and want not over the year, Id say the low estimate is 20% of your taxes (and the number are different when you look at mandatory vs discretionary spending) and the high is 36% either way its a lot of money.

11.6% in 2017 https://www.usgovernmentspending.com/breakdown_2017USrt_19rs...

Drop in the bucket of the defense budget... This only amounts to about two new F-18s. At least some basic research might come out of it. There's things my taxes go towards that I feel much more negatively about.

Well, the money is going to R&D so it will advance human knowledge. Are there non-military used for the research? It’s only $150 million. Peanuts. One F35 costs around $100 million.

Didn’t I read somewhere that we spent $20 billion for air conditioning during the war in Afghanistan?

$150m and completion within 1.5 years, seems like zeroes are missing from those numbers

Because this is a development of a production version of an already-existing and -tested prototype.

> Every gun that is made, every warship launched, every rocket fired signifies, in the final sense, a theft from those who hunger and are not fed, those who are cold and not clothed.

150m could do a lot of good. 20B could do even more. Can’t we express a desire for our elected leaders to spend our tax money on good instead of perpetuating the military industrial complex?

Youve got enough comments to reply to so Ill be concise. If this can be used against drone craft or reliably against missiles then I'm for it. If it's just a better gun Im against it.

In all likelihood it's a pretty poor substitute for a gun. Consider that this weapon is suspected to cost around one dollar per shot (not including capital costs, I'm sure.) Figure that the navy generates energy pretty expensively and assume that means ~3kW*hr. Wikipedia says somewhere in the range 15-50kW. (https://en.wikipedia.org/wiki/Laser_Weapon_System).

I'm not up-to-date on the latest and greatest in batteries, but I think a person would have a hard time carrying the energy supply for a laser weapon that is comparable in effectiveness to the many forms of relatively compact guns in their many forms, whether we're discussing anti-air, anti-tank, or anti-personnel.

This is the navy trying to be able to deal with the asymmetry of a battle field in which the most credible threats are swarms of cheap drones. Consider that there are navy ships where the cheapest weapon on-board costs $0.75 million per shot, and it's not surprising that this would be exciting for them.

Just to note: a dollar a shot is not very far off from the current retail price of rifle bullets.

We don't actually point guns up very often though. In part, because the threats move too fast, and in part because bullets come down. What's the ballistic range of 20 mm depleted uranium round? If I shot drones in the Gulf of Aden and end up peppering a mall in Djibouti, we're all going to have a bad day.

The same physics that makes shotguns safe to clay shoot with seem like natural ballistic solutions to this..

But sure, lasers I guess.

The range of a 12 gauge shotgun with a sabot round is claimed to be up to 200 yards. The maximum firing range of a 20 mm cannon is 4 miles. That's without using depleted uranium (which both harder and denser).

Sure, if you can get inside of 40 yards, a shotgun is a great point-defense weapon. You put more muzzle velocity and bigger pellets coming out of it, so you can reach further, well, that gets back to square one.

It's not all that much fun being downrange from somebody shooting at airborne geese from a blind a couple hundred yards off, I can tell you...

Being downrange of a giant laser is probably not fun either. Seems like a good way to blind people by glancing a metal hand rail.

I'm also suspicious of the range of any laser based technology. Atmosphere seems to attenuate it pretty quick. I remember reading in 2007 on slashdot theoretical solutions that shoot some kind of hollow cylinder shaped beam that ionizes the air in the hollow center, allowing a laser to go further before being attenuated.

They must have made some physical advancements far beyond my reading, since birdshot just seems easier.

If you're on a ship with a reactor, it's more just about how you are using your energy than the cost of the energy. You're generating that power no matter what. However if you're on a conventional power then yes you would count it.

I completely disagree. Refueling is incredibly expensive and time consuming, and the frequency of doing so directly results from how carefully fuel is conserved throughout core life.

source?

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