Comment by Bender | Hacker News Reader

Comment by Bender | Hacker News Reader

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Israel, United States, United Kingdom, China and Russia have HEL high-energy lasers that can shoot down fast drones. Several other countries are working on HEL development. The numbers of operational HEL systems are still very small but growing. I believe that Israel have the most of them in operation today developed primarily by Rafael Advanced Defense Systems. 10kw to 50kw on trucks, 100kw ground based. Range: 7-10km, shorter in fog or rain. Dwell time: 4 to 5 seconds. Cost per shot: $2–$3.50.

Targets: UAVs/drones (including swarms), short-range rockets (Qassam-style), mortars, artillery shells, cruise missiles, and potentially other low/slow-flying threats. It excels against cheap, high-volume threats where kinetic interceptors are uneconomical.

The US is working on a megawatt version that will be mounted on ships to take down full sized aircraft, hyper-sonic weapons and ballistic missiles. Timeline: 2030. Even at 30-50 kW (e.g., the earlier AN/SEQ-3 LaWS on USS Ponce), lasers can target helicopters or manned aircraft to cause crashes by frying sensors or engines. Scaling to hundreds of kW extends range and lethality against faster, larger aircraft.

I'm pretty sure Israel has them active. In June there were many wooshes (i.e. interceptor fire) I heard from my home. Now I'm not hearing any, but am hearing what sounds like short high pitched whines (sort of like coil whine). I've been wondering if that is the HEL powering up for each shot.

Its not clear to me that this is generally worthwhile, even if it is very cheap per-shot; 6 targets at ~100m/s are already enough to overwhelm if the laser gets to engage those targets over 2km of their flight path (with a 4s dwell time).

If your laser emplacements are somewhat expensive and only lightly armored, you might end up in a situation where your opponent happily throws cheap drones, 10 at a time, straight at your defense and still comes out way ahead financially.

Israels situation is quite unique in that it is very small, but gets exposed to imprecise indirect fire a lot, so what works for them might be a really bad investment for the restt of the world.

What’s the cost of a single laser? Russia is launching hundreds of those per attack, over a large territory. With a range of 5-7km you’d need _a lot_ of lasers to effectively cover a reasonably large city.

What’s the cost of a single laser?

No idea. I would imagine one would have to call, negotiate, kvetch, negotiate, stall, and so on.

It doesnt have to be perfect, just better than the next alternative.

If we take 4 million per interceptor at fact value, you can compare them on cost basis. More area coverage for less money would be a potential benefit. Alternatively, reusability could be a benefit if we expect prolonged conflicts or many more of these situations in the future.

perfect is the enemy of the good

Cost per shot including the development and unit costs amortized over the service life of the weapons system? Or is that just the cost of the energy that got pumped into the laser?

That cost per shot is just the energy utilized by the C2 targeting and laser system. I have no idea what the overall cost of the system is. I have not yet found it published. I would wager the overall system is rather expensive but worth it to the point of using expensive ballistics to neutralize a 40k drone which is at risk of being overwhelmed.

I also can't find the accurate time to target stats, just overall dwell time.

Is the cost per shot even relevant if you don't include value of the saved property?

Yes. To compare to alternative defenses.

yes and no. Imagine they have 100 40k drones. Imagine, if a drone hits it will destroy $10mil in property. So your $100k or even $500k interceptor looks cheap.

However, they have 100 of them (so spend 4mil). so you might have to spend (if say 100k each). 10mil to protect your 10mil in property (and more if the interceptors cost more).

If on the other hand you can get the cost down to pennies (minus R&D costs), this is no longer part of the calculus.

I was thinking about this the other day when watching a video about Chernobyl.

They flew countless helicopters over the exposed reactor core and because this was 1986, helicopters didn't have a million sensors or electronics in it. It was entirely mechanical. Effectively all in-use aircraft nowadays could not complete such a mission as the electronics would be rendered null almost instantaneously, even with ECC, etc.

Do these high energy lasers fry the electronics, or are they able to simply ignite and burn holes through the aircraft?

I had to vouch your comment as it and most comments from your account are auto [dead].

The lasers can fry sensors like I mentioned. They can also burn holes in the body of the aircraft and damage engines. I think you may be conflating the modern glass displays with the sensors themselves. In many cases the actual sensors have not changed that much in terms of being vulnerable to directed energy weapons. The energy being emitted from Chernobyl was gamma radiation which at high enough prolonged exposure can cause bit flips. The two TU-16 bombers that seeded rain clouds around Chernobyl were not affected at all by the gamma radiation and I doubt modern aircraft would be affected just flying over it.

Some time log out and view your comments [1] as almost all are auto [dead]. A new account could be a fresh start.

[1] - https://news.ycombinator.com/threads?id=wiredpancake

Then again.. maybe dang was on to something…

https://news.ycombinator.com/item?id=47159666

https://news.ycombinator.com/item?id=47069736

https://news.ycombinator.com/item?id=47067723

https://news.ycombinator.com/item?id=47054551

Oh good catch. I did not go back far enough. They should create a new account if they are chill now.

No. This person should not try to circumvent moderation by creating new accounts. They should ask the moderation team for reinstatement of normal posting privileges, but be willing to accept a refusal. They've behaved appallingly.

I havnt seen this before Does (dead) mean they got downvoted or that everything they write is voided? How do you know what they wrote is appallingly bad?

Turn on "showdead" in your profile and you can see what they wrote. Without it, you just see that it's dead.

Can be either. We know because receipts were provided upthread.

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