86 Comments
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Dilandu's avatar

Iron Beam is a fiber-optical laser cannon of IR spectrum range (not clear, which exact frequency range is used), with peak power of 100 kilowatt (apparently non-pulsed), and focusing ability specified as "coin at 10 km" (i.e. about 2-3 cm diameter of the spot). The system seems to be containerized, have two turrets per unit - presumably, it could either pump full power through one turret, using the other to track next target, or split the beam between both turrets to engage two targets simultaneously. Current model lack its own detection and tracking radar, instead relying on Iron Dome cRAM to provide it with targeting data.

Aviation Sceptic's avatar

CDR Sal, great article for several key reasons. You summarize the good and bad of lasers accurately and succinctly. Targeting, dwell time, power requirements, atmospherics, are, as you note, variables in the equation that we have struggled with on the early systems fielded. Solving them requires focus, and Israel's existential reliance on defensive systems THAT WORK is focused like no other nation. If anyone can solve these problems, they are a great candidate. I'd note that doing the development for their nation vice fulfilling the MOPs and MOEs on an RFP probably increases the likelihood of success. Lives over profit? Who'd a thunk it.

OrwellWasRight's avatar

"Solving them requires focus"

did you do that on purpose? :)

Aviation Sceptic's avatar

Wish I was that smart...(-;

BK's avatar

The laser defense is only viable for low-density missile and drone strikes. The target dwell time is inherently a constraint that is unlikely to be solved sufficiently for it to be useful.

Laser power is another thing.

Perhaps lasers should be used where their strength is the strongest: target illumination.

By multiplexing a single laser beam rapidly amongst hundreds of targets, the reflected laser frequency could be used to guide small anti-drone/missile shells and explode them in the vicinity of the target swarm. Smart shells and bullets are really the way forward.

[1] https://insidedefense.com/insider/air-force-considering-laser-guided-rocket-capability-take-down-enemy-drones

Captain Mongo's avatar

At last, the long awaited Death Ray may be here?

Flight-ER-Doc's avatar

This is the 21st Century I was promised!

Flight-ER-Doc's avatar

My impression - which can certainly (and likely is) wrong, or at least incomplete, is that sheer electrical power is a common theme in why warships cannot be upgraded - simply no room for more generators, more power conduits. So the US cannot simply add-on new weapons systems that require power, willy-nilly. This affects aircraft as well, to a certain degree (mass/size is more of a factor), and land-transportable systems.

Lasers are currently limited by two engineering challenges - power to run them, and materials that won't melt after a shot or two without significant cooling (which, requires MOR POWR).

So the development of Naval weaponry has a 'natural' bottleneck that seems to prevent development, testing and adaptation. Time for this to end. Ship designers need to factor in lifetime requirements of 5x or 10x the power loads they estimate at hull-wetting. This makes sense from a maintenance standpoint (lots of redundancy, and long-lived components at least for the first half of the life cycle), and is easily achievable today with nuclear power - if the BBG needs 2 reactors worth of power, then put 4 reactors in, and quit pretending that some oil fired plant will do the job. Likewise, a new DDG or CG or even a FFG will run just fine on dinojuice... Pay for the reactor up front, enjoy the nuclear powered air conditioning.

Dilandu's avatar

What do you means by "materials that won't melt after a shot"? Why should laser mirror melt? The energy density on mirror is low; the beam is spread over large surface. What makes laser beam deadly on target, is that it's focused into a very small spot on target, reaching enormous energy density.

Flight-ER-Doc's avatar

Yet designing high power lasers requires materials that don't simply melt (or shatter) when they are focusing.

Dilandu's avatar

Again, why would they melt, if the energy density on mirror is low?

Alan Gideon's avatar

It's not the mirror, it's the "thing" that is creating the initial laser "beam". The last time I was involved in this type of beast, the mirror was used to direct the beam. The project I was part of used very serious diodes, like LEDs on steroids, to create the beam. And those needed a massive flow of chilled water, in naval engineering parlance, to prevent LED meltdown.

Dilandu's avatar

Basically yes, the modern lasers are fiber-optic. But their high power is achieved by putting together a lot of moderatedly powerful resonator modules, each running at tolerable energy level, and combine beam out of them. It presents challenges, of course; the beam combined of multiple sources is less stable and regular than the beam from one powerful generator. But from the beam generation point of view, the use of multiple generators combining beams on main mirror is more practical - exactly because each individual generator isn't very powerful.

Alan Gideon's avatar

Thank you for refreshing my memory. My experience is about seven years old and some of the details had been flushed from my retired brain cells. ;-) My only part of the project was trying to cool the thing.

Bill's avatar

Power in to laser is only 15% efficient so 85% is waste heat.

Dilandu's avatar

Your data is very obsolete, modern lasers are 40-45% efficient (some experimental lasers push all the way to 55-60%)

Bill's avatar

I was referring to chem lasers. The fiber optic ones are 30-40 % for first shot at room temp. Goes down as it heats up. But yes lab units in AC rooms can go over 50%.

Dilandu's avatar

Chemical lasers are quite inefficient, true. But as far as I know, by now chemical lasers are considered to be outdated technology, with only a narrow sphere of implementation (their main advantage is that their beams are very stable on frequency)

MM's avatar

So optimistically only 40% is waste heat that has to be removed.

It's a 100 kilowatt laser. The article doesn't say if that the input or output, assume it's the input. Then you have to remove 40 kilowatts of heat from a very compact space.

Yes automobile engines do that, but the heat generation is over a rather larger volume, and distortion is less important.

MM's avatar

Not that large a mirror, lasers are pretty collimated already.

No mirror reflects 100% of the incident energy. What is not reflected is absorbed, heating the mirror. The total energy involved means the absorbed portion is significant.

It's also absorbed quickly, since that's what happens in a weapon. The absorption happens at the reflecting surface and takes time to diffuse to the supporting structure. This can distort the mirror, increasing the heat absorbed since this affects the focus and requires running the beam longer to affect the target.

So you need lots of cooling, and it has to do it in a way that doesn't also distort the mirror the other way.

Oh, and much of the energy doesn't actually come out the business end. The figures I've seen are 1-2% of the input energy ends up in the beam, but that was a long time ago. They've probably figured out ways to increase that.

But anything that doesn't come out in the beam has to be removed via cooling.

Dilandu's avatar

The power problem is perfectly solvable even for non-nuclear warships. Just use electric propulsion, with turbines/diesel working not directly on shafts, but on dynamos, powering the driving electric motors on shafts. You would have many megawatts of electric power avaliable, constantly flowing into driving motors; if you need to power lasers, you just re-route part of this power from motors to weapon systems!

corsair's avatar

Don't you need endless batteries to store enough energy to delivery the necessary pulse?

Dilandu's avatar

Nah, the modern lasers are efficient. They aren't 1980s power hogs. The modern fiber-optic laser have power transformation coefficient about 40%; i.e. you need about 250 kilowatt of electric power to fire the 100-kilowatt laser (of course, on practice the losses would be somewhat greater).

MM's avatar

My understanding is that the non-nuclear versions don't have enough spare power to run the lasers without doing things like slowing the ship down while they're firing.

They would already take some of the power generated by the turbines off into a generator for the electricity, this would just be all of it instead.

For all I know, maybe they do that already. It's what most locomotives do now and have for about a century. If they haven't it's for good reason.

Dilandu's avatar

Well, lasers likely won't drain so much power to render ship immobile, after all. Albeit full speed might not be achievable while firing.

MM's avatar

Firing offensively while moving may not be necessary.

But firing defensively while moving as fast as possible is entirely what you want. Moving out of the way, or running away faster than e.g. the drones can follow you is definitely something that has been used.

Which is why more warships need to be nuclear. There's no comparison in terms of the power you can generate in a compact package that will fit in a ship.

I suppose they haven't proposed an all-nuclear fleet for a couple of reasons:

- getting enough people that are good enough to run the reactors would be hard, and I don't know about the prospects for promotion if you go into the nuke path.

- Nuke ships are expensive to build, and made much more expensive by the mickey mouse lawfare that accompanies anything nuclear.

- Shipyards that can build nuclear ships apparently are also scarce, to the point where I think the reason the BB they're proposing isn't nuclear is mostly because building a nuke BB means not building a Ford carrier since they can't occupy the same yard.

- Bluntly the purpose of a carrier escort is to shield the carrier, which sometimes means you can't dodge.

Kevin's avatar

IIRC, a LM2500 generates about 30 MW of electrical power (varies by sub-model). Each is about the size of (but not the same as) a 40 ft cargo container.

MM's avatar

My immediate reaction was "then why aren't they using these in warships?" But it looks like they are being used, mostly to provide additional electricity.

I suspect problems with cooling, lack of opportunity for graft since it's been around for decades, and possibly fuel consumption.

When you use lasers as a weapon it does need a bit of change of thinking.

Weapons are a means of applying energy to the target in an undesirable manner (from the POV of the target).

Guns and missiles have the advantage that much of that energy has been created and stored in the propellant and warhead. You just need to set it off. There's some energy required to point the gun but it's much less.

For a laser you have to generate *all* the energy on the spot at time of use. Which is why they're famously energy hogs.

Maybe the new lasers are efficient enough that this isn't a show-stopper anymore.

George's avatar

I'm a little surprised no one is looking beyond their noses. I guess mirrors cannot deflect light. No sirreee bob.

Mike Brogley's avatar

All the harder parts of engineering for laser weapons boil down to one or the other aspect of power. Given a lasery-enough beam, the dwell time and tracking and shifty water-laden atmospherics for “keep zapping it until it goes down” shots are much simplified, as the energy on target happens much more quickly, and on the input end, given enough juice, the beam power and recharge and subsequent shot problems are all easier to address as well. Sure the optics are a challenge, and the whole thing needs to be salt water wave-proof for shipboard use, but power system are the big thing.

The only thing that really impressed me on the Zumwalt design was the attention reportedly paid to power systems, and one of my big uh-ohs on LCS was the “right sizing” of both designs shipboard power systems, for “efficiency”.

And again, power enough for big frikken lasers are a big frikken argument for the BBG becoming a BBGN.

Ed's avatar

“Fundamentals we keep turning to here”?

A pentagon acquisition system that rewards failed shipbuilding… other weapon acquisition scarcely better than the naval arms!

That Israel can do better than our pentagon after nearly 80 cooperating is iffy.

George's avatar

We're not supposed to notice the complete inventory of NATO equipment on display in cities all throughout Russia. They were the "gamechangers" if you remember correctly.

Nurse Jane's avatar

Happy 2026 and Forward March to the tune by Vaughn Monroe: “Sound Off”!

Welcome to Star Wars CDR Salamander. In 1985, Gus Chyba knew of my “Above Average Intelligence”, so he brought me to San Fran to study Laser and Holography.

Gus Chyba succumbed in 2016. I miss him terribly. His father, a humble mailman, was scooped up by the Nazi War Machine. Spent years in a Russian POW Camp, while Gus Chyna’s mother worked to send Gus to school, to become a “Brewmaster”.

At sea, yes, we have Atmospheric conditions, Electronic Pluse, wind and wave action too.

Best way to determine success, “Try it out!”.

Case in point… “War on Narco Trafficking”.

As far as “Incoming”… that’s that “Golden Dome Deterrence”.

Suggestion, thank you shipmate re: Private Funding, Let’s redirect the desired Washington D.C. Neptune’s Arch Monument adjoined to the Terraine. We don’t need “Pomp & Circumstance” at the moment, in my opinion.

Let’s appoint a Project Manager and Monies Auditor to your interest and mine, “The Laser”.

I’ll read more of your New Years Post…

It’s time to redirect POTUS from his Glamor & Glitz to our Naval Defenses. Very respectfully Nurse Jane

Mike Brogley's avatar

And this being yet another CONEX-form weapons system leads me to again consider the path proven by the Puller class ships for Something Sooner - would adding cranes and beefing up the power systems on that design yield a relatively rapid chock-full-of-all-the-CONEX-weapons afloat capability? Can a Puller keep up with the fleet? Or are there good-enough faster than the Puller’s tanker-based design container hulls that could go through the same iteration cycle faster than the someday-ships and unmanned follow along arsenalish drone hulls that the Navy really wants?

corsair's avatar

Navy has been fiddling with this stuff for over a decade now, AN/SEQ-3 LaWS was installed on USS Ponce and then Portland, which was then succeeded by HELIOS on USS Preble and ODIN on USS Dewey.

Does the money trough continue to get refilled without anything concrete or, deployed in numbers?

Rudeboy's avatar

They're closer than you think. UK has trialed its Dragonfire system and the first 2 are going on T45 destroyers in 2027, with more to follow.

Rick Bolin's avatar

Lasers … the longest weapons development program known to man. I’d be amazed if one is actually practical in a combat environment.

Rikard's avatar

Container ship with a nuclear reactor onboard, powering it and the lasers perhaps. Could be combined with a diesel engine for appearance' s sake.

Never mind that doing this paints a target on every container ship, necessitating mayhpas a return to those times where a foreign ship had to anchor X nautical miles outside and await insepction before being let into port.

(Hm, come to think of it, why not go back to that anyway?)

Small fire-and-forget drones carrying small lasers targetting the eyes/optics of enemy soldiers and vehicles was an idea that was bandied about in the early 1990s in pop-culture, so odds are it was being discussed at least a decade earlier, somewhere - remember all the old magazines in the "speculative technology"-genre?

And wasn't there an American wargame-exercise where the American admiral playing the Iranians sunk an American fleet by swarming it with high-speed motorboats doing kamikaze-runs, said exercise then being cancelled and re-done because the winning strategy was deemed cheating?

(Could be misremembering - probably am, to tell the truth.)

I'm holding out for bottom-of-the-ocean crawling fortresses armed with sonic ball-busters, seismic shock impellers and drill-down capable multi-megaton vehicles - imagine being able to wipe out an enemy by causing a 1 500 feet high tsunami hitting his coast.

Sci-fi? Only until someone builds it and tries it.

If I was a Chinese war-planner I would at least entertain the fantasy of being able to trigger the entire San Andreas fault in one go, or make the Hawaiian hot-spot go off for real.

It's like with some things: 99.9...9% of the time it won't happen or doesn't work.

But when it's something that only needs to work once?

Sandy Daze's avatar

You would be referring to Millennium Challenge 2002 (MC02) a major simulation conducted by the U.S. Joint Forces Command in Suffolk, Virginia, from July 24 to August 15, 2002.

The gent who peed on everyone's snowcone was retired U.S. Marine Corps Lt. Gen. Paul Van Riper, (Vietnam vet and former commander of the 2nd Marine Division.)

More available here:

https://grok.com/share/bGVnYWN5_f737cd51-6489-4b2f-86cd-3e69bad5a09d

Ron Snyder's avatar

My first exposure to General Riper was in his criticism of the fubar known as Force Design 2030. I agree with his view of 2030.

"Retired Marine Lt. Gen. Paul Van Riper is a prominent critic of Force Design 2030, arguing it dangerously reduces the Marine Corps' combat power by divesting tanks and heavy artillery, creating smaller units that can't operate as effective combined arms teams, and potentially making them vulnerable to targeting near China, questioning its ability to meet global combat needs and stressing it's a step backward, not forward, for the force. He believes the plan, focused heavily on naval integration for the Pacific, neglects the Corps' traditional role as a versatile, deployable force for other combatant commanders, risking the loss of essential capabilities for high-end fights.

In essence, Van Riper sees Force Design 2030 as a detrimental transformation that sacrifices enduring combat effectiveness and versatility for a narrow, ship-based focus, potentially undermining national security. ..."

https://www.youtube.com/watch?v=c6AC7NSyo4Y&t=32s

Aviation Sceptic's avatar

I was in the White Cell during that event. It was a lot more complicated than described. IIRC (and it was over 20 years ago) Van Riper did supposedly quit, but was told he wouldn't get paid, so never actually left the building. The BLUE commander was guilty of tactically unsound deployment, and one of the game "pucksters" was out sick. They had to leave the AA systems in manual because in auto they engaged each other. When Iran launched their attack, very few of the AA systems responded, hence the maritime massacre. What a merry time we had!

Brettbaker's avatar

Wasn't there something about motorcycle couriers delivering messages in 1/3 the time it would take in real life?

Aviation Sceptic's avatar

It was complicated. Exploiting the flaws in the mod and sim "federation" did not reflect the real world. Combining a large number of realworld "live" assets with exercise goals and objectives vs an experiment (which can fail) was very risky, and didn't go well. Meshing the mod and sim federation with constructive modeling and live assets in a mixed model and live environment proved to be beyond the capabilities of the time.

Ron Snyder's avatar

"It was complicated" sounds like an excuse. War is complicated. Life is complicated. Ginning up wargames to get a desired result is not complicated. "Exploiting the flaws...", another cop-out. You pretend that the wargame reflected the real world. You almost certainly know that few wargames actually reflect the real world. The Flags want a desired outcome, and that is what is reflected in many if not most wargames. Marines tend to be the most honest players because they still know that a grunt on the frontline with 1/16" of cloth for protection will pay the price for FOGO games.

Aviation Sceptic's avatar

No argument. Life, as you say, is complicated. Combining an exercise with an experiment is layering layers of complication on reality, making any conclusions drawn from the outcome...uncertain if not outright invalid. I always enjoyed working with MCWL, because they genuinely tried to get the most bang for their buck. In the White Cell we planned and executed the mechanics of the event based upon the objectives as defined by the stakeholders. We didn't write the AAR.

Rikard's avatar

Thank you!

I'm not in the least surprised it was a man with actual experience that tried to teach his peers and contemporaries a valuable lesson:

Whatever works, works.

Fleet Logic's avatar

"imagine being able to wipe out an enemy by causing a 1 500 feet high tsunami hitting his coast."

The Russians have imagined it, and it's not pure sci-fi now, as they've built it. - that's the point of their Poseidon nuclear torpedo. Whether it works or not remains to be seen... though if it does, I hope we don't see it.

Rikard's avatar

Now imagine 140 000 Starlink satellites being able to focus a ray of sunlight, just a tiny one per each one, on a single spot a hundred yards across. No need for a laser cannon if you can simply raise the ambient temperature over a battleship or fleet tender to several hundred degrees for half an hour.

I always wonder if these ideas came from early 1900s sci-fi first, and was then picked up by engineers into "Vergeltungswaffen", or if it was the other way around.

That's the trouble with imagination: people like you or me can imagine it and thinkfeel:

"I never want to see that"

Other kinds of people instead thinkfeel: "I really want to see that!"

Alan Gideon's avatar

Due to the manner in which lasers affect humid air, they end up creating a shaft of noseeum (TM) as they dwell on a CBDR target. One way to reduce that problem would be to have multiple ships with lasers, each firing at crossing targets rather than CBDR targets. Just a thought; I don't know if this possible solution has been tested.

Bill's avatar

It has been simulated. Getting each beam to hit with a few cm is hard unless under 1km.

Alan Gideon's avatar

I think I may not have clearly stated my idea. What I tried to say was that a group of ships could mutually support each other by firing on targets that are crossing for the firing ship, but CBDR for another ship. Think of three ships in a formation that forms an equilateral triangle. It the only useable formation, but one that gets the idea across. Each ship has to depend on the shooting of the others.

Lee's avatar

No one is going to like this in any way, shape, or form, but the need for a nuclear powered Laser Cruiser (CGNL) is evident. If lasers are the way to go to defeat threats, then power is the short pole in the tent. Let's not fool ourselves, LCS is a joke and will not have the sustained power for lasers in a high threat environment. This hull should replace the Tico-class CGs as the Anti Air Warfare Commander. One laser per hull is not enough. I don't know exactly how many . . . ten or so? But we need this to counter swarms of ASCMs, ASBMs, HSCMs, and drone swarms. Yes, the cost is high. Easily a couple billion per ship, but needed for AAW for CVBGs and MEUs.

The Drill SGT's avatar

How about going the other direction and having a couple of containers on many ship decks. Said containers, having roof openings like those Ukrainian containers that struck Russ strategic bomber bases. Our containers would, like CAM ships of 1941, release hundreds of 1 time use defensive drones?

Andy's avatar

The large surface combatant should be an energy combatant, not a vls focused ship. Keep on board that ehich can be resrmed or resupplied without any hoops. Radar, lasers, miscrowave, emals missile launcher or railgun maybe. Otherwise guns and RAM.

Bill's avatar

I was CE of a laser program 25 years ago. They don't work for fast multiple shots. Typical laser 15% efficient. So a 15kW in is only 1kW out. That's 14kW of heat. Get rid of it fast or no multiple shots. So cooling big issue and wasted power. Of course the atmosphere at sea scatters the light leaving so only a tiny amount on target unless it's close. Fast metal like a rail gun is better.

David Pawley's avatar

Maths correction: 15 kW in at 15% efficiency is 2.25 kW out, but your point stands.

Ahmed’s Stack of Subs's avatar

Phased plasma rifles in the 40 watt range?

David Pawley's avatar

40 watts is a dim bulb. That was an unfortunate choice by Cameron (or the scriptwriter).

OTOH our CO2 laser cutter at work is very effective at nominally 50 W.

MM's avatar

I have to wonder if that started out as "40 kilowatt range" in the first versions of the script but the actor had problems pronouncing it and the director said "Well, only the nerds will care and they'll have endless fun with this movie anyway."

You may have noticed Cameron isn't particularly science-focused.

Or maybe the writer wasn't science-focused either. It's not as much of a howler as Star Wars using parsec as a time unit and the endless attempts to refit that into making sense.

Sicinnus's avatar

Such items get argued on the balls to four watch. My personal opinion it that it was shortened for the actor and was actually 40 watt-hours. That works out to 144 kilojoules, or about the same energy as a 37mm M3 projectile. Kinda fits with the damage you see delivered in Kyle's dream scene.

I know - eff'n nucs always brining a slide rule to a perfectly good beer argument over a couple of San Miguels.

MM's avatar

Having thought it over, I think it also had to do with the scene.

I mean if you're the shop owner and you have someone Schwarzenegger's size as a customer and he says "KEEEL-o-watt" I think you, and everyone in the shop, are going to be (at least subconsciously) alerted.

Whereas the point of the scene was that the owner is not alert and is happy to get a good sale - until the Terminator suddenly kills him.

OrwellWasRight's avatar

Apparently enough people were upset about Han's boast that they refit the story with an explanation:

"In A New Hope Solo brags about doing the Kessel Run in 12 parsecs, which sounds wrong because parsecs measure distance, not time. In Solo, Han makes the Kessel Run by going through the Maw instead of around, saving time and decreasing the distance traveled (12 parsecs instead of 20)"

MM's avatar

Yeah I commented on this elsewhere, people are endlessly trying to no-prize it into something that makes actual sense.

OrwellWasRight's avatar

maybe he thought watts in the future would be like calories; the "K" is silent!

Poebel's avatar

Quick example - 250kw that easily fits in 20’ container footprint. And that’s not optimized for water cooled / ship based footprint. Can probably even fit 500kw with bespoke packaging and integrated fuel tank. Certainly

so in 40’ container

https://www.cat.com/en_US/products/new/power-systems/electric-power/diesel-generator-sets/106460.html