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Israel rolls out laser defense system

reuters.com

51–60 of 250 posts

Re: Israel rolls out laser defense system

#52

Earlier quoted context omitted.

This is again a money play here, after all everything is a money play. Iron Beam (this system) is designed to intercept simple rockets, artillery, and etc for cheap. The total cost per shot is estimated at 2000USD overall (including life cycle of the parts, laser, etc) compared to 100000USD for Iron Dome missile alone. It is even more for more advanced stuff like Arrow 2, Arrow 3, or David's Sling (all, including Iro…

Automated counter-battery in addition to AD would be an interesting extra layer of deterrence.

And a PR nightmare. Shoot a missile from a school or a hospital, then afterwards the newspaper articles write themselves when the automated system retaliates. Radar data showing it was a missile launch site will always lose to pictures of mothers holding dead children.

Counter battery is also of questionable effectiveness when most launch sites are used only once.

Re: Israel rolls out laser defense system

#53

Earlier quoted context omitted.

>I will believe it when I see it. Focusing that much light on a small moving object, through layered and moving air, with an intensity to burn through metal would be an achievement. Burning through enough of that metal to degrade a falling rocket (as opposed to during boost phase of flight) is even harder. it's been working 20 years ago. it's just systems were too big. you needed 2-3 tracks to supply energy to laser…

Any foil will do, just as the JWST's sunshield is effective against all the wavelengths coming off the sun. Gold or silver is best, but aluminum foil from the grocery store is extremely reflective across all wavelengths we would call laser. Just giving the metal rocket a good polish would make a significant difference.

there is some difference, but I guess all the companies that sank billions into directed energy weapons missed that aluminum foil from shop can negate all their efforts

Re: Israel rolls out laser defense system

#54
post #30

Earlier quoted context omitted.

Sounds like that could be gotten around by using multiple lasers.

Multiple beams creates a different problem. Say your beam is 1cm across and you are aiming at a 30cm target. All your energy is in that 1cm. You don't much care where in that 30cm it hits so long as it burns through. But with two lasers, to be effective, each beam needs to hit the same sport on the target. Instead of a 30cm target, laser #2 now has to hit the 1cm beam of the first laser.

That, or also you get a shotgun effect with different damaged areas in a single target. Increasing the probability of destruction with less powerful lasers.

Re: Israel rolls out laser defense system

#55
post #32

I'm curious where the tipping point is, where the military response exceeds the financial cost of a political response. It's one thing to have tensions simmering on both sides of a border, it's another that one side feels wronged and is lobbing bombs over the fence. The fact that they're having to develop a laser defense system to defend against lobbed bombs seems like it's time to reevaluate political solutions.

No post body was provided.

Re: Israel rolls out laser defense system

#56
post #43

"If we can intercept a missile or rocket with an electrical pulse that costs a few dollars, we will essentially neutralize the ring of fire that Iran has set up" This sets up a steampunk scenario where the missile must be controlled by a mechanical gyroscopic guidance system, immune from electrical pulses.

This system isn't an EMP system. It heats the target until it disintegrates.

I think the rockets it has to defend against are already as low-tech as possible, too.

Re: Israel rolls out laser defense system

#57

...and then what. What will they do when the rockets get faster, shinier, more erratic in flight...or any of the other things mentioned on this thread? I'm not going to pretend I have the solutions to the Arab Isreali conflict, but this is at best temporary. My best guess is the long term solution (if there is ever one attempted) will be more related to why people are motivated to launch rockets at their neighbours.

These "advanced" rockets will be more costly, which means your more limited on how many you can afford to fire. Thus Israel can intercept these "advanced" rockets with other solutions: Iron Dome, Arrow 2, Arrow 3, and David's Sling.

The Iron Beam is the low cost per intercept solution, meant to intercept cheap unguided ballistic rockets.

Re: Israel rolls out laser defense system

#58

...and then what. What will they do when the rockets get faster, shinier, more erratic in flight...or any of the other things mentioned on this thread? I'm not going to pretend I have the solutions to the Arab Isreali conflict, but this is at best temporary. My best guess is the long term solution (if there is ever one attempted) will be more related to why people are motivated to launch rockets at their neighbours.

IIRC (based on hard SF laser defece discussions) there is no perfect mirror, so pump enough MW/GW into it, even just for a short burst and the thing will start to melt or outright vaporize from the bit that it will always absorb.

Then it won't be so shiny anymore, absorbing even more energy and so on, until it stops being a solid object.

As for erratic flight paths - a physical object can't aim to match the beam steering capabilities of a group based stationary laser, given any realistic currently available propulsion or steering technology. It would need to do crazy high g & high energy manufacturing yet from the PoV of the laser its moving just a couple degrees if at all. As unlike a physical interceptor the laser beam moves at the speed of light and thud the point of aim can more more or less instantaneously.

Re: Israel rolls out laser defense system

#59

I will believe it when I see it. Focusing that much light on a small moving object, through layered and moving air, with an intensity to burn through metal would be an achievement. Burning through enough of that metal to degrade a falling rocket (as opposed to during boost phase of flight) is even harder. For all the talk about cost reduction, have a look at what realworld laser armor costs. Painting the nosecone of…

At the current power level, this laser is mainly useful against drones. There is a limit to how much laser power you can shoot through the air. When the threshold for breakdown is exceeded, a high density plasma is produced which is opaque to visible and infrared wavelengths and thus absorbs the laser radiation. The moon does not have this laser power limit, but moving Tel Aviv to the moon would quite expensive and y…

Aren't there wavelengths available that wouldn't superheat air, but would be absorbed by a missile?

Re: Israel rolls out laser defense system

#60

I will believe it when I see it. Focusing that much light on a small moving object, through layered and moving air, with an intensity to burn through metal would be an achievement. Burning through enough of that metal to degrade a falling rocket (as opposed to during boost phase of flight) is even harder. For all the talk about cost reduction, have a look at what realworld laser armor costs. Painting the nosecone of…

At the current power level, this laser is mainly useful against drones. There is a limit to how much laser power you can shoot through the air. When the threshold for breakdown is exceeded, a high density plasma is produced which is opaque to visible and infrared wavelengths and thus absorbs the laser radiation. The moon does not have this laser power limit, but moving Tel Aviv to the moon would quite expensive and y…

THEL was shooting down mortars, shells and rockets at early 2000s
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