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Comment Re:It's a matter of time... (Score 1) 370

Let's assume for a moment that we're not going to replace all of our weapons with lasers. Your mirrored rotating fog-encased vehicle looks like a pretty attractive radar cross-section to the missiles and tracking systems we still have, and which are still going to be developed.

Let's also assume that laser development does not stop at the first version. You've got the systems necessary to defeat our 50kw red laser? Congratulations, let's try it out against this 150kw green laser. Don't spend too much time working on the armor for that one before you see our dial-a-wavelength version that hits the target with 7 different wavelengths at varying power levels if the target can last that long. We call that one Roy G. Biv, and Roy loves looking at things. Oh, you have reflective armor that can handle any wavelength? How about this rail gun projectile that can track your reflective armor and make course corrections in flight?

That's what irritates me any time we're discussing the next weapons systems under development. There's always someone to step up and shit all over it like the defense is so easy and no one ever thought of that.

Oh, you have a missile that can shoot down an ICBM? Well, that's completely stupid. All they have to do is encase the thing in 30 meters of pillows, and your missile is useless. We already have the technology to land a craft inside a giant air bag on Mars, literally all they have to do is put that on an ICBM (they're completely interchangeable, you know, I've seen videos) and all you've done is waste tax dollars.

C'mon, man. Between the Navy's rail guns and laser weapons we're finally getting into Freespace 2 territory. I know that any nerd like myself who played Freespace found themselves chasing a stupid little Shivan Dragon or Manticore or something that's dodging all over the place with your shots going everywhere except where the enemy is, and you're thinking that all you need is a laser and a computer to aim it. And then Freespace 2 comes out and you start yelling "THAT'S WHAT I'M TALKING ABOUT!" We're finally entering the age of general-purpose destructive directed energy weapons and there's no shortage of people who are going to step up and talk about how it's useless based on research that was conducted decades ago when the weapons themselves were impractical. It's 2017, the Navy is fielding these weapons (and no doubt developing their own counter-measures), and you're trying to use a program that was cancelled in 1993 as a reason why it's not going to work. Let's assume that the people working on the weapons are aware of SDI, and while we're at it let's also assume that SDI is about a hundred years down the road for people whose major capability is trying to field a swarm of small vehicles.

Basically what I'm saying is that this is badass, and I'm looking forward (in a technical sense, not a humanitarian sense) to the battlefield videos that show a laser system defeating any number of vehicles, with support from our existing arsenal of more conventional weapons and vehicles. Like I said, with most warfighting my interest in this is purely technical, I do not envy anyone who has to fire this or come up against it in a battle situation. Game-changing weapons like these tend to suppress war, when you have a division of tanks that each have a laser on them capable of destroying incoming anti-tank rounds, so that your tanks can't even get shot, then the game changes. Years ago we saw videos of laser systems detecting, tracking, and destroying incoming mortar rounds. This is great technology, this is the kind of weapon that saves lives.

Comment Re:It's a matter of time... (Score 1) 370

A reflective coating could provide a lot of protection.

You emphasized the wrong word, that sentence should look like this:

A reflective coating COULD provide a lot of protection.

I'm still waiting for a single demonstration of any kind of reflective or retro-reflective protective coating. Just a single video showing a higher-powered destructive laser being defeated by any kind of reflective coating at all. I realize the US military isn't going to release a demonstration of them defeating their own weapon, but I know they've done that research and I'm sure that there is plenty of room for amateurs to also produce similar demonstrations with destructive lasers that are less powerful than what the military is fielding. But, like anything else, until we actually see some practical demonstration all of this guessing about reflective coatings is just academic. It could be the case that the laser is working at such a high power that if the coating reflects any less than 99.9% of the laser energy, it's still enough to cause damage to the coating and a runaway effect that sees the laser eat through the entire protection in under a second. Like I said, without testing these things all we're doing is guessing. Yeah, a reflective coating *could* provide a lot of protection, but it could also end up being a very expensive way to manufacture and reliably deploy something that gives you another second of lifetime in the field.

Comment Re:It's a matter of time... (Score 1) 370

That sounds like a pretty hilarious idea. A mirror large enough to obscure the entire wing span of the drone constantly moving around a gimbled arm or something while the drone is in flight? What if the ship is the target, is the mirror going to obscure any targeting systems on the drone? And how about the effect of a flying object with a constantly shifting center of mass and changing aerodynamic qualities, how do you even fly that? Again, if these are the kinds of ideas we force other people to spend their time and money on, then that alone is a pretty good effect of fielding a laser weapon. You have a drone with a ridiculous looking rotating arm with a simple lightweight mirror on it, congratulations your drone can stay in the air for another second before the laser destroys the mirror and arm. Hope the R&D was worth it.

Comment Re:It's a matter of time... (Score 4, Interesting) 370

The reflective surface does not need to reflect the entire spectrum just the wavelength(s) of the laser.

I understand that, but it needs to reflect the vast majority of the incoming energy or else the imperfections in the surface are going to be fatal flaws. I'm not an astrophysicist, but from what I understand engineering a surface that is both highly reflective with no imperfections, and also sturdy enough to withstand use in wartime, tends to be difficult and/or expensive. It's not like the knee-jerk jokes we get every time there's a laser story where someone suggests that someone just needs to hold up a mirror they bought at a drug store and, voila, the laser destroys itself.

You can also add an ablative coating to the missile similar to a reentry TPS.

How much weight is that going to add to the missile? Then, how much fuel do you need to add to compensate for the additional weight of the coating? Then how much fuel do you need to add to compensate for the weight of the additional fuel? It sounds like you're redesigning a missile. If we force enemy forces to redesign their weapons every time we come up with something new, good. At least we're at the front of the arms race instead of trying to catch up.

I'm sure that you could surround a missile or warhead with ceramic tiles and get some pretty great insulation from a laser, but we're talking about several hundred pounds of additional payload here. At a minimum that means your warheads are smaller, which by itself is a pretty great effect of fielding a laser weapon.

Comment Re:It's a matter of time... (Score 4, Informative) 370

I think there's a certain amount of urban legend in that whole reflective surface defense strategy. First off, the surface would have to be nearly perfectly reflective. If there are any imperfections at all it seems like they would rapidly heat up, creating larger imperfections, and the runaway effect would quickly destroy any reflectivity. Granted, if it's a 50kw laser then it doesn't need to reflect very much for very long to damage someone looking right into the reflected beam, but I still think the usefulness and practicality of actually fielding a target with reflective armor which a laser would fire at is vastly overstated. It seems kind of silly to go through the trouble to coat a drone, boat, or missile in reflective material when it's probably only going to buy the target another second of life before the laser destroys the reflective coating.

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