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Military technology: Laser weapons get real
- Retric 11y agoA surprising limitation on these systems is how short range they are. Ships and Aircraft regularly fire on targets that are over the horizon, but lasers are pure line of sight.
- ianstallings 11y agoTrue, but the horizon goes down as you go up ;) Besides those are just weapon delivery systems. Those same systems can be used to transport a laser weapon system to the area they want to attack (e.g. missile + laser, aircraft + laser)
- Retric 11y agoThese systems are huge, so you might get them in a drone but it would be a large target as in the size of 20 seat business jet to a full 747. Line of sight is ed: Nm.
- peterderivaz 11y agoI think in this formula the altitude should be in feet, while the result is in miles, so 30,000 feet actually gives 213 miles.
- deleted 11y ago[deleted]
- crymer11 11y ago"The distance to the horizon in miles from height of an observer is approximately equal to 1.23 times the square root of the height in feet." - http://www.davidsenesac.com/Information/line_of_sight.html http://www.davidsenesac.com/Information/line_of_sight.html
- trhway 11y ago>These systems are huge, not really - 10kw laser diode pack is something like laptop size. 35kw (as we have 30% electric to light conversion efficiency) light-duty generator with small motorbike engine - like another 70 kg. Add some other pieces - total will be under 100Kg.
- Retric 11y agoIn October 2012, the firm successfully used its 40-kW combined fiber-beam system. Not 10-kW and 40kw is on the low end of what you want. Worse, 100kg per 10kw seems optimistic. Anyway, as a first approximation if you’re dumping X energy on target with a 30% efficacy laser using a 30% efficient generator your net efficiency is at most 9%. So, you need to dump 11 times as much energy as you can get on the target. This is why most early designs focused on chemical lasers.
- mrec 11y agoProbably a silly question, but would it be even remotely feasible to bounce a ground- or ship-based laser off a drone-mounted mirror? Pretty sure the obstacles to positioning the drone/mirror precisely enough (and keeping the mirror clean enough) would be insurmountable, but couldn't help wondering.
- Retric 11y agoOnly in the rube Goldberg sense of a ridiculously inefficient system. Also, if you can build a mirror to bounce the laser you can use that same mirror to protect the target. But, N beams and N mirrors sidesteps this issue. PS: An amusing idea is to use a fleet of drones with mirrors to cook the target using sunlight.
- gliese1337 11y agoAlso, if you can build a mirror to bounce the laser you can use that same mirror to protect the target. Not necessarily. The attacker controls the focal distance of the laser. If they are using a mirror offensively, they can adjust the focal distance to ensure that flux is not destructively high at the location of the relay mirror, but is at the target. If you are trying to use the same mirror defensively, the attacker can simply consider that mirror to be a new armor target that needs to be destroyed before they can get at you, and adjust their focus to create unsurvivable flux at the mirror surface.
- Retric 11y agoTo be clear, I did not mean that as a total defense. Still mirrors can be useful in combination with other things. For example the target can use a high deflection angle to disperse the beam. AKA you beam's intensity is sin X and as it covers 1 / (sin X) area. So full intensity = 90 degrees, and at 10 degrees your down to 17.4% intensity. For something like a Mortar rotation can also be a significant benefit.
- cli 11y agoThe article states that the firm MBDA in Germany had helped to show that reflective armour, at least with mirrors, is not a good defense against lasers, as >any dust on the mirrored surface would get burned in, and lead to the destruction of the target even faster than with a non-reflective surface.
- ww520 11y agoI would imagine the laser loses energy quickly going through the atmosphere as the distance increases. Cloud, mist, rain, and dust all absorb the energy.
- baldfat 11y agoThe question is will it pop popcorn inside a house? A really large amount of popcorn?
- baldfat 11y agoHere the link I am referring to before I get 4 down votes. This "joke" actually is referring to something special. A 1980s movie about technology, military and academia. https://www.youtube.com/watch?v=rthHSISkM7A https://www.youtube.com/watch?v=rthHSISkM7A
- deleted 11y ago[deleted]
- skj 11y agojokes are never funny if you have to explain them. just let the reference sit, and make those who get it feel special :)
- baldfat 11y agoThat was 100% my plan but than I was at -3 votes. Figured if I got one more no one else would see it.
- resonation 11y agoSeriously, this community can be a cruel mistress sometimes.
- oldpond 11y agopew pew :) Couldn't resist.
- Jun8 11y agoAh, the sound of lasers in space! I find the way laser rays are depicted in movies interesting (other than the silly "bad guys use red beams" thing). They are generally shown as a "bolt" with a clear beginning and end that travels through space at a low speed (good compilation from Star Wars here: https://www.youtube.com/watch?v=QRJ9Evjm5Xs https://www.youtube.com/watch?v=QRJ9Evjm5Xs). This, I believe, is why spaceships have to at such close proximity to each other in battles, you have to see the laser beam bolt thingie go from ship to the other at that low speed. This also opens up the possibility of dodging laser beams. Now, it could be that these are not really laser beams but particle beams (http://en.wikipedia.org/wiki/Physics_and_Star_Wars http://en.wikipedia.org/wiki/Physics_and_Star_Wars). BTW, I recently found that sound can travel in space, albeit very very inefficiently: http://physics.stackexchange.com/questions/162184/what-is-the-speed-of-sound-in-space http://physics.stackexchange.com/questions/162184/what-is-th...
- oldpond 11y agoI like the way they did it in Eve Online with the mining animations. The "bolt" animation should be plasma weapons, and "pew pew" seems a bit too cute and cuddly for that.
- megrimlock 11y agoFor a reference point on how far this tech has come: https://en.wikipedia.org/wiki/Soviet_laser_pistol https://en.wikipedia.org/wiki/Soviet_laser_pistol
- irl_zebra 11y agoI think this one would be an even better reference point to show the gulf of effectiveness between where we were and where we are now: http://en.wikipedia.org/wiki/NES_Zapper http://en.wikipedia.org/wiki/NES_Zapper
- dm2 11y agoHere is one from a few years ago: http://en.wikipedia.org/wiki/Personnel_halting_and_stimulation_response_rifle http://en.wikipedia.org/wiki/Personnel_halting_and_stimulati...
- stevenrace 11y agoWhile that was designed in 1984, the US DoD had successfully tested laser weapons over a decade earlier: 'The first was in 1973 when the USAF shot down a winged drone at their Sandia Optical Range, New Mexico, using a carbon dioxide GDL and a gimballed telescope. Subsequently, in 1976, the US Army employed an electrically pumped HEL to destroy a number of winged and helicopter drones at the Redstone Arsenal in Alabama. The USN, in March 1978, then engaged and destroyed an Army TOW missile in flight' [1] The first targets destroyed from an airborne platform (KC-135) were in 1979. [1] http://www.ausairpower.net/APA-DEW-HEL-Analysis.html http://www.ausairpower.net/APA-DEW-HEL-Analysis.html
- codewithcheese 11y agoSerious question: is there a recorded case of a laser weapon being used in combat?
- woodman 11y agoYes, a US soldier was blinded by an Iraqi in Desert Strom [0]. The article doesn't cover it, but as I remember it, the laser was part of a tank laser range finding system - not a purpose build blinding device (the Chinese were openly producing such weapons at the time). Another class of weapon would be a dazzler [1], and those are used frequently. [0] http://www.ipsnews.net/1995/09/disarmament-blinding-laser-weapons-must-be-banned-now-red-cross/ http://www.ipsnews.net/1995/09/disarmament-blinding-laser-we... [1] http://en.wikipedia.org/wiki/Dazzler_(weapon) http://en.wikipedia.org/wiki/Dazzler_(weapon)
- codewithcheese 11y agoThanks
- ghostberry 11y agoI can't help thinking that in the anti-mortar role, there are very simple countermeasures that would severely reduce the laser's effectiveness. Reflective paint, ablative coatings, internal vacuum layer, heat insulation, thermally insensitive explosive and detonators, etc.
- cli 11y agoI think that demonstration was to show that the laser system can be useful against very cheap home-made mortars and rockets. The military would rather use a laser that costs tens or hundreds of dollars per shot to defend against mortars that cost perhaps several hundred dollars, rather than the current conventional methods that cost tens of thousands of dollars per shot.
- jessaustin 11y agoThe military would rather use a laser that costs tens or hundreds of dollars per shot... than the current conventional methods that cost tens of thousands of dollars per shot. Wait, I thought we were talking about the USA military? When have their weapons systems ever gotten cheaper? The only time they buy something cheap is when there is no more expensive option that does the same thing available (e.g. drones). If the only consideration is cost/shot, lasers will never be deployed. The point of TFA is that the new systems do things that haven't been done before, like stopping a mortar round in flight.
- walshemj 11y agoyes but most of the mortars this will be facing will be diy ones or at best ww2 era 80 or 120 mm fired by insurgent's who wont have these exotic rounds.
- gliese1337 11y agoReflective paint is surprisingly ineffective. In order to work at all, it needs to be tuned to the frequency of the attacking laser, and not get dirty, or scratched up, or otherwise gain significant imperfection in the finish, which is rather difficult to achieve when firing out a cannon and flying through the air. Even if those conditions are met, however, mirrors still make for surprisingly bad defense against weaponized lasers, simply because no mirror is 100% efficient. The 0.1-ish% of a well focused, high-powered weapons laser that doesn't get reflected by a ridiculously high quality mirror on initial contact will still damage and deform the mirror, thus allowing more and more of the laser's power to be deposited in the target with increasing dwell time. Laser weapons avoid destroying their own optics by, first, using optics tuned exactly to the specific frequencies the weapon is designed to fire, and second, by using relatively large focusing mirrors / lenses which keep the power/area on the weapon optics below dangerous levels. Even so, real laser weapons have ridiculous cooling requirements to keep from destroying themselves with waste heat, which keeps their efficiency rather low. There are other countermeasures that can be used against lasers, to be sure; mirrors just ain't one of them.
- forgotAgain 11y agoAnother Pentagon budget cycle has begun. Seemingly forever US companies have put out puff pieces about technology which are then regurgitated by the media. It's all about getting the public to support the ever increasing US military budget.
- jessaustin 11y agoLooks like Nature is on-board with the effort this time around! Perhaps some editors are looking forward to posh think-tank appointments?
- antmaper 11y agoJust paint the missiles with reflective paint.
- pingou 11y agoFrom the article: "MBDA's tests have also helped to debunk the science-fiction idea that reflective armour would defend against laser weapons. They found that any dust on the mirrored surface would get burned in, and lead to the destruction of the target even faster than with a non-reflective surface." gliese1337 also explained it more in details in this thread.
- antmaper 11y agoI need to learn to read before comment lol
- seanflyon 11y agoAblative paint is another option, though it just means that it takes a bigger laser or more time to destroy.
- ChuckMcM 11y agoThe interesting bit is that folks realized that you can combine lasers without having them be coherent and still get decent amounts of power on target. That made a lot of off the shelf lasers much more viable. The key though is the $10 a shot versus $100,000 a missile. That is what will change the equation permanently. If the price of operation of a PATRIOT type missile battery (or Israel's IRON DOME) goes from $1M/day in combat to $100/day, you will see them deployed a lot more frequently.