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China: "Laser AK-47" assault rifle said to be manufactured; experts skeptical

Chinese researchers developed a prototype laser assault rifle, said to have a non-visible beam that can set fire to skin and clothing up to 800 meters away. The ZKZM-500 weighs about the same as an AK-47 at 6.6 pounds, can fire more than 1,000 shots on a rechargeable lithium battery pack, and will cost around USD $15,000 each. The rifle, from ZKZM Laser in Xian, is allegedly ready for mass production, to be sold only to Chinese military and police units.

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The July 1 2018 report appeared the In South China Morning Post. It quoted a “researcher who had [taken] part in the development and field testing of a prototype at the Xian Institute of Optics and Precision Mechanics at the Chinese Academy of Sciences in Shaanxi province. The source said “The pain will be beyond endurance.” Another researcher said that because the beam is invisible and noiseless, “nobody will know where the attack came from. It will look like an accident.”

A technical document stressed the “non-lethal” nature of the laser rifle, listing attacks such as burning the banners or clothing of “illegal protests”.

The laser capability claims were disputed, however, by numerous news outlets.

TechCrunch writer Devin Coldewey first noted that military laser systems capable of delivering damaging heat over hundreds of meters require “on the order of tens of kilowatts, and those have trouble causing serious damage.” He calculated that a Tesla Powerwall using lithium ion batteries produces a few kilowatts of power and weighs over 200 pounds. (The complete laser rifle weighs 6.6 pounds.) Coldewey said the problem was atmospheric attenuation of the laser beam which is “non-trivial at anything beyond, say, a few dozen meters. By the time you get out to 800 [meters, the laser’s claimed range] the air and water the beam has traveled through [are] enough to reduce it [to] a fraction of its original power.”

The Daily Mail quoted Dr. David James, a Cranfield University lecturer on electronic warfare. James said that a non-visible infrared beam has “the ability to burn clothing and skin at up to 500 meters … with modern laser materials.” But he also noted ways to combat the laser’s beam, such as wearing clothes that are lighter colored, reflective and/or fire-retardant. Atmospheric moisture — rain, snow, fog, mist — would block much of the beam. And a person could move or turn to avoid prolonged contact with the beam, reducing the burning effect.

Drake Anthony, a hobbyist who has built powerful 40-watt and 200-watt laser guns, also disputed XKZM Laser’s claims. Anthony posted a YouTube video called “Debunked” under his username “Styropyro”. Popular Mechanics summarized the Styropyro video this way: “For starters, it's hard to find a theoretical wavelength of laser that fits the report's laundry list of claims: that the beam is invisible, can pass through glass, can light clothes on fire, and can burn skin. Infrared lasers can light matches, for instance, but are simultaneously harmless to human skin. A laser that lives up to the hype would have to hit a tiny frequency sweet spot, one that's made even smaller by the Geneva Convention's prohibition of laser weapons that blind…. Even with those issues set aside, the laser is also suspect for its impossibly light and compact design. Assuming no sci-fi power source is involved, the batteries to power such a weapon would need to weigh four or five times more than the entire gun's reported three kilogram weight.”

To counter the criticism, ZKZM Laser on July 4 2018 provided the South China Morning Post with a video from a May 2018 test of the laser rifle, showing it igniting paper, clothing and a tire.

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Testing the laser rifle on a rooftop in Xian by aiming at a wooden board at the edge of the roof (inside yellow rectangle). Range to the target was not given.

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The videographer then walks from the frame above, across the roof in an unbroken shot. Nineteen seconds later, this is the damage to a piece of paper stapled to the board.

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The videographer continues getting close to the paper. It is about 24 seconds from the first frame above, to this one.

Sebastien Roblin, writing at the National Interest, stated “Obviously, the Xi’an institute may have made a technical breakthrough, but a thousand-meter range, gas-tank piercing ZKZM-500 that weighs only seven pounds seems to strain credibility compared to earlier lasers…. That the rooftop laser demonstration appears to have occurred at below 100 meters range may support the notion that the ZKZM-500 is capable of inducing painful burns or heat combustion of certain materials at short distances—but it would likely produce more limited effects up to the claimed 1,000 meter range. This is because lasers lose coherence (or “bloom”) over distance due to intervening atmospheric particles, which is why weather conditions also have a major impact on laser performance. As for the battery-weight issue, in the July 4 video there is no clear footage of how the gun is being held or mounted. This invites speculation that the six-pound gun could be connected to a heavier separate powerpack or an outlet to achieve the necessary output for the carbonization-level attacks. Obviously, this would limit the rifle’s use in mobile operations.”

From the South China Morning Post (initial report July 1 2018, follow-up with video July 4 2018), TechCrunch, the Daily Mail, Popular Mechanics, and the National Interest.