March 29, 2008

Death Rays

Stupid Question ™
May 23, 2005
By John Ruch
© 2005

Q: Did the military ever really try to build a “death ray,” or is it just science fiction?
—Michelle, from the Internet


A: The militaries of all major world powers have definitely been interested in “death rays” since the 1930s. In fact, most of the early research on lasers was funded by the US Department of Defense.

However, the idea of using some kind of concentrated radiation as a killing tool has foundered on enormous cost, size, fragility, atmospheric scattering and a host of other problems.

While a “death ray” that could kill armies or destroy cities is not at all practical, lasers have successfully shot down planes, helicopters and missiles. But reliability and bang for the buck still hamper these limited uses.

The primary military uses for so-called beam weapons like lasers, microwave weapons and particle beams is targeting, sensor/computer jamming and blinding enemy soldiers. The only laser pistols the US Army uses are toys featured in an arcade game operated by recruiters at sports events.

The death ray genre typically begins with medieval legends of the ancient Greeks’ supposed use of mirrors to focus sunlight to destroy enemy ships. But modern military interest began in the 1930s with the successes of electricity and radio. The idea of using microwave radiation to bring down planes or kill large numbers of troops started to pop up in military minds.

The pioneering but increasingly eccentric scientist Nikola Tesla claimed in 1934 he had a system for hurling some type of electrically charged particles at great distances to cause damage. (Exactly how much damage is unclear; some press accounts suggest the kind of damage that would only be realized by nuclear weapons, while others say he proposed only freezing airplane engines and the like.) By 1940 he was calling it “teleforce,” though the press preferred “death ray” or “death beam.”

Whatever Tesla had in mind, he never demonstrated it. And the idea of a microwave weapon—which would produce heat in humans—similarly faded as it became clear the waves spread out too quickly over distance to cause any sort of personnel damage.

The potential for microwave devices as computer-jammers, however, remains significant. As of 1991, five US Army helicopters had crashed because nearby civilian towers carrying microwave signals had fried their systems.

This journey from supposed soldier-killer to sensor/computer-destroyer is the path taken by most death ray concepts.

The particle beam (charged subatomic particles with great velocity) and the laser (intensified light) came about in the late 1950s with major funding from the Defense Advanced Research Projects Agency (DARPA), the Defense Department’s research and development branch known for letting wild ideas flourish.

It’s doubtful researchers seriously considered the laser or particle beam would result in a hand-held ray gun.

And indeed, devices that could do that kind of damage are far too large, too expensive, too difficult to aim and require too much power for the job. Laser expert Jeff Hecht in his book “Beam Weapons” calculated that for a laser to burn a 1-centimeter-wide hole through a human body would take at minimum 100 times the energy of a conventional .45-caliber bullet, which does far more physical damage besides.

Lasers in particular did prove capable of bringing down thin-skinned drone aircrafts and missiles. As early as 1975, the Army in a test shot down planes and helicopters at range with a large laser mounted in a turret atop an armored personnel carrier.

However, outside test conditions, lasers are less reliable for such tasks, especially if the smoke of battle and scattering effect of the atmosphere at long range is figured in. And even with the successes, the exact reasons lasers brought down flying objects varied from burning an actual hole to jamming navigation hardware or software.

Lasers continue to be studied as missile-destroyers, including in the current version of a “missile-defense shield” against nuclear weapons. (A preposterous specialty X-ray laser cluster, which needed so much power it could only be powered by a nuclear blast, was one of the ideas behind the original “Star Wars” missile defense program.)

But targeting and frying sensors on weapons or satellites remain the main uses for lasers.

And lasers can blind not only mechanical sensors, but human eyes, too. As early as the 1970s, lasers were used to dazzle enemy pilots, with definitive use by the Soviets and the British. In the 1980s, the Army tested hand-held lasers codenamed Dazer and Cobra with the intent of dazzling or blinding the enemy.

The business of blinding enemy troops is generally frowned upon, but that side effect of laser targeting systems is not lost on troops in the field. Laser-blocking goggles and visors have become commonplace in the modern arsenal.

Particle beams can pack a wallop. As Hecht notes, lightning is essentially a particle beam. But, like lightning, they’re also unreliable in their targeting and effect. They’re probably much less useful than lasers. The Soviets raised the possibility of using a particle beam generator to create a truly devastating death ray by stimulating the atmosphere into releasing lethal secondary radiation—but as usual, that would be insanely inefficient and expensive. Full-scale nuclear war would be easier and cheaper.

Specialty use and general harassment appear to be the future of ray guns. The Army has explored the relatively feasible realm of infrared lasers than can painfully but not seriously burn exposed human skin. There is also military research into sonic weapons that could disorient or nauseate enemies, but the familiar problems of aiming and reliability have cropped up.

It is worth noting, barely, that conspiracy theorists have a variety of death-ray beliefs about the High Frequency Active Auroral Research Program (HAARP) facility in Alaska, which uses extremely high-powered radio to study the ionosphere. While such beliefs are encouraged by DARPA’s funding of HAARP, it has yet to lay waste to the countryside.

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