The Buzz

The Coming Laser Wars?

On June 26 an Apache helicopter successfully tested a high-energy laser pod on targets at the White Sands testing range in New Mexico—the first laser weapon ever employed by a helicopter.

As much as laser-armed helicopters might seem like they belong in a Command & Conquer video game, in reality they are joining a wide variety of ground-, air- and sea-based laser platforms—many of which may be entering service in the coming decades and a few of which are already operational. In fact, a new era of laser warfare may soon be dawning, thanks to lasers’ usefulness for countering two important weapons systems: drones and long-range missiles.

Films like Star Wars depict laser weapons as emitting short pulses of green and red light. However, the “phasers” depicted in Star Trek in the 1960s were arguably a bit more accurate. Real laser weapons project a coherent ray of directed photons (light) that strike their target virtually instantaneously. This beam often streams into the target for several seconds or longer as thermal energy builds up to destructive effect—although some “pulsing” lasers also exist.

However, unlike the weapons in Star Trek, the rays from high-energy antimaterial lasers for use in the atmosphere are silent and generally invisible, as they usually operate at an optical wavelength indiscernible to the human eye. And today’s laser weapons are more likely to burn a hole in a target or cause it to combust, rather than vaporizing it.

Why use a laser instead of a bullet, shell or missile? To begin with, lasers are highly accurate and quick acting, since they are fast as light and mostly unaffected by gravity. This could make them ideal for swatting down small, speedy targets, such as incoming rockets and artillery shells. Laser precision could also be handy for disabling ground or sea vehicles without killing their occupants. Of course, a soundless, invisible and recoilless weapon is also pretty stealthy—if you can get close enough to use it.

Most importantly, lasers could be very cheap. Contemporary missile-defense systems, such as Israel’s Iron Dome or the United States’ GMD antiballistic missile system, are much more expensive than the missiles they are designed to shoot down, making them untenable were they to face mass attacks. The same problem exists at the tactical level when considering how to counter the future threat of weaponized drone swarms: basically large flocks of small, expendable drones designed to overwhelm enemy defenses. While antiaircraft missiles may cost hundreds of thousands of dollars—or millions for antiballistic missile interceptors—the energy consumed by a laser weapon might cost as little as a dollar. For systems hooked up to a power generator, the “ammunition supply” could be virtually unlimited.

However, lasers do come with disadvantages that have held back their adoption for decades. To start with, laser energy tends to “bloom” or diffuse in an atmosphere, limiting maximum range—especially when obstructed by sand, smoke or fog. In fact, the relative lack of obstructive particles in space explains why they are considered ideal space-based weapons.

Furthermore, lasers may have difficulty burning through denser materials, and often require several seconds of continuous contact to inflict significant damage—which may not be enough time to disable heavier projectiles, depending on the power and engagement range of the laser as well as the speed of the target. In fact, development of laser-resistant materials and countermeasures has proceeded apace despite lasers having yet to enter widespread operational use.

Another consideration is that lasers create virtually no kinetic “pushback,” so if a laser can’t burn out a critical component on a vehicle or munition—such as a warhead, engine, heat shield, targeting system, or fuel supply—it may fail to stop the target from hitting friendly forces.

Finally, laser weapons require powerful electrical generators or dangerously volatile chemical fuels, as well as bulky liquid or solid-state cooling systems. These limitations pose serious obstacles to producing field-deployable lasers. However, recent advances in solid-state laser technology may offer a solution to limiting the size of the power supply, though they do require additional cooling measures.

There are also legal restrictions: the 1995 Protocol On Blinding Laser Weapons—part of the U.N. Convention on Certain Conventional Weapons—forbids the use of “dazzler” lasers explicitly designed to permanently blind the eyesight of adversaries. This came into force after several dazzler lasers were developed and even exported and possibly used, and it is rumored the Chinese Type 99 tank may still have such a weapon system despite the protocol.

Fortunately, the protocol appears to have been more broadly interpreted as discouraging the use of lasers as an explicitly antipersonnel weapon. However, it does not restrict the use of lasers against manned vehicles.

Indeed, lasers might be practical for disabling small ground vehicles, attack boats and aircraft. However, the majority of contemporary lasers are designed as defensive weapons to counter drones and enemy missiles and shells.