Decades to ‘ZAP’

Everybody—at least, every branch of the military—wants a laser gun. The theoretical possibility of a silent beam of energy that turns enemy weapons to toast has been explored in the pages of AL&T magazine for decades. With high-energy lasers on Stryker combat vehicles and an Apache helicopter downing drones in tests, it now seems a matter of time before lasers are in use on the battlefield.

by MS. Mary Kate Aylward

Lasers, synonymous with precision from eye surgery to targeting, have long held out the possibility of an elegant and cheap solution to some of the messier, more expensive problems of war. A bomb is a single-use weapon; a laser is reusable. A laser weapon can disable a vehicle at a distance without blowing it up, preserving lives and intelligence, and can do a host of things a bullet can’t, or that a bullet can do but with a big risk of collateral damage. It can blind a surveillance camera, disable communications networks, shoot down a rocket fired from an approaching boat.

A laser weapon needs a lot of power but doesn’t need ammunition, which frees up a whole chain of resources. No need for bullets means fewer vehicles in a supply convoy and less storage space needed. Theoretically, a weapon that travels at the speed of light could also shoot down a missile traveling faster than the speed of sound, boosting the ability of current missile defense systems to intercept new hypersonic missiles.

These benefits eluded the defense community for decades. In the July-August 1966 issue, Army AL&T predecessor Army Research and Development Newsmagazine ran a summary of a paper presented at the Army Science Conference by Feltman Research Laboratories exploring the ability of chemical reactions to power a laser beam. The detonation of a cyanogen-oxygen mixture in small test vehicles looks promising as a pump with military applications,” the article noted.

Interest in and the feasibility of laser weapons has waxed and waned since then, and the magazine archives chart this: In a May-June 1976 article, Dr. George H. Heilmeier, then director of the Defense Advanced Research Projects Agency (DARPA), said that whether the Soviets could use lasers to disable the American satellite network was the No. 1 question DARPA was exploring. Tangential references to directed-energy weapons (the technical name for high-energy laser weapons) and particle beams crop up throughout the ’70s and ’80s. In the March-April 1990 issue, Army Research, Development and Acquisition Bulletin, in a comprehensive survey of Army technology, named directed-energy weapons as one of 13 key fields where the Army needed to invest in the technology base’s ability to do research. This list was prompted by real fears that the United States was close to permanently surrendering the technological advantage to the Soviet Union.

Of course, during this time low-energy lasers became common across all kinds of weapon systems to mark targets and guide conventional ammunition. But high-energy lasers that don’t just guide another weapon but are the weapon themselves remained elusive.

Now, though, the Army has high-energy lasers zapping test targets from multiple platforms. (For reference, a 5-kilowatt laser is equivalent to about 5 million handheld laser pointers.) In Army tests, directed-energy weapons have been mounted on helicopters and cargo trucks and have melted truck engines from a mile away, as well as drones, laptops, small-caliber mortars and other projectiles. “The technology is coming of age as a realistic solution for ground platforms against small, close-in threats,” such as boats and drones, said Paul Shattuck, director of Lockheed Martin Space Systems Co., in an interview with Defense Systems published in June 2016.

THE SCIENCE IS THERE
It has been a long time coming. “We first determined we could use lasers in the early ’60’s. It was not until the ’90’s when we determined we could have the additional power needed to hit a target of substance. It took us that long to create a system and we have been working that kind of system ever since,” Mary Miller, then-deputy assistant secretary of the Army for research and technology, told military-news website Scout Warrior in 2016.

Over those years, the focus shifted from chemical lasers, which are cumbersome—a Boeing 747 carried the military’s last chemical laser—and risk toxic spills, to the more stable solid-state fiber laser, generated by fiber optics. “That’s one of the advantages of a fiber laser; you can dial the effect by applying more or less power. As an example, we can vary power to blind a camera on a drone, take out the camera or bring down the entire drone,” Shattuck noted.

Industry and DOD experts alike agree that the science is there to operationalize directed-energy weapons. The U.S. Navy’s amphibious transport dock USS Ponce has carried a 30-kilowatt laser weapon system known as LaWS since 2014 for testing. (Because a laser weapon draws a lot of power, larger platforms like ships and planes were a more obvious starting point than most Army vehicles.) It’s effective against drones and small vessels, but it would need more kilowatts to defend against anti-ship missiles; the Navy awarded Northrop Grumman Corp. a $91 million contract in 2015 to develop the next generation of the system, with a goal of demonstrating a 150-kilowatt seaborne weapon in 2018.

The more kilowatts a laser has, the faster it can burn through targets, the better it can pierce through obscurants s as dust, smoke and fog, and the better chance it has of burning through any reflective material (like a mirror) protecting a target. U.S. Air Force transport planes are fitted with lasers as an infrared countermeasure, as are U.S. Marine Corps CH-53 helicopters.

It appears to be a toss-up whether money or power is the biggest remaining challenge to getting directed-energy weapons onto the battlefield. Directed-energy weapons require a lot of … energy. To produce a 150-kilowatt beam, for instance—what researchers think is necessary to begin to counter aircraft and cruise missiles from farther away—requires 450 kilowatts of power. How to generate enough power without making the laser too big to mount on any platform is a persistent stumbling block, though certainly not unique to laser weaponry. How to store that power for mobile weapons is a second hurdle.

Lasers are expensive to develop, though cheap to use once developed. In 2012, DOD retired the Airborne Laser Testbed, its last effort to weaponize chemical lasers, in favor of lasers powered by more renewable means, after spending $5 billion. The high-energy laser weapon system that the USS Ponce carries was part of a $40 million research effort. But Navy officials estimate that each shot of the laser weapon aboard the USS Ponce costs 59 cents, for example, compared with the hundreds of thousands of dollars it costs to fire a standard missile interceptor or the approximately $115,000 for each HELLFIRE missile dropped from an Apache helicopter.

X MARKS THE SPOT
Spc. Brandon Sallaway, fire support specialist and forward observer with the 2nd Battalion, 12th Field Artillery Regiment, points to a sticker on a Stryker equipped with the Mobile High-Energy Laser (MEHEL), which he helped evaluate in April at the Maneuver Fires Integrated Experiment at Fort Sill. The stickers represent the number of drones the MEHEL has hit, and Sallaway was the first Soldier to use the weapon to take down a target. (Photo by C. Todd Lopez, Army News Service)

FROM LAB TO TEST
Over the past three or four years, the Army has gotten pretty good at shooting down drones with increasingly powerful laser weapons mounted on ground vehicles, as the result of several programs: the High Energy Laser Mobile Test Truck, for which Boeing Co. mounted a 10-kilowatt laser on a heavy cargo truck; and the Mobile High-Energy Laser, which was the first integration of a high-energy laser onto an Army combat vehicle. The Stryker-mounted 5-kilowatt laser weapon took down about 50 drones in an April test at Fort Sill, Oklahoma.

“We did a lot of preparation … seeing if we could track the airborne targets among ground clutter,” Adam Aberle, who runs high-energy laser technology development and demonstration for the U.S. Army Space and Missile Defense Command/Army Forces Strategic Command, told defense reporters after an April 2016 demonstration at Fort Sill. “We absolutely blew lots of stuff up.”

The next frontier in terms of platforms appears to be airborne laser weapons. On June 27 at White Sands Missile Range in New Mexico, a laser weapon on an Apache helicopter shot down an unmanned target during a collaborative test run by Raytheon Co., U.S. Special Operations Command (USSOCOM) and the Army’s Apache Program Management Office. The kilowattage of the laser used wasn’t released, but this test was news for several reasons.

For one, the dust stirred up by a helicopter’s rotating blades makes it harder for laser beams to hit targets. Hitting a target from a moving platform is difficult, and a moving platform that also vibrates, as an attack helicopter in flight does, adds another level of difficulty, since a laser beam needs to be held steady on the target for seconds. (How long exactly depends on the kilowattage of the laser beam.) Clearly, technical progress has been made.

Research efforts also focus on increasing the kilowattage and ability to control the beam of directed energy so as to hit not just cheap quadcopters but also aircraft, cruise missiles, armored targets and, someday, ballistic missiles (tricky, since ballistic missiles bear a heat-resistant coating to prevent them from burning up when they re-enter the atmosphere).

What’s coming in 2018? Lasers on big vehicles, lasers on medium-sized vehicles and presumably more lasers on helicopters, for the Army. In FY18, the High-Energy Laser Mobile Test Truck, a converted 34-foot-long Heavy Expanded Mobility Tactical Truck/cargo truck, should have a 50-kilowatt laser aboard and ready for demonstrations. By the end of FY17, the Army expects to select a contractor to mount a 100-kilowatt laser weapon on a more mobile vehicle like a Stryker or Bradley—a request from Soldiers in the field—for testing by 2022. The Air Force and USSOCOM plan to test a directed-energy weapon mounted on an AC-130 gunship by the end of the year.

By 2020, General Dynamics Land Systems, which builds the Stryker vehicle, expects to be able to fire a 30-kilowatt laser from a Stryker. Considering that 30 kilowatts currently requires a 570-foot-long ship with four electrical power generators to support, that’s quite an advancement. Leaps in capability don’t just happen, though; they take decades of research and development.

TOASTED
Adam Aberle, High Energy Laser Mobile Demonstrator program manager, U.S. Army’s Space and Missile Defense Command and Army Forces Strategic Command Technical Center, holds up a unmanned aerial vehicle displaying the damage caused by a compact laser weapons system during the during the Maneuver Fires Integrated Experiment, at Fort Sill April 21.(photo by Monica K. Guthrie)

CONCLUSION
Money spent in the 1970s now looks likely to pay off in the 2020s, in terms of a product in the field. Research conducted with the massed forces of the Soviet army in mind now looks like it will be most useful, at least in the short term, against cheap, low-flying drones, often flown by nonstate actors.

A ready force requires an acquisition and technology community capable of responding to “we need it now” requests like the mine-resistant, ambush-protected vehicle and the up-armored High Mobility Multipurpose Wheeled Vehicle, while sustaining much longer-term thinking. The lesson is one most observers of the defense scene already know: It can take a long time and some expensive failures to move from promising idea to program of record, from a technically possible capability to a tool in the warfighter’s hands.

For a historical tour of Army AL&T over the past 57 years, go to the Army AL&T archives at https://asc.army.mil/web/magazine/alt-magazine-archive/.

This article will be published in the October-December 2017 issue of Army AL&T Magazine.