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Laser Weapon to Go in Fighter Jet in 2021

Lockheed will tackle the next big challenge in laser weapons—putting one in a top-gun fighter jet

2 min read
Illustration showing a tactical fighter jet with a high energy laser weapon system blasting something in the distance.
Illustration: Air Force Research Lab

Nothing says futuristic 'top gun' like a fighter jet using a high-energy laser to blast enemy missiles out of the sky. That future may be only a few years away. The Air Force Research Laboratory (AFRL) has issued a $26.3-million contract to Lockheed Martin to design, develop, and build a high-energy laser for tests in a tactical fighter jet by 2021. The key technology is an advanced version of a multi-kilowatt fiber laser like the one the Navy tested earlier on the USS Ponce.

Fiber lasers started as a dark horse in the development of electrically-powered laser weapons that culminated in a demonstration of a 100-kilowatt laboratory laser by Northrop-Grumman in 2009. Multi-kilowatt fiber lasers were already in use in industrial machining, but conventional wisdom said that fiber laser output was limited because optical power was concentrated inside the fiber's tiny light-guiding core. Though that setup maximized how efficiently a fiber laser could convert electrical energy into light and gave good beam quality, it also raised the power density so high that a single fiber couldn't emit much more than about 10 kilowatts without self-destructing.

At the time, it seemed impractical to combine beams from many fiber lasers; in doing so, you’d  sacrifice the beam quality needed to focus power on distant targets. What changed the picture was the development of a high-power version of the wavelength-division multiplexing (WDM) technique used in high-capacity fiber-optic telecommunications. At low power, WDM can merge the outputs of 100 different lasers, each operating in its own narrow slice of the spectrum, into a single fiber core without causing interference. Lockheed has extended what it calls “spectral beam combining” to high-power fiber lasers, starting with a 30-kW system that combines light from about 100 lasers and uses less than half the power of other electric lasers. This year, Lockheed delivered a 60-kilowatt version to the Army for testing in a military tractor-trailer.

The AFRL contract is part of its Self-protect High Energy Laser Demonstrator, or SHiELD, program The aim is to test capabilities of a fighter jet that uses lasers to defend itself against missiles launched from the air or ground. Separately, Northrop-Grumman is building a beam control system to fire at targets, and Boeing is integrating the laser into an external pod that will contain it in flight, power it, cool it, and coordinate its actions with the aircraft’s systems.

Meanwhile AFRL and DARPA are also planning airborne tests of a competing, non-fiber laser system. The compact and lightweight electric laser, called HELLADS, was developed by General Atomics.

Cost has long been an issue with laser weapons, but fiber lasers should be affordable because they leverage a very large technology base for fiber-optic communications and industrial lasers, says Rob Afzal, senior fellow of laser weapon systems at Lockheed. “We have to manage weight both for what the pod can accept and for things like the center of gravity,” says Afzal. But he adds, “fitting it into a tight, compact space is the bigger challenge,” as well as ruggedizing the laser to withstand the vibration, temperatures, and G forces encountered in a tactical aircraft.”

The Conversation (0)

Economics Drives Ray-Gun Resurgence

Laser weapons, cheaper by the shot, should work well against drones and cruise missiles

4 min read
In an artist’s rendering, a truck is shown with five sets of wheels—two sets for the cab, the rest for the trailer—and a box on the top of the trailer, from which a red ray is projected on an angle, upward, ending in the silhouette of an airplane, which is being destroyed

Lockheed Martin's laser packs up to 300 kilowatts—enough to fry a drone or a plane.

Lockheed Martin

The technical challenge of missile defense has been compared with that of hitting a bullet with a bullet. Then there is the still tougher economic challenge of using an expensive interceptor to kill a cheaper target—like hitting a lead bullet with a golden one.

Maybe trouble and money could be saved by shooting down such targets with a laser. Once the system was designed, built, and paid for, the cost per shot would be low. Such considerations led planners at the Pentagon to seek a solution from Lockheed Martin, which has just delivered a 300-kilowatt laser to the U.S. Army. The new weapon combines the output of a large bundle of fiber lasers of varying frequencies to form a single beam of white light. This laser has been undergoing tests in the lab, and it should see its first field trials sometime in 2023. General Atomics, a military contractor in San Diego, is also developing a laser of this power for the Army based on what’s known as the distributed-gain design, which has a single aperture.

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