An artist's rendering of a neutral particle beam.

An artist's rendering of a neutral particle beam. IMXPIX Images

Pentagon Shelves Neutral Particle Beam Research

One of the U.S. military’s most ambitious space-based projects has crashed back to Earth.

Defense officials are taking a step back from one of its most ambitious research goals: launching a massive neutral-particle-beam generator, essentially a ray gun, into space to fry the electronics of enemy missiles. The funds will go instead toward more fundamental research aimed at making lasers more powerful, according to Michael Griffin, defense undersecretary for research and engineering.

It marks a return to Earth for one of the biggest ideas that the Department has broached in recent years. Griffin first publicly floated the idea of a neutral particle beam in space in March 2018, while highlighting potential directed-energy weapons beyond high-powered lasers. 

“High-powered microwave approaches can affect an electronics kill. The same with the neutral particle beam systems we explored briefly in the 1990s,” he said.

In March, Defense and military officials announced their intention to test a neutral particle beam in space in 2023, and requested $34 million to develop it in the 2020 budget. 

Congressional Democrats weren’t pleased. In May, the House Appropriations Committee stripped the beam’s funding from their version of the defense authorization bill. 

Kingston Reif, who leads disarmament and threat reduction policy at the Arms Control Association, summed up the view of the project’s detractors. “Congress made it clear it wouldn't fund the project, so the writing was on the wall. But this begs the question of why Griffin included $34 million for the gambit in the FY 2020 budget request — and $380 million over the next five years — in the first place. Space-based interceptors, whether kinetic or non-kinetic, would be costly and massively destabilizing. The costs and risks vastly outweigh any potential benefits,” Reif told Defense One in an email. 

On Wednesday, Griffin acknowledged the hard truth. “We are deferring work on neutral particle beams, indefinitely,” he said at the Defense News conference in Virginia. “It’s just not near-term enough.”

But Griffin added that the Pentagon is still pursuing directed energy research in lasers and microwave energy, aiming eventually to deploy them on combat aircraft, with ground units, and aboard satellites.. 

“My own opinion is we need to get systems built and put onto platforms so we can see what they do how they do it,” he said, meaning how the weapons interact with their platform(s) and environment. “We need to understand the lethality of those systems, things like beam control. We need to know how to scale them up in practical ways. If you have 250 kilowatts of, say, laser, and you are operating at best at 50-percent efficiency, you have to figure out what to do with the other kilowatts of heat. 

“So there are a lot of practical problems with real-world weapons systems,” he said. “We are spending money on it.”