RIP Railgun: Why the U.S. Navy's Super Weapon Might Be Dead
In the year since publishing the jaw-dropping footage of a tactical electromagnetic railgun demonstrator at the Naval Surface Warfare Center, Dahlgren Division’s Terminal Range in Virginia in November 2016, ONR has been working diligently alongside defense contractors BAE System and General Atomics to bring the supergun closer to combat readiness. A second video released in July showed the rig firing off multi-shot salvos on Dahlgren’s 25-mile Potomac River test range. Through massive, repeated pulses of energy over a short period with minimal cooldown time, the railgun managed to fire 4.8 shells a minute, inching closer to the requirements laid out by Naval Sea Systems Command in a 2013 call for demonstrators that could fire 10 shells a minute and store up to 650 shells.
While ONR’s rep-rate demonstrations at Dahlgren represent a major leap forward for the railgun, the system still faces major technical hurdles that make the HVP a relatively inexpensive alternative. Generating the electromagnetic fields necessary to accelerate a shell to tank-liquefying velocities without chemical propellants requires an energy farm or capacitor base significantly larger than what most Navy surface vessels can generate currently. Next-generation “electric warships” like the Zumwalt can channel 78 megawatts from their generators through its power-distribution network, making them ideal for all manner of directed-energy weapons, but other surface vessels would require a major overhaul of their electrical infrastructure for the “pulsed-power architecture” required for multi-shot salvos.
The crucial railgun component that may threaten the entire effort is the “common mount.” A universal system for equipping sea or land-based platforms with a mass-produced tactical electromagnetic railgun, a 2016 House Armed Services Committee report noted that lawmakers were increasingly worried that SCO’s newfound HVP fetish “[had] left the Navy with a funding gap in developing the requirements and design for a common mount, which is a necessary prerequisite to getting this capability into operational use.” No mount, no tactical demonstrations — and, in turn, no railgun.
Without actually mounting a working demonstrator on a surface vessel, sources say, the electromagnetic railgun could land in a “valley of death” between R&D and procurement that may prevent the ambitious, decade-long project from ever going to war. As with most technological moonshots, success and failure are a matter of optics: If the ONR can’t show off something with a Tony Stark-level “wow” factor for the military planners and lawmakers who pull ONR’s purse strings, researchers risk letting their political capital on Capitol Hill and in the Pentagon E-ring slip away.
“Promising technologies fall into the ‘valley of death’ all the time,” a legislative source told Task & Purpose. “Testing is great, but unless you want to put money into transitioning that tech into an actual weapons system then what the hell are you doing? We’re afraid to take a risk and try to get things moving.”
The railgun’s advocates know the supergun is in trouble. In July, Rep. Jim Langevin, a Democrat from Rhode Island and co-chair of the Congressional Directed Energy Caucus, recommended an additional $26.4 million SCO outlays in the House Armed Service Committee’s version of the 2018 defense budget explicitly earmarked as “transition funding” for a shipboard tactical railgun demonstrator program, the second legislative boost to the project alongside an additional $15 million added to the Innovative Naval Prototypes line item by the Senate, according to an amendment justification obtained by Task & Purpose. According to the Navy’s 2017 strategic program guide, the bulk of the appropriations already designated under that item line are for developing the thermal-management techniques that both the launcher and pulsed-power architecture require for that target sustained firing rate of 10 shells a minute.
The three-month continuing resolution passed in September offered a brief reprieve for advocates to make the case for an additional millions in transition funding to achieve a successful shipboard demonstration, and as of late November, lawmakers had authorized just $15 million of Langevin’s $26 million railgun amendment, funding the congressman told Task & Purpose would likely boost R&D efforts on the common mount.
“Our Navy must be given the ability to test this weapon’s lethality, range, and power at scale, and it must continue to develop the common mount prototype to take this technology to the next level for a shipboard demonstration,” Langevin told Task & Purpose.