The Office of Naval Research (ONR) achieved a milestone Dec. 10 when it successfully conducted a world-record 33 megajoule shot of the Electromagnetic Railgun at Naval Surface Warfare Center Dahlgren Division. In 2008, ONR conducted a 10-megajoule shot for media and visitors at Dahlgren. Friday’s demonstration showed researchers are steadily progressing toward developing a gun that could hit targets almost 20 times farther than conventional ship combat systems. A 33-megajoule shot, for example, could potentially reach extended ranges with Mach 5 velocity, five times the speed of sound.

The Electromagnetic Railgun is a long-range, high-energy gun launch system. It uses electricity rather than gun powder or rocket motors to
launch projectiles. Its projectiles strike at more than 200 nautical miles in approximately six minutes. Electricity generated by the ship is stored over several seconds in the pulsed power system. Next, an electric pulse is sent to the railgun, creating an electromagnetic force accelerating the projectile to Mach 7.5. The kinetic energy warhead eliminates the hazards of high explosives in the ship and unexploded ordnance on the battlefield.

“Today’s Railgun test demonstrates the tactical relevance of this technology, which could one day complement traditional surface ship combat systems,” said Rear Adm. Nevin Carr, chief of naval research.

“The 33-megajoule shot means the Navy can fire projectiles at least 110 nautical miles, placing Sailors and Marines at a safe standoff distance and out of harm’s way, and the high velocities achievable are tactically relevant for air and missile defense,” he added. “This demonstration moves us one day closer to getting this advanced capability to sea.”

The Electromagnetic Railgun INP was initiated in 2005. The goal during phase I is a proof-of-concept demonstration at 32 mega-joule muzzle energy. This is about half the energy required for a fully capable 200-plus nautical mile system and would be capable of launching a 100-nautical mile projectile. This launch energy has the advantage of being able to stress many components to evaluate full-scale mechanical and electromagnetic forces.

Phase I is focused on the development of launcher technology with adequate service life, development of reliable pulsed power technology and component risk reduction for the projectile.

A second phase INP, proposed to start in 2012, will advance the technology for transition to an acquisition program. Phase II technology efforts will increase launcher muzzle energy and concentrate on rep-rate fire capability. Thermal management techniques required for sustained firing rates will be developed for both the launcher system and the pulsed power system.