Electromagnetic Railgun

Electromagnetic Railgun | Popular Science

Picture this: A massive destroyer receives the location coordinates of an enemy headquarters more than 200 miles away. Instead of launching a million-dollar Tomahawk cruise missile, it points a gun barrel in the direction of the target, diverts electric power from the ship’s engine to the gun turret, and launches a 3-foot-long, 40-pound projectile up a set of superconducting rails. The projectile leaves the barrel at hypersonic velocity—Mach 7-plus—exits the Earth’s atmosphere, re-enters under satellite guidance, and lands on the building less than six minutes later; its incredible velocity vaporizes the target with kinetic energy alone.

Railgun - Wikipedia, the free encyclopedia

A railgun is an entirely electrical gun that accelerates a conductive projectile along a pair of metal rails using the same principles as the homopolar motor. Railguns use two sliding or rolling contacts[1] that permit a large electric current to pass through the projectile. This current interacts with the strong magnetic fields generated by the rails and this accelerates the projectile.


Railguns are being researched as weapons with projectiles that do not contain explosives, but are given extremely high velocities: 3,500 m/s (11,500 ft/s, approximately Mach 10 at sea level) or more (for comparison, the M16 rifle has a muzzle speed of 930 m/s, or 3,050 ft/s), which would make their kinetic energy equal or superior to the energy yield of an explosive-filled shell of greater mass. 

The Office of Naval Research (ONR) achieved a world record Dec. 10 when it successfully conducted a 33-megajoule shot of the Electromagnetic Railgun at Naval Surface Warfare Center Dahlgren Division. Chief of Naval Research Rear Adm. Nevin Carr offered these remarks:

"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," Carr said. "The high velocities achievable are tactically relevant for air and missile defense. This demonstration moves us one day closer to getting this advanced capability to sea.”