Navy Rail Gun

Just weeks after the U.S. Navy trotted out images and a few short videos of its devastating electromagnetic “railgun”, (EM Railgun, blowing a fiery hole in a target at the Naval Surface Warfare Center in Dahlgren, Va., a new and longer video has begun to make the rounds (see below). Whereas previous testing had taken place in the lab, this video indicates the Navy has moved the technology one step closer to combat.

For the uninitiated, a railgun fires projectiles using electricity instead of chemical propellants. Magnetic fields created by strong electrical currents accelerate a sliding metal conductor between two rails to launch projectiles at about 7,200 to 9,000 kilometers per hour, compared to perhaps 5,400 kilometers per hour for a conventional gun. By equipping ships with railguns rather than standard artillery, the Navy could eliminate the hazards of having high explosives on board ships.

The Navy is evaluating two EM Railgun models. A 32-megajoule prototype built by BAE

Systems arrived at the Naval Surface Warfare Center the end of last month. (A megajoule of energy is equivalent to the kinetic energy of a 900-kilogram car moving at about 160 kilometers per hour.) General Atomics—best known as the maker of the Predator and Reaper drones—is building the second launcher, scheduled for delivery in April. The Navy says that the railgun project, initiated in 2005, will yield a 20- to 32-megajoule weapon that shoots a distance of 50 to 100 nautical miles (roughly 90 to 185 kilometers).

The Navy has contracted BAE and General Atomics to develop thermal management systems for both the launcher and pulsed power source  to increase firing rates  from a single shot to 10 rounds per minute.

U.S. Navy railgun photo by John F. Williams/Released
Video provided by the U.S. Navy

About the Author: Larry is the associate editor of technology for Scientific American, covering a variety of tech-related topics, including biotech, computers, military tech, nanotech and robots. Follow on Twitter @lggreenemeier.