From the
Military Times:
Navy breaks record with railgun test-shot
DAHLGREN, VA. — The Navy set a new world record for the most powerful electromagnetic railgun when it fired a test shot here Thursday morning.
The gun fired an aluminum projectile at 10.68 megajoules. A joule is the work needed to produce one watt of energy for one second. A megajoule is 1 million joules.
Watch video of the test
Guests including Chief of Naval Operations Adm. Gary Roughead and Rear Adm. William Landay, head of the Office of Naval Research, witnessed the shot via a live video feed at the Naval Surface Warfare Center in Dahlgren. The gun was launched from a control center after approximately four minutes of charging the electromagnetic rails. After the charge, the gun fired and witnesses saw a quick burst of flame as the projectile, traveling at 2,500 meters per second, or Mach 7, hit its target.
What does Mach 7 mean? For this discussion, mach is the speed of sound at sea level at a temperature of 15 degrees celsius which is 761.2 mph or 1115 feet per second.
To bring some perspsctive, 2500 meters/second is 1.553 miles per second or 5,591 mph. That is 8200 feet per second. Compare that to a high powered rifle at 3200-3600 f/s. Most jet fighters have a speed limit below Mach 2. Escape velocity from the earth's gravitational field is about 6.95 miles per second (25,000 mph) or 11,200 meters per second.
Roughead called the gun a “revolutionary approach to naval warfare.” He acknowledged the Navy is “a ways from seeing this in the fleet,” but said it is important that the service “never loses sight of the next big thing.”
The previous railgun record of 9 megajoules was held by the Center for Electromagnetic Materials and Devices at the University of Texas, according to the Office of Naval Research. The Institute for Advanced Technology, also at the university, certifies electromagnetic railgun launches.
An EM railgun is powered by electricity rather than gunpowder. A shell is launched at Mach 7 through the electromagnetic rails into the atmosphere for about one minute, flies out of the atmosphere for four minutes, and then descends to Earth toward its target at Mach 5 in approximately one minute. The projectile is guided using the Global Positioning System.
This is so cool. I wonder if they will ever come out with a hand held version?
The Navy hopes an EM railgun onboard a ship could increase ship design options because the gun weighs less and requires less infrastructure than traditional guns that use gunpowder and magazines.
Traditional fire-protection and ammunition-handling requirements are not necessary using an electromagnetic-pulse power system. Potentially, this could change the way the service thinks about naval gunnery, Landay, the head of ONR, told reporters after the test firing.
The Navy plans to have an EM railgun onboard a ship, potentially its next-generation cruiser CG(X), between 2020 and 2025. Officials declined to say what ship would be a good candidate for the gun.
“The gun can fit on any electric ship,” said Elizabeth D’Andrea, the EM railgun program manager at ONR.
