Rail gun uses kinetic energy to deliver Mach 5 wallop
(Credit:
U.S. Navy)
The U.S. Navy is installing an electro-magnetic laboratory rail gun at its Surface Warfare Center in Dahlgren, Va., bringing it one step closer to developing a ship-mounted version of this futuristic cannon.
The 32-megajoule weapon appears to be the largest rail gun ever built, according to defense contractor BAE Systems. A joule is what's needed to produce one watt of energy for one second.
It uses a magnetic "rail" instead of a chemical propellant like gunpowder to heave projectiles at Mach 7 for what could be up to 220 miles down range--that's 10 times farther than what contemporary naval guns. The projectile hits at Mach 5, destroying the target with kinetic energy instead of conventional explosives.
Ship building and design are expected to benefit should the new gun prove feasible, mainly because new vessels won't be forced to haul tons of explosives. But while the rail gun uses no gunpowder, it can hardly be called energy efficient. A planned 64-megajoule system would suck around 6 million amps.
In addition to developing new onboard capacitors or pulsed alternators to power the weapon, the Navy must come up with new materials to secure the gun, firing it can dislodge the conducting rails--or even rip the gun barrel apart, according to some reports. The Navy, which has already tested smaller versions, as seen in the video, wants a rail gun onboard a ship as early as 2020.
Mark Rutherford is a West Coast-based freelance writer. He is a member of the CNET Blog Network, and is not an employee of CNET. Email him at markr@milapp.com. Disclosure. 
Like launching people into space! :)~
Gotta feel the acceleration!
Seriously, this is stupid. This has an extremely high of an energy requirement to make this practical. Have they forgotten about rockets?
This is government waste at is worst.
Ever serve on a naval vessel?
Well I have.
Eliminating the need for highly complex, highly dangerous, highly expensive (and highly combustible!) systems for the development, maintenance and deployment of chemical rocket motors is a GOOD thing.
Last thing- About the energy requirements?
Naval combat vessels aren't Hyundai Sonata's.
They're very big, and they can carry turbine generators up the wazzoo.
Can a ship currently produce enough power for all its systems, plus this?
No!
What that means is more nuclear reactors are needed. A terrible idea for little to no gain.
The ship will still have to carry weapons loaded with HE.
It is a bad and wasteful idea.
In 2004, a Navy technology assessment estimated the power for a rail gun could be supplied by a 15 to 30 MW dedicated pulsed alternator power generator. Other solutions use capacitors and excess power from existing on-board gas turbine generators.
As a comparison, a conventional high-explosive round uses 90 lbs of explosive propellant with a high-explosive warhead that weighs 260 lbs. The energy needed for a non-explosive 44-lb rail gun round is generated by 3 gallons of fuel.
The Navy is currently installing MKII Mr Fusions aboard all its vessels.
;-)
A Joule is a unit of energy, A Watt is a unit of power. 1 Watt of power delivers 1 Joule of energy each second.
1st of all, I've read (and reread) the article and don't see a mention of supporting "ground based operations" anywhere in it.
A system like this would, however, provide excellent protection against what current naval missile systems are currently designed to do- Namely, knocking incoming aircraft out of the skies.
2nd of all, in the system WERE to be deployed as "ground cover", how in the blue blazes would the EXCLUSION of HIGH EXPLOSIVES, contribute to "damaging everything except the target"?
Logically, it should be evident to even the most casual of reader, that by ELIMINATING THE EXPLOSIVE WARHEAD, you can't damage everything EXCEPT the target.
Need I continue?
A projective with no self-propelled ability is going to shoot down aircraft at 100+ miles?
If you understood what a rail gun is, you would know it is a terrible idea.
It is get a million to one shot off, or die.
Nice weapon.
Also, and unlike the ECM susceptible missile, a soup can sized projectile won't show up on radar.
"The Marines, in particular, are interested in the potential for rail guns to deliver supporting fire from up to 220 miles away -- around 10 times further than standard ship-mounted cannons -- with rounds landing more quickly and with less advance warning than a volley of Tomahawk cruise missiles."
My understanding is that they shoot the projectiles in an arc. For reference purposes, Tomahawk cruise missiles travel at about Mach 0.9. Russia and India have jointly developed a cruise missile that can go Mach 2.8 and has a 200-mile range. India is talking about a Mach 8 cruise missile. See http://en.wikipedia.org/wiki/Brahmos
But the rail guns might have big advantages in fire rate, number of rounds, and cost per shot.
Maybe they should have tried a smaller trial concept. Maybe something around the scale & purpose of a replacement for the Phalanx ADA system. The power requirements would have been less than a full sized gun/launcher for the same rate of fire as the modified Vulcan & much easier to test to prove the concept.