World's Most Powerful Rail Gun Delivered to US Navy

An anonymous reader writes "The world's most powerful functional rail gun capable of accelerating projectiles up to Mach 8 has been delivered to the Navy. The new rail gun is a 32-megajoule Electro-Magnetic Laboratory Rail Gun. The Navy eventually hopes to have 64-megajoule ship mounted rail guns. 'The lab version doesn't look particularly menacing -- more like a long, belt-fed airport screening device than like a futuristic cannon -- but the system will fire rounds at up to Mach 8, drawing on tremendous amounts of electricity to generate the current for each test shot. That, of course, is the problem with rail guns: Like lasers, they're out of step with modern-day generators and capacitors. Eight and 9-megajoule rail guns have been fired before, but providing 3 million amps of power per shot has been a limitation.'"

Comments

Re:How silly

[paganizer]

I'm vaguely remembering a conversation I had when I was in the Navy, but from what I remember, the USS Enterprise was over engineered to have 8 reactors when they knew only 4-6 were really necessary because they had some thoughts of mounting energy weapons. since the Enterprise was drawn up in the late 50's I'm not sure whether to doubt it or not.

Space Gun

[Doc Ruby]

Mach 8 is about 9800KPH. Escape velocity from the Earth's surface is 40,320KPH. This gun is already firing at over 24% of escape velocity. A 64Mj gun would be almost 50%; a 132Mj gun would shoot projectiles right into orbit.

I wonder whether coming generations of this gun could shoot unmanned exploration vehicles or satellites out into space. The Pentagon will probably try to use it just to shoot down spacecraft, but instead we could use their budgets to increase space industry and exploration.

Looks nice

[OeLeWaPpErKe]

I wonder how many times this thing can be fired. They need to get 32 megajoules of energy out of the gun, and without the metal that this power passes through melting. That's not an easy thing to do.

Railguns today tend to melt after each shot, leaving one to replace the rails (the biggest, conducting the part of the gun, the bit in contact with the "bullet").

I wonder what the efficiency is. 32 megajoules come in, how many leave in the bullet. (Generally they only get about 2%-5% efficiency).

An alternative, easier and safer, is a coil gun. Here's a nice index of coilguns : World's coilgun arsenal. But like their railgun brothers, they're not very efficient. The very best of them have the bullet speed of a mini handgun, but they're trivial to make, and rely only on batteries and metal.

Re:How silly

[AKAImBatman]

The Enterprise was the prototype. Plus, Nimtz carriers only have 2 reactors. So it wouldn't surprise me if they overengineered her power supply for the intent purpose of mounting experimental weapons.

That being said, the Nimtz reactors are a bit more advanced than the Enterprise (lessons learned and all that), so that has a lot to do with the reduction in the number of reactors.

Everything beyond that is classified. I could tell you, but then I'd have to shoot you. (Assuming that I already knew and therefore had been shot. :P)

Re:uh, wrong. please check your math.

[AKAImBatman]

The DDX Destroyer is just the first step in the Navy's futurization of the fleet. The CVNX project intends to modernize carriers in the same way that the DDX Destroyers will be modernized.

Some of the features:

• Better, more powerful reactors (3x increase in available power!)
  
• Stealth
  
• Electromagnetic catapults
  
• Greater automation leading to reduced crew complement
  
• Better survivability in a fight (like that's been a big concern :P)
  
• Advanced arresting gear (no idea what that means)
  
• Dual Band Radar support
  
• "Flexible ship infrastructure" (i.e. We can mount some kewl energy weapons once Congress gives us the green.)
  

Navy Fact File

As I recall, the original list of superweapons was much more impressive. It just got pared back a smidge when Congress balked at the price tag.

Interesting Facts

[timias1]

I sat next to one of the directors of the Navy's rail gun program, during a flight to Boston, and I had one of the most interesting talks with him. The projectiles fired experience about 30,000 g's of acceleration, compared with 12,000 g's for a conventional gun. The major problem is that about 20% of the g's are experienced laterally because the projectile bounce when it is traveling down the rails. The projectiles do not contain explosives, because the kinetic energy is enough to do some pretty good damage. The materials problem with the rails was solved a while ago, and they need to survive for about 1000 shots to be comparable to today's guns. They also don't store the energy for very long before firing, because of losses and safety.