Navy’s Magnetic Super Gun To Make Mach 7 Shots At Sea In 2016

[Savannahmann]

28. Seriously?

Applications, like shooting things into space. Let's do a little theoretical exercise shall we? Satalites are designed for launch by rockets. These are normally less than five G forces, or five times the gravitational constant.

Design something that can be launched out of a rail gun barrel with sufficient force to acheive orbit, or even break the gravitational field of earth. Now, you might get a "dumb slug" chunk of alloy to do it. Assuming that the deflection from the atmosphere didn't cause it to change course significantly enough to fail to achieve orbit. But let's pretend that the atmosphere isn't a problem.

The G-Forces would be up over that of an automobile accident. Short readings of 100 G's have been read, and survived, in specially equipped race cars. But the acceleration of a rail gun round towards space would be way more than that. Any electronics inside the bloody thing would be powder in the can of the round. If the electronics were designed to handle the what, thousand or so G's of acceleration, they would be so large and robust that there wouldn't be room in the round for more than a small chip that went beep ala Sputnik.

So perhaps we could target asteroids that were going to hit the earth. Again, atmospheric deflection, that darned thing that makes stars twinkle, would be an issue. The Keck observatory uses lasers to measure the atmospheric interference, and ajust the mirrors constantly, when taking images of faint objects. So your rail gun would have to pound out thousands of rounds before one managed to hit the asteroid in question. Each round monitored and measuring the atmospheric deflection, and then you would have more atmospheric defleection from the passing of the round at several times the speed of sound.

I read one book where the railguns fired from orbit. One meter rounds fired at a planet. They had a deflection of over a kilometer. In other words, from the point of aim, the round could miss by as much as a 1,000 meters. Sure if you fire enough rounds, you'll eventually pound everything in the region to dust.

But to be honest here, to have an effective asteroid interception system, it would have to be space based. Darn that treaty that prohibits such things. Then the platforms would have limited ammunition. I mean, there is no such thing as unlimited ammunition except in Hollywood.

So the idea of using a rail gun to shoot things into orbit is romantic nonsense at best. The idea of using it to intercept asteroids is questionable at best. That leaves what the Navy is doing, planning on using it to slaughter people. I mean, kinetic energy is one of the most misunderstood of all the energy forces. NASA forgot how much kinetic energy things moving fast can have, hence the Columbia foam strike problem. The instinctive response was it's foam, you don't destroy your car running over it on the highway. But as we learned, even foam traveling fast enough can do catastrophic damage to an object.

So the only real use for the Rail Gun is to launch Kinetic Kill Rounds. Chunks of alloy traveling rather fast to do catastrophic damage to people and buildings. Which is why they are not seeing how far the round can go, but are seeing what kinds of things it can go through.