There is no one to shoot.
There doesn't need to be anyone to shoot - it is there to prevent those who attempt to be something to be shot at. Remember, it took one bomb to end WWII.
Two bombs.
Navy tests rail gun
101–106 of 106 posts
Re: Navy tests rail gun
#102Would this type of weapon be able to shoot satellites right out of the sky?
It doesn't take much power to shoot a satellite out of the sky. The hard part is actually hitting it.
Let's say you're aiming at a GPS satellite in geostationary orbit. According to Wikipedia (http://en.wikipedia.org/wiki/Geostationary_orbit) you're trying to hit a target that is 20,000 miles up in the sky moving at about mach 10, and the target is the size of a car. We don't have the tech for that kind of dumb-fire accuracy, even if you fire the gun from above the atmosphere. At 20,000 miles, you would need to reliably place a shot within slightly less than 1/1000th of an arcsecond.
In order to hit a target under those conditions, you would need a projectile that can do course corrections on the way to the target. Like a missile.
Re: Navy tests rail gun
#103Interestingly this story makes me wonder whether economic consequences even enter the picture when choosing to engage. I never would have imagined an admiral asking themselves "Is this worth the cost of a $1.5 million missile?" I reckon that it would be a binary decision based on threat alone. Are there any guidelines in the military where the commanding officer is instructed to perform any sort of cost benefits analysis when making the decision to engage a hostile?
Would a dramatically lowered cost greatly increase the likelihood that the navy will be more willing to act as an aggressor?
Re: Navy tests rail gun
#104Earlier quoted context omitted.
Why couldn't there be small metallic wheels in the barrel making contact with the projectile? Wouldn't that prevent wear?
I imagine you could do something like this. Off the top of my head this would pose a few issues. 1) While the magnetic force must go from one rail to the other, the amount of electric force is effected by how much of the body is doing the conducting(if my memory servers me). So while you could use wheels, you would still want the current to flow through the entire(or large portion) of the projectile housing(for lack…
Many wheels, possibly in the form of many small ball bearings on a rail should work. Many small cylinders instead of spherical bearings would be better.
Even better would be a highly conductive grease non-flammable grease.
Re: Navy tests rail gun
#105Earlier quoted context omitted.
I imagine you could do something like this. Off the top of my head this would pose a few issues. 1) While the magnetic force must go from one rail to the other, the amount of electric force is effected by how much of the body is doing the conducting(if my memory servers me). So while you could use wheels, you would still want the current to flow through the entire(or large portion) of the projectile housing(for lack…
Many wheels, possibly in the form of many small ball bearings on a rail should work. Many small cylinders instead of spherical bearings would be better. Even better would be a highly conductive grease non-flammable grease.
The bearing idea isn't a solution for a few reasons:
1) Rotating bearings still have internal friction, which will still generate tremendous heat at these velocities.
2) A lot of the heat being generated here is caused by the flow of electrical current, which isn't negated by bearings. In fact, it would probably be made worse, because any spherical contact patch is going to be tiny compared to a flat surface. The suggestion of using many small bearings would seem to alleviate this problem, but the smaller you make the bearing, the more fragile it becomes.
At its heart, this is a materials science problem. You need a material that can conduct the electricity, withstand the heat, and not break down under high friction loads while doing both of these. Simply dropping in a bearing doesn't solve any of these problems
The highly conductive, non-flammable grease is just another materials challenge. At the kinds of temperatures present in a rail gun, "non-flammable" becomes a very high bar for a lubricating fluid.
Re: Navy tests rail gun
#106Earlier quoted context omitted.
They're great against a low-tech adversary, but against serious ballistic or (some) cruise missiles, they're just slowly-moving seaborne apartment blocks. Good writeup here: http://exiledonline.com/the-war-nerd-this-is-how-the-carrier...
This is really informative. You should submit it.
https://news.ycombinator.com/item?id=547596 - should probably have searched before posting original link :)