Slashdot Mirror
Navy Debuts New Railgun That Launches Shells at Mach 7
Jeremiah Cornelius writes: "The U.S. Navy's new railgun technology, developed by General Atomics, uses the Lorentz force in a type of linear, electric motor to hurl a 23-pound projectile at speeds exceeding Mach 7 — in excess of 5,000 mph. The weapon has a range of 100 miles and doesn't require explosive warheads. 'The electromagnetic railgun represents an incredible new offensive capability for the U.S. Navy,' says Rear Adm. Bryant Fuller, the Navy's chief engineer. 'This capability will allow us to effectively counter a wide range of threats at a relatively low cost, while keeping our ships and sailors safer by removing the need to carry as many high-explosive weapons.' Sea trials begin aboard an experimental Navy catamaran, the USNS Millinocket, in 2016."
...but at least part of the future is here already.
"Our opponent is an alien starship packed with atomic bombs," I said. "we have a protractor"
...Can someone who is explain where the big fiery explosion out of the railgun is coming from, if this thing is electromagnetically driven?
In Soviet Russia, Chuck Norris will still kick your ass.
Can it be efficiently powered, though? It always seemed like the power draw was the main issue with these kinds of guns, effectively limiting them to a few shots.
It's a "Small-waterplane-area twin hull" or SWATH, not a catamaran. http://en.wikipedia.org/wiki/S...
-73, de n1ywb
www.n1ywb.com
Railgun $25,000 a round versus $1,000,000 a round for missiles.
Cost on just purely physics level, is rather irrelevant. It is economics that are the limiting factor.
At last the US Navy, for so long the joke of the high seas, will become a force to be reckoned with.
how many pairs of boxer shorts should you own?
Well, judging form the pictures, this is the one disposable razor I wouldn't want to be shaved with.
Ezekiel 23:20
The railgun might fit, but where are you going to put the nuclear reactor to power it?
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Not to nitpick (well.....yah, I'm nitpicking), but both General Atomics and BAE Systems Railguns will be tested on the USNS Millinocket. BAE Systems actually got the Phase II contract, whereas General Atomics did not.
Link: http://breakingdefense.com/2014/04/navys-magnetic-super-gun-to-make-mach-7-shots-at-sea-in-2016-adm-greenert/
Full Disclosure: I nearly got to work on the GA RailGun system and I know some people who are on it. It's a better design than the BAE one but BAE got the contract.
Actually, do we know that there's any burning going on at all? I believe the light from a fire is not directly emitted by the chemical reaction, it's a result of the combustion gasses glowing from the heat. In which case just heating even an inert gas sufficiently will cause it to glow similarly. And the immense high-speed compression from a mach-7 projectile traveling down a confined tube should generate plenty of heat.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
So we're back to throwing rocks.
We just throw them very, very fast. :)
I do not fail; I succeed at finding out what does not work.
Perhaps one of the big benefits of a naval railgun is that it's so difficult to defend against. Old-fashioned anti-ship missiles can be disabled or destroyed by the defending ship's close-in defenses. This is because the incoming missile is filled with sensitive electronics, guidance systems, explosives, fuel, turbojet engines, stabilizing fins, etc, and is very likely to be damaged or destroyed if hit by a 20mm round from the defending ship's CIWS missile defenses.
However, how do you shoot down a hunk of metal traveling at mach 7 toward your ship? It wouldn't make any difference if you hit it with a 20mm round from the goalkeeper or phalanx. The projectile would just keep flying toward the ship and strike it anyways. Besides, how would you even hit something which is so small and traveling at mach 7.
It doesn't seem there would be any good defense against this.
I suspect it's compression rather than friction doing most of the heating. Much like an orbital reentry vehicle - the gas within the shockwave starts to glow long before it contacts the vehicle itself.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Many!
Imagine if you didn't need to handle explosives like Cordite as propellents anymore. This will reduce storage space and make a battleship's gun turret a while lot safer place to work. One small spark won't set off a magazine anymore.
"Muzzle velocity" is higher, so the distance you can throw something is a bit further, like 5x further. If you can fire further, you have a huge advantage because you can hit your opponent before he can shoot at you. Or if you are doing ground support, you can fire further inland.
I'm assuming a rail gun will be faster to reload. Might take some time to recharge the power supply, but surely we can fire faster than a Mark 7's 2 rounds a minute. More pounds and rounds on the target than your opponent is always better.
Finally, it may be possible to more strictly control forces on the shell when firing it, which may make it possible to put more technology IN the shells, and still get very high velocity. Imagine a shell that can adjust it's flight path, even slightly, which means you can fire in the general direction you want, then fine tune the aim in flight. (I assume they don't do that now..)
Issues to watch out for: First, Rail guns tend to have tracks (rails) and said rails usually have difficulty with wear due to the huge forces and high speeds involved. Hopefully they have engineered the better materials. Second, power supplies for rail guns have to be designed to provide HUGE impulse powers with power generation systems wanting to be running at steady state. You have to match the two. Finally, weapons like this usually mean you have to redesign the whole weapons system, a process that literally takes decades.
Go Navy, this is worth the R&D money..
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
according to the experts at yahoo answers, there isn't recoil in the traditional sense, but there is recoil because physics and also it somehow forms babby.
F=MA. M = big, A = very fast, therefore F = big very fast!
So, teaching in current mathematics has come to this?
We're doomed.
Faster! Faster! Faster would be better!
It's got a ways to go.
Tolerances causes more cost than you think, and documentation around military contract is generally at least half the cost of anything. It's not the contractors taking the piss (what, are you in OZ or UK?), but the government being stupid in supporting the military industrial complex.
Learn to love Alaska
Why the hell does an inert slug encased in a discarding sabot cost twenty grand?
The only way these get cheap is if we have to make a lot of them to fight a war. Be thankful we only have to deal with low-rate peacetime economics where the development costs of unique tooling gets amortized across a small number of prototype rail gun slugs creating a big per-unit price tag that causes fools to go apoplectic.
Maw! Fire up the karma burner!
Smaller diameter projectiles have more drag per unit mass and slow down faster due to air resistance. It's called their ballistic coefficient.
The practice for howitzer-like weapons like railguns is to fire their projectiles in a high arc to get them out of thick atmosphere as fast as possible to reduce air friction. They still won't hit their target at anything like their muzzle velocity even after they recover some kinetic energy on the way back down to target from the top of their parabolic arc.
The ballistically efficient shells from the late-model 15" US Naval rifles had a muzzle velocity of about 3500 feet/second and a flight time to target at maximum range (25 miles or so) of a couple of minutes. Their velocity at impact was half that of their muzzle velocity. I don't see these railgun projectiles achieving anything like that performance as drag increases roughly as the square of velocity and their ballistic coefficient will be a lot less.
The navy will secretly transport it to the moon, there the speed will be enough.
Yes, but who're you going to crew it with, convicts? They'll just build another one and throw rocks at us.
You're special forces then? That's great! I just love your olympics!
The future is never now..the present is now.
The Kruger Dunning explains most post on
Now is always the past. Your perception is delayed, unless you are the event.
Finally had enough. Come see us over at https://soylentnews.org/
Too soon.