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The US Navy Wants More Railguns and Lasers, Less Gunpowder
coondoggie writes Speaking before nearly 3,000 attendees at the Naval Future Force Science and Technology EXPO in Washington, D.C., Chief of Naval Operations Admiral Jonathan Greenert charged his audience to reduce reliance on gunpowder in a wide-ranging speech on the future technological needs of the Navy. "Number one, you've got to get us off gunpowder," said Greenert, noting that Office of Naval Research-supported weapon programs like Laser Weapon System (LaWS) and the electromagnetic railgun are vital to the future force. “Probably the biggest vulnerability of a ship is its magazine—because that’s where all the explosives are." Weapons like LaWS have a virtually unlimited magazine, only constrained by power and cooling capabilities aboard the vessel carrying them. In addition, Greenert noted the added safety for Sailors and Marines that will come from reducing dependency on gunpowder-based munitions.
How is that fancy laser going to work when the enemy uses a smoke screen? Or a mirror?
The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
However successive UK governments have seen "improving" the navy as meaning strip it of as many ships as it can. Soon it'll consist of 2 men and a rowing boat. Oh, and one overpriced aircraft carrier with no planes that can fly from it.
Yes they are, an aluminium slug impacting the ground at say Mach 15 does not need any gunpowder to create a large hole in the ground or destroy a building, the kinetic energy of the projectile will do that all by itself.
You do not understand diplomacy. It is not about winning it is about balance of power. A trade agreement which is favor of, lets say, the US and the other side must pay, then this will result sooner or later in less respect for the US. In the end they hate the US for being rude and brutal even without weapons. However, this is the diplomacy the US normally does. And often it is not only not in the interest of the other nation, it is also not in the interest of the general population in the US.
All would be much better when the US would be able to learn to be less imperial. And yes, the Chinese try to be the same. That will also not help to have stable world politics.
There's actually a few tradeoffs here. Unless it's a nuclear powered ship, then efficiency does matter. Fuel is much more energy dense, due to not having its own oxidiser, but railguns are fearfully inefficient. Unless they get the efficiency up then the fuel might take up more space. That said, being liquid, it fits into awkward spaces more easily.
As for power, that's an interesting one. If you look at the proposed railgun specs, the slugs have about the same kinetic energy as a WWII battleship round from at 16" gun. While the velocity of a railgun round is much higher, it doesn't weigh well over a ton. Plus, the battleship round also has about the same energy again as an explosive payload. So in practice the railgun will have about half the energy delivery capacity of a single round from a WWII battleship.
Of course, the railgun has a much longer range, a much higher speed, is much smaller and doesn't requite an unstable mix of fuel and oxidiser to be carried so that is a win.
In terms of armor, that's more or less gone from ships. The reason being that modern torpedos and some missiles which dive shortly before impact essentially make explode under the ship not against it, lifting it partly out of the water and creating a bubble which the ship falls into breaking its back. Armor is more or less worthless against that sort of attack. So if you're in a war with the USSR, there's no point in having any.
Excpet the only naval engagements from western nations in vaguely recent times have been things like the exocet missile strikes frmo the Falklands war (again less energy than a battleship round, and armor would have helped), a boat packed with explosives (again armor would have helped) and a few others. So ship armor is already more or less worthless against a modern well equipped navy, but it's probably worth having for when one isn't engaging one of those.
But back to the railgun.
There's an interesting thing that hitting a target with a high energy inert round often doesn't do a whole lot of damage. There was a case in WWII of some armed merchant cruisers (i.e. cargo ships with a couple of obsolete guns welded on) were mistaken for cruisers by some German raiders. The raiders engaged at long range with AP rounds and scored some direct hits. The AP rounds went all the way through the unarmored ships and out the other side without detonating (they were designed to penetrate a bit into armor and then detonate: the lack of armor caused the warhead to not trigger). The end result was that the ships wound up with some perfectly survivable 15" holes in them and managed to escape.
Likewise, the British army still like their HESH rounds, because the APFDS rounds (basically a long, thin very high speed slug designed to penetrate thick tank armour) have the annoying habit of going right through more lightly armoured vehicles without doing significant damage except for two small holes, where as the HESH rounds tear them open.
The cause of this is that very high energy rounds are hard to stop. Even the target has trouble stopping them, and if it fails to, then they leave with most of their energy and deliver it elsewhere.
In fact come to think of it, back when muskets were becoming obsolete, some armies found that although the modern high speed, high accuracy bullets made it much easier to hit the target, they tended to go right through people. The result being that again, the round not only had to hit a person but unlike a musket ball, had to hit something important, so there was a much higher survivability rate from people who were shot.
So, what I wonder is how the railguns fit into this. It seems that they'd be prone to very effectively making a couple of small holes in whatever they hit and delivering most of the energy into the sea or ground. Unless you actually hit the engines or some other critical piece, a ship, especially a warship can survive a surprisingly large number of holes before it is put out of action.
SJW n. One who posts facts.
I am sure he actually understood. He just wanted to take the chance to make an idiotic comment about the U.S. to what he hoped would be a receptive audience. I mean it takes a truly special person not to notice just how much the U.S. engages with all the other nations of the world.
Naval gun propellant charges now use LOVA propellants (originally developed for tank and SPA munitions). These are RDX, and later, HMX-based formulations. Nitrocellulose is old-school; it went out with the last battleships. I know. I worked at NSWCIH on the project. You fail current knowledge forever.
but railguns are fearfully inefficient.
Compared to chemical propellants? I don't think so.
Unless they get the efficiency up then the fuel might take up more space. That said, being liquid,
I'm fairly certain the nuclear reactor that powers the guns and the ship won't be that big of a problem. They don't do it on diesel.
Armor is more or less worthless against that sort of attack.
Thats why the strengthen the keel ... 40 years ago.
I'd keep going, but I'm just blown away by how you got to +5 on this. You don't seem to know anything at all about you're talking about. You're mixing and matching things in ways that makes them all simply completely false statements.
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