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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.
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.
Why don't you read what a railgun is and how EMPs are generated?
And EMP is generated by having a very high electrical current somewhere. The better that current couples to the far field, the faster that current happens, and the larger the current is all contribute to the magnitude of the EMP. Railguns involve a very larger current, and require it to be applied over a loop with some amount of area to it, so it covers the first and third point well, and just only partially covers the speed one because they are kind of slow compared to other high current devices.
I've worked with small railguns before on plasma experiments. While pulsed plasma experiments already create EMI nightmares if you make any mistake in shielding or groundloops, the railgun has destroyed electronics in diagnostics near by that needed to be rebuilt and better designed. While not on the spatial scale of an EMP by a nuclear bomb (or even a well designed Marx generator...) it does require hardening and careful design of electronics in the vicinity. A lot of military equipment is already hardened anyway, but just making parts of a railgun functional and surviving itself already go a long ways there anyway.
Not that there is that much sensitive electronics needed to make it work, most of it is simple, robust high power electronics, and the sensitive stuff is just there to report on its performance. I don't know what types of switches, etc., they use on the large scale railguns, but if they use things like ignitrons, the basic parts of the railgun will be large capacitors and vacuum electronics, which are very robust against voltage spikes unlike silicon stuff.
Currently railguns have about the same muzzle velocity as a WW2 battleship cannon. ... There might be some exceptions. I think some of the giant land guns might have had higher muzzle velocities.
WW2 battleship "cannon" (actually "guns" as they had rifling), up to 18" bore, were the longest range conventional guns ever, although the accuracy deteriorated beyond about 20 miles. Anti-aircraft guns had a higher muzzle velocity, but being smaller bore did not have such range (air resistance had greater influence). There have been higher velocity and greater range unconventional guns such as with additional firing chambers up the barrel, and the experimental German WW2 "Arrow gun" which fired a long thin shell with tail fins out of a larger bore barrel by means of a segmented wooden jacket (a "sabot") which fell away after leaving the barrel.
The germans had a big gun they used against the French and I think there was another one built in the middle east somewhere but it escapes me. Regardless, the weapons were too large to really be practical. They were big white elephants that accomplished very little compared to their cost.
In their day they were not white elephants. The Western Front in WW1 was static so those big guns, usually railway mounted (not to be confused with "rail guns"!), were useful for hitting things like enemy railway junctions miles behind the front, even though it took days to set one up and about an hour to fire each shot. A specially modified one was even used to hit Paris 70 miles away, more as a terror weapon because its shells dropped with no warning from the stratosphere like a modern ICBM. In WW2 two were used very effectively to hammer the Americans at the Anzio landings. The Germans also had massive seige guns which went for explosive power rather than range such as the "Big Berthas" of WW1, technically howitzers, which were very effective at destroying fortifications at short-ish range such as at Liege in 1914.
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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