THE ZUMWALT AND THE RAIL GUN

[Marlin]

Maybe this should be in Navy threads but it does have some general interest.


THE ZUMWALT AND THE RAIL GUN: THE ENERGY HUNGRY NAVY

Speaking of railguns, another energy-intensive weapon system that could come into play is the Navy's new laser weapons system (LaWS). Unfortunately, the power requirements for the Navy's Rail Gun appear that the Navy will not be able to do any run and gun maneuvers. It is estimated that the ship would have to be at full stop to rapid fire a rail gun. Of course that could change with a different power plant.

As the technology advances, and faced with rising and unpredictable fossil fuel costs, the Navy's next-generation of surface littoral class combatant ship will leverage electric ship technologies in conjunction with new smaller nuclear power plants with the design characteristics of better speed, weight, maneuverability, range, and cost—and capable to power multiple directed energy weapons at full speed.

http://energyfromthorium.com/2014/04/04/zumwalt-rail-gun-energy-hungry-navy/

[fleur]

It looks great project by the navy.

[HydroDave63]

perhaps it will be powered by fusion?

[DrRem]

check it out 

http://www.onr.navy.mil/media-center/fact-sheets/electromagnetic-railgun.aspx

[HydroDave63]

check it out 

http://www.onr.navy.mil/media-center/fact-sheets/electromagnetic-railgun.aspx

We did, about 4 years ago....

Back on topic (assuming this thread still continues to exist) ... this gizmo is still looking for a problem to solve. Dissecting the parent Fox article from which Blaze was quoting:

"It bursts radially, but it's hard to quantify," said Roger Ellis, electromagnetic railgun program manager with the Office of Naval Research. To convey a sense of just how much damage, Ellis told FoxNews.com that the big guns on the deck of a warship are measured by their muzzle energy in megajoules. A single megajoule is roughly equivalent to a (1) 1-ton car traveling at 100 mph. Multiple that by 33 and you get a picture of what would happen when such a weapon hits a target.

Ellis says the (2)Navy has invested about $211 million in the program since 2005, since the railgun provides many significant advantages over convention weapons.(3) For one thing, a railgun offers 2 to 3 times the velocity of a conventional big gun, so that it can hit its target within 6 minutes. By contrast, a guided cruise missile travels at subsonic speeds, meaning that the intended target could be gone by the time it reaches its destination.

Furthermore, current U.S. Navy guns can only reach targets about 13 miles away. The railgun being tested today could reach an enemy 100 miles away. (4)And with current GPS guidance systems it could do so with pinpoint accuracy. The Navy hopes to eventually extend the range beyond 200 miles.

"We're also eliminating explosives from the ship, which brings significant safety benefits and logistical benefits," Ellis said. In other words, there is less danger of an unintended explosion onboard, particularly should such a vessel come under attack.

Indeed, a railgun could be used to inflict just such harm on another vessel.

Admiral Carr, who calls the railgun a "disruptive technology," said that not only would a railgun-equipped ship have to carry few if any large explosive warheads, but it could use its enemies own warheads against them. (4)He envisions being able to aim a railgun directly at a magazine on an enemy ship and "let his explosives be your explosives."

(1) Ok, mildly impressive, that is roughly the muzzle energy of a 16"/50 in a somewhat smaller package (although the Blaze video showed enough equipment being used for the gizmo that an LPD-17 class would be needed to carry one of them. I don't suppose these Dahlgren fanboys have ever heard of "windage losses"? This is a giant gopher gun trying to do the job of a .30-06!

(2) The timing on sinking $211 million into this project starting in 2005 couldn't have been any worse. Keeping this helped the decision to defund a high-tech weapon that could defend or attack at the speed of light, the THEL (Tactical High-Energy Laser) which could have been deployed on ships and land in time for the 2006 Israel-Lebanon rocket war. Oh, but that was an Army project, therefore it must suck and is probably painted green and not haze grey.

(3) 6 minute delivery time. Ok, if the enemy is answering anything better than "Ahead 1/3", the target has moved several ship lengths in that 6 minutes. Oh, but wait, GPS makes everything better! Once again the Dahlgren fanboys assume: (a) real-time intel of exact fix of moving target at 100-200 miles. Excuse me, that's why we still use that primitive semi-active homing radar on our missiles (b) Our likely enemies won't jam radar, except that Iraq used GPS jamming in 2003, anyone can buy GPS jammers today on eBay, and our likely enemies will be using GLONASS and/or GALILEO backup. The only safe assumption in the next war is that GPS will be jammed.(c) how is the steering on this wonder shell going to work? Using an equation that I doubt is taught at Naval War College anymore

d = 1/2* a * t²

for a 20 ft. long accelerator and a muzzle exit velocity of 7000 ft/sec, yields roughly 20,000 G acceleration. Got any shock-hardened steering fins or internal electronics to handle that? Din't think so. At Mach 7, that projectile is also going to have awesome heat on its leading edge surfaces from atmospheric drag. In fact, let's ask...anyone here in the audience done a VERTREP? Get zapped while discharging skin-effect charge? The rotor blades are doing a lot less than Mach 7.

(4) Ok, history pop-quiz for Adm. Carr and company. Name the last guns-only naval engagement where a major surface combatant took a direct hit to the magazine. Pencils down, everyone. May 1941, HMS Hood . Even that is questionable because the boiler explosion may have blown through a transverse bulkhead to the powder mag, in addition to the other 15" shells in Bismarck's bracketing barrage. Point being here, it would be a difficult shot at best due to motion of target and time to impact. Bismarck did it with direct line of sight, surface search radar and a lot of practice. The wonder shell at 100 miles will have none of those 3 going for it.
   The Adm.'s other point, regarding damage to the receiving ship, is moot in modern times as well. In no way minimizing the injuries to the crews, USS Roberts had to be towed after one mine strike, Stark after two non-propulsion superstructure hits, Cole after one hit similar in scope to a lightweight torpedo or 5" shell. In other words, several modern warships have proven that with $10,000 or less in ordnance, they are taken out of action. Hulls of 1/2" of steel or aluminum laminate aren't capable of stopping the threats in modern naval warfare. This is why the future aggressors tend to build as many ships of a class as possible, with as much offensive missile capability  and point defense as possible.