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U.S. Navy to Deploy Rail Guns by 2011
Walter Francis writes "The U.S. Navy has apparently been busy. They have been focusing heavily on the next generation of weapons and propulsion systems, including Microwave, Laser, and Electromagnetic-Kinetic weapons, more commonly known as railguns. What specifically surprised me was the fact that the Navy plans to deploy these systems as early as 2011, on their DD(X) frigates. The range of these rail guns is estimated to be over 250 miles."
Build your own railgun Today! Kids love this one!
there was something on some show on Discovery (i think?) about how there is interest in basically dropping large steel rods from really really really high up and use some minimal navigation..... the idea is that they would fly like a "smartbomb" and when going at their terminal velocity (or however fast they can get) they don't even need explosives to cause massive destruction apon impact.....
did i dream this? i don't think so but i guess it's possible. then again i didn't think rail guns or private space flights were coming anytime soon either.
Railgun project
Could this gun be used to shoot stuff into orbit? Or, to hit stuff in orbit?
The lowest commonly-used orbits are in the 200-300 mile range, so this couldn't hit them. Even something in a 100-mile transfer orbit is iffy. However, with good enough targeting, it could hit a ballistic missile during boost or re-entry, and could probably hit any aircraft.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
Cost effectiveness
Is it? All that energy has to come from somewhere. If you're charging your railgun with a few hundred gigajoules of energy, you're burning a LOT of fuel. For a Nuclear Vessel, this wouldn't be that big of a deal. It would simply need to carry a bit more material, or double its refueling stops. (e.g. Instead of every 10 years, they refuel every 5 years.) But these ships are Gas Turbine powered.
rate of fire
This one I definitely don't follow. Where's the energy coming from for a high rate of fire? Does the captain have to order a pre-charge cycle? Would that mean that he'd be able to fire 5-10 shells before having to wait for a 10-20 minute recharge cycle? That's going to have a serious impact on the ship's tactical ability.
Also a bit of safety thrown in- the rail gun rounds require no propellants (read: explosives), so there's no the problem of a hit to a turret sparking off a chain reaction of explosions.
Fair enough. Magazine hits are always a big problem. But couldn't one argue that the magazine storage no longer matters when fighting battles with such powerful weapons? If you're hit by a nuke/railgun/maser/large missile, your ship is dead anyway.
What this effectively does is put the firepower & range of the battleships into the smaller ships.
This is definitely nice. But what I'd like to know is if military doctrine has swung back in the direction of Battleships? AFAIK, the invention of the Aircraft Carrier made Battleships obsolete. Since a carrier can launch planes at nearly any range (even outside the 250 miles of the Railgun), it has far better strike capability. In addition, pilots provide intelligence to both the offensive weapons and evasive maneuvers that not even a missile can achieve.
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Don't forget ricochet range. A projectile that skipped off the ocean (for example) could wind up somewhere much farther downrange than 30 miles.
I've seen plain old ordinary machine gun rounds do some amazing and unexpected things. I expect that scales with velocity.
Interesting point from the article - the author sees this system fitting into existing 5" gun mounts, and sees one gun as being able to deliver equivelent fire as a squadron of F18s. That means destroyers become as powerful as aircraft carriers.
How about that - the return of the battleship.
DG
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What's happening by and large is that most countries are spending less and less on the military.
America spends more than say Europe, but has declined quite a bit from the Cold War peak of the late 80's. Most notable is that the absolute size and war fighting capability of the Army has declined dramatically from the Gulf War 1 era, particularly sea lift. The US isn't capable of something like Gulf War 1 anymore. All we have left is strategic bombing or Nukes which is a poor choice.
Current defense spending seems focused on "stand off" capabilities where the US can inflict damage on adversaries while putting few of it's servicemen at risk. The model seems to be Serbia of the late Nineties where Clinton led a bombing campaign that helped bring Milosevic to the bargaining table.
Rail guns, long range missles, air superiority, and various precision munitions including cruise missles and bombs are all useful things to have with a military facing uncertain threats from unstable countries (Pakistan, Saudi Arabia, Iran all come to mind). But it's only part of the package and the ability of the US to decisively defeat an enemy by taking over their territory and more importantly destroying their military is not very high. [Hitler, North Korea, North Vietnam, Serbia, and Saddam all had their military forces intact despite extensive bombing]
Part of the problem is an unwillingness to face real conflict and the sacrifices on a society that War (which is *always* destructive) requires. The main reason I suspect however is that there's a lot more money in systems like the F 22 or Rail Guns than creating an army with sea lift capability that can destroy an adversary's military and therefore stop things which are contrary to US interests (like say, a dirty bomb in Chicago assembled with Pakistani help as a hypothetical).
Stand off bombing has not served to destroy any military, and it only serves to encourage adversaries to negotiate and isn't decisive. Milosevic like North Vietnam had his own reasons to bargain and the bombing campaign only helped wasn't decisive.
It's also time to get realistic. "Terrorists" are usually allied with significant elements in unstable countries that have factions in the military and elites. Significant elements of Pakistan's Army and Intelligence services for example are PART of the Taliban and Al Queda network. They can however be deterred from helping nuke a major American city if there is a realistic chance that doing so would remove them and their comfortable regime. And so far America's woeful war-fighting capability is very good at bombing specific targets and very bad at removing regimes to provide that deterrence.
Conservation of momentum. You cannot blow a projectile into "harmless" bits, because the total momentum of the pieces remains the same. Instead of getting hit by one big projectile, you get hit by a bunch of dust, or vapor, or droplets of liquid metal. The total impact impulse will remain the same.
You also can't just deflect the projectile, because the force applied to deflect the projectile would be equally applied to the deflector device. Even if you did this via a magnetic field, the deflector would suffer damage.
There's simply not much you can do to stop a projectile moving at such velocities.
All kinds of funny in the replies (I read them all at +1 -- pity me), but not much serious.
:)
For example -- even the first generation railguns have a muzzle velocity (intentionally limited) of 2.5 km/s (which is Mach 7.5, presumably at sea-level pressure -- the article doesn't say). That's awesome for aiming, time-of-flight, and kinetic energy delivery so great you don't even need messy exposives.
But, what about the sonic boom? I mean, even a small thing crossing the speed barrier makes a noise (ref: a bullwhip) -- how loud will it be on deck with n of these things breaking the sound barrier every 10 seconds?
Will they enclose them in something, build a sound baffle of some kind, or just issue really good hearing protection devices for those working in the vicinity?
Sorry to be serious and all, but I'm just curious
everything in moderation
A friend and I started building an EM rail gun for a high school science project in 1985. We didn't even know about any military projects. We just thought it was cool to accelerate a nail using solenoids. It was years later that I found out our idea was being pursued by the military, and I looked up what I could find on the projects to see how it differed from ours. Besides bigger magnets and more power, it functions very much like what we built. In our case, the inside of the gun barrel had a "railroad track" of wires that used the metal projectile to complete a circuit and conduct electricity (through the projectile) to the correct solenoid (the one that would continue to accelerate the projectile). The only problem we had was that part of the momentum of the projectile would be thwarted by the fact that the iron in the nail would stick to the wire when current was passed through. The military solved this problem by using a tungsten rod positioned above a wad of metal foil (iron or steel). The metal foil completes the circuit and also, due to the extreme amounts of electricity, vaporizes. The foil plasma vapors are then pulled along the magnetic field just like the nail in our experiment, but without the sticking problem. The accelerating (and expanding) vapors push the projectile through the barrel, causing it to exit with astounding velocity. This kind of weapon goes through armor plating like a knife through butter.
GreyPoopon
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I was an FTG for six years (basically electrician for big guns). I can't imagine how they are going to get a fire control solution for a target 70 miles away. Without guidance, and at that distance the different weather cells between you and the target would throw the round off target.
I stood about 100 yards away from the New Jersey when she fired all guns starboard. The heat & energy from those guns was incredible. Image an order of magnitude higher. Those little aluminum FFG's would melt their superstructure with one round.
Range of 250 miles? That's impressive.
The era of the big gun pretty much ended with the battle of Midway. After that, it became obvious that aircraft carriers could both defend themselves and attack enemy shipping without need for battleships and their guns. (Or, more to the point, without big guns and the battleships needed to haul 'em around.)
But I wonder what this development means? The railgun projectile is better in several respects than a missle: cheaper, higher rate of fire, harder to spoof or shoot down, apparently more hitting power. It seems to me that this railgun is closer to carrier based aircraft in relative performance than any guns have been since before WW2.
It's almost enough to make one think that the big gun could be effective again. Envision the "bad guys" having a submarine with railguns sneaking up to within 200 miles of a carrier battle group. It could surface to rapidly launch a few dozen hypersonic projectiles at the carrier. If it could launch a big salvo rapidly enough, the carrier would be in a world of hurt. The sub probably wouldn't survive the counterattack, but to disable a carrier that's probably a good trade.
Can an effective ASW umbrella be extended to beyond the range of these guns?
Hmmm.
With reasonable men I will reason; with humane men I will plead; but to tyrants I will give no quarter. -- William Lloyd
Iirc the impact area of a sonic 'boom' is the cone created by the leading edges of the projectile, and it extends laterally away as the projectile moves at greater than mach 1 (not just while it 'breaks' the speed but at all times when it exceeds the speed). This means that the crew and the entire ship will never be in contact with the shock cone, so it will essentially make no noise at all during travel. It will make noise im sure as its fired, but probably nothing compared to a gunpowder projectile.
Am i right, or has high school physics failed again? (or rather did i fail physics...)
jeff
What I meant is that it is much smaller than cannons of comparable power -- of which there really aren't any. Being able to fit something with that much range and power on a destroyer is a big step forward.
A cruise missle isn't really that small -- currently they are fired only from destroyers and cruisers, or large submarines. Each missile is large, having to carry both the fuel and the warhead. While the rail gun itself is larger than a cruise missle and launcher, each rail round is much smaller and much safer since it isn't a mix of high explosives and rocket fuel waiting to be hit by enemy ordinance. And if its speed you want, then the limiting factor is mass, and you can get a lot more rounds for less mass with a rail gun.
I don't see what the distance to the target has to do with its value... Why spend half a million destroying a warehouse when you can use a comparitively free lump of metal?
All in all, I think rail guns are a vastly positive improvement in weapon mobility. I don't see missles as having any advantage, outside of extra range.
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Methinks "a lot"...
Without the hot expanding gasses from conventional cannons the heat might not get out of hand. Right?
That's being replaced by 4 advanced design turbines that will put out about 80 megawatts, used to power electric ship motors and provide power to the rest of the ship.
Sorry to interject, but 80MW is NOT sufficient power to run both the weapons systems and the propulsion. Keep in mind that 80MW is *maximum* power output. Maximum power output will drain the fuel stores extremely fast. Presumably, some of that power will be automatically assigned to defensive and communication systems such as RADAR, GPS, Radio, Satellite Uplink, Targeting, and simply keeping the lights on. With the remaining power, the ship can either move under military power or charge the rail gun. It simply doesn't have enough power to do both.
Even more interesting is that the article spoke of adding Masers to the inventory of high energy weapons. Now the commander will have one MORE decision to make: Does he move the ship, charge the railguns, or fire the Masers? He'd better make the right decision, because the boat will be sunk if he makes the wrong one. Not to mention that his ship wouldn't be able to sustain battle for more than a few hours. At 80MW, the ship will be running about 130 liters of fuel through the turbines each minute. He simply can't stay in a firefight for very long that way.
No, unless they start equiping these ships with Gigawatt nuclear reactors, they won't be able to help very much in a surface engagement. What they WILL be able to do (and thanks to the posters who pointed this out to me) is bombard stationary installations like RADAR stations, Airfields, and beach defenses. The Marines will love them, and they'll cost less than pulling the battleships out of reserve.
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Probably not, but from the articles I've been reading, they're having one hellva time with barrel friction at this stage of development. Every shot is quite literally ripping the barrel apart. Once they nail that down , it'll just be a matter of inflight guidance. Other fun facts-- Did you know they will need to divert power from the engines to bring this thing online? Having Scotty divert power to the weapons has a whole new meaning ^_^
How prophetic of me...
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Is it just me or is the US on some utterly bizarre wild goose chase, spending (read: WASTING) trillions developing military and weapon technology to outdistance itself technologically from other world armies by a factor of 100 instead of (the supposedly insufficient) factor of 50? Just WHO are they going to fight with their Seawolf subs, Aircraft Carriers, railguns, and that entire quadgizillion-consuming army? Terrorists? North Korea? Europe?
/.'ers), wouldn't it be nicer if your government was using YOUR taxmoney to do YOU some good?
Take a look at the UK for an example. They opted for a small fleet of SMALL aircraft carriers that are designed to rush in and handle local skirmishes and cost a helluvalot cheaper than their American leviathan counterparts and their trailing battlegroups (which are there just in case the Soviet Block comes back together and stops being poor all of a sudden, Marxism is revived, all western culture as we know it is abolished there and the Japanese decide to attack Pearl Harbor. Again.)
Yes, I know (;-)), A real live railgun will give any fps gamer who can pronounce "quake" a hard-on, but guys (I'm talking to the americans among us
Get you more IT jobs? Encourage tech-oriented businesses with tax levys? Hell, give it to NASA and have them build a space elevator before China does, that'll be a sure way of giving all us geeks an even bigger erection...
All you have to do is look at [modern, developed, not-dirt-poor] self-oriented countries such as Australia or Germany to see how useful a taxdollar can be when put on the right track.
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