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Navy Debuts New Railgun That Launches Shells at Mach 7

Soulskill posted about 10 months ago | from the playing-instagib-on-the-high-seas dept.

The Military 630

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."

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Glitterboyz on the way (0, Offtopic)

Anonymous Coward | about 10 months ago | (#46706493)

Oh yeah. Time to take down some dragons and some skullheads.

Re:Glitterboyz on the way (-1)

Anonymous Coward | about 10 months ago | (#46706651)

That's so nice!!! Now they can bomb children and weddings^W^W^Wterrorists much more efficiently!

Re:Glitterboyz on the way (2)

Z00L00K (682162) | about 10 months ago | (#46706715)

Mount a downsized version on the A10.

Re:Glitterboyz on the way (4, Insightful)

Immerman (2627577) | about 10 months ago | (#46706819)

The railgun might fit, but where are you going to put the nuclear reactor to power it?

Re:Glitterboyz on the way (1)

alexborges (313924) | about 10 months ago | (#46706827)

Whats the recoil on this thing?

Re:Glitterboyz on the way (-1)

Anonymous Coward | about 10 months ago | (#46706853)

Nope, time to kill some dark-skinned people.

No jetpacks yet... (4, Insightful)

occasional_dabbler (1735162) | about 10 months ago | (#46706511)

...but at least part of the future is here already.

Re:No jetpacks yet... (2)

aliquis (678370) | about 10 months ago | (#46706643)

Rocketpacks have been around for long, they run out quickly though.

Jetpacks I think they also used later. (One of the guys really into it died (I don't think it was from the pack.))

IANA Physicist, So... (4, Interesting)

errxn (108621) | about 10 months ago | (#46706537)

...Can someone who is explain where the big fiery explosion out of the railgun is coming from, if this thing is electromagnetically driven?

Re:IANA Physicist, So... (5, Informative)

Anonymous Coward | about 10 months ago | (#46706569)

Hot expanding gases, you're pushing a projectile at Mach 7 through air that doesn't really have anywhere to go.

Re:IANA Physicist, So... (2)

errxn (108621) | about 10 months ago | (#46706597)

OK, hot, yes, but wouldn't they need something combustible to actually erupt into flame? Or what am I missing?

Re:IANA Physicist, So... (5, Informative)

PortHaven (242123) | about 10 months ago | (#46706635)

Oxygen, it's in the air...

fine vaporized particles of metal...


Re:IANA Physicist, So... (5, Funny)

Moheeheeko (1682914) | about 10 months ago | (#46706641)

Oxygen is pretty combustable if you get it hot enough. Friction is a bitch yo.

Re:IANA Physicist, So... (1)

Anonymous Coward | about 10 months ago | (#46706667)

you need 3 things for fire:


Oxygen is flammable all on its own, it is essentially both fuel and air. Friction gives you the heat. What you see is the air itself burning. The good news is air density is low, so it can't run out of control and ignite the entire atmosphere. The bad news is, this is actually slowing down the potential top end speed of the projectile, you are getting resistance immediately.

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706719)

Oxygen is flammable all on its own, it is essentially both fuel and air. Friction gives you the heat. What you see is the air itself burning.

Care to give the actual chemical reaction for that?

Oxygen+Heat-> ???

Ozone doesn't work because that would be endothermic, not anything like combustion releasing energy.

Re:IANA Physicist, So... (2)

Ferrofluid (2979761) | about 10 months ago | (#46706799)

Oxygen is most definitely not flammable. Please take a grade-six science class.

Re:IANA Physicist, So... (0, Troll)

alexborges (313924) | about 10 months ago | (#46706839)

Why you trollin? Everything is flammable.

Re:IANA Physicist, So... (0, Offtopic)

Anonymous Coward | about 10 months ago | (#46706851)

then explain it better dipshit. The guy is trying to help and all you wanna do is tear him down without contributing. Way to be a loser. How about you try again.

Reply to Comment? (0)

aliquis (678370) | about 10 months ago | (#46706957)

Oxygen is most definitely not flammable. Please take a grade-six science class.

But your comment is!

(Damn is weird, I wondered what page I was on, if it was some blog post I had ended up in or whatever.) .. no html quote tag in it either? I'll keep it and post this way anyway just to show how stupid it is.

Re:IANA Physicist, So... (1)

TangoMargarine (1617195) | about 10 months ago | (#46706887)

If oxygen was both fuel and air, why the hell would we have two separate categories then?

Re:IANA Physicist, So... (2)

Assmasher (456699) | about 10 months ago | (#46706711)

The nitrogen under pressure remains inert, but the oxygen will combust at those levels. There's a great video of the plastic block they were testing with years ago with a huge wall of flame behind it as it traveled at mach 5 iirc...

Re:IANA Physicist, So... (2)

Ryyuajnin (862754) | about 10 months ago | (#46706721)

"When air is compressed very quickly, it can reach high temperatures. In this demonstration we show how cotton wool can reach the point of auto-ignition by quick compression of air in the fire syringe." http://www.youtube.com/watch?v... [youtube.com]

Is anything actually burning? (5, Interesting)

Immerman (2627577) | about 10 months ago | (#46706873)

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.

Re:IANA Physicist, So... (5, Informative)

MozeeToby (1163751) | about 10 months ago | (#46706933)

"Flame" is nothing but superheated gases. You can have a flame without combustion if you raise the temperature some other way. In this case it's electrical heating, ram air pressure, and simple air friction.

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706571)

Atomizing particles.

Re:IANA Physicist, So... (5, Informative)

peragrin (659227) | about 10 months ago | (#46706577)

It is called plasma. It happens when you heat gases beyond a particular limit.

A 23 pound slug traveling at Mach 7 is displacing a lot of air very quickly.

Do you think that air will get colder?

Re:IANA Physicist, So... (1)

Redmancometh (2676319) | about 10 months ago | (#46706963)

Just think of a giant fire cylinder, but in reverse, and much larger.

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706587)

Superheated air. You don't go from standing to 5,000mph without a little friction. Its essentially plasma.

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706595)

I'm assuming it is the result of atmospheric cavitation, no? Much in the same way these creatures do it? http://en.wikipedia.org/wiki/Alpheidae#Snapping_effect

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706653)

Cavitation is from the liquid turning into a gas when the pressure gets low enough, and then getting compressed back together when the liquid caves in. You don't get that effect in a gas, just more typical slight heating from sound and shocks.

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706689)

^ This, it's cavitation, alright. The atmosphere is a liquid...

Re:IANA Physicist, So... (1)

K. S. Kyosuke (729550) | about 10 months ago | (#46706725)

Liquid? It's fluid, but not liquid, now is it?

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706953)

When you compress it enough it is.

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706629)

Probably some special effects added for coolness factor.


TiggertheMad (556308) | about 10 months ago | (#46706631)

Just speculation but, when you propel something to mach 7, friction becomes a real issue. The SR-71 had a titanium body if I recall correctly, to help deal with temperatures it encountered at Mach 3. It is quite possible that the projectile is very hot and is igniting materials that have lower ignition temperatures.

Re:HOT HOT HOT! (4, Interesting)

Immerman (2627577) | about 10 months ago | (#46706923)

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.

Re:IANA Physicist, So... (2, Interesting)

Anonymous Coward | about 10 months ago | (#46706691)

The currents involved here vaporize part of the structure and the shell. It's a very destructive process. They use something called a "sabot", the actual projectile is inside the sabot. The sabot is what is being driven/destroyed in the process. The problem with railguns is that they are linear scaling. The relationship between the force supplied to the sabot and the current is strictly linear as F=BLI.

So you need an incredible amount of current in a very short time to get an effect like this.

It's not entirely clear what the advantage of a railgun would be, it's very hard on the cannon. Psychology, I guess. It's an inert piece of metal that can't be jammed and is probably hard to spot on radar too.

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706751)

Depending on what they are using for an armature, the fire is plasma created from the super-heating and vaporization of the armature (a conductive media, metal or sometime a gas). As others have mentioned part may be plasma from atmosphere effects.

Re:IANA Physicist, So... (0)

Anonymous Coward | about 10 months ago | (#46706789)

Unless something has changed in the last couple years since I worked in a field closer to that work, the fireball is mostly from arcing, friction issues with the rails, and/or vaporizing conducting elements associated with the projectile. Especially when the projectile leaves the rail, a large arc is created, and there are all sorts of issues of small amounts of metal from the rails and the connection across the projectile vaporizing and making a mess. Last I had kept up on the details, the spray of vaporized metal was a serious maintenance issue, but it was just assumed to be an engineering issue that would be improved upon and practically solved.

All the people saying stuff about heating of the air doesn't make sense, because if that speed caused that much heating, the fireball would be following the projectile. The barrel of the rail gun is not anywhere close to air tight like a normal gun, so it is not that the air would pile up in front of the projectile any more in the barrel than it would on the way out.

inb4 (-1)

Anonymous Coward | about 10 months ago | (#46706539)

inb4 a bunch of douchy socialists whine about not buying democrat votes instead of conducting engineering science for national defense.

Power? (3, Insightful)

asmkm22 (1902712) | about 10 months ago | (#46706545)

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.

Re:Power? (0)

Anonymous Coward | about 10 months ago | (#46706583)

I would bet the Navy plans to put them on large ships with nuclear reactors on board. Given that these scale really well and are a proven technology I don't think the Navy should have a problem. Now making a tank that uses this gun that might be hard.

Re:Power? (2)

Ryyuajnin (862754) | about 10 months ago | (#46706661)

Future Aircraft Carrier, USS-Nikola, to be constructed primarily of Lithium-Ion Batteries.

Re:Power? (4, Funny)

gstoddart (321705) | about 10 months ago | (#46706797)

No, you're mistaken ... that's the USS-Nokia. ;-)

Re:Power? (2)

PortHaven (242123) | about 10 months ago | (#46706671)

New cruisers and carriers just coming out were spec'd to have 3x-6x power generation. New carriers are getting rid of steam catapults in lieu of railgun catapults as well.

Re:Power? (2)

saider (177166) | about 10 months ago | (#46706949)

The catapults (EMALS) are not railguns, they are essentially linear motors. As I understand they use different effects to operate.

Re:Power? (1)

alexander_686 (957440) | about 10 months ago | (#46706737)

Yes. It is going to be powered by (indirectly) by diesel, which is flexible – in the sense that it is widely available, can be used for lots of things, etc. It does not have its own oxidizer, so it is safer to handle, has higher energy density, etc. So a single ship could fire more rounds at a lower cost than a traditional big gun battle ship.

Energy is not the issue – it is the rate of fire. Diesel engines power the supper capacitors, they discharge to fire the gun, and then fill them up again. I have read that this cycle might be measured in minutes instead of seconds. How big of an issue that it will be is a big question.

Re:Power? (1)

Immerman (2627577) | about 10 months ago | (#46706971)


I would think these would be a much more natural fit for nuclear-powered vessels, where the capacitors can be recharged far more quickly. Not that I doubt they'll be used in other scenarios as well, but for high firing rates you'll want *real* power.

Re:Power? (1)

Anonymous Coward | about 10 months ago | (#46706781)

AFAIK most large non-nuclear USN ships are turbo-electric, which means they have some huge generators. The Ford class carriers (and the F-35 for that matter) are also being designed to be able to generate huge amounts of electric power. The Navy is making serious efforts to future-proof their toys with regards to the expected huge energy requirements of future weapon systems.

Re:Power? (0)

Anonymous Coward | about 10 months ago | (#46706835)

The amount of energy it takes isn't the problem, it's how fast the energy has to be released. Your choices are basically a capacitor or a flywheel (specifically a compensated pulsed alternator or "compulsator", as it is sometimes called, which releases energy quickly as a DC pulse). I don't know which is used in the lab, but on a ship you would probably almost certainly go with the flywheel (significantly higher energy density relative to volume and mass).

Re:Power? (0)

Anonymous Coward | about 10 months ago | (#46706925)

They are going to be mounted on nuclear powered ships that are freeing up a lot of room - steam catapults, HE ordinance storage, etc. They are trying to replace all energy systems on modern ships with one unified power source: the reactor.

More room for a reactor, armor and shielding - longer range with cheap warheads - ships that don't explode because you set off their arms cache. If I was younger, I'd be willing to serve on one of these vessels.

Shoot The Moon! (1)

Ryyuajnin (862754) | about 10 months ago | (#46706559)

It'd be worth the court marshal...

Re:Shoot The Moon! (0)

Anonymous Coward | about 10 months ago | (#46706713)

That's be neat! Sadly, this weapon only has a 100 mile range. You'd need to increase the range by 2,389 times that to hit the moon. ;(

Re:Shoot The Moon! (1)

swaq (989895) | about 10 months ago | (#46706845)

Mach 7 is about 1/5th of the way to escape velocity, at least.

Re:Shoot The Moon! (0)

Anonymous Coward | about 10 months ago | (#46706881)

No, just enough to get out of our atmosphere, once your in space it should continue forever.

Re:Shoot The Moon! (1)

Marc_Hawke (130338) | about 10 months ago | (#46706959)

No, you just have to get it out of the atmosphere and aimed right. I'm pretty sure mach 7 is good enough for 'escape velocity'.

Re:Shoot The Moon! (0)

Anonymous Coward | about 10 months ago | (#46706859)

We have the technology, the time is now, science can wait no longer, children are our future, America can, should, must, and will blow up the moon!

"Low Cost" (1)

Anonymous Coward | about 10 months ago | (#46706561)

Would any of our resident physicists care to compare the "cost" in terms of energy for firing the railgun vs firing shells with conventional guns? Just curious.

Re:"Low Cost" (4, Informative)

PortHaven (242123) | about 10 months ago | (#46706683)

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.

Re:"Low Cost" (1)

WilliamGeorge (816305) | about 10 months ago | (#46706685)

It isn't built to compare with cannons / guns, which our naval ships no longer use for ship to ship or ship to shore engagement. It is designed to replace or augment missiles, and the cost of the round fired is ~$25k which is an order of magnitude or two less than similar-ranged missile technology.

More Testing to Come! (1)

Anonymous Coward | about 10 months ago | (#46706573)

I hear they're going to be testing this on the Fox Archipelago off the coast of Alaska. I hope everything works out and that this doesn't have any nuclear proliferation implications at all.

Re:More Testing to Come! (0)

Anonymous Coward | about 10 months ago | (#46706717)


SWATH, not Catamaran (4, Informative)

n1ywb (555767) | about 10 months ago | (#46706591)

It's a "Small-waterplane-area twin hull" or SWATH, not a catamaran. http://en.wikipedia.org/wiki/S... [wikipedia.org]

Incom.... (2)

TFlan91 (2615727) | about 10 months ago | (#46706593)

"They are firing, sir!"
"Prepare the counte...."

Seriously... 100 mile range? At 5000mph? That range doesn't add up to me, but regardless, whoever is on the receiving end of this bad boy doesn't stand a chance to defend themselves

Re:Incom.... (0)

Anonymous Coward | about 10 months ago | (#46706707)

Well, that's 83.333 miles a minute.. so it'd take about 1.2 minutes to go 100 miles.

Why doesn't the range add up?

Re:Incom.... (1)

Talderas (1212466) | about 10 months ago | (#46706771)

The big guns on the Iowa were about a 25 mile range and were fired at just over 2,000mph. The projectile weighed between 1,900 and 2,700 pounds (compared to the 23 in the railgun).

space requirements and fire rate (0)

Anonymous Coward | about 10 months ago | (#46706601)

After reading the article and seeing the pictures I notice a giant capacitor bank in the background of one of the pictures.

How much space does the entire setup require and maybe more inportant is how fast can it fire and how much energy is stored in the banks.

The danger of high explosives maybe offset if you would need a nuclear reactor onboard or if your capacitor bank catches fire or explodes.

Re:space requirements and fire rate (1)

Amtrak (2430376) | about 10 months ago | (#46706645)

Since the navy already runs nuclear reactors on ships I don't think they are that worried about them. However, the capacitor bank exploding could be interesting. I guess they would have to put it somewhere armored on the ship. I would also think that they might have trouble providing cooling for all the electrical equipment as well.

Re:space requirements and fire rate (0)

Anonymous Coward | about 10 months ago | (#46706893)

You don't need that much "armor" for a capacitor bank, especially if it is well designed. The energy density of the capacitors is a lot less than explosives, and if properly fused and setup, an accident won't dump the entire bank's energy. You end up with a single cap blowing its top off, with the energy stored in its section or less, and usually a mess of metal and oil. A sheet of acrylic can block it in most cases, just it will look ugly afterwards. And I've yet to see one catch fire despite the amount of sparks and smoke it makes, and there are probably design changes that can be made to make it even less likely to catch fire.

Re:space requirements and fire rate (1)

nevermindme (912672) | about 10 months ago | (#46706919)

Cooling for a Ship weapon...wonder where there is a unlimited supply of 80deg water that has be boiled for cooking/drinking/showers?

Re:space requirements and fire rate (0)

Anonymous Coward | about 10 months ago | (#46706947)

They are cruising around on top of a mighty big heat sink.

EVE Online (2)

war4peace (1628283) | about 10 months ago | (#46706615)

That's not even a 75mm railgun size. Can I fit it on my Velator? :)

Re:EVE Online (0)

Anonymous Coward | about 10 months ago | (#46706695)

I can sell you some Minmatar. That'll solve your problem; they tell me (in between shots of Vitoc) that enough duct tape makes anything fit.

How often can they fire? (1)

aliquis (678370) | about 10 months ago | (#46706623)

As in can it shot down missiles or not? And if so which ones?

Re:How often can they fire? (0)

Anonymous Coward | about 10 months ago | (#46706979)

Looks hand loaded, so ICBMs maybe. Honestly, the Navy's laser tech is better for defense or will be. Otherwise, they would need to focus on scaling it down. Don't need a mortar when an aimed high velocity slug(s) would do better at taking down a missile.

With all these new technologies coming to the military, I wonder if and when a break through in generators will occur.

"debut?" (1)

Tyrannicsupremacy (1354431) | about 10 months ago | (#46706627)

Haven't they been showing this thing off for a few years now? The shipboard trials aren't even due for another two years. That's not really much of a debut at all now is it?

Almost lunar escape velocity... (1)

Anonymous Coward | about 10 months ago | (#46706633)

2.38 km/s or 5324 mph. In vacuum and lunar gravity, this probably do it. Put it on the moon, solar power it, change out the shell with buckets with high-g transponders and Gerald O'Neil's vision of a mass driver to throw moon stuff to build a L5 colony is a reality! IMHO, it's much higher priority that any mission to Mars. Or restarting the fracking Cold War.

Re:Almost lunar escape velocity... (1)

K. S. Kyosuke (729550) | about 10 months ago | (#46706945)

For lunar launch applications, a much better option would probably be a long open rail. You're not size-limited.

Finally.... (1)

PortHaven (242123) | about 10 months ago | (#46706701)

We can take on kaiju...

Finally (5, Funny)

bitt3n (941736) | about 10 months ago | (#46706723)

At last the US Navy, for so long the joke of the high seas, will become a force to be reckoned with.

Aiming and targeting? (1)

mveloso (325617) | about 10 months ago | (#46706733)

With these sort of weapons, how does the navy effectively target something? It's ridiculous to think the Navy would be targeting say, a truck. Would they just stay offshore and throw these at a building or something?

Re:Aiming and targeting? (1)

alexander_686 (957440) | about 10 months ago | (#46706899)

IIRC, the shells will have a guidance system that will allow them to be guided, which is something that they will need if they plan on hitting a moving target – it does take over a minute for the shell to travel 100+ miles – the target will not be in the place where it was when the shell was launched.

Re:Aiming and targeting? (0)

Anonymous Coward | about 10 months ago | (#46706909)

Well considering the M1 Abrams tank can have an accuracy of roughly 35 yards spread at it's 8000 yard range, while moving over rough terrain, even directly scaling that up would indicate this railgun should have a one-mile radius accuracy at it's 200-mile range.

While that sounds awfully low, realize this is assuming it's only as good at the stabilization and auto-targetting systems the Abrams tank has. This would be on a dedicated naval vessel, and be more accurate as a result, and that's before you consider such things as spotters helping the targeting team adjust between shots.

Re:Aiming and targeting? (1)

AxeTheMax (1163705) | about 10 months ago | (#46706939)

They'll target them the same way the USAF targeted the Vietcong with B52 bombers. Fire them in the general direction of the other side, and hope some hit their targets. Doesn't really matter if they hit lots of civilians instead, there's a well established formula to get away with it - have some evidence (or even just claims) that in the right conditions it might catch some combatants.

Holy shit (1)

EmagGeek (574360) | about 10 months ago | (#46706763)

23lb = 10.43kg
5000mph = 2235m/s

1/2 * m * v^2 > 26 MJ

Put into perspective, 26MJ / 3600s ~= 7.2kWh, or about $1 worth of electricity.

How much does 100lbs of black powder cost? (or however much they use to launch shells from battleships?)

I see a huge cost saving for the military depending on how many shells they fire every year in training.

Re:Holy shit (2)

Whorhay (1319089) | about 10 months ago | (#46706905)

I likely takes a lot more electricity than that because the rail gun isn't going to be very energy efficient. I think I saw a large bank of capacitors in the background of the indoor photo. You wouldn't need such large capacitors, or so many of them, if it was only using 7.2kWh. Also the railgun is also firing a sabot of some sort that contains the 23 pound projectile. Regardless the article already pointed out that it is far cheaper to shoot than the chemically propelled shells. What I really want to see though is impact testing, I want to see things disintegrating explosively as a result of being hit by this thing.

Accuracy and moving targets (0)

Anonymous Coward | about 10 months ago | (#46706767)

this thing sounds quite bad for anybody that might live near to a target.

How accurate is this thing at max range (100 sea miles) since its just a dumb fire projectile?

If we look at other long range weaponry I would assume it is a lot less accurate then current missile technology since it would not be able to adjust its trajectory mid flight.

Mach 7? (5, Funny)

K. S. Kyosuke (729550) | about 10 months ago | (#46706801)

Well, judging form the pictures, this is the one disposable razor I wouldn't want to be shaved with.

Is the propulsion truely just magnetic? (1)

Adam Harrison (3610917) | about 10 months ago | (#46706803)

The the projectile leaves the barrel, it is with a fiery explosion behind it. If this is from a rail gun, shouldn't the projectile be push purely by magnetic force, and there be no flames from the barrel?

Re:Is the propulsion truely just magnetic? (0)

Anonymous Coward | about 10 months ago | (#46706889)

When you compress air enough it will ignite. The air left in the barrel when the projectile starts moving forward gets compressed so quickly that it gets super heated and ignites.

The explosion on impact is similar, there aren't any explosives in the round, it's purely kinetic energy being expended very quickly.

Both GA and BAE Railguns will be Tested (3, Informative)

Anonymous Coward | about 10 months ago | (#46706821)

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.

Intercontinental ballistic railgun emplacements (1)

mdsolar (1045926) | about 10 months ago | (#46706823)

Intercontinental ballistic railgun emplacements may end up replacing nuclear ICBMs since a patterned barrage may be more effective, particularly for excavating bunkers to decapitate command and control. The ground penetration problem may soon be licked and the Iranian nuclear threat can be settled through negotiations from a position of strength. Nice work Dalgren!

Another railgun proposal... (1)

floobedy (3470583) | about 10 months ago | (#46706841)

I recall a proposal (at this point very hypothetical) to have a huge railgun arranged in a loop, which would be situated somewhere in the continental US. The projectile would go around and around in the railgun loop, accelerating each time, like a slingshot, until it's flung out toward the target. The projectiles would go so fast that they'd fly out into orbit before coming back down. This would allow us to "shell" any country on earth from some railgun in the US. The "shells" in this case would have so much kinetic energy that they'd level a city block from the shock wave they'd create upon landing.

WHY DON'T WE HAVE THIS ALREADY? It's the ultimate homeland defense.

Baguettes (0)

Anonymous Coward | about 10 months ago | (#46706937)

They make Baguettes in the US also, you know

There must be a money burning contest in the US... (0)

Anonymous Coward | about 10 months ago | (#46706877)

Add up the costs of this, the F35, the NSA, DEA and all the other nonsense and I wager the US could have had an automated industry and military to rival China's and Russia's combined production capabilities manyfold with surplus money left to spare.

So... (5, Funny)

msobkow (48369) | about 10 months ago | (#46706895)

So we're back to throwing rocks.

We just throw them very, very fast. :)

Read this post in the Q3A announcer voice (1)

gman003 (1693318) | about 10 months ago | (#46706897)


Difficult to defend against (5, Interesting)

floobedy (3470583) | about 10 months ago | (#46706915)

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 [wikipedia.org] . 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 [wikipedia.org] or phalanx [wikipedia.org] . 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.

And the advantage of this is? (5, Informative)

bobbied (2522392) | about 10 months ago | (#46706935)


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..

WTF? (1)

benjfowler (239527) | about 10 months ago | (#46706955)

Why the hell does an inert slug encased in a discarding sabot cost twenty grand?

Are the defence contractors taking the piss or what?

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