US navy electro-cannon test successful

The US Navy's electromagnetic railgun project notched up a successful test yesterday. The radical new protoype weapon, operated by the the Naval Surface Warfare Center Dahlgren, fired* shot a hypersonic aluminium slug at approximately Mach 7.5 to generate muzzle energy of 10.6 megajoules. Here's a vid of the test: The …

[umacf24]

Wow -- that _is_ a pleasing video

Probably faked.

[Rob Sked]

Ok . . . .

. . . . when can I buy one?

For "home secutiry" purposes naturally.

[Brian]

I'll take 4

I'll take 4, drop the top on mine and does it come in black?

[TeeCee]

Firing?

Presumably all the people killed in the past by bowfire should complain about being offed by a semantic inaccuracy then?

To fire a bow is a perfectly acceptable term in general use, although the more correct term for the actual act of discharging the projectile (and the order given) is "release". The same could easily apply to railguns, the "draw" being the charging of the capacitors, the "hold" being a state of charged and ready and the "release" being the dumping of said charge into the electromagnets.

Thinking about it, maybe "railbow" would be a better term for the weapon in question.....

[Gavin McMenemy]

Whizz bang!

If this is a railgun why is there flame coming out of the back of the projectile?

My confusion makes Paris Hilton cry.

[Anonymous Coward]

"faked"

To spook the Russians into another arms race? And more funding for these boffins with nothing better to do.

Ballmer for firing better cannons.

[Greg]

@TeeCee

According to Weis and Hickman, a railbow differs from a crossbow in that a) it's Elven in construction, and b) it fires intelligent bolts.

So all you need to do is find your way through Death Gate and you're sorted.

(Spot the nerd currently reading the Death Gate cycle.)

[Dave Bell]

Fired? Shot?

I have a vague recollection of the RN making a careful distinction between "fire" and "shoot" as commands.

In any case, there seems to be more than enough flame for "fired" to be a valid word.

But don't name the railguns after the research centre: it's named for a US Naval officer whose name has already been attached to the guns he designed, around 150 years ago.

And there's also a rather famous book with that title.

[Graham Dawson]

Pedants' Corner

Strictly speaking the correct term for a longbow is "Nock! Loose!" since no fire was involved and all they were really doing was letting go. "Shooting" is what you do with a crossbow, possibly because it has a distinctive "shout", though my etymology in this instance is not very reliable. In this case perhaps they should loudly shout BANG! when they want to fire.

*spends 15 minutes drooling at the sight of a plasma shockwave*

[Edwin]

@Gavin McMenemy

Because dumping 10.6 megajoules through an aluminum slug is bound to cause some burning (of both slug & rails).

Some railgun projectiles actually work on this principle - using a thin metal coating that vaporises into a plasma to conduct the charge, rather than conducting through the projectile itself.

[dv]

old tech, actually

I know of a project like this in late 90's, developed for czech army at CTU FEE Prague. They got to Mach 5 or so muzzle velocity, the supervising officer was VERY pleased, and decided to move the project to military development facility. The gun was able to fire about two times, before the "barrel" (two rails, actually - hence the "railgun" moniker:-)) fused together.

The "flame" (flash) is actually plasma emission, aka lightning; the gun works by two means - mainly Lorentz force induced by a spike current in the rails pulling the slug, and a plasma discharge (a small lightning, actually) induced by an artificial short circuit (very thin wire between the rails, which at the time of "firing" vaporizes instantly and induces a lightning arc) behind the slug.

It is called it "plasma cannon". And the tech is already nearing battlefield deployment, the USofA being the obvious technology leaders.

[Charlie Stross]

Pissed old hack baffled by (not very) new technology

Mach 7.5 sounds a lot more impressive than 2400 metres per second, which is what this is.

It's worth noting that modern tank guns firing APFSHS-DU penetrators routinely achieve 1600 metres per second, that tweaked APFSHS-DU has tested out to 1900 metres per second, and that it's generally agreed that it should be possible to push conventional explosive-driven projectiles to 2000 metres per second in the next generation of guns. So what they've got here is maybe a 15-20% improvement over where the state of the art is with explosive-driven guns at the same level of development.

Meanwhile, did you notice the sparks flying from the underside of the railgun? Serious arcing -- always a problem when you're throwing millions of joules around in under a millisecond -- tends to wreck railguns. And you get arcing when you mix that kind of current with air. Especially damp, salt-laden air (hello, paging the Navy: you are aware that your ships sail on top of seawater which is (a) conductive and (b) tends to splash everywhere? There's a reason naval guns on real warships come with protective caps which are only removed just before firing ...)

Railgun technology isn't new; it's been a hangar queen ever since the Nazis scratched their heads over it in the 1940s. Now DARPA have got it to work about as well as the conventional alternative, in a demo. Nothing to see here, move along ...

[Chris]

Flames

The flames coming out the back are actually plasma caused by the intense heating of the slug.

10MJ is tiny, BAE already have a 32MJ railcannon-

http://www.dailytech.com/BAE+Sports+Most+Powerful+Railgun+Ever/article9791.htm

http://www.military.com/features/0,15240,160195,00.html

All you need is 3,000,000 amps to fire it :)

[Lyndon Hills]

Video?

Seems to have been removed. Maybe it was classified?

[Anonymous Coward]

We're sorry, this video is no longer available

How secret was this test??

[Dr. Mouse]

@Graham Dawson

IIRC, "Nock" in terms of archery is the term associated with putting the bow string in the notch in the arrow. The actual sequence is Nock, DRAW, Loose. (I am no expert, but I do read a lot of heroic fantasy and they tend to research such things, due to pedants complaining if they get details wrong)

Back to the article, this is a seriously cool gun. Where can I get one? :D

Mine's the very expensive coat, with pockets stuffed with cash. Honest.

[Anonymous Coward]

Tampions and Hybrids

@Charlie Stross

The tampion (muzzle cover) that you see on ships in harbour is a ceremonial version - usually polished brass or chromed steel - while tampions used at sea are quite different. They're not removed "just before firing" but rather for a given state of readiness. Given the barrel interior withstands many hot blasts of propellant as well as a projectile scraping past it's rifling, you should be able to see that a bit of salt water isn't really much to worry about. But barrels get cleaned anyway, to maximize their life and minimize cost to the taxpayer. If it comes to it, the round can be fired straight through the tampion, anyway.

Other weapon systems (I won't go into details) use weatherproof membranes which are punctured on firing - it's quite harmless as far as the ordnance is concerned.

Whereas, the experimental 'railgun' may not sound fantastic yet, keep in mind that its muzzle velocity already exceeds even the fastest conventional projectiles. Future iterations will be increasingly impressive. Consider that 12-pound cannon were pretty lame compared to a modern 4.5" naval gun, yet they rely on the same basic principle - an explosive propellant and round.

We may yet see a hybrid weapon using a (relatively small and gentle) conventional propellant followed by a railgun acceletator to maximise the benefits of the new technology and improve barrel life.

[Graham Dawson]

@Dr Mouse

Argh, beaten by my own pedantry! I should have know this one too, they had that exact phrase in Ash: A Secret History which I only just finished reading.

Oh well.

Anyone remember that classic scene in Hunt the Bismark where they intercut between the British gunery officer shouting "SHOOT!" and the german one shouting "FIRE!". When I was a kid that amused me greatly for some reason...

[Anonymous Coward]

Terminology

I'm gonna Gauss yo ass mutha ! ?

Stand well back from the railings..

[Harry]

Is it just me...

or does that look like an upright piano...?

[Chris]

Cool - I wants one...

NOW!

[Sam]

just asking

Can I have a hand-held version?

[Harry]

@me

"Is it just me... or does that look like an upright piano...?"

that would explain the Great Balls of Fire...

[Cameron Colley]

RE: Terminology

I think you'll find a Gauss gun is a different type of gun again. ;~)

I always thought railguns were supposed to blow themselves apart on firing anyhow (William Gibson's fault, I think). Surely, though, even a single-use railgun would be useful if you could fire at a bunker in a suitable ballistic arc?

[Gavin McMenemy]

Thank

To those who cleared up my confusion! I hadn't considerd plasma.

Paris is ok now.

[Anonymous Coward]

Ahh sod it!

If you go shooting with a bow you would loose a few arrows.

unless soemone shouts fast!

et tu boffin?

[Anonymous Coward]

RE: RE: Terminology

"I think you'll find a Gauss gun is a different type of gun again. ;~)"

*Sigh*

Indeed but Gauss is the standard unit for magnetic flux density.

So I could say "They gave that pellet a good Gaussing to send it on its way"

Although Kenneth Williams would have said it better.

[Solomon Grundy]

Trajectory

Did anyone else notice that the first shot of the projectile shows it nosing downward, then in the next shot it's flat, then moves to nosing down again?

How did they do that? How can the projectile change orientation while in flight?

[Richard Tobin]

Ten megajoules? Peanuts.

My electric fire uses that in an hour - it's only 3kWh.

[John Cobb]

Click Click

Wonder how hardened they are against EMP.

Just imagine if they aren't, and no conventional guns are aboard.

Floating target?

[DZ-Jay]

I claim prior art

Rail Guns are so... last version.

http://www.us.playstation.com/PS2/Games/Ratchet_and_Clank_Going_Commando/PUGG/weapons.htm

Now, Plasma guns: *those* are cool.

-dZ.

[Anonymous Coward]

great

so the warmongers want to continue to spend ridiculous sums of money for something that has no other application than destruction (please correct me if I am wrong, maybe firing chunks of metal at high velocity actually has a benefit to humanity) if they have to insist on developing means of killing others perhaps they might consider something to prevent them killing their own allies

its not been a good day, can you tell!

[Dave Bell]

It's not that hard to deal with.

All you have to do is build a meson-gun battery on the other side of the planet.

(Yes, I still have my Tukera Lines crew ID card....)

[xjy]

Boom-bang-a-bang

Maybe if they fire the projectile at the inhouse nuclear plant they obviously use to power the thing they could kill two turkeys with one bolt.And this is going on at the same time as civilians are being chivvied about saving power...

Just imagine if the resources squandered here were put to intelligent people-friendly use, and the "scientists" deployed to create and prioritize such beneficial usages for deprived areas in both rich and poor countries. It isn't hard to do.

[Anonymous Coward]

@great By Anonymous Coward

Well, flying chunks of metal have been known to clean up the gene pool

[ImaGnuber]

RE: great

Absolutely no argument regarding content and attitude but until we all learn to get along (human nature undergoes substantial change) I want to be on the side that owns the latest model Death Machine.

Cool video. Wish they'd used a pumpkin for a target.

Paris because I loved the video and wished they'd used a pumpkin.

[Ed]

@AC

"please correct me if I am wrong, maybe firing chunks of metal at high velocity actually has a benefit to humanity"

Railguns are awesome. There you go.

[Franklin]

Technology marches on...

"Now DARPA have got it to work about as well as the conventional alternative, in a demo. Nothing to see here, move along ..."

The same could have been said for the first gunpowder weapons. Early bombard cannon were a lot more dangerous to their crews than to castle walls, and in any event were scarcely more effective than trebuchet...but people kept developing them anyway, eh?

We're approaching the end of what's possible with chemical explosive weapons, just as the trebuchet was approaching the end of what was possible with muscle, gravity, or spring powered weapons...and new technologies are the way forward. For, y'know, killing people dramatically.

In any event, I want one for my next party...

[Graham Dawson]

@ac

be quiet and enjoy the fireworks ya feckin hippy.

[Tyler]

@great

It could have space exploration uses. Attach a larger one to the ISS, have it charge an enormous battery for a day then shoot a probe put past our solar system. I dunno any of the sciences behind these kinds of things, but I imagine with enough power and space vaccum you could reach insane speeds.

[Anonymous Coward]

Verb

Perhaps the verb for this type of weapon should be "discharge". It works for both the electrical side of things and for the act of expelling the projectile itself.

[Anony Mous]

Possible uses for hummanity:

1.) Launching satellites into Earth orbit.

2.) Launching probes from the Moon into deep space.

3.) Modifying the tech -- turning it into a train system.

4.) Modifying the tech -- turning it into an aircraft launching system.

5.) Modifying the tech -- turning it into an amusement park ride.

6.) Disposing of violent dictators from 200 miles away.

7.) Just for the hell of it. :)

[Anonymous Coward]

Sure, this is cool...

...but the slow reload time means that you'll be toast in 1v1 if the other guy has the red armor and a rocket launcher.

[Chris G]

Intelligent people friendly ....

uses could include using this technology to accelerate hippies into the surface of the sun, thus removing their veggie, methane producing arses from the planet and benefiting humanity with less greenhouse gases. Anyway, one of the reasons that humans are what we are is because of our ability to create ever newer and cooler weapons.

Discharging is definitely the word.

[Chris]

Space use

Problem with using something like this in space is the whole newtonian physics. You know, the pesky "Every action has an equal and opposite reactiong" bit? You shoot something with that much force, and you have to have a way to compensate against all that force pushing you out of orbit.

[Amber]

Imagine...

One of those things on the George Washington, or the Nimitz, or even the Enterprise. Any carrier would have the ability to create to power to fire one of those things, I think. Or, they will once out wonderful scientists fix the bugs with it.

Almost makes me wish I was an FC rather than an IT. Almost.

[heystoopid]

Nice

Nice a modern variant of the old infamous Paris gun from WW1 !

Sadly the EMP effect from shooting the beast would stand out like a very bright beacon to any passing satellite or long range scanning EMR/AWAC's plane fitted with a standard MAD from the usual ASW aircraft traversing the battlefield every time it fires , oh so sorry we unleashed another battlefield area nuke what a pity !

[Anonymous Coward]

@heystoopid

There are two basic scenarios - defensive fire and offensive fire. In the defensive case, the enemy already knows where you are ... umm, that's why you're shooting, OK? In the offensive case, the enemy is about to know where you are ... and they sure ain't goin' to need a satellite to figure it out.

Remaining undetected is a nice idea, but quite impracticable once the shooting starts even with current weapons. You may even have heard of 'manoeuvres'? They're necessary on account of it being a bad idea to stay still once you've announced your presence with an opening shot!

[David Willis]

Big Railgun..

Ok.. so mission plan..

1. Choose enemy target..(say a T72)

2. Drive 30 tonne articulated lorry up to target, reverse to face target and open rear doors.

3. Tap on turret of tank, ask them were the nearest electrical socket is, and ask them if they mind waiting for gun to charge up.

4. Plug in, charge up and fire...

The above can be repeated 4 x then back to base for a new barrel..

Hmm.. and the man portable feasability of this is ??

PS built something similar out of solenoids at high school. It could fire a six inch nail through 3 telephone directories (the old thick ones not the new thin ones). Never suffered barrel wear (did suffer appauling jam problems). But at least it was men portable (one for the solenoid assembly one for the batteries)

[Anonymous Coward]

@Great by AC

There's a clear and present benefit to humanity.

The secret to world peace is more weapons rather than fewer. Once it reaches the stage that everyone has a half-dozen nuclear tipped ICBMs buried in silos in their backyards, you'd better believe that we're all gonna get along just fine. Either that or the cockroaches are one day going to become intelligent enough that they're gonna wonder what became of all the monkey kind of people who used to spray stuff on their distant ancestors.

Either scenario results in world peace.

// Paris knows all about world peace.

[Tawakalna]

why slugs and not snails?

presumably the snail's shell creates extra drag as compared to the more streamlined shape of the slug?

I'll get me shell....erm, coat.

[Death_Ninja]

Peace

Hmmm funny you should say that AC, I too have thought the best hope for peace in this world is to divide up the military firepower equally amongst nations.

My own personal idea was to do this at an individual level.... I have always fancied my very own SS-18 as the ultimate deterrent to the local kids who like to throw stones at my car....

[Anonymous Coward]

@ David Willis

You must have gone to a good school!

[Stuart Van Onselen]

Lots of power...

Actually, Richard Tobin has it right. The gun does not use a lot of energy. It delivers a modest amount of energy really-really-really quickly.

You don't need a nuke power-plant to run it, a decent-sized coal/oil/gas-fired electric generator would do. But bigger generators do mean faster recycle times. The generator runs for a few second/minutes/hours to charge a bank of capacitors. Then the capacitors release all that energy in micro-seconds.

The tricky part is getting capacitors big enough. That is on top of all the other problems, such as barrel life, and terminal guidance. (No-one has yet come up with an electronic guidance computer that can survive the hundreds or thousands of G's of acceleration involved.)

In short, it makes for way-cool demos, but railgun technology needs a lot of work before it becomes feasible for the battlefield. But at least it's closer to ready than offensive lasers are!

[Anonymous Coward]

Tompions

Tompions generally come in three variants.

Solid, watertight and heavy. Used at all normal times to protect the gun from weather and stray birds nests.

Ceremonial. Pretty and just slid over the first sort.

Note that attempting to fire the weapon through either of the above will be disastrous.

Thirdly a rubber cover which is used instead of the first type when you anticipate having to fire at short notice. "War" tompion. Not removed before firing.

The sort of "other weapon systems you are being coy about will include Polaris/Trident then?

Jim

================================================

"The tompion (muzzle cover) that you see on ships in harbour is a ceremonial version - usually polished brass or chromed steel - while tompions used at sea are quite different. They're not removed "just before firing" but rather for a given state of readiness. Given the barrel interior withstands many hot blasts of propellant as well as a projectile scraping past it's rifling, you should be able to see that a bit of salt water isn't really much to worry about. But barrels get cleaned anyway, to maximise their life and minimise cost to the taxpayer. If it comes to it, the round can be fired straight through the tompion, anyway.

Other weapon systems (I won't go into details) use weatherproof membranes which are punctured on firing - it's quite harmless as far as the ordnance is concerned."

[Vladimir Plouzhnikov]

Oh and remind me...

... what exactly were those bits and pieces flying behind the projectile slug? Penetration aids?

[Viktor]

@Vladimir Plouzhnikov

Probably pieces of the rails.

Paris because she knows everything about bits and pieces.

[Jeff Dickey]

Bits and pieces

@Vladimir...

Isn't it obvious? Those tiny, overheated fragments were the remains of the budget busted to build the BFG in the first place!

[Dalen]

IMPRESSIVE

Now they have to come up with a Quad.

[Tim]

Nice...

It looks extremely cool. Though is a long way from being Battlefield ready. It seems more likely it'll be used for 1 off's like shooting down missiles (or satellites) rather than tanks if it can shoot 4 times, and will take 64megajoules a shot. I guess it won't quite be up to machine gun fire rates.