Navy Test Fires 10 Megajoule Railgun (Holy Cow)

I think this technology could also be used as a cheap way to launch payloads into Orbit with out expensive rockets.

The shockwave distortion and the air ionization looks way cool.

But the projectile goes right through, still at super-sonic speed, and quite unscathed. This can be neither efficient nor desired. Those megajoules are useless if they don’t end up in the target. (What DID stop the projectile then?)

May we assume the ‘real’ impact didn’t look as impressive as this nicely glowing fireball? (Have they hidden explosives in the target again, like when someone needed to round up funding for that super-laser weapon?) I have trouble understanding how this can happen without vaporizing the projectile unless the target itself was weak and combustible. What do you demonstrate by punching a pinhole through plywood, instead of, say, vaporizing armor plate?

“Sometime between 2020 and 2025”. Yeah, right. And moon cities. The current state of the art appears to be that they’re happy to announce the rails don’t blow apart and the bore even survives multiple shots.

1% real research (I do admit, this part IS impressive), and 99% trying to wow the brass.

Dang! 1 shot every 6 seconds with that much power? Can we say overkill?

To Lab_Rat: I don’t know for sure, but wouldn’t the electromagnetic stuff screw up the rocket’s circutry?

Hey Yocto, considering the target has the Navy logo on it, I’m inclined to think these pictures are for press releases. I’m sure they’ll save the less glamorous armor plate targets for the real tests. If you’re not impressed by rail gun technology, then you’re not paying attention. By the way, there’s no bore. The projectile sits in magnetic rails. Get it? “RAIL” gun? It doesn’t shoot rails. It’s not a mega nail-gun. Inform yourself before you go hatin’, please.

i think, it could be used to hit the highly armored ammunition bunker in ships,
and destroy them with one precision shot, if all the ammonution explodes inside.

Rail guns have been in development for about 90 years (look it up). The theory is sound because it’s so brilliantly simple, and there have been working prototypes for decades (at least since the Star Wars program of the 80’s) capable of destroying static ballistic missiles casings, but requiring obscene amounts of power and track lengths, making them at the time very impractical. Now we have much more efficient power systems in place, similar to what power the airborne laser system the USAF is currently testing on the YAB-1 modified Boeing 747. All that’s needed for a projectile is a sufficiently strong material and aerodynamic shape. Size is mostly irrelevant, so long as it has the mass, and it will create a surprisingly big bang as mass is converted into energy in a fraction of a second. Lob a big enough mass at a high enough speed, and you can simulate a nuclear explosion without all the messy radioactive fallout afterwards.

Hey alnoga, read again. I said I AM impressed. Just not by the other 99% of fluffed up military talk around it.

Yeah, exactly. That’s the purpose of military press releases. To show some flashy pictures and to get the voter’s approval for the budget. Who cares about realistic presentations that accurately demonstrate what this project is promising to achieve.

By the way, their own briefing documents talk about “bore design” and predicted “bore life” (apparently assuming the simplified definition here that a bore is what guides the projectile).

Impresive thins are they doing those days… USA is at least 20 years aheah of everybody else.

i saw that metal steel clip on youtube .. that is some serius gun power but this one is also great

This article explains the flames, projectile, target and the bore/rail.
http://www.signonsandiego.com/news/military/20080202-9999-1n2gun.html

Here is the Navy’s article too.
http://www.navy.mil/search/display.asp?story_id=34718

Hold on… Yocto, are you dissatisfied with the amount of force put into a projectile disregarding the accuracy?

First of all, accuracy with a rail gun would be finite and limited to the human/computer program controlling it. This is physics in it’s most unadulterated form.

Secondly, I would imagine you are thinking of a weapon in which the projectile tumbles, causing maximum damage. However, try shooting such a projectile at a wall – what do you get? A shit load of cinder block debre and one healthy target. If the navy is able to eliminate a target with barriers, imagine the implications. All a person would need to know is time / place. Move navy into position 200 miles away, and deploy aluminum shards. Done.

Interesting. They have a railgun, and they shoot it through a sand-filled tin can! Honestly, there must be 1000 better ways to demonstrate a railgun than to create incandescent sand.

Considering that 10 MJ is equivalent to 2.4 kg of conventional TNT, there should have been nothing left of that target. This one certainly sets a milestone in railgun engineering, but tactically speaking… Expect a LOT of money (that you could spend otherwise) going into it until we might receive a return in form of a practicable and reliable weapon system.

to 2nd Anonymous: I don’t know, either way, it’s a highly specialized technology, and I just don’t find it very promising (and so far, it’s just that, a promise for future technology) in actual combat, when compared to already existing (and already paid for) weapon systems.

This is fantastic and not just for use with weapon systems. If they are able to achieve 13K mph in the future, escape velocity ( about 18K mph) could be next. This could be a boon for satilites

The problem with using this for satellites is the fact that – oh, it uses a /phenomenal/ amount of electromagnetism. And class, what happens when you create a huge (E)lectro(M)agnetic(P)ulse around electronic equipment?

Ooops.

Thank you srilyk, thats what I was talking about. That’s why I didn’t think a rail gun would work for that kind of thing.

Guys, ok, no satellites… but what about other stuff to send, let’s say, to a space station? Or to the moon or mars… I mean, most of the times, we need to send other goods along with missions, satellites and space stations (not only electronic equipment). This could be a cheap way to reduce costs of rockets, by reducing the quantity of material that needs to be sent “up”…

(ok, the military, as anyone could expect, need funds and are presenting this with this objective, but still, it could be used for many other things…. ).

Let’s wait this 15-20 years and see…… (buahhaahaha)

Of course, the obvious answer to the megajoules question is that it’s meant to be a more powerful armor piercing projectile. What good is an armored bunker if your adversary has one of these? You may be able to run, but there’s no such thing as hiding behind steel and concrete.

Use for orbital resupply has merit; some. It could not be used for electronics in most forms nor machinery; remember too that whatever you shoot has to survive unbelievable G forces when its accelerated in addition to the stresses and electrical issues from the magnetic fields. …But you could shoot strong cans filled with commodities and robust machine bits. So pick an orbit where a UOV can retrieve the cans and bring them to the station easily and use the gun to fill that orbit with cans of hydrogen, oxygen, some foods, a few parts well packed and some experiments or their supplies could be packed in too; stuff that can survive the trip. Then have the UOV shuttle them from that orbit to the station. Maybe if the cans could be made to survive multiple shots and re-entries they could be reused too. As cool as it sounds to do this it might not be the best choice though: A large (and very long barreled) cold-gas gun could launch cheaper cans of equal or greater internal volume and do it while imparting less G-forces on the payload as well as little in the way of magnetic issues. – With either gun, another consideration would be to send tough big simple Tinker-toys or Legos, to use as base structure for more space station, instead of building uber-light-weight, super-engineered, fold-up, multi-functional trusses and structures. Send all kinds of cheap dumb bits up in these big bullets and only use expensive launch technology for the habitats, gear and people. …Then use all that stuff to just build the damned space elevator.

The images of the railgun with flames in them following the projectile are not what they have been claimed. These are shots from a conventional gun being used to develop the best ballistic shape for the railgun round. There are many videos of the projectiles being placed in their polymer sabots in pre-fire condition. The gun itself will need a sabot that will withstand the friction of moving beyond Mach 7. Polymer is not capable of retaining its shape at that velocity, friction will inherently cause it liquify and reduce velocity. Many have also wondered why go to a railgun platform? In combat you are also being shot at so you need to reduce the amount of volatile material you carry aboard ship. The most volatile substance aboard ship is the propellant stored in the magazines to fire the guns, rockets and missiles. Every amount you can remove from the ship makes it less likely to have a repeat of the HMS Hood.

The images of the railgun with flames in them following the projectile are not what they have been claimed. These are shots from a conventional gun being used to develop the best ballistic shape for the railgun round. There are many videos of the projectiles being placed in their polymer sabots in pre-fire condition. The gun itself will need a sabot that will withstand the friction of moving beyond Mach 7. Polymer is not capable of retaining its shape at that velocity, friction will inherently cause it liquify and reduce velocity. Many have also wondered why go to a railgun platform? In combat you are also being shot at so you need to reduce the amount of volatile material you carry aboard ship. The most volatile substance aboard ship is the propellant stored in the magazines to fire the guns, rockets and missiles. Every amount you can remove from the ship makes it less likely to have a repeat of the HMS Hood.

Thanks for sharing. Very interesting.

the flame from the ammunition is actually plasma gas, the bullet was supercharged during the contact with the magnetic field, and thus when the bullet impacted, most of the charges escaped as plasma, it is not a conventional projectile.