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Bad ass, thy name is railgun

The U.S. Navy has been working on rail guns to replace traditional large bore weapons aboard ships. The first of two new prototypes was delivered on February 6 (the second is due in April) and is now firing projectiles. The USN recently tested a 32-megajoule prototype railgun demonstrator that was built by BAE. The weapon was fired six times in a single week according to officials.
 
The weapon fired non-aerodynamic test rounds that are designed to slow down quickly. Tom Boucher, the Navy’s railgun test director at Naval Surface Warfare Center Dahlgren, VA added, "But eventually the program intends to fire a very low-drag, high-speed projectile.”
 
The finished version of the railgun will eventually be able to fire a single projectile up to 220 nautical miles.
 

 
“The new guns are a significant step beyond the laboratory-style launchers, which are big, bulky, not anything you would put on a Navy ship,” Roger Ellis, railgun program manager, said.
 
“The new industry prototypes are a step beyond and much closer to the fit and form that we might want to put on a ship some day — lighter weight, able to train and elevate.”
 
The Navy hopes to eventually place the railguns on DDG-1000 Zumwalt-class destroyers. However, the railguns could find their way on other classes of ships as well since the technology is scalable.
 
The railgun is being looked at for operational capability between 2020 and 2025, but the Navy is looking for ways to reduce the wait. 

Source: Navy Times



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Holy crap dude
By mitchrj on 2/29/2012 9:59:43 AM , Rating: 2
Can you seriously proofread this stuff?
It's like a writing assignment from a kid in an elementary school English as a Second Language program.




RE: Holy crap dude
By crimsonson on 2/29/2012 10:05:34 AM , Rating: 1
I assume you are new here. This issue has plagued DT for years. It is pretty sad. I assume they consider themselves professional writers.... or at least writers.

Second, stop ESL would write better than this - or least would make better effort.


RE: Holy crap dude
By Methusela on 2/29/12, Rating: 0
RE: Holy crap dude
By Methusela on 2/29/12, Rating: -1
RE: Holy crap dude
By Kyuu on 2/29/2012 11:12:49 AM , Rating: 3
WTF are you people even talking about. What's the issue with the article?


RE: Holy crap dude
By Methusela on 2/29/2012 1:35:50 PM , Rating: 5
It was due to several grammatical errors, a spelling error, erroneous punctuation, and a sentence logic error. All have been edited now, but that's besides the point.


RE: Holy crap dude
By rcc on 2/29/2012 6:55:43 PM , Rating: 2
that would be "beside the point".


RE: Holy crap dude
By Methusela on 2/29/2012 11:58:15 PM , Rating: 1
Nice try. In this expression, either beside or besides are correct, depending on the context. In this case, besides works because it means "apart from" the point I was making; my original point regarding the errors was separate from the statement of said errors' correction. For reference, see:

http://www.usingenglish.com/articles/beside-beside...

Also, punctuation always goes "inside the quotes."


RE: Holy crap dude
By tng on 3/1/2012 11:10:04 AM , Rating: 3
What I find interesting is the fact some people out there can't seemingly get past grammar issues, while there is so much more to the article to discuss. Is the grammar issues all that you got from the article?

The level at which you describe the "beside the point" comment shows that you need more in your life.


RE: Holy crap dude
By Methusela on 3/1/2012 2:42:09 PM , Rating: 2
You're missing the point: as originally constituted, the article was not comprehensible. Poor grammar, omitted punctuation, and spelling errors can change meanings or obscure them entirely. Didn't you learn that in middle school?

Also, I was expecting the typical "get a life" response much sooner, but thanks for that classy response.


RE: Holy crap dude
By tng on 3/1/2012 6:13:06 PM , Rating: 2
quote:
Also, I was expecting the typical "get a life" response much sooner, but thanks for that classy response.
You are very welcome.

As someone who has to translate technical documents, I get it, but I question the need to go on about grammar when the subject of the article is completely ignored. Yes I have read some atrocious grammar here, but always understood the meaning, maybe it is just you.


RE: Holy crap dude
By Gondor on 2/29/2012 11:27:07 AM , Rating: 2
The article looks fine to me ?!

There is indeed an automated downrating thingy thugh, using certain words will result in -1 base value (1 instead of 2).


RE: Holy crap dude
By mmatis on 2/29/2012 11:51:26 AM , Rating: 2
Actually, it's FAR simpler than that. The page merely reads what browser you are using, and sets the base score from that...


RE: Holy crap dude
By HrilL on 2/29/2012 2:41:57 PM , Rating: 5
So he must be using safari?


RE: Holy crap dude
By lightfoot on 2/29/2012 5:13:15 PM , Rating: 2
You also get auto-downrated for "feeding the trolls." It works by downrating any reply to a comment that is its self rated -1.

But there is a reason that the grammar-nazi posts always get downrated... they simply aren't worth reading. It's nothing sinsiter, just the truth.


RE: Holy crap dude
By ianweck on 2/29/2012 11:12:08 AM , Rating: 1
quote:
I don't understand why the DT writers/editors continually down-rate criticisms of their writing, as this is what most likely happened to the two previous posts.


Maybe people are just tired of reading worn out comments about proofreading?


RE: Holy crap dude
By AEvangel on 2/29/2012 1:04:51 PM , Rating: 1
It's due to the language used in the subject line.


RE: Holy crap dude
By Methusela on 3/1/2012 12:03:58 AM , Rating: 2
We've hit ludicrous speed! Here's another GLARING error in the very first sentence of a new article:

http://www.dailytech.com/article.aspx?newsid=24130

For posterity's sake, in case it's fixed by the time you read this post, the very first sentence of the article reads:

quote:
What black and shiny and as big as your hand?


It's not possible to miss that if you proofread your article before submitting it.


RE: Holy crap dude
By mitchrj on 2/29/2012 6:03:09 PM , Rating: 2
For those of you downranking into oblivion, you obviously did not read the article as originally published.
It had sentences that were completely and totally unstructured.

Glaring, massive faults that showed a complete and total lack of basic editorial standards.

If you guys don't want to see people complaining about this kind of stuff, then hold your Dailytech writers to higher standards.


For comparison
By Solandri on 2/29/2012 12:34:20 PM , Rating: 5
For those who don't know, a Joule is a unit of energy, abbreviated J.

20 J - airgun
500 J - 9mm pistol
2 kJ - 5.62mm NATO round
15 kJ - .50 caliber round
22 MJ - M829A1 round (M1A2 tank sabot round)
32 MJ - test shot from this railgun
550 MJ - 16" gun on Iowa-class battleship

This is the energy of the traveling round, not the explosive charge. 1 kg of TNT has about 4.2 MJ of explosive energy.

So in terms of munitions at a ship-level, 32 MJ is really small potatoes. But the hope with this is to reduce the amount of space needed to store ammo (a lot of the ammo is actually propellant), and to eliminate the risk of catastrophic explosion if the magazine (where the ammo is stored) is hit. Railgun ammo is just metal slugs - no propellant or explosives. It does its damage purely through energy from velocity, not an explosive charge.

Long-term, railguns along with gas guns look to be our best chance for launching payloads into space cheaply. Delicate payloads like people would still need to be conveyed using rockets or rocket planes. But most of the mass associated with spaceflight (fuel, electronics, food and water, etc.) can survive high accelerations and thus could be "shot" into orbit at tremendous fuel savings over conventional rockets (which need to burn fuel to lift fuel - 95% to 98% of the mass of a rocket is fuel).




RE: For comparison
By bobsmith1492 on 2/29/2012 12:45:56 PM , Rating: 2
Kinetic energy is 0.5*m*v^2, so I would assume a 16" gun shell simply has a whole lot more mass than one of these metal slugs.

Wiki says "They fire projectiles weighing from 1,900 to 2,700 pounds (850 to 1,200 kg) at a maximum speed of 2,960 ft/s (820 m/s)..."

It looks like these railgun slugs weigh no more than 40lb since that guy put one in by hand. So, a 16" shell has a 60x advantage in mass, meaning this railgun shot would have about 2x the velocity...


RE: For comparison
By lightfoot on 2/29/2012 5:29:05 PM , Rating: 2
quote:
So, a 16" shell has a 60x advantage in mass, meaning this railgun shot would have about 2x the velocity...

I think you mean 8 times the velocity - 8 squared is 64 which would offset the 60 times weight advantage.


RE: For comparison
By bobsmith1492 on 2/29/2012 7:14:21 PM , Rating: 2
It's 550 vs 32 MJ though.


RE: For comparison
By boboberg on 3/11/2012 4:59:13 AM , Rating: 2
But Iowa class guns can't shoot projectiles 220 nautical miles. Mark Montgomery NYC, NY boboberg@nyc.rr.com


RE: For comparison
By Reclaimer77 on 2/29/2012 5:50:16 PM , Rating: 2
That was a test slug. Shaped and weighed so that it didn't slam past every barrier and exist the test range and end up in someone's living room two cities away.

A real rail-gun "warshot" slug would be far FAR more deadly in shape and weight.

quote:
Wiki says "They fire projectiles weighing from 1,900 to 2,700 pounds (850 to 1,200 kg) at a maximum speed of 2,960 ft/s (820 m/s)..."


That's for testing purposes. The real ship-based railguns will have muzzle velocities of 5,000mph+.

Sorry but there's simply no comparison in the destructive potential between a rail and gun shell.


RE: For comparison
By bobsmith1492 on 2/29/2012 7:15:35 PM , Rating: 2
The Wiki quote was for the 16" standard shell, not the rail slug.


RE: For comparison
By waynet2 on 3/4/2012 11:14:32 AM , Rating: 2
quote:
That's for testing purposes. The real ship-based railguns will have muzzle velocities of 5,000mph+.


I believe you meant 5000fps+, not 5000mph+.


RE: For comparison
By jithvk on 3/1/2012 1:07:58 AM , Rating: 2
Kudos for spending time to explain the details.. I would say your comment is more explanatory than the article.

The article is like a BAE brochure and your comment is like a documentary.. :)


RE: For comparison
By MZperX on 3/2/2012 12:54:07 PM , Rating: 2
Good post Solandri but there is no such thing as a 5.62mm NATO round (that I know of). The existing NATO small arms rounds are 5.56mm and 7.62mm (5.56x45 and 7.62x51). I assume you meant the 7.62mm one and this was just a typo. Cheers!


RE: For comparison
By vic5014 on 3/5/2012 12:56:06 AM , Rating: 2
eliminating the need to store chemical propellant and explosive ammunition should makes ships safer, but what about the fact this thing uses massive amounts of current? I was talking the video with a buddy of mine who used to work as an electrical engineer and he was all "enormous amounts of current on a metal box floating on salt water. gee, wonder what could possibly go wrong?" at least when something does happen, there won't be to worry about treating the wounded.


Fire?
By kwrzesien on 2/29/2012 10:33:12 AM , Rating: 2
So what's with all the fire at launch?




RE: Fire?
By Brandon Hill (blog) on 2/29/2012 10:34:19 AM , Rating: 2
Check the embedded video.


RE: Fire?
By Kyuu on 2/29/2012 11:10:47 AM , Rating: 2
The embedded video shows the fire at launch, but doesn't explain it.


RE: Fire?
By aegisofrime on 2/29/2012 11:18:25 AM , Rating: 2
Took a look at the comments and here's what someone says:

@ronindebeatrice yeah loud explosion and fire are caused by? friction of the missile with the air, which is then heated and turned into plasma

Mandrak789 27 minutes ago

Not sure if that's correct or not. But it sounds plausible.


RE: Fire?
By geddarkstorm on 2/29/2012 11:58:41 AM , Rating: 3
They are firing non-aerodynamic "bricks", basically, at extreme velocities well above terminal. It's basically like the thing is entering the atmosphere from space; only in the much denser sea surface atmosphere rather than gradually falling in from the thin stratosphere.


RE: Fire?
By MrBlastman on 2/29/2012 12:52:09 PM , Rating: 2
Well, I think I read somewhere in the past that they are using a chemical charge to initiate the movement of the projectile down the rail assembly, at least in the prototype. The finished weapon will not. With that said, you have to consider just how much energy 32 MegaJoules is... To make sense of it, we can approximate it to be about 15 sticks of TNT going off... to propel a tiny projectile (okay, tiny is relative, here we are talking about a 40 lb object when the project is completed).

That's a _lot_ of energy for such a small object. So, where is it going to go? Well, I'm sure the gun isn't perfectly efficient, so that energy being emitted... has to go somewhere, right? I think a little plasma from the energy converting into waste heat is to be expected. It can't all go into that projectile, right? Perfect efficiency is basically impossible--soo, the excess has to be expelled somehow. There are two choices... let the weapon itself bear the excess (thus stressing the frame) or instead, allow it to be converted into waste energy in the form of both sound, heat and electromagnetic energy.

The age of the Battleship... appears to be returning. 200 miles of range... imagine that.


RE: Fire?
By DennisB on 3/1/2012 2:03:33 PM , Rating: 2
You are misunderstanding here. The given number is the pure kinetic energy on leaving the barrel minus all inefficiencies.
For a normal laser, for example, the beam energy is 10% of what goes into the weapon system. Here the exact number is obviously not given for the whole thing. What happens after leaving the barrel is just ballistics & hydro/aerodynamics. The recoil stress of the weapon is already given. ;)


RE: Fire?
By vic5014 on 3/5/2012 4:29:15 PM , Rating: 2
Unless I'm mistaken, there's no chemical charge involved. railguns are electromagnetic. they use huge amounts of current to launch objects.


RE: Fire?
By vic5014 on 3/5/2012 4:37:22 PM , Rating: 2
that's one of the benefits of using railguns on a warship. you wouldn't believe how many incidents there have been where ammunition or its gunpowder propellant just ignited. throw in the fact that there's always the chance of enemy fire hitting the ammo room, and you've got a major hazard on board warships. The famous fire on the USS Forrestal, the worst in US Navy history, started because a rocket accidentally went off and ignited some jet fuel, which then set off a few bombs, incidentally almost killing John McCain. Yes, that John McCain. seriously, look it up.


I...
By rpsgc on 2/29/2012 9:51:55 AM , Rating: 3
...want one.




RE: I...
By chmilz on 2/29/2012 10:36:27 AM , Rating: 2
Turret mount. Auto-target algorithm that takes out bad drivers and unroadworthy cars.


"I modded down, down, down, and the flames went higher." -- Sven Olsen

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