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Navy tests rail gun

57 points| zafka | 12 years ago |news.yahoo.com

100 comments

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[+] awda|12 years ago|reply
Have they fixed the problem where the gun destroys itself after three shots? (Edit: downvoters: this is a serious question. This is a (historical?) known problem with railguns.[0])

[0]: https://en.wikipedia.org/wiki/Railgun#Considerations

[+] HCIdivision17|12 years ago|reply
I'm not sure who would downvote that: the amperage is simply staggering! That, and the railgun project has been around for years, with the self-destruct problem being one of the more obvious issues with the idea.

Bludino notes [0] a Popular Mechanics article that quote ls 3MA, with a plan to go to 6MA!

[0] https://news.ycombinator.com/item?id=7553163

[+] JackFr|12 years ago|reply
The first operational beam weapons and rail guns really bring out in stark contrast that all a modern weapon system is, is the ability to reasonably safely store potential energy 'here' and accurately release it 'there', with hopefully catastrophic consequences.

What railguns and beam weapons do, is weaponize nuclear reactors and gas turbines, reducing the need for propellants and explosives. While it's unlikely that this will allow the aircraft carrier to regain the place it once held, it seems likely in the future that massive power generation capability will become more and more important.

[+] edgarallenbro|12 years ago|reply
$25,000 for a single projectile is "affordable"?

Why do I feel like I'm living in a madhouse?

[+] JoeAltmaier|12 years ago|reply
A single-use anti-tank weapon costs $50,000, and worth every penny if you're the infantryman and the tank is heading toward you. Its dirt cheap at the cost, considering the price of a tank.

Same for the railgun. They are shooting at million-dollar targets.

[+] pmorici|12 years ago|reply
When they said that my immediate thought was, yeah a US missile costs millions but is that is representative of the cost of production of a Chinese missile? America's enemies don't buy their missiles from American defense contractors. They already produce electronics a good deal cheaper than the US and that isn't even considering the beltway bandit markup.

Also all the comments saying that this is cheap compared to some other US weapon that is probably similarly overpriced are just silly. These sorts of things are not subject to the kind of competition that normal goods are. Just look at the cost of space flight for companies like SpaceX and Virgin Galactic compared to NASA's which relied on defense contractors until SpaceX came along.

http://www.reuters.com/article/2013/09/27/us-turkey-china-de...

[+] aet|12 years ago|reply
1 Tomahawk missile is approximately $500k (and up)
[+] mkr-hn|12 years ago|reply
$25,000 to tear another ship apart at 7 times the speed of sound is a bargain.
[+] PavlovsCat|12 years ago|reply
Well, transfering money from tax payers into private hands is a lucrative business. Don't attribute insanity to what cold malice explains.
[+] allworknoplay|12 years ago|reply
Because you are. I'm with PavlovsCat -- the relative price comparison is being used to sell extraordinary profits, and otherwise smart people just eat it up.
[+] lmg643|12 years ago|reply
Considering that the rail gun projectile is basically a hunk of metal, $25k does seem really expensive. No gunpowder, nothing. All the work is in the railgun.
[+] chao-|12 years ago|reply
In terms of Defense budgets, that is indeed affordable.

Expenses for Exploration and Production (i.e. upstream oil & gas) operate on similar orders of magnitude.

[+] Qworg|12 years ago|reply
In comparison to a million dollar missile? Yes.
[+] loceng|12 years ago|reply
$2,000 + $23,000 military-industrial complex fee.
[+] fasteddie31003|12 years ago|reply
As a lover of technology and science fiction I love this railgun. But as a taxpayer and pragmatist, I really think it is a waste. I can't see this being as accurate as a guided missile over long ranges, which is the most important thing for modern combat. So that leaves it as a good alternative for short range attacks, which I doubt it will ever be used in combat for.
[+] Retric|12 years ago|reply
Drones don't need pilots which means they don't need pilot training which changes the economics of air-combat. For around ~100k you can build a long rang self guided drone which would be almost useless vs an aircraft carrier or a modern fighter. However, for ~10 billion you can have 100,000 of those suckers and the US does not have anywhere near that many air to air missiles and it's not going to take anywhere near 100k of them to takeout an aircraft carrier.
[+] mkr-hn|12 years ago|reply
I doubt this is an issue with a projectile moving seven times the speed of sound as long as the targeting system is accurate. Even if a warplane could be built to sustain mach 7, how would it turn to avoid the projectile?
[+] dm2|12 years ago|reply
This is the type of ship that it will be mounted on: http://en.wikipedia.org/wiki/Spearhead-class_Joint_High_Spee...

I always assumed it would be put on a Littoral class ship. I'm guessing that the ship is going to be dedicated to this weapon and that's why it wasn't put on a carrier or LCS for testing.

How is it going to be powered? Will it have it's own dedicated nuclear reactor and a huge array of capacitors? I wonder what the time between shots will be.

Here are some nice pictures of the latest version, still amazing that it has become compact enough for a ship in such a short time. http://www.gizmag.com/first-industry-railgun-prototype-launc...

[+] icegreentea|12 years ago|reply
They pretty clearly say that its being put on the Spearhead for testing because it has the space for it. And given all the problems they're having on the LCSs, I think the last they want to do is is to do testing of experimental weapons on it.

As for power, the LM2500 in the Aegis Destroyers put out 20MW. They have 4 of them. This gun puts out 32MJ of muzzle velocity. Assuming 10% efficiency, and you're at 320MJ per shot. If you ran a dedicated LM2500 per gun, that'll get you a shot every 16 seconds.

[+] greedo|12 years ago|reply
The LCS doesn't have the room, nor the power output to use a railgun. The gun "barrel" doesn't take up much room compared to a normal 5" system, but it's the power supply that makes it unsuitable for anything short of a Burke class DDG.
[+] chiph|12 years ago|reply
How is it going to be powered?

If the ship can't provide enough power, they'll probably just put some diesel generators in the cargo area.

[+] alistairSH|12 years ago|reply
It sounds like it will be tested on the Spearhead cargo platform.

I assume as testing progresses, it will end up on other types of ship.

[+] pistle|12 years ago|reply
These are interesting stories. I find mass publicity of war tech interesting. This one has been a long time coming as noted by all the "this is old news" responses.

Who are the intended audiences? What is the intended effect? Warnings to the competition? Psychological effect on economy-draining military efforts in places like N.Korea and Iran? PR/Sales efforts to the military funding and recruitment apparatus?

[+] ogig|12 years ago|reply
This kind of progress saddens me. Who is going to be the target of this weapon? Also think in all the human and material resources involved in creating this, i can't help thinking how many "good actions" could be done instead. How many medical supplies, food and clean water could be distributed with the $$$ used in the development and usage of this.

I'm probably just a naive pacifist, but I think the world would be a better place if Americans stop producing weapons. Especially of this kind.

I appreciate the amazing science behind the nuclear bomb, drones or railguns, but i would rather keep it on the scifi parcel and wish the were never created for real.

Again, I'm probably naive.

[+] chiph|12 years ago|reply
The military would agree with you. After all, they're the ones with the greatest chance of getting killed in a conflict.

The problem is the policy makers tend to regard them as the first option (when they should be the last) for a number of reasons. The first one in my mind is because the number of senators and congressmen with children in the military can probably be counted on less than two hands. None of them would publicly state that they want to see Americans killed in a war, but their actions say different. Dunbar's Number[0] at work.

The other reason is that the US military is amazingly successful. They've fought a two-front war, one against the fifth largest army on the planet, and defeated all opponents. And did it without putting the entire country on a war footing (conscription, entire industries being converted, and so on). So (from the politician's view), why not hand the problem over to someone who can get stuff done?

Lastly - As much as I'd like to believe the world is full of potential friends, if only we could meet and talk -- the reality is that there are a lot of people out there who hate us. Many of them because we killed a relative or friend. But some because we don't live up to their expectations. As weird as that may be. Consequently, a strong means of national defense is required.

[0] http://en.wikipedia.org/wiki/Dunbar's_number

[+] holograham|12 years ago|reply
what is counter intuitive about the defense industry is that the development of new weapons like this (and the other weapons you have mentioned) have actually increased peace in the world. Certainly not the ONLY reason to be fair.

A great book on this is "The Better Angles of Our Nature: Why Violence has Declined" by Stephen Pinker. I recommend any pacifist (really anyone) read this book.

While we hear about the immense destructive power of new weapons, the reality is that they are seldom used. Most of our Defense budget is building an army that no one would dare attack. It is like our nuclear bomb policy -- 100% guaranteed retaliatory strike(s) but no first strike. This project is designed to replace expensive missiles with (relatively) inexpensive inert metal slugs that yield the same capabilities (range, stopping power, etc). This is most definitely a program that would lower costs and increase discretionary funding outside of the military.

[+] malandrew|12 years ago|reply
Interestingly this story makes me wonder whether economic consequences even enter the picture when choosing to engage. I never would have imagined an admiral asking themselves "Is this worth the cost of a $1.5 million missile?" I reckon that it would be a binary decision based on threat alone. Are there any guidelines in the military where the commanding officer is instructed to perform any sort of cost benefits analysis when making the decision to engage a hostile?

Would a dramatically lowered cost greatly increase the likelihood that the navy will be more willing to act as an aggressor?

[+] scottmagdalein|12 years ago|reply
I can't imagine the amount of electricity (even just for a split second) it would take to pull this off.
[+] jzwinck|12 years ago|reply
You don't need to imagine, we can compute it!

Mach 7 is 2382 m/s. 23 pounds is 10.4 kg.

Since k=mv^2: (1/2) * (10.4 kg) * (2382 m/s)^2 = 29504404 Joules.

That's 29.5 MJ, which is 29.5 megawatt-seconds. So it could mean 29.5 megawatts for one second, except of course the rail time is much less than one second. But who cares, let's convert to household units! 29500 kilowatt-seconds is 8.2 kWh. At an average price of US$0.13/kWh, that comes to just $1 worth of electricity to fire a $25000 projectile.

Oh, yeah, the losses. Those are probably 90% or so, so let's say $10. And mark it up a factor of ten because the electricity is on a boat, so $100, and a factor of 50 because it's a weapons system. So ballpark $5000 in electricity TCO to fire the $25000 projectile.

[+] HCIdivision17|12 years ago|reply
If I recall, one of the huge challenges was handling just that. Specifically, I remember something written on it a few years ago that the device was functional, but due to the overwhelming amperage, each shot fused the system up. And now I'll believe it, given that the video shows the casing partially vaporizing as the projectile is exiting.

There's something incredibly shocking about something exploding without traditional explosive chemistry. Just a monumental arc flash (or something - I don't know if it's the same mechanism).

[+] zafka|12 years ago|reply
In the ideal case, the math is pretty simple. The kinetic energy in 1/2MV^2 . (integral from 0 to mach 7) so if you know the weight of the missile...
[+] iliis|12 years ago|reply
Can somebody please add a warning that there's an autoplaying video? It's a bit awkward if your phone suddenly starts talking about guns when your standing in line in a bank :/

Edit: A video tag would be nice in general for mobile users.

[+] probably_wrong|12 years ago|reply
Aren't you supposed to turn off your phone while inside a bank?
[+] harywilke|12 years ago|reply
i wonder about his statement that not a thing in the sky would survive at hit. from the video of it punching through the reinforced concrete walls, it seem that there is very little damage to the wall besides the obvious hole. sort of like the shaolin monk throwing a needle through glass. https://www.youtube.com/watch?v=eW_97D0hLBc but i'd guess this is more a question of what kind of target they are shooting at. they present incoming missiles (small and mobile) and something over 100 miles away (big and stationary?).
[+] JoeAltmaier|12 years ago|reply
Targeting is certainly important and remains to be seen if they're up to it. But Mach 7 means you only have to get a fix on it, and a rough estimate of its speed; the missile will arrive in milliseconds and the target won't have moved very far.

But is there anything in the air that has enough extra parts that it can survive a 10-inch hole through and through, and destruction of everything in between? Certainly not any missile.

[+] havemurci|12 years ago|reply
Would this type of weapon be able to shoot satellites right out of the sky?
[+] netcraft|12 years ago|reply
I have been hearing about rail guns for years - so its a little surprising to me that the projectiles still cost 25k and they don't expect them to be on ships till the end of the decade.
[+] zerohm|12 years ago|reply
So how is the accuracy?

How many shots will it take you to hit a missile 50 miles away? 100 miles? Parallel vs perpendicular path?

[+] clef|12 years ago|reply
A bit like what Babylon 5 called "mass drivers".
[+] mrottenkolber|12 years ago|reply
Being a radical pacifist I aide: I always wanted real rail guns (too much quake).
[+] hawleyal|12 years ago|reply
There is no one to shoot.
[+] JimmaDaRustla|12 years ago|reply
There doesn't need to be anyone to shoot - it is there to prevent those who attempt to be something to be shot at.

Remember, it took one bomb to end WWII.

[+] evli|12 years ago|reply
Metal Gear?