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Navy tests rail gun

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Re: Navy tests rail gun

#51

Post by JoeAltmaier »

harywilke wrote: post #47

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. the…

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.

Re: Navy tests rail gun

#53

Post by [deleted] »

fasteddie31003 wrote: post #46

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.

[deleted]

Re: Navy tests rail gun

#54

Post by pistle »

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?

Re: Navy tests rail gun

#55

Post by JoeAltmaier »

lmg643 wrote: post #44
edgarallenbro wrote: post #24

$25,000 for a single projectile is "affordable"? Why do I feel like I'm living in a madhouse?

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.

The projectile is a marvel of materials engineering. It has to accelerate to Mach 7 in a few feet, survive friction with the surrounding air for 100 miles, and have enough remaining core to deliver sufficient kinetic energy to be worthwhile.

Its definitely not just a chunk of barstock milled to a point.

Re: Navy tests rail gun

#56

Post by PavlovsCat »

JoeAltmaier wrote: post #33
edgarallenbro wrote: post #24

$25,000 for a single projectile is "affordable"? Why do I feel like I'm living in a madhouse?

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.

Increasing the costs for other tax payers does not make it cheaper though. Furthermore, the weapons cost the same wether they are fired at an approaching tank, into the air, at a bunch of baby seals, or not ever. It's not like weapon peddlers buy back the unused stuff at full price, do they.

Re: Navy tests rail gun

#57

Post by yread »

sjtrny wrote: post #27

This is not news. This rail gun tech has been around for years. Here is a video posted in 2012 which shows the exact same gun: http://youtube.com/watch?v=eC2hu9bildA

Interesting it's exactly the same images. Why is this news?

Re: Navy tests rail gun

#58

Post by dm2 »

icegreentea wrote: post #13
dm2 wrote: post #6

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 wo…

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…

The Wikipedia page says the engines are this kind and only produce 9MW: http://www.mtu-online.com/mtu/products/engine-program/diesel...

But I see what you are saying, that seems like plenty, I had always assume that it would take a huge amount of energy (I know pretty much nothing about electricity).

Re: Navy tests rail gun

#59

Post by pmorici »

edgarallenbro wrote: post #24

$25,000 for a single projectile is "affordable"? Why do I feel like I'm living in a madhouse?

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...

Re: Navy tests rail gun

#60

Post by mkr-hn »

fasteddie31003 wrote: post #46

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.

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?
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