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Navy tests rail gun

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Re: Navy tests rail gun

#91

Post by JackFr »

jug6ernaut wrote: post #66
JackFr wrote: post #48

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…

> While it's unlikely that this will allow the aircraft carrier to regain the place it once held... Care to elaborate on this? I was under the impression aircraft carriers were still our best general purpose military tool? (wartime/peacetime/force projection/ect)

Admittedly, I have no special expertise. My understanding is that while for certain kinds of force projection, they are the only game in town, they are such a rich, fat target, a larger and larger portion of their operation (in terms of manpower, arms and electronics) gets devoted to defending the carrier, and this squeezes out the force projection capability. I believe the cost of production of an aircraft carrier is around $12 billion, and I'm not sure if that includes the ~$1 billion worth of aircraft on board.

Re: Navy tests rail gun

#92

Post by JackFr »

Retric wrote: post #64
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.

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 1…

However, $10 billion is a big number for everyone, including the US and China, although for them its at least possible. It's 150% of Iran's military budget and about 80% of North Korea's entire GDP.

Re: Navy tests rail gun

#93

Post by Retric »

JackFr wrote: post #92
Retric wrote: post #64

Earlier quoted context omitted.

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 1…

However, $10 billion is a big number for everyone, including the US and China, although for them its at least possible. It's 150% of Iran's military budget and about 80% of North Korea's entire GDP.

It's 150% of Iran's military budget in one year. Split that over 10 years and it's 15% of Iran's budget. Granted there would be maintenance costs and it's not 100% automated plus you they would need storage even if there taking off from dirt runways etc. But, they don't exactly need 100,000 to be a solid threat either.

Re: Navy tests rail gun

#94

Post by mrfusion »

jug6ernaut wrote: post #82
HCIdivision17 wrote: post #77

Earlier quoted context omitted.

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

The amperage is not the issue(main issue at least). The way a rail gun works the projectile(or its casing) must make physical and solid contact with the barrel. This is because the electric current actually flows through the projectile from one rail to the other rail[1]. This produces huge amounts of wear on the barrel, making it extremely difficult to maintain the barrel. Both in form and in being able have the proj…

Why couldn't there be small metallic wheels in the barrel making contact with the projectile? Wouldn't that prevent wear?

Re: Navy tests rail gun

#95

Post by holograham »

ogig wrote: post #75

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…

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.

Re: Navy tests rail gun

#96

Post by bunderbunder »

Retric wrote: post #93
JackFr wrote: post #92

Earlier quoted context omitted.

However, $10 billion is a big number for everyone, including the US and China, although for them its at least possible. It's 150% of Iran's military budget and about 80% of North Korea's entire GDP.

It's 150% of Iran's military budget in one year. Split that over 10 years and it's 15% of Iran's budget. Granted there would be maintenance costs and it's not 100% automated plus you they would need storage even if there taking off from dirt runways etc. But, they don't exactly need 100,000 to be a solid threat either.

> But, they don't exactly need 100,000 to be a solid threat either.

At least as of October 1967, 1/25000 of that figure would have sufficed.

Re: Navy tests rail gun

#97

Post by oakwhiz »

Retric wrote: post #64
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.

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 1…

>US does not have anywhere near that many air to air missiles

That is true, however the US also possesses a large number of anti-aircraft guns, with plenty of bullets. :-)

Re: Navy tests rail gun

#98

Post by awda »

mrfusion wrote: post #94
jug6ernaut wrote: post #82

Earlier quoted context omitted.

The amperage is not the issue(main issue at least). The way a rail gun works the projectile(or its casing) must make physical and solid contact with the barrel. This is because the electric current actually flows through the projectile from one rail to the other rail[1]. This produces huge amounts of wear on the barrel, making it extremely difficult to maintain the barrel. Both in form and in being able have the proj…

Why couldn't there be small metallic wheels in the barrel making contact with the projectile? Wouldn't that prevent wear?

I imagine there's still a tremendous amount of unstable vibration being introduced by sudden acceleration to mach 7. There's just lots of force involved in these things.

Re: Navy tests rail gun

#99

Post by jug6ernaut »

mrfusion wrote: post #94
jug6ernaut wrote: post #82

Earlier quoted context omitted.

The amperage is not the issue(main issue at least). The way a rail gun works the projectile(or its casing) must make physical and solid contact with the barrel. This is because the electric current actually flows through the projectile from one rail to the other rail[1]. This produces huge amounts of wear on the barrel, making it extremely difficult to maintain the barrel. Both in form and in being able have the proj…

Why couldn't there be small metallic wheels in the barrel making contact with the projectile? Wouldn't that prevent wear?

I imagine you could do something like this.

Off the top of my head this would pose a few issues.

1) While the magnetic force must go from one rail to the other, the amount of electric force is effected by how much of the body is doing the conducting(if my memory servers me). So while you could use wheels, you would still want the current to flow through the entire(or large portion) of the projectile housing(for lack of a better term). This leads to the second issue.

2) Melting. With these huge amperage's there is also huge heat levels. If you were to conduct this much current through a small point(as would be the case with a wheel) the heat generated would be even worse. Most likely causing the wheels/barrings to melt.

Neither of which cant be accounted for, just issues that would have to be considered.

Re: Navy tests rail gun

#100

Post by csense »

macavity23 wrote: post #88
jug6ernaut wrote: post #66

Earlier quoted context omitted.

> While it's unlikely that this will allow the aircraft carrier to regain the place it once held... Care to elaborate on this? I was under the impression aircraft carriers were still our best general purpose military tool? (wartime/peacetime/force projection/ect)

They're great against a low-tech adversary, but against serious ballistic or (some) cruise missiles, they're just slowly-moving seaborne apartment blocks. Good writeup here: http://exiledonline.com/the-war-nerd-this-is-how-the-carrier...

This is really informative. You should submit it.
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