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US Navy's Railgun Now Undergoing Tests in New Mexico

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Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#61
Sadly, news these days involves a lot of "we've invented , to kill people that disagree with us". Often the word "disagree" is replaced with "undermine" or "threaten". It's all the same human-life-ending bullshit. I don't feel at home in this world any more. When I was 18, I enlisted in the armed services and "did my part" as people often say. What a fucking mistake, I'm humiliated and embarrassed every single day to have played "my part" in any of this. The modern-day me wishes I could go back to the 18-year-old me and turn my weapon on my masters when they were all gathered to cheer us on. Unfortunately, I'm sure dozens would have stepped in to take their place as quickly as I ended them.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#62
post #51

Does anyone know why there is a flash of light and a puff of smoke when the gun fires? Since it's electromagnetic, you'd think you wouldn't see anything.

although there is no gunpowder, the acceleration in a railgun is quite violent and the projectile needs to contact both rails while it is being accelerated. the smoke is probably just from the friction of the projectile against internal components. the flash could be from the same or an electrical arc (railguns use very high voltages).

another possibility for the "smoke": powerful railguns often use a pressurized gas to start the process of firing. if the projectile were stationary at the time that current was applied, it might be spot welded in place.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#65
post #37

Earlier quoted context omitted.

Really hard engineering pushing the limits of physics and materials science is fun, killing people is not.

Do you genuinely see the same virtue in the engineering of a bridge and the engineering of a cruise missile?

Do you not see that materials science from high performance cruise missiles might work its way through other uses of materials science such as structural engineering and bridges? Bridges can be used to hold tanks, does that mean all bridge engineers are bad?

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#66
post #51

Does anyone know why there is a flash of light and a puff of smoke when the gun fires? Since it's electromagnetic, you'd think you wouldn't see anything.

A railgun, while its mechanism is electromagnetic, works on a base level by causing a massive high-current electrical short.

As a side effect (as in most electrical shorts), both the rails and some of the projectile are vaporized when the gun is fired due to both friction and electric arcing; and that's the smoke and fire you see.

This wear (which is signifcant per shot) is also the main obstacle to actually using railguns in any significant capacity in warfare (the other being the need for a massive current source, but nuclear generators and massive capacitor banks help).

Coilguns, on the other hand, don't actually touch the projectile they fire, and as such have a significantly cleaner output.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#67

Sadly, news these days involves a lot of "we've invented , to kill people that disagree with us". Often the word "disagree" is replaced with "undermine" or "threaten". It's all the same human-life-ending bullshit. I don't feel at home in this world any more. When I was 18, I enlisted in the armed services and "did my part" as people often say. What a fucking mistake, I'm humiliated and embarrassed every single day to…

??

Sadly, news these days involves a lot of "we've invented , to kill people that disagree with us".....The modern-day me wishes I could go back to the 18-year-old me and

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#68
post #65

Earlier quoted context omitted.

Do you genuinely see the same virtue in the engineering of a bridge and the engineering of a cruise missile?

Do you not see that materials science from high performance cruise missiles might work its way through other uses of materials science such as structural engineering and bridges? Bridges can be used to hold tanks, does that mean all bridge engineers are bad?

There's no way other than weapons engineering to make those discoveries?

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#69

Sadly, news these days involves a lot of "we've invented , to kill people that disagree with us". Often the word "disagree" is replaced with "undermine" or "threaten". It's all the same human-life-ending bullshit. I don't feel at home in this world any more. When I was 18, I enlisted in the armed services and "did my part" as people often say. What a fucking mistake, I'm humiliated and embarrassed every single day to…

[deleted]

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#70
post #51

Does anyone know why there is a flash of light and a puff of smoke when the gun fires? Since it's electromagnetic, you'd think you wouldn't see anything.

A combination of three things: 1) The flash is air in contact with the super-hot rail ionizing instantaneously from the heat, and becoming plasma. 2) Friction (From the projectile against both the rail itself, and air) producing vast amounts of heat, which then a) causes water vapor in the air to flash to steam b) produces smoke from burning metal

I am not sure how much of the smoke is from 2)b), because I'm assuming the surface materials are designed to minimize friction and therefore surface burning.

[1] https://www.quora.com/When-a-railgun-is-fired-where-does-the...

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