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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.
It's a lot cheaper than the alternatives.
I can't imagine the amount of electricity (even just for a split second) it would take to pull this off.
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.
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…
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.
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.
I can't imagine the amount of electricity (even just for a split second) it would take to pull this off.
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...
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…
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…
I assume as testing progresses, it will end up on other types of ship.
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.
>> $25,000 for a railgun projectile versus $500,000 to $1.5 million for a missile It's a lot cheaper than the alternatives.
I can't imagine the amount of electricity (even just for a split second) it would take to pull this off.