PRC/PLAN Laser and Rail Gun Development Thread

[iewgnem]

It's long and pointy and looks sci fi in camo.

Seriously though, I doubt this is a railgun. Or indeed any gun.

An EM accelerator for guided scramjet projectiles could be considered both a gun and not a gun

 

[bsdnf]

suppose the device is even 1 Megawatt (which is plausible). This is not its continuous power output. I imagine it operating at maximum for a few seconds(1-2) while engaging a high-flying target. Even if it operates for 1 hour, the total energy requirement would be 1 MWh. Using current battery technology, the battery would weigh a maximum of 5-6 tonnes. However, I believe it wouldn't even need this much energy. Even if it engages 300 subsonic cruise missiles in a saturation strike scenario, it would only need to operate at maximum power for about 10 minutes, consuming only one-sixth of the battery power.

I assume most of the bulk goes into cooling, as the power level in the fibers must be very high. On the other hand, a commercial Raycus fiber laser of 220 KW (a more common high-power industrial model), a continuous-wave laser with that much power coming from a fiber only a few hundred microns thick. Therefore, this military laser should be multiple times more powerful than commercially available ones. I think around 1 MW is feasible, and the aperture might have been increased to better deal with atmospheric attenuation and beam spreading.

Isn't it possible for China to combine 4-5 Raycus-type fiber lasers into one unit and add some adaptive optics and other components?

PLAN had mastered super powerful LFP batteries with a discharge rate of 75C, a single power of 5kw/kg, and an energy density of 80W⋅h/kg 8 years ago. I calculated using LLM that even if it were to operate continuously for 10 minutes without any charging and relying solely on energy storage, it would only require 2 tons of batteries.

 

[dingyibvs]

I think the limitation will be the optics or the light emitter. I don't think they can withstand continuous high power output.

 

[gelgoog]

Lasers are hugely inneficient at converting energy into light. If anyone ever fixes that, like we did when we switched from incandescent to LED lightbulbs, then lasers would be way more practical.

 

[siegecrossbow]

Bigger issue than raw power are cooling and light diffraction/distortion at sea. Another issue is compensating for motion of waves when firing.

 

[gelgoog]

If lasers were more efficient at converting energy into light you would have less waste heat. Less need for cooling. As for atmospheric distortions you can correct those with adaptive optics.