[gurps] [VEHICLE] of the week 731 ? Planetary Defense Battery

[Anthony Jackson]

Onno Meyer wrote:
> 
> Mines don't leave wakes, and most do not swim close to the surface,
> either.

Mines targeted at surface shipping most certainly float near the 
surface, at least compared to where a meson sub would go (a meson sub 
might be consistently below 500 meters).

> On the other hand, -1 per yard would mean a nominal range around 70
> million miles, certainly a no-go.

-1 per yard is for water with a substantial amount of mud or silt. Clear 
water would be -1 per 5-10 yards. There should be another -1 for surface 
effects.