Not necessarily.
These weapons will also fire precision guided munitions which can use GPS, Infrared, etc. to hit both stationary and moving targets.
They are not powered in the sense that they have any kind of engine, but their control surfaces will allow them to manuever while airborn and hit the target.
Must be a closely guarded secret how the Navy plans to ‘harden’ the electronic guidance system against the tremendous EMF produced by the rail gun, huh? Sounds like somebody might be selling the Navy a bill of goods when it comes to smart war shots for these rail guns.
The other technical problem is how to make the “barrel” of the rail gun last more than a few dozen shots. Haven’t solved that little problem yet, either.
I’m sure the Navy is working on solving these problems in parallel. But the delays can be expensive.
“These weapons will also fire precision guided munitions which can use GPS, Infrared, etc. to hit both stationary and moving targets.”
The Chinese are very proud of their new aircraft carrier, which would seem to be a likely target for this weapon.
On the other hand, their spies have probably obtained the blueprints for the naval rail gun and will probably deploy land and ship-based rail guns before too long to augment their ballistic missiles to enforce their “inner island exclusion zone” strategy against large targets such as our carriers and amphibious landing ships.
It is very hard to jam a GPS receiver located above you that is obviously looking up. It could conceivably be intercepted with an ABM system, but that is going to require firing a few golden arrows at clay bricks. The enemy would quickly become depleted and saturated, while the ship's supply of ammunition would just keep flowing.
This could be a real game changing capability. Laser, IR, or radar guidance could make it a tremendous, long-range anti-aircraft weapon, although I'm not sure that those seeker types can survive the acceleration.