The Gun Fire Control System on the LST 325 in its current configuration consists of:
2 Mk 51 Gun directors
2 Twin 40 mm mounts
4 Single 40 mm mounts
Forward battery consists of mounts 41 (twin), 42, 43 and Director 41
Aft battery consists of mounts 44, 45, and 46 (twin)and Director 42
with 43 and 45 being on the starboard side and
42 and 44 being on the port side.
Gun director 41 is the forward director with Gun director 42 the aft director.
Gun director 41 controls the forward battery while Gun director 42 controls the aft battery.
The forward director can not control the aft battery and vice versa.
Rotary selector switches at each director and each 40 MM single mount enable a director to control either or both of the single mounts in its sector. The director is connected directly, without switching, to its sector 40 MM twin mount for control.
The rotary switch in the forward director selects 42, 43 BOTH OFF.
The rotary switch in the aft director selects 44, 45 BOTH OFF.
Examples: Gun Director 41 in OFF position controls the twin mount only.
In the 42 position it controls the twin mount and mount 42.
In the 43 position it controls the twin mount and mount 43.
In the BOTH position it controls the twin mount, mount 42 and mount 43.
Gun director 42 works in the same fashion.
Firing cut outs prevent the mounts from firing when the gun is pointed at any part of the ship.
The mounts themselves could select to be controled by mechanical hand cranks (in the event of power failure) or by electrical control using the control yoke at the pointer's station and AUTO utilizing the Gun directors.
Although each 40 MM mount has its own Mk 14 gyro gun sight to assist in aiming, there was an advantage in using a gun director away from the mounts. The Gun director tub is higher than the mounts, which presents a better all-around view as well as being up and away from most of the gun smoke. By being able to control more than one mount, a whole lot more fire power could be directed at a target more accurately.
AS an added note, the person manning the gun director had to do his best to make smooth movements with the gun director. Any sudden or abrupt movements or jerks could cause one of the loaders or other mount personnel to loose their balance and fall. This might later result in the director operator being invited to a blanket party on the fantail.