Finally onto the BALAO class:
This is BALAO (SS-285) in October of 1944 after the completion of a refit period at Mare Island. She is camouflaged in Measure 32/3SS-B.
The BALAO class submarines were externally almost identical to the GATO class, with the main difference in their construction being the use of thicker high tensile steel to allow for a max diving depth of 600' versus the 400' limitation of the GATO class. The BALAO class were built with the cut-down bridge fairwaters retroactively fitted to the GATO class. The BALAOs benefitted from wartime experience with the GATOs, and all of them received a simplified periscope shears design that eliminated the heavy bracketing and complicated support structure from the previous design. BALAOs built by government yards (such as Mare Island and Portsmouth) were launched with oval limber holes along the entire length of the main deck, while Electric Boat yards (Groton and Manitowoc) continued to build their boats with only a single row of semi-circular limber holes forward. Government boats also featured a portside anchor, while the Electric Boat design mounted the single anchor to starboard.
BALAO herself mounts two 20mm Oerlikons on the fairwater positions, with a 4"/50-caliber Mark 12 deck gun forward. This would be replaced in 1945 with the usual 5"/25 Mark 40 mount seen on almost every sub towards the end of the war. BALAO has been fitted with the ST range-only radar set, visible as the small bump under the forward periscope's optic. This was a set similar to the ranging radars used aboard the surface ships, and performed the same function, allowing the officer using the periscope to quickly range his target. BALAO mounts the SD air search set on the new mast aft of the periscope shears, as well as the SJ-1 surface search set between them.
BALAO would survive the war to be sunk as a target in 1963.