LAGARTO contacted USS BAYA (SS-318), already patrolling in Siam Gulf on 2 May 1945, and exchanged calls with her by SJ radar. Later that day BAYA sent LAGARTO a contact report on a convoy she had contacted consisting of one tanker, one auxiliary and two destroyers. LAGARTO soon reported being in contact with the convoy, and began coming in for an attack with BAYA. However, the enemy escorts were equipped with 10 cm radar, and detected BAYA and drove her off with gunfire, whereupon the two submarines decided to wait and plan a subsequent attack.
Early on the morning of 3 May 1945, LARGARTO and BAYA made a rendezvous at about 7!-55'N;102!-18'E and discussed plans. LAGARTO was to dive on the convoy's tack to make a contact at 1400, while BAYA was to be ten to fifteen miles further along the trank. During the day, numerous contact reports were exchanged. At 0010 on 4 May after a prolonged but unsuccessful attack, BAYA was finally driven off by the alert escorts, and no further contact of any kind was ever made with LAGARTO.
Japanese information available now records an attack on a U.S. submarine made by the minelayer HATSUTAKA, believed to be one of the two radar-equipped escorts of the convoy attacked. The attack was made at 7!-55'N;102!E in about 30 fathoms of water, and in view of the information presented above, the attack here described must be presumed to be the one which sank LARGARTO.
This vessel's first patrol was in the Nansei Shoto chain as part
of an antipicket boat sweep made by submarines to aid Admiral Halsey's
Task Force 38 in getting carrier planes to Japan undetected. She sank the
Japanese submarine I-371 on 24 February 1945, and participated in several
surface gun attacks with USS HADDOCK II (SS-231) and USS SENNET
(SS-408). Two small vessels were sunk and two more damaged in these attacks,
and LARGARTO shared credit for the results with these submarines.
Cdr. Latta had previously made seven patrols as Commanding Officer of
USS NARWHAL II (SS-167). Every patol made by this officer was designated
successful for the award of combat insignia, a record surpassed by no commanding
officer in the Submarine Force.