This first appeared in The Tinosa Blatt, April, 1988, page 12.
Excerpted from the book Encounter by Watrous and published by Wittmer in 1988.
Edited for web site.

On her arrival in Pearl Harbor on January 30, 1945, the Submarine Base and Subdiv 45 commenced a routine refit on TINOSA. The radar mast extension that had been installed in Hunter's Point was removed and, most notably, a ship alteration that was designed to allow the bow planes to be rigged out with a fifteen degree down angle, thereby decreasing the time to dive, was implemented. Eighteen men were transferred and replaced by a like number. The weapon load was identical to that of the previous run. On March 1 at 1426, TINOSA took departure Pearl Harbor en-route Saipan.

The trip to Saipan was uneventful except that she was forced to dive three times because of aircraft contacts. They were probably friendly aircraft, but even so, they might not act friendly toward a submarine. At 1046 on March 11, she moored alongside the tender FULTON in Tanapag Harbor, Mariana Islands. There she spent four days conducting special tests, and at 1334 on March 17, she departed for her patrol area in company with SPADEFISH.

Captain Latham was to command a wolf pack that consisted of TINOSA, SPADEFISH and TIRANTE. TIRANTE would join the pack later.

At 0605 on March 23, TINOSA dove to make a submerged transit of the Ryukyu Islands. The bow planes failed to rig out fully and would not tilt. A heavy sea was running and without bow planes it was impossible to maintain depth control at periscope depth, so Latham took the boat to 150 feet. A shear pin in the rigging gear had failed and this was replaced, but the planes would not rig out. The planes were rigged in with the intention of making repairs when the ship surfaced. Depth control was extremely difficult under these circumstances, and TINOSA frequently broached to thirty feet and was compelled to use negative tank to regain depth. The water here was not very deep and she hit bottom a couple of times.

At 1931 TINOSA surfaced. The bow planes were not fully rigged in, although the indicator showed them to be. The limit switches were reset to agree with the indicator in the hope that this would make the planes operable.

(While all this was going on, SPADEFISH sank a freighter fifty miles NNW of TINOSA).

At 0604 TINOSA conducted a trim dive from which she surfaced at 0631. The bow planes seemed to be working. At 0702 there was a visual aircraft contact, and she submerged and the noise in the bow planes made it obvious that there was a major defect in the gear train. The planes would tilt, but upon surfacing they would not rig in. The heavy seas were giving the rigged out planes a fierce pounding, so at 1147 Latham submerged. The bow plane tilting gear box was then disassembled and it was found that an indicator shaft had sheared. The main problem was not with the tilting mechanism but with the rigging gear. It appeared that some teeth on the gears had broken off. From now on the bow planes would have to be rigged in and out by hand after diving and before surfacing. TINOSA surfaced at 1904.

TINOSA was now in the East China Sea, west of the Ryukyu Islands, and on March 25th at 0641, she commenced a special mission - plotting mine fields. The invasion of Okinawa was less than a week off and this area was heavily mined. TINOSA was to supply important information on the location of these mines to the invasion fleet.

The day was spent in this exercise. While on the surface at 1620, a floating mine was sighted and an attempt was made to destroy it with gunfire but was not successful. At 2220 TINOSA tried to anchor so as to maintain her position but the anchor chain parted and she lost her anchor.

The next morning, another floating mine was sighted and it was destroyed with gunfire, and the following day another one was sunk in the same manner.

At 0628 on March 28, TINOSA sailed into a large oil slick in which were floating many bodies of Japanese soldiers and other debris. At 1232 a mast was sighted and Latham took his crew to battle stations. As TINOSA came closer, it was discovered that the target was a lifeboat under sail. There were seventeen Japanese in the boat and Latham drew alongside to take prisoners. At first they were reluctant to come aboard but Lieutenant Siegfried accidentally fired two rounds from his forty-five and then they all wanted to cooperate. The two with the most impressive uniform insignia were taken and the rest sent on their way. They were army aviators whose ship had been sunk by a U.S. Navy torpedo plane.

TINOSA then resumed the special mission in which she had been engaged. The mission was finished at 1843 that day and TINOSA then set a course for her assigned patrol area which was the same one in which patrol run seven had been conducted - the west coast of Kyushu and the south coast of Korea. At 0400 March 29, she was on station. At 1156 a uniformed body with an attached parachute was sighted, but there was no time to identify it because there was an aircraft in the area.

TINOSA made contact with SPADEFISH at 0109 on March 30, and the two boats exchanged information. At 0600 she submerged to conduct a patrol of the approaches to Nagasaki. Later that morning two distant depth charge explosions were heard but the day was otherwise without incident. At 1927 she surfaced only to discover that the bow planes were not fully rigged in and they promptly dropped to a rigged out position. It was necessary to dive again to rig them in

The next day Latham attempted to stay on the surface, but was forced to submerge three times to avoid enemy aircraft. At 1710 a small craft was sighted containing about forty Japanese in civilian clothes. The boat was similar to a landing craft and was apparently being used as a lifeboat from a sunken ship. Two prisoners were enough to handle and Latham allowed this boat load to go on its way.

On April 1 at 1134, TINOSA dove to avoid an enemy aircraft. While she was down, the sound operator heard pinging to the east. Latham changed course to close the range. By 1230 the top hamper of six ships could be seen. They did not appear to be large enough for a torpedo attack, and it was thought that they were minesweepers or fishing trawlers. Since the invasion of Okinawa had started, it was thought that this group of six might be making an anti-submarine sweep or clearing mines for larger combat ships that would be following to reinforce the Japanese fleet that was opposing the invasion. TINOSA surfaced to send a contact report, but was promptly chased under by two enemy aircraft. As soon as it was clear she surfaced, sent the contact report and commenced trailing the contacts to see what would develop.

At 1928 there came an aircraft contact report describing this group as landing craft escorted by two destroyers and a light cruiser. In an attempt to regain contact and in the hope of getting in an attack, Latham went ahead on four main engines, but was unable to find the targets.

April 2 was spent submerged and at 1931 she surfaced, and in accordance with a dispatch received earlier, set a course for Guam. At 1100 she received orders to take station for lifeguard duty where she remained until 0211 April 4. TINOSA then headed for Guam, and at 1400 on April 7, she moored alongside PROTEUS in Apra Harbor.

This was TINOSA's shortest patrol run to date. It was terminated because of mechanical difficulties, particularly with the bow planes. Unfortunately, there was no opportunity for torpedo attack or wolf pack operations because she was unable to roam due to her commitment to a special mission. Comsubpac designated the run successful, however, because of the data gathered on that special mission.

SPADEFISH and TIRANTE remained on station where the former sank two ships (4127 tons) and the latter six ships (13,071 tons). It was on this run that TIRANTE made her famous sortie into the harbor on Cheju for which her skipper was awarded the Congressional Medal of Honor.


Duration of patrol: 27 days

Ship Contacts: 15

Air Contacts: 21