USS Tigrone (SS/SSR/AGSS-419), a Tench-class submarine, was the only ship of the United States Navy to be named for the tigrone, a tiger shark found in tropical waters. Her keel was laid down on 8 May 1944 by the Portsmouth Navy Yard. She was launched on 20 July 1944 sponsored by Mrs. Mary B. Grisham (née Breault), wife of Captain Charles F. Grisham, USN, Superintendent of the Portsmouth, N.H., Navy Yard, and commissioned on 25 October 1944.
Tigrone completed fitting out in mid-November and conducted training out of Portsmouth, New Hampshire, and New London, Connecticut, before departing the Submarine Base at New London on the last day of 1944. After ten days of training at the Fleet Sound School, the new submarine got underway on 16 January. Steaming via the Canal Zone, she paused for a week of training off Panama, then set her course for Hawaii, conducting extensive practice approach exercises with attack transport en route. On 16 February, she arrived at Pearl Harbor to prepare for her first war patrol.
First patrol
On 9 March, she departed Oahu and steamed westward, arriving at Guam on 19 March. After a three-day pause to repair a main engine, she got underway on 21 March in company with submarines and , members of a combined attack group, led by her own commanding officer, Commander Hiram Cassedy. Joined by , the submarines set their course for the South China Sea where they formed a scouting line in hopes of intercepting Japanese shipping.
Seahorse was mistakenly strafed and bombed by a B-24 Liberator on 24 March. Tigrone’s first brush with the enemy came on 29 March in the South China Sea when she dove to avoid an enemy "Oscar" and, at 60 ft (18 m), felt the jolt of a small explosion over the forward battery compartment, apparently the concussion of a small bomb dropped by the enemy plane. The new submarine emerged from this encounter without damage and continued her patrol of the sea lanes off the China coast.
In the days that followed, she made an unsuccessful attempt to intercept a convoy spotted by American planes. Then, on 3 April, she began lifeguard duties off the eastern shore of Hainan. On 5 April, Tigrone again managed to evade a bomb dropped by a high-flying Japanese plane. On 8 April, she assumed a lifeguard station off Kuannan and began steering five mile (8 km) legs to maintain her station, when the ship's commanding officer noted a wake which he took to be one of the ship's own. Two minutes later, the appearance of a torpedo away on the port bow gave startling proof that the wake was that of an enemy submarine. As Tigrone swung left, the torpedo passed her abeam, less than away. She then submerged and rigged for silent running, remaining below for over two hours.
On 9 April, she took up a lifeguard station off Mofu Point and continued patrols off Hainan until 15 April when she departed the area late in the day. She bombarded Pratas Reef near Pratas Island with five-inch (127 mm) gunfire on 16 April and joined submarine three days later to fire on targets including towns and docks on Batan Island. She ended her first war patrol at Guam on 24 April 1945.
Second patrol
After refitting by submarine tender , Tigrone departed Apra Harbor on 19 May, took on torpedoes at Saipan the same day, and on 20 May got underway for her assigned area. On 25 May, she sighted Sofu Gan Island and Tori Shima before taking up her lifeguard station south of Honshū and west of the Nanpō Islands. That same day, she rescued a downed flier from the 19th Fighter Command, Iwo Jima.
Early on the morning of 27 May, Tigrone engaged a Japanese lugger which countered the submarine's five-inch (127 mm) and 40 millimeter fire with machine-gun fire. As Tigrone turned away from the raking fire of the lugger, heavy seas washed over her main deck, knocking three of the submarine's crewmen against the gun and injuring them. Despite intermittent heavy rain, Tigrone finished off the lugger with five-inch (127 mm) fire. The final and telling round caught the lugger dead center, set it afire, and stopped it dead in the water. High seas made boarding a hazardous proposition, so the battered enemy vessel was left to burn, and Tigrone returned to her lifeguard station.