Japanese submarine Ro-116

The Ro-116 was a submarine of the Imperial Japanese Navy, part of the Ro-100 class, commissioned in January 1944. Designed with a displacement of 1,250 tons (surfaced) and 1,450 tons (submerged), she measured 67 meters in length and had a beam of 6 meters. Powered by diesel-electric engines, the Ro-116 could reach speeds of up to 19 knots when submerged and 14 knots on the surface, with a range of 8,000 nautical miles at 12 knots.

Constructed by Kawasaki Heavy Industries, she was laid down in January 1943, renamed Ro-116 in July 1943, and launched in September 1943 before being commissioned the following year. During her service, the Ro-116 was assigned to Scouting Line NA alongside other Japanese submarines. On May 24, 1944, she was intercepted by the USS England (DE-635), part of a hunter-killer group sent to neutralize the submarine line. Despite attempting evasive maneuvers and sonar jamming, Ro-116 was sunk by Hedgehog projectiles from the USS England at coordinates 00°53′N 149°14′E. All 56 crew members were lost, with debris recovered after sunrise.

Declared presumed lost on June 25, 1944, and struck from the Navy list on August 10, 1944, the Ro-116's loss marked one of several successes for the USS England in May 1944.