US Patrol Torpedo Boats Motor torpedo boat development began in the early 1900s and the vessels were first put into active service during World War I. However, it was not until the late 1930s that the US Navy commenced the development of their Patrol Torpedo or PT boat program. The PT boat, or the "mosquito boat" as they were sometimes known, was originally envisioned for attacking larger warships with torpedoes using it... Full description