The Bliss-Leavitt Mark 7 torpedo was a Bliss-Leavitt torpedo developed and produced by the E. W. Bliss Company and the Naval Torpedo Station in Newport, Rhode Island in 1911. The Mark 7 was a major step in the evolution of the modern torpedo. This innovative design featured the use of steam, generated from water sprayed into the combustion pot along with the fuel. The resulting mixture dramatically boosted the efficiency of the torpedo, leading to markedly improved performance. The Mark 7 torpedo was issued to the US Navy fleet in 1912 and remained in service through World War II. This torpedo was also experimented on as an aircraft-launched weapon in the early 1920s.