This is one of the most technical oral histories in the Naval Institute’s collection because of Admiral Mumma’s long service as an engineering duty specialist. After his graduation from the Naval Academy in 1926, he served in the light cruiser USS Richmond (CL-9) and armored cruiser USS Seattle (CA-11) before becoming a member of the first crew of the aircraft carrier USS Saratoga (CV-3) when she was commissioned in 1927. In the 1930s he served in the destroyers USS Waters (DD-115) and Clark (DD-361), sandwiched around postgraduate study in engineering in Annapolis and France. As a result of his training, he decided to leave the unrestricted line and become an engineering specialist. He served in 1939-43 at the David Taylor Model Basin in Carderock, Maryland, and subsequently in the Bureau of Ships, where he ran the propeller desk. In 1944-45 Mumma was part of the Alsos Mission and Naval Technical Mission to ascertain German progress during World War II in technical development. In BuShips after the war he was involved with the origins of the Navy’s nuclear power program; this oral history contains many candid comments about his relationship with Admiral Hyman Rickover. In the 1950s Mumma served at the San Francisco Naval Shipyard and later commanded the David Taylor Model Basin and the Mare Island Naval Shipyard. From 1955 to 1959 he was Chief of the Bureau of Ships and oversaw the development of many new vessels, particularly the adaptation of the teardrop-shaped hull to nuclear attack submarines and the design of the first ballistic missile submarines.