James Franklin "Frank" Caldwell Jr. is a retired admiral in the United States Navy who last served as director of the Naval Nuclear Propulsion Program, a job once held by the program's creator, Admiral Hyman G. Rickover. He previously served as Naval Inspector General.

Naval Reactors (NR), which administers the Naval Nuclear Propulsion Program, is an umbrella term for the U.S. government office that has comprehensive responsibility for the safe and reliable operation of the United States Navy's nuclear reactors "from womb to tomb." A single entity, it has authority and reporting responsibilities within both the Naval Sea Systems Command and the National Nuclear Security Administration (NA-30). Moreover, the Director of Naval Reactors also serves as a special assistant to the Chief of Naval Operations for Naval Nuclear Propulsion.