In these endeavors, Admiral Burke had strong support from the Secretary of the Navy Charles Thomas. Research challenges Work on the marine version of the Jupiter missile gained momentum in 1956, while the year 1959 was sets as the date of dispatch for the first modified missiles on board commercial vessels at sea. For the naval version of the missile a drive based on solid fuel was considered. Some studies had showed, that this could be used in nuclear-powered submarine with ballistic missiles up to 8,300 tonnes. During the program, the US Navy had doubts about the application of liquid fuel missiles on board, so initiated studies on the possibility of the use of drives on solid fuel, which, however, limited the ability to transfer cargo. A breakthrough in this area occurred in 1956, when scientists discovered a way to significantly reduce the size of thermonuclear warheads. Father of the American hydrogen bomb - Dr. Edward Teller had stated in the summer of 1956, that soon heads weighing 400 pounds (181 kg) will have the power of a bomb explosion 5000-pound (2270 kg). In September that year, the US Atomic Energy Agency estimated, that such a small nuclear warhead would be available in 1965, with some chance of making it back in 1963. The development of this specific program coincided with the intensive work on the high thrust drive on solid fuels. These developments made admiral Raborn decide, August 1956, to initiated a joined program with the US Navy and US Army. It was connected with the formal initiation of the small solid-fuel missile, which has been accepted by the Secretary of Defense in December 1956. Program Evaluation and Review Technique PERT Program Evaluation and Review Technique PERT is developed for the U.S. Navy Special Projects Office in 1957 to support the U.S. Navy's Polaris nuclear submarine project. PERT was developed primarily to simplify the planning and scheduling of large and complex projects, and has found applications all over industry. PERT had been made public in 1958 in two publications of the U.S. Department of the Navy, entitled Program Evaluation Research Task, Summary Report, Phase 1. and Program Evaluation Research Task, Summary Report, Phase 2. In a 1959 article in The American Statistician Willard Fazar, Head of the Program Evaluation Branch, Special Projects Office, U.S. Navy, gave a detailed description of the development, that led to the Program Evaluation and