Part II : 1950-1957
 The 1950-1957 period was one of great technological advances in the use of liquid hydrogen as a fuel in rockets and aircraft. Thermonuclear research provided the first large stimulus to hydrogen technology at the start of the period; from it came a large new cryogenics laboratory, larger hydrogen liquefiers, mobile dewars for transporting hydrogen, and other advances.
The Lewis laboratory of the National Advisory Committee for Aeronautics advocated liquid hydrogen for rockets in 1950 and for aircraft in 1954, conducted research showing hydrogen's potential, and demonstrated that liquid hydrogen could be safely used in manned flight.
The Air Force, always seeking to extend flight capabilities, took a strong interest in very-high-altitude flight in 1953, became interested in hydrogen for this purpose in 1954 as the result of an imaginative proposal of Randolph Rae, helped the Central Intelligence Agency develop the U-2 airplane using conventional fuel, and mounted a massive, crash project to exceed the U-2's performance by using hydrogen. The hydrogen airplane did not materialize, but the liquid hydrogen plants and test facilities constructed by the Air Force would find full utilization in the emerging space program.