Part II : 1950-1957
Baby Bear, Mama Bear, and Papa Bear
 Concurrent with the engine testing was an extensive program of component testing, and the combined operations created a heavy demand for liquid hydrogen, a situation anticipated by the Air Force.
Capt. Jay Brill's primary assignment on the Suntan management team was the logistics of liquid hydrogen. In one of his first moves, he contacted the Atomic Energy Commission to scrounge the excess equipment used for the "wet" hydrogen bomb program. He was able to obtain several of the refrigerated transport dewars developed for the AEC program (p. 68). In April 1956, he began a survey of industrial firms to assess their capability and interest in building hydrogen liquefiers and producing liquid hydrogen for the program. Wright Field had prepared a specification for liquid hydrogen which was given the code name "SF-l" fuel. Brill was accompanied on his visits by Marc and Blackwell (Blacky) Dunnam. Marc was chief of the fuels and oil division of the Power Plant Laboratory and Blacky had experience with cryogenic equipment. They visited the Linde Company in New York, Hydro-Carbon Research in New Jersey, and the Air Products Company in Allentown, Pennsylvania. Brill returned to Dayton convinced that large hydrogen liquefiers could be built with existing technology. The Arthur D. Little Company was awarded a contract to serve as a consultant in hydrogen liquefaction and to study hydrogen handling and safety  procedures. The Air Force also made use of the services of Russell Scott and other experts at the Bureau of Standards Cryogenic Laboratory at Boulder.32
In his survey of industrial firms, Brill found that there was plenty of gaseous hydrogen capacity by several processes. One firm produced excess hydrogen as a byproduct in Painesville, Ohio. This was near Pesco Products division of Borg Warner Corporation, a firm Appold had involved in developing a liquid hydrogen transfer pump for the CL-400 airplane. It was also near the NACA Lewis Laboratory, which would soon need liquid hydrogen for its flight investigation. For these reasons, the Air Force contracted with Air Products, about May 1956, to build a 680-kilogram-per-day liquid hydrogen plant in Painesville. At the same time, two other contracts for similar size plants were awarded. One was to Stearns-Roger for a plant at Bakersfield, California, to support the CL-400 program at Lockheed and the other was to HydroCarbon Research for a plant to support Pratt & Whitney at East Hartford. The Painesville plant was named "Baby Bear" and was the first to become operational, in May 1957, at a cost of $2 million. The California plant was placed into operation in the fall of 1957, but the contract with Hydro-Carbon Research was cancelled for budgetary reasons.33 Pratt & Whitney's initial hydrogen needs at East Hartford, over its own capacity, were supplied by truck from Baby Bear.
Another of Brill's tasks was the transportation of liquid hydrogen. Specifications for over-the-highway trailers had been drawn up by Wright Field and a contract was awarded to the Cambridge Corporation. Concurrently, permission was sought and obtained from the Interstate Commerce Commission to transport liquid hydrogen over the highway. The trailers were labeled "flammable liquid," since to reveal the true contents would blow the security cover. The U 1 semi-trailer built by the Cambridge Corporation had a capacity of 26 500 liters, with a hydrogen loss rate of approximately 2 percent per day. Figure 46 shows the U-1 and its successor, the U-2. The latter's specifications were issued on 15 March 1957 because the U-1 ran into a natural, but unanticipated, problem. The very low density of hydrogen made tandem axles on the semi-trailer unnecessary, so the U-1 had only one. During subsequent use of this equipment, there occurred an endless series of problems, all stemming from the single axle, which was unheard of for such a large trailer. It seems that each time one of these large semi-trailers went through a state weighing station, it roused suspicion, doubt about the equipment, and inquiries about the nature of the load.* The Suntan team considered painting a false second axle on the trailer but this was too obvious, and they gave in by ordering the U-2 with its second axle-one that was not needed for the load but which raised no questions on the road.34
To satisfy the anticipated demands for liquid hydrogen at Pratt & Whitney's Florida test center, the Air Force decided to locate a large hydrogen liquefaction plant nearby. United Aircraft obligingly deeded a tract of land to the government for the plant. The Air Force was unsuccessful in interesting private capital to put up the plant, so it funded its construction and operation by Air Products. The plant, with a 4500 kilogram-per-day capacity, was placed in operation in the fall of 1957, at a cost of $6.2...
....million.35 The Suntan team called this plant "Mama Bear," but locally it was known as the APIX fertilizer plant. APIX was an acronym for Air Products Incorporated, Experimental; the fertilizer association was encouraged by the Air Force and Air Products to conceal the true identity of the product.** Mama Bear used crude oil 'in a chemical process to obtain gaseous hydrogen. Liquid hydrogen storage tanks at the plant were connected to the Pratt & Whitney test cells by a double-wall, vacuumjacketed 7.5-centimeter line, 610 meters long. By April 1958, the line had carried 833 000 liters of liquid hydrogen at rates up to 1700 liters per minute for component and engine tests.
 Even before Mama Bear was completed, the Air Force planned a much larger hydrogen liquefaction plant to meet the anticipated testing needs of the 304 engine development. The contract was awarded to Air Products in 1957, and the plant was built a few hundred yards away from Mama Bear. It cost $27 million and when placed into operation in January 1959, had a capacity of 27 200 kilograms per day-the world's largest. Crude oil was first used to obtain gaseous hydrogen but later methane was used. This plant, called "Papa Bear," came too late for the Suntan program but served a very useful role in the space program that followed.
** Workmen were
observant and soon the word spread locally that hydrogen ws
involved. A retired Army colonel, in his role in Civil Defense,
became alarmed that a hydrogen bomb was being manufactured in the
midst of an unsuspecting community. A delegation of security
officials from Washington had to visit him and convince him to
keep quiet. Interview with Col. A. Gardner (USAF, ret.). 19 Sept.