By late 1962 NASA had made most of the basic decisions affecting the development of launch facilities and was ready to build the moonport. Contractors would start construction on the main buildings at launch complex 39 and in the industrial area, eight kilometers to the south, as soon as sufficient design information was available, and install equipment as construction proceeded far enough to allow safe access. At the same time, engineers were expanding and modifying the existing facilities at launch complexes 34 and 37 for earth-orbital tests of Apollo spacecraft launched by Saturn IBs.
Designers, meanwhile, were working on the final stages of the Apollo spacecraft. This complicated the design and equipment of facilities at the Launch Operations Center. The basic dimensions, weights, and operating principles of the rocket and spacecraft were known, but questions remained about specific sizes, types, quantities, flow rates, pressures, or even methods of use. Answers to many such questions awaited completion of designs at Huntsville and Houston. Policy makers had to make commitments on the basis of the best information available, knowing that costly and time-consuming changes might well become necessary.
Any large construction project passes through several common stages: selecting and preparing the site, choosing or developing the equipment for use in the operation, planning the external structure, and constructing and equipping the facilities. The pressure of time was such that, during the erection of the Apollo launch facilities, what would ordinarily be consecutive steps were often simultaneous.1
By working backwards from the earliest launch date (March 1966) and estimating the time required for vehicle assembly and checkout, the date when the basic launch facilities had to be in operation could be found. Working backwards further and estimating the time required for construction and outfitting yielded the date for the start of construction. Such computations showed, in 1962, that little time remained for development of criteria and detailed design.
The requirements of the manned lunar landing program found the Launch Operations Center facing some new problems, while some old problems were becoming more acute. The new were the size and complexity of the Saturn V vehicle; the need for unprecedented reliability, flexible launch rates, and a short recovery time between launches from the same pad; and the use of the mobile concept. These, in turn, raised old questions about the marshy composition of Merritt Island and the possibility of hurricanes.
Central to LC-39 would be an assembly building, where the Saturn V vehicle would be put together. The Saturn's size was such that the vehicle could not be transported as a unit from its place of construction, but had to be assembled and checked in a vertical attitude near the launch site. The major components were three stages, an instrument unit, and the Apollo spacecraft.
The design of the assembly building had to allow for stacking the 110-meter Apollo-Saturn space vehicle on top of its 14-meter-high movable launch platform. The structure would be taller than any building in Florida. To handle the stages of the vehicle, bridge cranes had to span 45 meters and lift 121 metric tons to a height of 60 meters. The architect-engineers faced complex problems, particularly since the structure had to be capable of withstanding hurricane winds.
To make room for the assembly and checkout of the various stages of three or four vehicles of this size simultaneously required an enormous building. The planners decided to have four high bays or checkout areas, each big enough to handle all stages of the Saturn V and the spacecraft in a stacked position - that is, completely assembled in an upright position ready for launch. The planners could foresee no situation that would require working on more than four rockets at one time; but if requirements changed, they could add more high bays at a later date. Additional low bays would accommodate preliminary work on single stages.