Phase B Extended and a New Approach to the Shuttle
While Low and others at NASA headquarters in Washington were considering a glider or smaller shuttle, NASA’s engineers, particularly at the Manned Spacecraft Center (MSC) in Houston, and the shuttle study teams at NASA’s contractors were examining alternative ways of moving forward with an affordable program while still retaining the operational capabilities of the full-size shuttle in terms of payload capture and cross-range. They also were resisting the phased development approach advocated by NASA headquarters, which involved postponing development of a reusable booster. The engineering team at MSC had during the summer converged on an orbiter design that seemed to meet all requirements. This design, designated MSC-040, had triangular-shaped delta wings, a 15 x 60 foot payload bay, and a single expendable propellant tank containing both hydrogen fuel and oxygen oxidizer mounted under the airframe belly. That design would turn out to be the basis for the shuttle orbiter that eventually would be approved for development.
On September 14, the NASA human space flight leadership called its contractors together at MSC to discuss various changes in study direction. One shift of lasting significance was that all contractors were told to use the MSC-040 orbiter design as the baseline for further studies. NASA also directed the contractors to study a “phased technology” approach as a way of reducing short-term and peak funding requirements for shuttle development. In this approach, a “Mark I” orbiter using the MSC airframe design would be developed first; it would use existing technology, mainly derived from the Apollo program, as much as possible in areas such as thermal protection, on-board electronic systems, and rocket engines. After a few years, a “Mark II” orbiter would be developed, incorporating advanced technology in terms of the thermal protection needed for demanding cross-range missions, a new high-pressure space shuttle main engine, and state-of-the art electronics. Only the Mark II orbiter would be able to meet all NASA and national security requirements. This approach spread out over a longer time the total cost of orbiter development, thereby lowering the annual budget required but resulting in a higher overall program cost.
There was a major political problem with the Mark I/Mark II approach to shuttle development. NASA in July had announced that it had selected the Rocketdyne Corporation to develop the new rocket engine for use in the shuttle. But the Mark I orbiter would use modified Apollo-vintage J-2 engines, and thus the new engines would not be needed for several years; this put NASA in a potentially embarrassing position vis-a-vis Rocketdyne, a California-based company, at a time when the White House was eager to see all possible high technology government contracts go to that state. (Rocketdyne’s main competitor for the engine contract, Pratt & Whitney, with its rocket engine facility in Florida, lodged a formal protest regarding the contract award, implying that political considerations had played a role in Rocketdyne’s selection.) There was some merit to that argument. When Richard Nixon learned of the protest and the possibility that the engine contract might be taken away from a California company, his request was “if the contract does not go to the California firm, the White House should review the matter and possibly cancel the contract.”22