In early June, George Low noted that “during discussions with Dale Myers, we had repeatedly decided to look for a phased program approach, but had been unable to establish the technical feasibility of such an approach.” However, “during the past two or three weeks, because of the smaller orbiter made possible by moving the hydrogen tanks outside of the orbiter airframe,” a phased approach was “beginning to look like a technical possibility. Dale Myers and his centers are moving out to establish technical details for this approach.” He added, “in the meantime, von Braun’s group is putting together NASA long range plans, incorporating the phased shuttle development, so that the peak funding during the 1970s need not exceed $4 billion.” Fletcher and Low met with von Braun and his planning staff on May 26. At that meeting, von Braun had reported that “a reasonable shuttle alternative from both developmental and cost savings standpoints” appeared to be the orbiter with an expendable propellant tank, initially launched on an expendable booster, with “subsequent development of a fully reusable booster for use with that orbiter.”44
This advice reinforced the sense that Fletcher had gathered from his White House meetings and exposure to NASA’s thinking on the shuttle in his first month at NASA—that simultaneous development of both elements of a fully reusable two stage shuttle was not a viable approach in either budgetary or technical terms. He had told industry representatives on May 20 that he was not committed to the two-stage reusable approach. George Low had been thinking along the same lines since at least the preceding November. Fletcher, Low, and Myers decided in mid-June to investigate a phased approach; in doing so, they were in essence making a major decision—to give up hopes of developing simultaneously both elements of a shuttle system. Commenting on the influences that led to this decision, Fletcher suggested that three-fourths of the pressure for change came from financial constraints such as the $3.2 billion annual budget proposed in Don Rice’s May 17 letter to Fletcher, and one-fourth from “our own technical concerns” regarding the fully reusable design. With respect to the latter concern, Charles Donlan, who had been designated shuttle program director at
NASA headquarters, later commented that “It was not until the phase B’s came along and we had a hard look at the reality of what we mean by fully reusable that we shook our heads saying ‘No way you’re going to build this thing in this century.’ . . . Thank God for all the pressures that were brought to bear not to go that route.” Shuttle program manager Robert Thompson at the Manned Spacecraft Center in Houston agreed, saying that the fully reusable shuttle was “a bridge too far.”45
On June 16, NASA announced that it would be “examining the advantages of a ‘phased approach’ to the development of a reusable space shuttle system in which the orbiter vehicle would be developed first and initially tested with an interim expendable booster.” In addition, the NASA press release said, quoting Fletcher, “we have been studying. . . the idea of sequencing the development, test, and verification of critical new technology features of the system” such as its rocket engines, thermal protection, and electronic systems. Fletcher added “we now believe that a ‘phased approach’ is feasible and may offer significant advantages.”46 To give its contractors additional time to explore the implications of such an approach, NASA extended its study contracts, which were due to expire on June 30, by four months. Recognizing that with the adoption of the phased approach Mathematica’s analysis of the economics of a fully reusable shuttle had been overtaken by events, NASA also gave Mathematica a contract extension to examine the economics of alternative shuttle systems.
Even as he announced this shift in plans, Fletcher was pessimistic about the future of the shuttle program. Writing to leading space scientist James van Allen, who was scheduled to testify before Congress in opposition to the shuttle, Fletcher suggested that “the political cards are so heavily stacked against this program. . . that no opposition from the scientific community is necessary. I think you are shooting at a dead horse. . . My feeling is that those who oppose the shuttle program—and there are good reasons for opposing certain portions of it—would be wise not to say anything now and let nature take its course.”47
NASA’s shift in direction did not please all potential users of the shuttle. In particular, in response to the June 16 announcement, Secretary of the Air Force Robert Seamans suggested that “because of the extensive effort that has gone into the evolution of the current shuttle baseline, I believe it is a system that can perform our needs.” He suggested that phased development “would reduce the potential utility of the shuttle for DOD for an indefinite period.” Seamans urged NASA to make every effort to stay with “a reusable booster and orbiter with the 15 x 60 foot payload bay.” The continuing national security pressure on NASA to develop a shuttle meeting that community’s needs was a factor that could not be ignored.48
Also responding to NASA’s June 16 announcement that it was examining a phased approach to shuttle development, OMB’s Don Rice on July 20 noted that “in light of continuing fiscal constraints,” such a move was “very appropriate.” But Rice wanted more than just deferring booster development. He urged NASA as it rethought its strategy for the shuttle to place emphasis “on defining approaches which will substantially reduce the overall investment cost of the future space transportation system.” Rice wanted NASA to examine “alternative, lower cost systems” such as “expendable systems, partially expendable systems, the stage and one half concept.” Rice noted that “while the economic analyses conducted to date have been very useful, they have not covered the full range of alternatives,” a point that Mathematica was also making in its report. Rice wanted additional economic analysis with respect to alternative systems in terms of “estimated payload savings, realistic mission models, and alternative payload characteristics.” He would later reflect on “the difficulty of getting any attention paid to alternative [shuttle] designs,” noting “how hard it was to get an examination of alternative specifications of what you wanted to accomplish and the systems design that reasonably derived from that.”49
With its de facto decision to abandon concurrent development of a shuttle orbiter and booster, NASA had once again adjusted its plans to the reality of what kind of post-Apollo space program the Nixon administration might be willing to approve. Already the ambitious plan set out in the Space Task Group had been stillborn, and NASA had abandoned hope of developing simultaneously a large space station and the space shuttle. With the adoption of an expendable propellant tank design and particularly a phased approach to shuttle development, NASA was making a third major adjustment, giving up for at least some years, if not forever, on its plans to develop a fully reusable two-stage shuttle. The June 16 announcement opened the door to an intense and broad-ranging effort in the next several months to identify a shuttle system design that represented the best compromise among several conflicting objectives. They included:
• keeping the annual shuttle development budget at or less than $1 billion per year, the budget level that would fit within an overall NASA allocation of $3.2 billion per year that Don Rice had suggested was an appropriate target;
• minimizing the cost of shuttle operations so that the cost per flight was as low as possible;
• maximizing the number of future missions that the shuttle would fly, in order to spread the cost of shuttle development and operation across a robust mission model and thus make the investment in shuttle development economically sound; and
• retaining the capabilities that would convince the national security community to commit to using the shuttle and would allow NASA to plan for a future shuttle-launched space station.
Between June and December 1971, there was “a frantic search for the most cost-effective and technically sensible” shuttle design; in that search there were dozens of alternate configurations and development approaches considered. In the words of one close observer, during those months “everyone became a shuttle designer.”50