The following subsections present the results of this assessment with the baseline cost modeling approach described and an assessment of the individual models, where possible. The chapter concludes with a discussion of the overall RBS business case.
The Air Force cost modeling approach uses a mixture of models and methodologies for estimating the various RBS elements. The configurations shown in Figure 4.1 represent the baseline flight vehicle designs examined by the committee. These include the reusable booster demonstrator (RBD) to be used to demonstrate and validate various aspects of the reusable booster design and operation as well as the RBS, which includes a heavy-lift variant to support larger payloads. The costs associated with the Air Force Research Laboratory’s (AFRL’s) funding of technology development efforts, including the Pathfinder small-scale demonstrator, are not included in the baseline costing, but they are relatively small.
The committee considered a number of scenarios for RBS system development. Four of them formed the basis for the analysis:
• Scenario 1: Baseline. The EELV program is assumed to end in 2031, and RBS development occurs in a time frame that would support the entire launch manifest. RBS development includes the mid-scale RBS demonstrator and
FIGURE 4.1 RBS flight hardware elements. Major elements include the RBD, the LES, the SES, and RBS. NOTE: LES, large expendable stage; RBD, reusable booster demonstrator; RBS, reusable booster system; SES, small expendable stage. SOURCE: Air Force Space and Missile Systems Center, SMC Developmental Planning, “Reusable Booster System Costing,” presentation to the committee, February 15, 2012. Approved for Public Release.