An Evaluation of Two Alternate Propulsion Concepts for Bantam-Argus: Deeply-Cooled Turbojet+Rocket and Pulsed Detonation Rocket+Ramjet
The Bantam-Argus reusable launch vehicle concept is a smaller version of the original Argus single-stage-to-orbit launch vehicle design. Like the original Argus, Bantam-Argus uses a Maglifter launch assist system to provide an initial horizontal launch velocity. Bantam-Argus is designed to deliver 300 lb. payloads to low earth orbit and, like the full sized Argus, the baseline Bantam-Argus concept utilizes two liquid oxygen/liquid hydrogen supercharged ejector ramjets as prime motive power. This paper presents the results of an investigation of two alternate propulsion systems for the BantamArgus launch vehicle. First, a thermally integrated combined-cycle system consisting of two deeplycooled turbojets and two liquid rocket engines was evaluated. Second, a combination propulsion system utilizing two pulsed detonation rocket engines and two standalone ramjets was evaluated. The results show that both alternate propulsion systems have the potential to reduce both the dry weight and gross weight of the baseline Bantam-Argus concept (when resizing the vehicle while holding mission payload constant). The pulsed detonation rocket engine option is particularly attractive. However, these results must be treated with caution given the relative immaturity of the supporting propulsion data available for both alternatives. Trade studies on key performance parameters were p rformed to bound the potential gains to be expected from either alternative.
Improvements and Enhancements to SCCREAM, A Conceptual RBCC Engine Analysis Tool
34th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit 
Cleveland, OH, July 12 - 15, 1998.
Integration of Cost Modeling and Business Simulation into Conceptual Launch Vehicle Design
NOMENCLATURE This paper reports on research that integrates cost modeling and business simulation into conceptual design environments for advanced launch vehicle programs. A new design-oriented computer tool has been developed and used that is capable of using priceelastic market estimates, price optimization, vehicle characteristics, and historical operations data to predict key business indicators such as return on investment (ROI), internal rate of return (IRR), maximum exposure, and break-even point (BEP). This paper includes a brief introduction to this tool called Cost And Business Analysis Module (CABAM). In addition, this paper reports on the results of work to integrate the cost analyst, via CABAM, into the advanced conceptual design process (i.e. performance, propulsion, aerodynamics, weights, internal layout, aeroheating, etc.). Using industry standard tools and design practices within a controlled university environment, three sample launch vehicle concepts were designed with varying levels of participation from the cost analyst. Successes and difficulties in integration of CABAM are documented. Then, the resulting economic indicators are presented and interpreted for each of the three example conceptual designs to illustrate the type and range of data available. These example results illustrate the potential cost savings and increased profit generation possible when a 'design-for-business' philosophy is used.