Liquid Rocket Booster (LRB) for the Space Transportation System (STS) Systems Study; Volume 1 - Executive Summary.

In October 1987, NASAMSFC awarded Martin Marietta Manned Space Systems a contract to study the feasibility of replacing the Space Transportation System STS solid rocket boosters SRBs with liquid rocket boosters LRBs, Figure 1.0-1. The main objectives of a LRB substitution for the SRB were increased STS safety and reliability and increased payload performance to 70.5K lb to low earth orbit LEO with minimum impacts to the STS. The basic scope of work was directed to the definition of optimum liquid rocket booster concepts for replacing SRBs within the current STS operational constraints and envelopes. The initial contract was phased in two parts. Part 1 was designated for establishment of a baseline configuration and system trade studies. Part 2 further defined the baseline, incorporating the results of the trade studies and preliminary analyses which were performed on the various systems. Life cycle costs LCC were developed for the program and new technology requirements were identified. In July, 1988 a six month extension, Part 3, of the study was awarded so that concepts could be further optimized, alternate applications for LRB could be explored, and planning and technical support for a pressure-fed propulsion system test bed could be provided. Figure 1.0-2 illustrates the LRB definition study flow. Two booster engine designs were studied. The first engine design was a turbo pump-fed engine with state-of-the-art design, and the second was a pressure-fed engine which might provide a lower cost alternative to the pump-fed concept. Both booster concepts were carried through to completion of conceptual design and all system impacts and program costs were identified.