Design options for advanced manned launch systems (AMLS)

Abstract

Various concepts for advanced manned launch systems (AMLS) are examined for delivery missions to Space Station and polar orbit. Included are single- and two-stage winged systems with rocket and/or airbreathing propulsion systems. For near-term technologies, two-stage, reusable rocket systems are favored over single-stage rocket or two-stage airbreathing/rocket systems. Advanced technologies enable viable single-stage-to-orbit (SSTO) concepts. Although two-stage rocket systems continue to be lighter in dry weight than SSTOs, advantages in simpler operations may make SSTOs more cost effective over the life cycle. Generally, rocket systems maintain a dry weight advantage over airbreathing systems at the advanced technology levels, but to a lesser degree than when near-term technologies are used. More detailed understanding of vehicle systems and associated ground and flight operations requirements and procedures is essential in determining quantitative discrimination between these latter concepts.