Heavy-lift launch vehicle options for future space exploration initiatives

A review of present heavy-lift launch vehicles (HLLV) capable of placing heavy payloads in earth orbit is presented and the basis for an emerging consensus that an HLLV will be required in the near future is discussed. Some of the factors for the policies governing the roles and requirements for these vehicles in the future, such as cost, technology development, and lead time to first use are addressed. Potential Space Station Freedom application is discussed as well as application to the proposed initiatives for human exploration of Mars and the moon.