National Environmental Policy Act: Development of the Crew Exploration Vehicle
“Alternatives considered but not evaluated further included extending Space Shuttle service and weighing different CEV concepts. Refurbishing the Space Shuttle for long-term cargo delivery and human access to the International Space Station was considered impractical. Major modifications to the Shuttle’s design to improve crew safety significantly (e.g., a crew escape system) cannot be implemented easily. Moreover, the Shuttle was not designed to withstand the Earth re-entry speeds of a Lunar mission. If flights were to be extended beyond the planned retirement in 2010, the fleet would require recertification, a costly and lengthy process. Moreover, the President has decided to curtail Shuttle operations after 2010.”
