Exploration Systems Architecture Study - CEV Configuration

CEV Configuration

The ESAS recommends strategies for flying the manned CEV by 2014, and endorses a Lunar Orbit Rendezvous approach to the Moon. The LEO versions of the CEV would carry crews four to six to the ISS. The lunar version of the CEV would carry a crew of four and the Mars CEV would carry six. Cargo could also be carried aboard an unmanned version CEV, similar to the Russian Progress cargo ships. The contractor for the CEV will be Lockheed Martin, which was selected by NASA in September, 2006 and is the current contractor for the Space Shuttle's External Tank and the Atlas V EELV.

The CEV re-entry module would weigh about 12 tons — almost twice the mass of the Apollo Command Module — and, like Apollo, would be attached to a service module for life support and propulsion. The CEV will be an Apollo-like capsule, with a Viking-type heat shield, not a lifting body or winged vehicle like the current Shuttle. It would land on land rather than water, similar to the Russian Soyuz spacecraft, though it would be capable of a water recovery if an emergency splashdown were needed. Possible landing areas that have been identified include Edwards Air Force Base, California, Carson Flats (Carson Sink), Nevada, and the area around Moses Lake, Washington state. Landing on the west coast would allow the majority of the reentry path to be flown over the Pacific Ocean rather than populated areas. The CEV would have an ablative (Apollo-like) heat shield that would be discarded after each use, and the CEV itself could be reused about 10 times.

Accelerated lunar mission development is slated to start by 2010, once the Shuttle is retired. The Lunar Surface Access Module (LSAM) and heavy-lift boosters would be developed in parallel and would both be ready for flight by 2018. The eventual goal is to achieve a lunar landing by 2020. The LSAM would be much larger than the Apollo Lunar Module and would be capable of carrying up to 23 tons of cargo to the lunar surface to support a lunar outpost. This weight in cargo is greater than the mass of the entire Apollo Lunar Module (LM).

Like the Apollo LM, the LSAM would include a descent stage for landing and an ascent stage for returning to orbit. The crew of four would ride in the ascent stage. The ascent stage would be powered by a methane/oxygen fuel for return to lunar orbit (later changed to liquid hydrogen and liquid oxygen, due to the infancy of oxygen/methane rocket propulsion). This would allow a derivative of the same lander to be used on later Mars missions, where methane propellant can be manufactured from the Martian soil in a process known as In-Situ Resource Utilization (ISRU). The LSAM would support the crew of four on the lunar surface for about a week and use advanced roving vehicles to explore the lunar surface. The huge amount of cargo carried by the LSAM would be extremely beneficial for supporting a lunar base and for bringing large amounts of scientific equipment to the lunar surface.