Our second goal is to develop and test a new spacecraft, the Crew Exploration Vehicle, by 2008, and to conduct the first manned mission no later than 2014. The Crew Exploration Vehicle will be capable of ferrying astronauts and scientists to the Space Station after the shuttle is retired. But the main purpose of this spacecraft will be to carry astronauts beyond our orbit to other worlds. This will be the first spacecraft of its kind since the Apollo Command Module.
The proposal to create the Orion spacecraft was partly a reaction to the Space Shuttle Columbia accident, the subsequent findings and report by the Columbia Accident Investigation Board (CAIB), and the White House’s review of the American space program. The Orion spacecraft effectively replaced the conceptual Orbital Space Plane (OSP), which itself was proposed after the failure of the Lockheed Martin X-33 program to produce a replacement for the space shuttle.
After the replacement of Sean O’Keefe, NASA’s procurement schedule and strategy completely changed, as described above. In July 2004, before he was named NASA administrator, Michael Griffin participated in a study called “Extending Human Presence Into the Solar System” for The Planetary Society, as a co-team leader. The study offers a strategy for carrying out Project Constellation in an affordable and achievable manner. Since Griffin was one of the leaders of the study, it can be assumed that he agrees with its conclusions, and the study may show insight into possible future developments of the CEV. Griffin’s actions as administrator supported the goals of the plan.
According to the executive summary, the study was built around “a staged approach to human exploration beyond low Earth orbit (LEO).” It recommends that Project Constellation be carried out in three distinct stages. These are:
- Stage 1 – “Features the development of a new crew exploration vehicle (CEV), the completion of the International Space Station (ISS), and an early retirement of the shuttle orbiter. Orbiter retirement would be made as soon as the ISS U.S. Core is completed (perhaps only 6 or 7 flights) and the smallest number of additional flights necessary to satisfy our international partners’ ISS requirements. Money saved by early orbiter retirement would be used to accelerate the CEV development schedule to minimize or eliminate any hiatus in U.S. capability to reach and return from LEO.”
- Stage 2 – “Requires the development of additional assets, including an uprated CEV capable of extended missions of many months in interplanetary space. Habitation, laboratory, consumables, and propulsion modules, to enable human flight to the vicinities of the Moon and Mars, the Lagrange points, and certain near-Earth asteroids.”
- Stage 3 – “Development of human-rated planetary landers is completed in Stage 3, allowing human missions to the surface of the Moon and Mars beginning around 2020.”
A number of changes to the original CEV acquisition strategy were explained in a NASA study called the Exploration Systems Architecture Study. The results were presented at a news conference held on September 19, 2005. The ESAS recommends strategies for flying the manned Orion by 2014, and endorses a Lunar Orbit Rendezvous approach to the Moon. The LEO versions of Orion was intended carry crews of four to six to the ISS. The lunar version of the Orion would carry a crew of four and the Mars Orion would carry six. Cargo would also be carried aboard an unmanned version of Orion, similar to the Russian Progress cargo ships. The contractor for the Orion is 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 Orion spacecraft (CEV) will be an Apollo-like capsule, not a lifting body or winged vehicle like the current Shuttle. Like the Apollo Command Module, Orion would be attached to a service module for life support and propulsion. It is intended to land in water but past versions had included plans for it to land on land. Landing on the west coast would allow the majority of the reentry path to be flown over the Pacific Ocean rather than populated areas. Orion will have an AVCOAT ablative heat shield that would be discarded after each use.
The Orion spacecraft (CEV) would weigh about 25 tons (23 tonnes) … almost four times the mass of the Apollo Command Module at 6.4 tons (5.8 tonnes) … and, with a diameter of 16.5 feet (5 metres) vice 12.8 feet (3.9 metres) provide 2.5 times greater volume.
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 is anticipated to be capable of carrying up to around 23 tons (21 tonnes) of cargo to the lunar surface to support a lunar outpost (t.b.d.). This weight in cargo is greater than the mass of the entire Apollo Lunar Module.
Like the Apollo Lunar Module, 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.
The Lewis and Clark expedition continues fallowed by another Neil Armstrong landing, Mars anyone?