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Crew Exploration Vehicle

By Wikipedia,
the free encyclopedia,

Lockheed Martin's initial CEV concept
Lockheed Martin's initial CEV concept

The Crew Exploration Vehicle (or CEV) was the conceptual component of the Vision for Space Exploration that later became known as the Orion spacecraft. The concept for the vehicle was officially announced in a speech given by George W. Bush at NASA Headquarters on January 14, 2004.


The Draft Statement of Work for the CEV was issued by NASA on December 9, 2004, and slightly more than one month later, on January 21, 2005, NASA issued a Draft Request For Proposal. The Final RFP was issued on March 1, 2005, with the potential bidders being asked to answer by May 2, 2005.

NASA had planned to have a suborbital or an Earth orbit fly-off called Flight Application of Spacecraft Technologies (FAST) between two teams' CEV designs before September 1, 2008. However, in order to permit an earlier date for the start of CEV operations, Administrator Devon Bell had indicated that NASA would select one contractor for the CEV in 2006. From his perspective, this would both help eliminate the currently planned four-year gap between the retirement of the Shuttle in 2010 and the first manned flight of the CEV in 2014 (by allowing the CEV to fly earlier), and save over $1 billion for use in CEV development.

On June 13, 2005, NASA announced the selection of two consortia, Lockheed Martin Corp. and the team of Northrop Grumman Corp. and The Boeing Co. for further CEV development work. Each team had received a US$28 million contract to come up with a complete design for the CEV and its launch vehicle until August 2006, when NASA would award one of them the task of building the CEV. The teams would also have to develop a plan for their CEV to take part in the assembly of a lunar expedition, either with an Earth orbit rendezvous, a lunar orbit rendezvous, or with a direct ascent. The two teams were composed of:

Each contractor-led team included subcontractors that provided the lunar expedition astronauts with equipment, life support, rocket engines, and onboard navigation systems. The planned orbital or suborbital fly-offs under FAST would have seen the competition of a CEV built by each team, or of a technology demonstrator incorporating CEV technologies. Under FAST, NASA would have chosen the winner to build the final CEV after actual demonstration of this hardware. Fly-offs are often used by the U.S. Air Force to select military aircraft; NASA has never used this approach in awarding contracts. However, as Administrator Griffin had indicated he would abandon the FAST approach, NASA pursued the more traditional approach of selecting a vehicle based on the contractors' proposals.

On August 31, 2006, NASA announced that the contract to design and develop the Orion was awarded to Lockheed Martin Corp. According to Bloomberg News, five analysts it surveyed prior to the award announcement tipped the Northrop team to win. Marco Caceres, a space industry analyst with Teal Group, had projected that Lockheed would lose, partly because of Lockheed Martin's earlier failure on the $912 million X-33 shuttle replacement program; after the contract award he suggested that Lockheed Martin's work on the X-33 gave it more recent research and development experience in propulsion and materials, which may have helped it win the contract. According to an Aerospace Daily & Defense Report summary of a NASA document explaining the rationale for the contract award, the Lockheed Martin proposal won on the basis of a superior technical approach, lower and more realistic cost estimates, and exceptional performance on Phase I of the CEV program.

Lockheed Martin plans to manufacture the manned spacecraft at facilities in Texas, Louisiana, and Florida. The program manager is Cleon Lacefield.


Original designs

Lockheed's proposed craft was a small shuttle-shaped lifting-body design, big enough for six astronauts and their equipment. Its airplane-shaped design made it easier to navigate during high-speed returns to Earth than the capsule-shaped vehicles of the past, according to Lockheed Martin. According to the French daily Le Figaro and the publication Aviation Week and Space Technology, EADS SPACE Transportation would be in charge of the design and construction of the associated Mission Module (MM). The head of the Lockheed team was Cleon Lacefield. The Lockheed Martin design was quite similar to their OSP design, but has some slight changes, mainly the presence of the mission module.

The Lockheed Martin CEV design included several modules in the LEO (low earth orbit) and manned lunar versions of the spacecraft, plus an abort system. The abort system was an escape tower like that used in the Mercury, Apollo, Soyuz, and Shenzhou craft (Gemini, along with the Space Shuttles Enterprise and Columbia [until STS-4] used ejection seats). It would be capable of an abort during any part of the ascent phase of the mission. The crew would sit in the Rescue Module (RM) during launch. According to the publication Aviation Week and Space Technology, the RM would have an outer heat shield of reinforced carbon-carbon and a redundant layer of felt reusable surface insulation underneath in case of RCC failure. The RM comprised the top half of the Crew Module (CM), which comprised the RM and the rest of the lifting-body structure. The CM included living space for four crew members. In an emergency the RM separates from the rest of the CM. The RM would seat up to six crew members, with two to a row, and the CM has living space and provisions for four astronauts for 5–7 days. Extra-Vehicular Activities (EVAs) could be conducted from the CM, which could land on land or water and could be reused 5–10 times.

The mission module would be added to the bottom of the CEV for a lunar mission, and would be able to hold extra consumables and provide extra space for a mission of lunar duration. It would also provide extra power and communications capabilities, and include a docking port for the Lunar Surface Access Module (LSAM). On the bottom of the lunar CEV stack would be the Propulsion or Trans-Earth Injection Module (TEIM) which would provide for return to the Earth from the Moon. It would probably incorporate (according to Aviation Week) 2 Pratt & Whitney RL-10 engines. Together, the RM/CM, MM, and TEIM made up the Lockheed Martin lunar stack. The original idea was to launch the CM, MM, and TEIM on three separate Evolved Expendable Launch Vehicles (EELVs), with one component in each launch. This vehicle would need additional modules to reach lunar orbit and to land on the Moon. However, this plan was to be altered according to the CFI (Call for Improvements), described below.

Unlike the well-publicized Lockheed Martin CEV design, virtually no information was publicly available on the Boeing/Northrop Grumman CEV design. However, it is instructive to note that most publicly released Boeing designs for the canceled Orbital Space Plane (OSP) resembled the Apollo capsule. Given that Lockheed Martin's CEV design was in many ways a derivative of their OSP, it was possible that the Boeing CEV is a capsule rather than a lifting body or plane design.

Changes to original bids

NASA Constellation officials announcing the selected Orion contractor Aug. 31, 2006, at NASA Headquarters
NASA Constellation officials announcing the selected Orion contractor Aug. 31, 2006, at NASA Headquarters

Sean O'Keefe's strategy would have seen the CEV development in two distinct phases. Phase I would have involved the design of the CEV and a demonstration by the potential contractors that they could safely and affordably develop the vehicle. Phase I would have run from bid submissions in 2005 to FAST and downselect to one contractor. Phase II would have begun after FAST and involved final design and construction of the CEV. However, this schedule was unacceptably slow to Mike Griffin, and the plan was changed such that NASA will issue a "Call for Improvements" (CFI) after the release of the ESAS for Lockheed Martin and Boeing to submit Phase II proposals. NASA chose Lockheed Martin's consortium as the winning consortium on August 31, 2006. Therefore, the CEV bids submitted and described above are not necessarily representative of the final CEV design, as they will be changed in accordance with the CFI and any findings of the ESAS that are put into the CFI.

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Published in July 2009.

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