Science Fair Project Encyclopedia
Crew Exploration Vehicle
The Crew Exploration Vehicle (CEV) is NASA's proposed series of human spaceflight spacecraft, intended to replace the space shuttle system. The project to develop and test the CEV is Project Constellation.
As of 2004, NASA has not made any design decisions. However, it is likely that the CEV will follow the service and crew module design principle. Instead of the reusable spaceplane used in the space shuttle system, the crew module will be either a capsule similar to the one used in the Apollo, Gemini, Soyuz and Shenzhou systems, or a lifting body, similar to the X-38. The CEV will launch on an expendable launch system and carry crew to low Earth orbit, and perhaps more ambitiously in the future to the Moon, Mars, and other destinations.
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 RFP (Request For Proposal). The Final RFP was issued on March 1 2005 with the potential bidders being asked to answer by May 2 2005. However Michael Griffin, the new NASA Administrator, recently announced that this deadline might be delayed to allow for a reassessment of the CEV procurement strategy. This could lead to an overall acceleration of the program, in order to reduce the gap between Shuttle retirement and CEV availability.
One of the main goals of the new CEV are lunar expeditions.
NASA will choose two main contractor teams for the flyoff. Each team will have a complete design for the CEV and its launch vehicle. The teams will also have to develop a plan for their CEV to take part in the assembly of a lunar expedition in earth orbit. The two major teams announced are:
- Northrop Grumman associated with Boeing as subcontractor for the Spiral One, Alenia Spazio, ARES Corporation , Draper Laboratory and United Space Alliance
- Lockheed Martin associated with EADS SPACE Transportation, United Space Alliance , Honeywell, Orbital Sciences, Hamilton Sundstrand and Wyle Laboratories
Another announced team is t/Space, a consortium including such groups as Burt Rutan's Scaled Composites, Elon Musk's SpaceX, and Red Whittaker  of the Carnegie Mellon Robotics Institute. Some news reports in mid-March 2005, stemming from an interview with New Scientist have reported that t/Space intends to withdraw from the competition, citing a high paperwork burden; however, no announcement of a withdrawal has yet been made by t/Space.
Each contractor-led team will include subcontractors that will provide the lunar expedition astronauts with equipment, life support, rocket engines and onboard navigation systems. In the Earth orbit fly-offs, one complete CEV lunar mission design will compete against the other. NASA will choose the winner to build the final ships. Fly-offs are used by the U.S. Air Force to select military aircraft, this will be the first time that NASA has used this approach in awarding contracts.
Reusability is a valuable component, but initially not essential. The main choice will be what makes the most sense in designing the 21st century lunar craft.
Spiral development and schedule
NASA planners are focusing on a three-part plan for a return to the moon they call trade studies. NASA plans to have the winner of the fly-off competition design the CEV ships in a series of "spirals," or complete designs with spacecraft systems and subsystems:
- Exploration Spiral One (CEV Earth Orbit Capability) - Spiral 1 establishes the capability to test and checkout crew transportation system elements in Low Earth Orbit in preparation for future human exploration missions to the Moon. As new exploration elements necessary for future spirals are developed, they will be tested with the Spiral 1 CEV in the space environment to prepare for future exploration. The objective of crewed access to low earth orbit will be met by 2014.
- Exploration Spiral Two (Extended Lunar Exploration) - Spiral 2 establishes the capability to conduct human exploration missions on the surface of the Moon for extended durations. In this context, extended duration is defined as the capability to support the crew on the surface of the Moon for a minimum of four days. This objective will be met in the 2015-2020 timeframe.
- Exploration Spiral Three (Long Duration Lunar Exploration) - Spiral 3 establishes the capability to conduct routine human long duration missions on the surface of the Moon to test out technologies and operational techniques for expanding the human presence to Mars and beyond. Missions in Spiral 3 will extend in duration from those obtain in Spiral 2 up to several months to serve as an operational analog of future short stay Mars missions. This objective will be met after 2020.
- Exploration Spiral Four (Crew Transportation System Mars Flyby) – Encompasses the capabilities to conduct a Mars flyby mission using elements of the Human-Mars Crew Transportation System. Timeline - After 2020.
- Exploration Spiral Five (Human Mars Surface Campaign) – Encompasses the capabilities necessary to execute human Mars exploration missions. Timeline - After 2020.
NASA is also looking into building rockets with nuclear propulsion. This will not be part of the initial phase of building the Crew Exploration Vehicle.
NASA hopes to follow this schedule in development of the CEV:
- 2008 - The first prototype CEV is to be launched with a candidate launch vehicle. This is the fly-off called Flight Application of Spacecraft Technologies (FAST)
- 2008 - 3rd Quarter - NASA plans to select the final design for the lunar spacecraft and its mission mode.
- 2011 - First unmanned flight of CEV in earth orbit.
- 2014 - First manned flight of CEV in earth orbit.
- 2014 - First unmanned flight of lunar spacecraft design.
- 2015 - First manned flight of lunar spacecraft.
- 2015 - 2020 - First moon landing by astronauts in lunar spacecraft.
The proposal to create the CEV is partly a reaction to the Space Shuttle Columbia disaster, the Columbia Accident Investigation Board report and the White House's review of the American space program.
The CEV replaces the Orbital Space Plane (OSP) program.
- "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."
President Bush's budget request for Financial Year 2005 includes: "$428 million for Project Constellation ($6.6 billion over five years) to develop a new crew exploration vehicle." Budget for year 2005 has been confirmed by the Congress in November 2004.
The FY2006 budget request includes $753 million for continuing development of the CEV.
- NASA/Exploration Systems Mission Directorate Crew Exploration Vehicle solicitation
- Building Blocks of Tomorrow, Boeing page showing possible modular design of CEV
- t/Space Architecture Briefing to NASA
- President Bush Announces New Vision for Space Exploration Program - White House
- Administrator O'Keefe's Budget Presentation (1.9MB PDF) - NASA
- NASA Budget Lays Out CEV Spiral Development - Aerospace Daily
- Project Constellation weblog - James Burk
- Many happy returns - The Engineer, 09 February 2004 Boeing's concept design includes a reusable lunar lander.
- Exclusive: NASA begins moon return effort - UPI
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