Crew Exploration Vehicle

The Crew Exploration Vehicle (CEV) was the conceptual component of the U.S. NASA Vision for Space Exploration that later became known as the Orion spacecraft. The Orion CEV was part of NASA's Constellation Program to send human explorers back to the Moon, and then onward to Mars and other destinations in the solar system.

Official planning for the vehicle began in 2004, with the final Request For Proposal issued on March 1, 2005, to begin a design competition for the vehicle. For the later design and construction phases, see Orion (spacecraft). NASA has posted project status notes at the website, under the name "Orion Crew Exploration Vehicle" (see External links, below).

CEV Lockheed Martin
CEV initial concept in Lockheed Martin design, showing delta-wing crew module (at right), with a mission module and propulsion stage (with rocket engines) for interplanetary flight.
File- Current 2009 Cev design
Orion (spacecraft), as a later design, after the initial plans for the Crew Exploration Vehicle led to development of the Orion.


The concept for the vehicle was officially announced in a speech given by George W. Bush at NASA Headquarters on January 14, 2004.[1] 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 (RFP). The Final RFP was issued on March 1, 2005,[2] 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 Michael D. Griffin 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.[3]

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.[4] 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.[5] 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.[6]

On August 31, 2006, NASA announced that the contract to design and develop the Orion was awarded to Lockheed Martin Corp.[7] According to Bloomberg News, five analysts it surveyed prior to the award announcement tipped the Northrop team to win.[8] 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.[8] 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.[9]

Lockheed Martin plans to manufacture the manned spacecraft at facilities in Texas, Louisiana, and Florida.[10]


Original designs

Lockheed's proposed craft was a small Space 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 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.[11]

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. It was possible that the Boeing CEV is a capsule rather than a lifting body or plane design.[12]

Changes to original bids

Orion briefing model
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 (by Sept 2008) 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.[13] NASA chose Lockheed Martin's consortium as the winning consortium on August 31, 2006.[14] 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.


  1. ^ "President Bush Announces New Vision for Space Exploration Program". NASA.
  2. ^ NASA (2005-03-01). "Crew Exploration Vehicle, Solicitation SOL NNT05AA01J". Archived from the original on 2009-01-17. Retrieved 2006-09-09.
  3. ^ Dunn, Marcia (2006-05-13). "NASA Chief Pushes for Shuttle's Replacement". Retrieved 2007-03-03.
  4. ^ NASA HQ (2005-06-13). "NASA Selects Contractors for Crew Exploration Vehicle Work". NASA Press Release 05-146. Archived from the original on 2006-08-27. Retrieved 2006-09-09.
  5. ^ "Category: CEV, OSP, SDLV, and ISTP Archives". NASA Watch. Archived from the original on 2005-10-18.
  6. ^ Schneider, Mike (2006-08-26). "Astronaut lets name of new spaceship slip". Houston Chronicle. Retrieved 2007-03-03.
  7. ^ "NASA Selects Lockheed Martin To Be Orion Crew Exploration Vehicle Prime Contractor" (Press release). NASA. 2006-08-31. Retrieved 2006-08-31.
  8. ^ a b Lococo, Edmond; Demian McLean (2006-08-31). "Lockheed Beats Northrop for $3.9 Billion NASA Award (Update4)". Bloomberg News. Retrieved 2006-09-05.
  9. ^ Morris, Jefferson (2006-09-07). "CEV Decision Document Ranks LM Ahead In Mission Suitability, Cost, Past Performance". Aerospace Daily & Defense Report. Retrieved 2006-09-09.
  10. ^ "Lockheed Martin Selected by NASA for Orion Crew Exploration Vehicle" (Press release). Lockheed Martin. 2006-08-31. Retrieved 2006-09-06.
  11. ^ Coburn, Davin (1 June 2005). "Lockheed Unveils Shuttle Replacement - A PM Exclusive". Popular Mechanics. Retrieved 2012-06-30.
  12. ^ Image Display
  13. ^ "Crew Exploration Vehicle (CEV) Procurement". NASA. 2005-05-16. Archived from the original on 2008-04-03. Retrieved 2007-03-03.
  14. ^ Merle, Renae (2006-09-01). "Lockheed Wins Contract to Build NASA's New Spaceship". The Washington Post. Retrieved 2007-03-03.

External links


AVCOAT 5026-39 is a NASA code for a specific ablative heat shield material created by Avco (acquired by Textron in 1984).

It is an epoxy novolac resin with special additives in a fiberglass honeycomb matrix. In fabrication, the empty honeycomb is bonded to the primary structure and the resin is gunned into each cell individually.

Ames Research Center

The Ames Research Center (ARC), also known as NASA Ames, is a major NASA research center at Moffett Federal Airfield in California's Silicon Valley. It was founded in 1939 as the second National Advisory Committee for Aeronautics (NACA) laboratory. That agency was dissolved and its assets and personnel transferred to the newly created National Aeronautics and Space Administration (NASA) on October 1, 1958. NASA Ames is named in honor of Joseph Sweetman Ames, a physicist and one of the founding members of NACA. At last estimate NASA Ames has over US$3 billion in capital equipment, 2,300 research personnel and a US$860 million annual budget.

Ames was founded to conduct wind-tunnel research on the aerodynamics of propeller-driven aircraft; however, its role has expanded to encompass spaceflight and information technology. Ames plays a role in many NASA missions. It provides leadership in astrobiology; small satellites; robotic lunar exploration; the search for habitable planets; supercomputing; intelligent/adaptive systems; advanced thermal protection; and airborne astronomy. Ames also develops tools for a safer, more efficient national airspace. The center's current director is Eugene Tu.The site is mission center for several key current missions (Kepler, the Lunar Crater Observation and Sensing Satellite (LCROSS) mission, Stratospheric Observatory for Infrared Astronomy (SOFIA), Interface Region Imaging Spectrograph) and a major contributor to the "new exploration focus" as a participant in the Orion crew exploration vehicle.

Austere Human Missions to Mars

Austere Human Missions to Mars is a concept for a human mission to Mars by the United States space agency, NASA. Released in 2009, it proposed a modified and even less costly version of Design Reference Architecture (DRA) 5.0, itself a combination of nearly 20 years of Mars planning design work. The mission profile was for a conjunction class with a long surface stay, pre-deployed cargo, aerocapture and propulsive capture, and some in-situ resource production. As of 2015, the concept has not yet been adapted to the Space Launch System that replaced NASA's Constellation program in 2011.


CEV may stand for:

European Volleyball Confederation (French: Confédération européenne de volleyball), the continental European volleyball governing body

Certified Video Engineer, a professional title regulated by the Society of Broadcast Engineers

Chemins de fer électriques Veveysans, a Swiss railway company

Contemporary English Version, a translation of the Bible into English

Crew Exploration Vehicle, NASA's proposed human spaceflight system, now known as Orion

Combat engineering vehicle, armoured vehicles supporting battlefield engineering works

M728 combat engineer vehicle, a combat engineer vehicle mounted on a tank chassis

Closed-eye visualization, a class of hallucination

Coherent Extrapolated Volition, an approach to friendly artificial intelligence

Constant elasticity of variance model, a pricing model

Equivalent carbon content, also called "carbon equivalent value", a property of alloy steels

Centre d'essais en vol, a flight testing centre in Brétigny-sur-Orge, France

European Volunteer Centre

Venezuelan Episcopal Conference, a Venezuelan Catholic archdiocesan organization

Cleon Lacefield

T. Cleon Lacefield is Lockheed Martin vice president and Orion program manager.With his Lockheed Martin team in Denver and Houston, he won the CEV / Orion development contract from NASA in September 2006.

Constellation program

The Constellation Program (abbreviated CxP) is a cancelled manned spaceflight program developed by NASA, the space agency of the United States, from 2005 to 2009. The major goals of the program were "completion of the International Space Station" and a "return to the Moon no later than 2020" with a crewed flight to the planet Mars as the ultimate goal. The program's logo reflected the three stages of the program: the Earth (ISS), the Moon, and finally Mars—while the Mars goal also found expression in the name given to the program's booster rockets: Ares (the Greek equivalent of the Roman god Mars). The technological aims of the program included the regaining of significant astronaut experience beyond low Earth orbit and the development of technologies necessary to enable sustained human presence on other planetary bodies.Constellation began in response to the goals laid out in the Vision for Space Exploration under NASA Administrator Sean O'Keefe. O'Keefe's successor, Michael D. Griffin, ordered a complete review, termed the Exploration Systems Architecture Study, which reshaped how NASA would pursue the goals laid out in the Vision for Space Exploration, and its findings were formalized by the NASA Authorization Act of 2005. The Act directed NASA to "develop a sustained human presence on the Moon, including a robust precursor program to promote exploration, science, commerce and US preeminence in space, and as a stepping stone to future exploration of Mars and other destinations." Work began on this revised Constellation Program, to send astronauts first to the International Space Station, then to the Moon, and then to Mars and beyond.Subsequent to the findings of the Augustine Committee in 2009 that the Constellation Program could not be executed without substantial increases in funding, on February 1, 2010, President Barack Obama announced a proposal to cancel the program, effective with the passage of the U.S. 2011 fiscal year budget. He later announced changes to the proposal in a major space policy speech at Kennedy Space Center on April 15, 2010. Obama signed the NASA Authorization Act of 2010 on October 11, which shelved the program, with Constellation contracts remaining in place until Congress would act to overturn the previous mandate. In 2011, NASA announced that it had adopted the design of its new Space Launch System.

Exploration Systems Architecture Study

The Exploration Systems Architecture Study (ESAS) is the official title of a large-scale, system level study released by the National Aeronautics and Space Administration (NASA) in November 2005 in response to American president George W. Bush's announcement on January 14, 2004 of his goal of returning astronauts to the Moon and eventually Mars — known as the Vision for Space Exploration (and unofficially as "Moon, Mars and Beyond" in some aerospace circles, though the specifics of a manned "beyond" program remain vague).

Juan R. Cruz

Juan R. Cruz, Ph.D., (born: January 5, 1946) is a Puerto Rican aerospace engineer who played an instrumental role in the design and development of the Mars Exploration Rover (MER) and Mars Science Laboratory (MSL) parachute.

Jupiter (rocket family)

The Jupiter family of Super heavy-lift launch vehicles was part of the proposed DIRECT Shuttle-Derived Launch Vehicle architecture. It was intended to be the alternative to the Ares I and Ares V rockets which were under development for the United States National Aeronautics and Space Administration's (NASA) Project Constellation.

Some of the major benefits of re-using as much hardware and facilities from the Space Shuttle program as possible to minimize costs, take advantage of the experience with existing hardware and preserve the workforce after the Space Shuttle's retirement.

Max Launch Abort System

The Max Launch Abort System (MLAS) was a proposed alternative to the Maxime Faget-invented "tractor" launch escape system (LES) that was planned for use by NASA for its Orion spacecraft in the event an Ares I malfunction during launch required an immediate abort.

Designed by NASA engineers and reported on the website on December 6, 2007, the proposed MLAS used four existing Huntsville-built Thiokol solid-rocket motors (built in 1988) placed at 90° intervals within the Orion's bullet-shaped fairing. The fairing was originally designed to protect the Orion spacecraft from aerodynamic stresses during launch, and to provide an interface between the spacecraft's crew module with the LES.

The MLAS was designed with the aim of reducing the height of the Orion/Ares I stack while also reducing weight and center-of-gravity issues of a traditional LES. The bullet-shaped MLAS was also expected to provide better aerodynamic qualities during the first two minutes of flight, reducing stresses when the vehicle encounters the "max Q" region of hypersonic flight. The MLAS was also expected to simplify production, as existing hardware would be employed.

There are several drawbacks to MLAS. First, the bullet-shaped protective cover would have to be modified and reinforced to allow for the use of the solid-rocket motors, something not needed with the LES, which bolts on top of the LIDS docking ring assembly. Second, the necessity to fire multiple motors (LES uses one motor and multiple nozzles) simultaneously for an abort decreases the theoretical reliability of the launch abort system by introducing more failure modes.

Like the existing LES, the MLAS would provide protection to the Orion spacecraft crew during the first ​2 1⁄2 minutes of flight, with the MLAS being jettisoned, along with the service module's fairing panels, after the solid-rocket first stage was jettisoned. If implemented, the Orion/Ares I stack would have resembled the towerless Gemini-Titan stack used between 1965–1966, in which ejection seats were used as the primary form of escape for the astronauts who flew on the ten Gemini missions.

The MLAS concept was dropped with the transformation of the Crew Exploration Vehicle into the Orion Multi-Purpose Crew Vehicle, and the switch of the launch vehicle from Ares I (with its perennial underperformance) to the Delta IV Heavy or Space Launch System.


Nomex is a flame-resistant meta-aramid material developed in the early 1960s by DuPont and first marketed in 1967.

Nonequilibrium Gas and Plasma Dynamics Laboratory

The Nonequilibrium Gas and Plasma Dynamics Laboratory (NGPDL) at the Aerospace Engineering Department of the University of Michigan is headed by Professor Iain D. Boyd and performs research of nonequilibrium gases and plasmas involving the development of physical models for various gas systems of interest, numerical algorithms on the latest supercomputers, and the application of challenging flows for several exciting projects. The lab places a great deal of emphasis on comparison of simulation with external experimental and theoretical results, having ongoing collaborative studies with colleagues at the University of Michigan such as the Plasmadynamics and Electric Propulsion Laboratory, other universities, and government laboratories such as NASA, United States Air Force Research Laboratory, and the United States Department of Defense.

Current research areas of the NGPDL include electric propulsion, hypersonic aerothermodynamics, flows involving very small length scales (MEMS devices), and materials processing (jets used in deposition thin films for advanced materials). Due to nonequilibrium effects, these flows cannot always be computed accurately with the macroscopic equations of gas dynamics and plasma physics. Instead, the lab has adopted a microscopic approach in which the atoms/molecules in a gas and the ions/electrons in a plasma are simulated on computationally using a large number of model particles within sophisticated Monte Carlo methods. The lab has developed a general 2D/axi-symmetric/3D code, MONACO, for simulating nonequilibrium neutral flows that can run either on scalar workstations or in a parallel computing environment.

The lab also has developed a general 2D/axi-symmetric/3D code, LeMANS, to numerically solve the Navier-Stokes equations using computational fluid dynamics when the Knudsen number is sufficiently small. This allows lab members to explore flows that would otherwise be too computationally expensive with a particle method. Work is currently being done to combine the two codes into a hybrid that uses MONACO when the flow is in the collisional nonequilibrium regime and LeMANS when the flow can be considered continuous.

Current and past plasma and nonequilibrium flow projects include simulation of ion thrusters, Hall effect thrusters, and pulsed plasma thrusters) as well as numerous NASA contracts to study reentry aerothermodynamics for space vehicles, including the Crew Exploration Vehicle. Other plasma research includes modeling wall ablation from directed energy weapons and the plasma-propellant interaction in electrothermal chemical guns.

Operations and Checkout Building

The Neil Armstrong Operations and Checkout Building (previously known as the Manned Spacecraft Operations Building) is a historic building on Merritt Island, Florida, United States. The five-story structure is in the Industrial Area of NASA's Kennedy Space Center. Its facilities include the crew quarter dormitories for astronauts, and suit-up preparations prior to their flights. The other facility is a large spacecraft workshop used for manufacturing and checking activities on manned spacecraft. On January 21, 2000, it was added to the U.S. National Register of Historic Places.

Orbital Space Plane Program

The Orbital Space Plane (OSP) program was a NASA spaceplane concept in the early 2000s designed to support the International Space Station requirements for crew rescue, crew transport and contingency cargo such as supplies, food and other needed equipment.

With the initiation of the Constellation program in 2004, NASA transferred the knowledge gained on the OSP to the development of Crew Exploration Vehicle, an Apollo-style capsule with separate crew and service modules.

Orion (spacecraft)

The Orion Multi-Purpose Crew Vehicle (Orion MPCV) is an American-European interplanetary spacecraft intended to carry a crew of four astronauts to destinations at or beyond low Earth orbit (LEO). Currently under development by the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) for launch on the Space Launch System, Orion is intended to facilitate human exploration of the Moon, asteroids and of Mars and to retrieve crew or supplies from the International Space Station if needed.The Orion MPCV was announced by NASA on May 24, 2011, and is currently under development. Its design is based on the Orion Crew Exploration Vehicle from the cancelled Constellation program. It has two main modules. The Orion command module is being built by Lockheed Martin at the Michoud Assembly Facility in New Orleans. The Orion service module, provided by the European Space Agency, is being built by Airbus Defence and Space.

The MPCV's first test flight (uncrewed), known as Exploration Flight Test 1 (EFT-1), was launched atop a Delta IV Heavy rocket on December 5, 2014, on a flight lasting 4 hours and 24 minutes, landing at its target in the Pacific Ocean at 10:29 Central (delayed from the prior day due to technical and weather problems). The first mission to carry astronauts is not expected to take place until 2023 at the earliest, although NASA officials have said that their staff is working toward an "aggressive internal goal" of 2021. However, a July 2016 Government Accountability Office report cast doubt on even the 2023 launch date, suggesting it may slip up to six months. The report gave only a 40% confidence in the 2021 launch date, and suggested the aggressive goal may be counterproductive to the program.

Orion service module

The Orion service module is the service module component of the Orion spacecraft, serving as its primary power and propulsion component until it is discarded at the end of each mission. In January 2013, NASA announced that the European Space Agency (ESA) will contribute the service module for Exploration Mission 1, replacing the previous design. Based on ESA's Automated Transfer Vehicle (ATV), the new design is also known as the European service module (ESM).

The service module supports the crew module from launch through separation prior to reentry. It provides in-space propulsion capability for orbital transfer, attitude control, and high altitude ascent aborts. It provides the water and oxygen needed for a habitable environment, generates and stores electrical power, and maintains the temperature of the vehicle's systems and components. This module can also transport unpressurized cargo and scientific payloads.


The RS-18 is a reconfigured version of the Rocketdyne Lunar Module Ascent Engine (LMAE), modified to burn liquid oxygen (LOX) and liquid methane (CH4) for NASA's Exploration Systems Architecture Study (ESAS) engine testing in 2008.

Reentry capsule

A reentry capsule is the portion of a spacecraft which returns to Earth following a space flight. The shape is determined partly by aerodynamics; a capsule is aerodynamically stable falling blunt end first, which allows only the blunt end to require a heat shield for atmospheric entry. Its shape has also been compared to that of an old-fashioned automobile's headlight. A manned capsule contains the spacecraft's instrument panel, limited storage space, and seats for crew members. Because a capsule shape has little aerodynamic lift, the final descent is via parachute, either coming to rest on land, at sea, or by active capture by another aircraft. In contrast, the development of spaceplane reentry vehicles attempts to provide a more flexible reentry profile.

Vision for Space Exploration

The Vision for Space Exploration (VSE) was a plan for space exploration announced on January 14, 2004 by President George W. Bush. It was conceived as a response to the Space Shuttle Columbia disaster, the state of human spaceflight at NASA, and as a way to regain public enthusiasm for space exploration. It was replaced by the space policy of the Barack Obama administration in June 2010.

Flight tests
Launch sites
Abort systems
Related topics
Crewed lunar spacecraft
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