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Orion (spacecraft)
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Orion is a spacecraft design currently under development by the United States space agency NASA. Each Orion spacecraft will carry a crew of four to six astronauts, and will be launched by the Ares I, a launch vehicle also currently under development. Both Orion and Ares I are elements of NASA's Project Constellation, which plans to send human explorers back to the Moon by 2020, and then onward to Mars and other destinations in the Solar System. On August 31, 2006, NASA awarded Lockheed Martin (LM) the contract to design, develop, and build Orion.
Orion will launch from Launch Complex 39 at Kennedy Space Center, the same launch complex that currently launches the Space Shuttle.
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Orion is a spacecraft design currently under development by the United States space agency NASA. Each Orion spacecraft will carry a crew of four to six astronauts, and will be launched by the Ares I, a launch vehicle also currently under development. Both Orion and Ares I are elements of NASA's Project Constellation, which plans to send human explorers back to the Moon by 2020, and then onward to Mars and other destinations in the Solar System. On August 31, 2006, NASA awarded Lockheed Martin (LM) the contract to design, develop, and build Orion.
Orion will launch from Launch Complex 39 at Kennedy Space Center, the same launch complex that currently launches the Space Shuttle. While shuttle operations continue from launch pad 39A, 39B is being readied for Ares launches. NASA will use Orion spacecraft for its human spaceflight missions after the last Shuttle orbiter is retired in 2010. The first Orion flight is scheduled for September 2014 with future flights to the International Space Station. If commercial orbital transportation services are unavailable, Orion will handle logistic flights to the Station. After that, Orion is to become a key component of human missions to the Moon and Mars.
Origin
On January 14, 2004, President George W. Bush announced the Orion spacecraft, known then as the Crew Exploration Vehicle (CEV), as part of the Vision for Space Exploration:
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 disaster, 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.
The Orion spacecraft described here should not be confused with theoretical spaceship designs from Project Orion in the 1950s in which nuclear explosions were to be used for propulsion. The Orion spacecraft described here uses a conventional (non-nuclear) propulsion system.
The name in itself is derived from the constellation of Orion, and was also used on the Apollo 16 Lunar Module that carried astronauts John W. Young and Charlie Duke to the Moon in April 1972.
Design
The Orion Crew and Service Module (CSM) stack consists of two main parts: a conical Crew Module (CM), and a cylindrical Service Module (SM) holding the spacecraft's propulsion system and expendable supplies. Both are based substantially on the Apollo Command and Service Modules (Apollo CSM) flown between 1967 and 1975, but include advances derived from the Space Shuttle program. "Going with known technology and known solutions lowers the risk," according to Neil Woodward, director of the integration office in the Exploration Systems Mission Directorate.
Crew Module
The Orion CM will hold four to six crew members, compared to a maximum of three in the smaller Apollo CM or seven in the larger Space Shuttle. Despite its conceptual resemblance to the 1960s-era Apollo, Orion's CM will use several improved technologies, including:
- An "autodock" feature, like those of Russian Progress spacecraft and the European Automated Transfer Vehicle, with provision for the flight crew to take over in an emergency. Previous American spacecraft (Gemini, Apollo, and Shuttle) have all required manual piloting for docking.
- Improved waste-management facilities, with a miniature camping-style toilet and the unisex "relief tube" used on the Space Shuttle (whose system was based on that used on Skylab) and the International Space Station (based on the Soyuz, Salyut, and Mir systems). This eliminates the use of the much-hated plastic "Apollo bags" used by the Apollo crews.
- A nitrogen/oxygen (N2/O2) mixed atmosphere at either sea level or slightly reduced pressure.
- Much more advanced computers than on previous manned spacecraft.
An important feature that may be introduced in the Orion CM is a new system employing a combination of parachutes and airbags for capsule recovery. This would allow retrieval of the Orion CM on land, like the Russian Soyuz descent module and its derivatives, and eliminate the expensive naval recovery fleet employed on all Mercury, Gemini, and Apollo flights. NASA may ultimately decide not to use this system, depending on the effect it has on weight. Water landings, otherwise only required in a launch abort scenario, may become the exclusive means of recovery for the Orion CM.
Another feature will be the partial reusability of the Orion CM. NASA aims to reuse each craft for up to ten flights, allowing it to build a fleet of both manned and unmanned Orion CMs. Both the CM and SM will be constructed of the aluminium lithium (Al/Li) alloy currently used on the Shuttle's External Tank, and the Delta IV and Atlas V rockets. This alloy is as strong as the Shuttle Orbiter's aircraft aluminium skin, but will make the spacecraft lighter than both its Apollo and Shuttle predecessors. The CM itself will be covered in the same nomex felt-like thermal protection blankets used on non-critical parts on the Shuttle such as the payload bay doors. The main thermal protection system (TPS) will be a derivative of the Phenolic Impregnated Carbon Ablator (PICA) heat shield developed for the Stardust return mission. The reusable recovery parachutes will be based on the parachutes used on both the Apollo spacecraft and the Space Shuttle Solid Rocket Boosters, and will also use the same nomex cloth for construction.
To allow the Orion spacecraft to service the International Space Station, and to mate with other Constellation vehicles, it will use a new Low Impact Docking System, a simplified version of the universal docking ring currently used on the Shuttle fleet, which itself was a Russian design that originated during the 1975 Apollo-Soyuz Test Project. Both the spacecraft and docking adapter will employ a Launch Escape System (LES) like that used in Mercury and Apollo, along with an Apollo-derived "Boost Protective Cover" (made of fiberglass), to protect the Orion CM from aerodynamic and impact stresses during the first 2½ minutes of ascent.
The Orion Crew Module (CM) is a 57.5° frustum shape, similar to that of the Apollo Command Module. As projected, the CM will be in diameter and in length, with a mass of about . It is to be built by the Lockheed Martin Corporation. It will have more than 2.5 times the volume of an Apollo capsule, which had an interior volume of , and will carry four to six astronauts.
Service Module
Like its Apollo predecessor, the Orion Service Module (SM) has a rough cylindrical shape, but unlike its Apollo predecessor, the new Orion SM will be larger in diameter, shorter, and lighter. It too will be constructed from the same Al-Li alloy as the Orion CM, and will feature a pair of deployable circular solar panels, similar in design to the solar panels on the Mars Phoenix lander, eliminating the need to carry fuel cells and the associated hardware—mainly tanks containing liquid hydrogen [LH2]—needed for their operation. The spacecraft's main propulsion system is an Aerojet AJ-10 rocket engine, derived from the second stage of the Delta II rocket, powered by hypergolic fuels, that are kept in helium pressured fuel cells. The SM Reaction Control System (RCS), the spacecraft's maneuvering thrusters, will also be pressure-fed, and will use the same propellants. NASA believes the SM RCS would be able to act as a backup for a trans-Earth injection (TEI) burn in case the main SM engine fails. The SM's twin spherical "slush" LOX tanks and a single tank of liquid nitrogen (LN2) will provide the crew with breathing air during the majority of the mission, while a "surge tank" located in the Orion CM itself will provide the crew with 2 to 4 hours (depending upon the number of crew members) of the same breathing air after SM jettison for the reentry phase of the flight. Lithium hydroxide (LiOH) cartridges will recycle the spacecraft's environmental system by "scrubbing" the carbon dioxide (CO2) exhaled by the astronauts from ship's air and adding fresh oxygen and nitrogen, which is then cycled back out into the system loop. Because of the elimination of the fuel cells and LH2 tanks, the Orion spacecraft will be required to carry tanks of potable water in both modules, which would provide drinking water for the crew, and (mixed with glycol), cooling water for the spacecraft's electronics. A closed-loop recycling system, using both waste water and urine, will allow the replenishment of the water coolant system, and will be identical to those units used on both the Mir and International Space Stations.
The SM also mounts the spacecraft's waste heat management system (its radiators) and the aforementioned solar panels. These panels, along with backup batteries located in the Orion CM, will provide in-flight power to the ship's systems. The voltage, 28 volts DC, is similar to that used on the Apollo spacecraft during flight.
Like the Orion crew module, the Orion service module will be encapsulated by a fiberglass shroud that would be jettisoned at the same time the LES/Boost Protective Cover, which would take place roughly 2½ minutes after launch (30 seconds after the solid rocket first stage is jettisoned). Prior to the "Orion 606" redesign, the Orion SM resembled a squat, enlarged version of the Apollo Service Module. The new "Orion 606" SM design retains the 5-meter width for the attachments of the Orion SM with the Orion CM, but utilizes a Soyuz-like service module design that allows Lockheed Martin to make the vehicle lighter in weight and permitting the attachment of the circular solar panels at the module's mid-points, like that of the Soyuz, instead of at the base near the spacecraft/rocket adapter, which may subject the panels to damage.
The Orion service module (SM) is projected comprising a cylindrical shape, having a diameter of 5.03 m (16.50 ft) and an overall length (including thruster) of 4.78 m (15.68 ft). With solar panels extended, span is 17.00 m (55.00 ft). The projected empty mass is 3,700 kg (8,000 lb), fuel capacity is 8,300 kg (18,000 lb).
Launch Abort System
In the event of an emergency on the launch pad or during ascent, a launch escape system called the Launch Abort System (LAS) will separate the Crew Module from the launch vehicle using a solid rocket-powered launch abort motor (AM), which is more powerful than the Atlas 109-D booster that launched astronaut John Glenn into orbit in 1962. There are two other propulsion systems in the LAS stack - the attitude control motor (ACM) and the jettison motor (JM). On July 10, 2007, Orbital Sciences -- the prime contractor for the LAS -- awarded Alliant Techsystems (ATK) a $62.5 million sub-contract to, "design, develop, produce, test and deliver the launch abort motor." ATK, which has the prime contract for the first stage of the Ares I rocket, intends to use an innovative "reverse flow" design for the motor. On July 9, 2008 NASA announced that ATK has completed a vertical test stand at a facility in Promontory, Utah to test launch abort motors for the Orion spacecraft. Another long-time space motor contractor, Aerojet, was awarded the jettison motor design and development contract for the LAS. As of September 2008 Aerojet has, along with team members Orbital Sciences, Lockheed Martin and NASA, successfully demonstrated two full-scale test firings of the jettison motor. This motor is important to every flight in that it functions to pull the LAS tower away from the vehicle after a successful launch. The motor also functions in the same manner for an abort scenario.
Another idea, recently floated by NASA, would see the LAS tower being replaced with the so-called Max Launch Abort System (MLAS), in which four existing solid-rocket motors, integrated into the boost protective cover and placed at 90° intervals, would fire and pull the Orion crew module away from an Ares I rocket in the event of a launchpad or in-flight abort during the first 2½ minutes of launch. If implemented in place of the LAS, the MLAS would allow NASA to reduce further weight of the Orion/Ares I stack (which has been tagged by critics as being overweight) and the design, which is shaped like a bullet, would reduce stresses on both the spacecraft and the launch vehicle, as well as reducing the overall height by 20-25 feet.
Design revisions and updates
July 2006 design revisions
In late July 2006 NASA's second design review resulted in major changes to the spacecraft design. Originally, NASA wanted to use liquid methane (LCH4) as the SM fuel, but due to the infancy of oxygen/methane-powered rocket technologies and the need to launch the Orion by 2012, the switch to hypergolic propellants was mandated in late July 2006. This switch will allow NASA to man-rate the Orion and Ares I stack by no later than 2011 , and eliminate one potential cause of the gap between the Shuttle's retirement in 2010 and the first manned Orion flight.
April 2007 contract revision
On April 20, 2007 NASA and Lockheed Martin signed a modification to the Orion contract. The updated contract adds two years to the Orion project design phase, adds two test flights of Orion's launch abort system, and deletes from the initial design phase production of a pressurized cargo carrier for the International Space Station.
May 2007 design update
An article in "Aerospace Daily & Defense Report" indicates that in the latest Orion design revision, called configuration "606" by LM, the service module will have exterior panels that are jettisoned shortly after the second stage engine of the Ares I ignites. This configuration will save 1,000 pounds of mass compared with the prior "605" configuration.
August 2007 design update
On August 5, a report surfaced stating that the airbag landing system was removed from the next Orion design cycle ("607") in a weight saving measure, opting to return to an Apollo-style splashdown for the vehicle's end of mission. Scott Horowitz, head of the Exploration Systems Mission Directorate, denied making a final decision on the Orion CM recovery method but admitted that NASA is studying the possibility of removing the land recovery option.
Abort tests
ATK successfully completed the first Orion launch abort test on November 20, 2008. The abort motor will provide a half-million pounds of thrust for an emergency on the launch pad or during the first 300,000 feet of the rocket's climb to orbit. The test firing was the first time a motor with reverse flow propulsion technology at this scale has been tested.
This abort test firing brought together a series of motor and component tests conducted in 2008 as a preparation for the next major milestone, a full-size mock-up or boilerplate test scheduled for the spring of 2009.
Criticism
Acquisition strategy
The Space Frontier Foundation has asserted that the $3.9 billion initial phase of the Orion contract essentially duplicates the functionality of NASA's $500 million Commercial Orbital Transportation Services (COTS) program. Additionally, NASA's contract with Lockheed Martin is a cost-plus contract, a contracting method which has been criticized for being prone to cost overruns and delays, while contractors in the COTS only receive payment for successes. The U.S. Government Accountability Office (GAO) is also critical of NASA, saying, "NASA's current acquisition strategy for the CEV places the project at risk of significant cost overruns, schedule delays, and performance shortfalls because it commits the government to a long-term product development effort before establishing a sound business case."
Exploration Systems Architecture Study
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.
Competition and proposals
Testing
Environmental testing
NASA will perform environmental testing of Orion from 2007 to 2011 at the Glenn Research Center Plum Brook Station in Sandusky, Ohio. The Center's Space Power Facility is the world's largest thermal vacuum chamber.
Abort Flight Test (AFT)
NASA will perform a series of six Abort Flight Tests between the fall of 2008 and the end of 2011 at the United States Army's White Sands Missile Range (WSMR), New Mexico. The Orion AFT subproject includes two pad abort tests and four ascent abort tests. Three of the four ascent aborts are planned to be flown from a special test launch vehicle, the Orion Abort Test Booster, the fourth one being performed with Ares I-Y. The Orion Abort Flight Tests are similar in nature to the Little Joe II tests performed at WSMR between September 1963 and January 1966 in support of the development of the Apollo program's Launch Escape System.
Schedule
NASA hopes to follow this schedule in development of the Orion:
- 2006–2007 — Engineering review of selected design
- 2008 (Sep) — PA-1 (Pad Abort-1) unmanned pad abort test.
- 2009 (Sep) — AA-1 (Ascent Abort-1) unmanned ascent abort test (transonic)
- 2010 (Spring) — PA-2 unmanned pad abort test
- 2010 (August) — AA-2 unmanned ascent abort test (Max Q)
- 2011 (February) — AA-3 unmanned ascent abort test (low-altitude tumble test)
- 2012 (September) — Ares I-Y unmanned ascent abort test (high altitude)
- 2012 — First unmanned flight of Orion in Earth orbit.
- 2014 (September) — First manned flight of Orion in Earth orbit.
- 2015–2018 — First unmanned flight of Altair.
- 2016–2018 First manned flight of Altair.
- 2019 First manned lunar landing with Orion/Altair system.
- 2020 start of planning for Mars missions
- 2037 Possible date of manned arrival on Mars hinted at by former NASA administrator, Michael Griffin
NASA initially established that it would initiate a phased retirement of the Space Shuttle, which would have begun with the retirement of one orbiter, Atlantis, in 2008. This decision was later changed; all three remaining shuttles would keep flying until 2010. In the meantime, NASA engineers would work to upgrade the current launch facilities to work with the next generation shuttle-derived launch vehicles.
Such a plan would allow lunar mission development to begin much earlier than currently planned, as additional funding will be available earlier.
Possibilities for future CEV development
After the replacement of Sean O'Keefe, NASA's procurement schedule and strategy has 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. The actions Griffin has taken as administrator support the goals of the plan.
According to the executive summary, the study is built around "a staged approach to human exploration beyond low Earth orbit (LEO)." It recommends that Project Constellation be carried out in three distinct phases, called "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."
Stage I
Rather than designing a CEV solely for the earliest lunar landing possible, the report recommends developing the CEV in two Blocks. The Block I CEV would be suitable for LEO missions only and would be developed as quickly as possible to avoid the gap between the currently scheduled Shuttle retirement in 2010 and CEV flights starting in 2014. It would carry a crew of 4–6 astronauts. The report recommends the development of a shuttle-derived CEV launch vehicle based on the "Shuttle Solid Rocket Motor with a new liquid propellant upper stage" for CEV launch, rather than man-rating an EELV. This approach would allow the advantages of using a proven, man-rated design (the Solid Rocket Motor), plus the ability to continue using Shuttle infrastructure to support CEV operations.
Indeed, as described above, the upcoming Exploration Systems Architecture Study is thought to contain an endorsement of exactly this option — the construction of an SRM-based SDLV, plus a heavy-lift launch vehicle derived from the Shuttle, in addition to options for expediting CEV development to permit earlier manned flight. Therefore, the idea that the Planetary Society report could shed light on future CEV development is supported by these new developments. In other words, the very recommendations contained in the report for the beginning of Stage I — namely, the expedited CEV development and the SRM-derived launch vehicle — appear to have materialized.
Under the rest of Stage I, the Shuttle would be retired as soon as possible after completing the "U.S. Core Complete" configuration of the International Space Station, an option that also appears to have gained support within NASA and the Bush administration. The report makes no specific mention of a manned Hubble Space Telescope servicing mission, although Administrator Griffin has instructed Hubble managers at NASA Goddard Space Flight Center to make preparations for such a mission, and the report refers to Hubble as "world-class astronomy". The report suggests the use of expendable launchers, either foreign vehicles such as the Ariane and Proton, or a new Shuttle-derived, heavy-lift launch vehicle to complete the ISS after Shuttle retirement. The Block I CEV could also act as an ISS Crew Return Vehicle, allowing crews of more than three to be supported. Stage I is to be implemented by 2010.
Stage II
Under Stage II, a new Block II CEV would be developed, suitable for interplanetary flight. The report states that the new CEV should keep the same mold lines as the Block I, making the selection of an appropriate Block I CEV extremely important to the successful implementation of the plan. The report states that the Block II CEV would need to have capability to conduct interplanetary cruises of at least several months in duration. It suggests the development of other modules, specifically modules called "Hab", "Lab", "Propulsion", and "Consumables" to support longer-duration flights, possibly to be carried onboard Ares V to LEO for Orion to pick-up. The use of ISS module derivatives for the Hab and Lab modules is suggested but not explicitly endorsed.
Four destinations are suggested for CEV exploration in Stage II. They are (probably, although not necessarily) in the order that they would be visited:
The goal would be to conduct flights to each of these destinations but without a human-rated lander for the Moon and Mars. The use of SEL2 is described as important to demonstrate the capability of servicing future space telescopes (such as the James Webb Space Telescope) there and also for staging interplanetary flights. After the flights to SEL2, a flight to a NEO could be attempted; due to its extremely low surface gravity a landing module would not be needed and the astronauts could "walk" on it with MMU-like equipment. Finally, a mission to orbit Mars and possibly land on its moons is suggested. All these flights would be accomplished with one CEV design supported by the various modules, as necessary. Stage II would take place from about 2015 onward. However, according to the current descriptions of the ESAS, a landing on the Moon appears to be the first priority of Project Constellation and will occur by 2018.
Stage III
In Stage III, human-rated landers are developed to allow landings on both the Moon and Mars. Since the Block II CEV should be capable of flights to both these destinations, lunar and Mars landings could begin simultaneously, with the experience gained from exploring the four destinations referenced in Stage II. These landings would begin in 2020.
Summary
Although Orion development is in an early stage and it remains to be seen what form it will finally take, NASA is apparently taking exactly the steps recommended for the implementation of Stage I of the report. Therefore, it is likely that the three-stage plan suggested in this report will be the plan for the actual Project Constellation. Although it appears that the plan will not be followed exactly, it is possible that elements of it will still be used as a baseline for Constellation exploration strategies (for example, Stage I appears to have become a NASA strategy). The plan does not allow for lunar landings as early as 2015, as suggested in the Bush vision, but does permit an early Mars landing in 2020, contemporaneous with lunar landings by that date.
Building 9 at the Johnson Space Center in Houston, Texas contains a full-scale mock-up simulator of the Orion CM. As of July 26, 2006, internal components were being fitted. A mock-up of the Crew Module is also on display at the United States Space and Rocket Center in Huntsville, Alabama.
Funding
President Bush's budget request for Fiscal Year 2005 included "$428 million for Project Constellation ($6.6 billion over five years) to develop a new crew exploration vehicle". The budget for FY2005 was confirmed by the Congress in November 2004 with full funding for the CEV.
The FY2006 budget request includes $753 million for continuing development of the CEV. As of 2005 the total development costs of the CEV are estimated at $15 billion.
Lockheed Martin's contract for the initial "Schedule A" part of the Orion project, awarded on August 31, 2006 and running through 2013, is worth $3.9 billion. Additional development options in the "Schedule B" part of the contract could be worth up to another $3.5 billion.
Although to date the exploration systems have received full funding and a House endorsement, there is a possibility that rising Shuttle return to flight costs will make funding of CEV development extremely difficult. There has been discussion of either obtaining a special supplemental from Congress to pay for the extra Shuttle costs, or of involving private industry in CEV development and operations. The total funding of Project Constellation through 2025, inflation-adjusted and without any other increases to NASA's budget, is estimated at $210 billion; the ESAS estimates the cost of the program through that date at being only $7 billion more, at $217 billion. This cost may in fact end up lower as it includes developing new engines for the EDS instead of the newer idea of using J-2 derivatives.
Orion nomenclature (as of December 2007)
- Orion - Crew/Service Module (CSM) manned/unmanned multi-role spacecraft.
- Altair - Lunar Surface Access Module (LSAM), the manned/unmanned lunar logistics vehicle.
- Ares I - ("The Stick") Medium-lift crew/cargo launch vehicle.
- Ares IV - Medium-heavy lift launch vehicle announced in February, 2007.
- Ares V - Heavy-lift cargo launch vehicle.
See also
External links
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