International Space Station The International Space Station (ISS) is the largest Modular design, modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos ( ...

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedi ...

expeditions Exploration refers to the historical practice of discovering remote lands. It is studied by geographers and historians. Two major eras of exploration occurred in human history: one of convergence, and one of divergence. The first, covering most ...

International Space Station program The International Space Station programme is tied together by a complex set of legal, political and financial agreements between the fifteen nations involved in the project, governing ownership of the various components, rights to crewing and ...

SpaceX Space Exploration Technologies Corp. (SpaceX) is an American spacecraft manufacturer, launcher, and a satellite communications corporation headquartered in Hawthorne, California. It was founded in 2002 by Elon Musk with the stated goal of ...

Crew Dragon Dragon 2 is a class of partially reusable spacecraft developed and manufactured by American aerospace manufacturer SpaceX, primarily for flights to the International Space Station (ISS). SpaceX has also launched private missions such as In ...

Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and ...

Boeing Starliner The Boeing CST-100 Starliner
is a class of two partially The spacecraft are owned and operated by the vendor, and crew transportation is provided to NASA as a commercial service. Each mission sends up to four astronauts to the ISS, with an option for a fifth passenger available. Operational flights occur approximately once every six months for missions that last for approximately six months. A spacecraft remains docked to the ISS during its mission, and missions usually overlap by at least a few days. Between the retirement of the

Space Shuttle The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program na ...

in 2011 and the first operational CCP mission in 2020, NASA relied on the

Soyuz program The Soyuz programme ( , ; russian: link=no, Союз , meaning "Union") is a human spaceflight programme initiated by the Soviet Union in the early 1960s. The Soyuz spacecraft was originally part of a Moon landing project intended to put a ...

to transport its astronauts to the ISS. A Crew Dragon spacecraft is launched to space atop a

Falcon 9 Block 5 Falcon 9 Block 5 is a partially reusable two-stage-to-orbit medium-lift launch vehicle designed and manufactured in the United States by SpaceX. It is the fifth version of Falcon 9 Full Thrust, powered by SpaceX Merlin engines burning rocket-g ...

launch vehicle and the capsule returns to Earth via

splashdown Splashdown is the method of landing a spacecraft by parachute in a body of water. It was used by crewed American space capsules prior to the Space Shuttle program, by SpaceX Dragon and Dragon 2 capsules and by NASA's Orion Multipurpose ...

in the ocean near Florida. The program's first operational mission,

SpaceX Crew-1 SpaceX Crew-1 (was also known as USCV-1 or simply Crew-1) was the first operational crewed flight of a Crew Dragon spacecraft, and the maiden flight of the Crew Dragon ''Resilience'' spacecraft. It was also the second crewed orbital flight l ...

, launched on 16 November 2020.

Boeing Starliner The Boeing CST-100 Starliner
is a class of two partially final test flight, launched atop an

Atlas V N22 Atlas V is an expendable launch system and the fifth major version in the Atlas launch vehicle family. It was originally designed by Lockheed Martin, now being operated by United Launch Alliance (ULA), a joint venture between Lockheed Martin ...

launch vehicle. Instead of a splashdown, a Starliner capsule will return on land with

airbag An airbag is a vehicle occupant-restraint system using a bag designed to inflate extremely quickly, then quickly deflate during a Traffic collision, collision. It consists of the airbag cushion, a flexible fabric bag, an inflation module, and a ...

s at one of four designated sites in the western United States.

Development of the Commercial Crew Program Development of the Commercial Crew Program began in the second round of the Commercial Crew Development (CCDev) program, which was rescoped from a technology development program for human spaceflight to a competitive development program that woul ...

began in 2011 as NASA shifted from internal development of crewed vehicles to perform ISS crew rotation to commercial industry development of transport to the ISS. A series of open competitions over the following two years saw successful bids from Boeing,

Blue Origin Blue Origin, LLC is an American privately funded aerospace manufacturer and sub-orbital spaceflight services company headquartered in Kent, Washington. Founded in 2000 by Jeff Bezos, the founder and executive chairman of Amazon, the company is ...

,

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...

, and SpaceX to develop proposals for ISS crew transport vehicles. In 2014, NASA awarded separate fixed-price contracts to Boeing and SpaceX to develop their respective systems and to fly astronauts to the ISS. Each contract required four successful demonstrations to achieve human rating for the system: pad abort, uncrewed orbital test, launch abort, and crewed orbital test. Operational missions were initially planned to begin in 2017, with missions alternating between the two providers. Delays required NASA to purchase additional seats on Soyuz spacecraft up to

Soyuz MS-17 Soyuz MS-17 was a Soyuz spaceflight that was launched on 14 October 2020. It transported three crew members of the Expedition 63/ 64 crew to the International Space Station. Soyuz MS-17 was the 145th crewed flight of a Soyuz spacecraft. The ...

until Crew Dragon missions commenced in 2020. Crew Dragon continues to handle all missions until Starliner becomes operational .

Background

In 2004, the Aldridge Commission – established by

President President most commonly refers to: *President (corporate title) * President (education), a leader of a college or university *President (government title) President may also refer to: Automobiles * Nissan President, a 1966–2010 Japanese f ...

George W. Bush George Walker Bush (born July 6, 1946) is an American politician who served as the 43rd president of the United States from 2001 to 2009. A member of the Republican Party, Bush family, and son of the 41st president George H. W. Bush, he ...

following the Space Shuttle ''Columbia'' disaster – called for crewed flights to the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width ...

with a

Crew Exploration Vehicle The Crew Exploration Vehicle (CEV) was a component of the U.S. NASA Vision for Space Exploration plan. A competition was held to design a spacecraft that could carry humans to the destinations envisioned by the plan. The winning design was the ...

in its final report. Following the

NASA Authorization Act of 2005 The NASA Authorization Act of 2005 is an act of the United States Congress that requires NASA to carry out a balanced set of programs in human spaceflight, in aeronautics research and development and in scientific research. It was signed by the ...

, the

Constellation program The Constellation program (abbreviated CxP) was a crewed 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" an ...

was established, which envisioned a revised Crew Exploration Vehicle named Orion conducting crew rotation flights to the

International Space Station The International Space Station (ISS) is the largest Modular design, modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos ( ...

(ISS) in addition to its lunar exploration goals. Orion superseded the

Orbital Space Plane 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 transport. It was part of the Space Lau ...

, which was specifically designed for ISS crew rotation. In 2009, the Augustine Commission appointed by President

Barack Obama Barack Hussein Obama II ( ; born August 4, 1961) is an American politician who served as the 44th president of the United States from 2009 to 2017. A member of the Democratic Party (United States), Democratic Party, Obama was the first Af ...

found that the program's funding and resources were insufficient to execute its goals without significant delays to its schedule and an increase of US$3 billion in funding, which prompted NASA to start considering alternatives to the program. The Constellation program was officially cancelled in 2010, with NASA repurposing Orion for exploration beyond Earth, and collaborating with commercial partners for ISS crew rotation and other crewed activities in

low Earth orbit A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never m ...

following the retirement of the

Space Shuttle program The Space Shuttle program was the fourth human spaceflight program carried out by the U.S. National Aeronautics and Space Administration (NASA), which accomplished routine transportation for Earth-to-orbit crew and cargo from 1981 to 2011. I ...

in 2011. This arrangement would additionally end NASA's dependency on

Roscosmos The State Space Corporation "Roscosmos" (russian: Государственная корпорация по космической деятельности «Роскосмос»), commonly known simply as Roscosmos (russian: Роскосмос) ...

'

Soyuz program The Soyuz programme ( , ; russian: link=no, Союз , meaning "Union") is a human spaceflight programme initiated by the Soviet Union in the early 1960s. The Soyuz spacecraft was originally part of a Moon landing project intended to put a ...

to deliver its astronauts to the ISS.

Development

CCDev awards

The

NASA Authorization Act of 2010 The NASA Authorization Act of 2010 is a U.S. law authorizing NASA appropriations for fiscal years 2011, 2012, 2013 with the same top-line budget values as requested by US President Barack Obama. It resulted from the Augustine Commission's review o ...

allocated US$1.3 billion for an expansion of the existing Commercial Crew Development (CCDev) program over three years. While the program's first round of competition in 2010 focused on funding development of various human spaceflight technologies in the private sector as part of the

American Recovery and Reinvestment Act American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

, its second round, CCDev 2, focused on proposals for spacecraft capable of shuttling astronauts to and from the ISS. The competition for CCDev 2 funding concluded in April 2011, with

Blue Origin Blue Origin, LLC is an American privately funded aerospace manufacturer and sub-orbital spaceflight services company headquartered in Kent, Washington. Founded in 2000 by Jeff Bezos, the founder and executive chairman of Amazon, the company is ...

receiving US$22 million to develop its biconic nose cone capsule concept,

SpaceX Space Exploration Technologies Corp. (SpaceX) is an American spacecraft manufacturer, launcher, and a satellite communications corporation headquartered in Hawthorne, California. It was founded in 2002 by Elon Musk with the stated goal of ...

receiving US$75 million to develop a crewed version of their Dragon spacecraft and a human-rated Falcon 9 launch vehicle, the

Sierra Nevada Corporation Sierra Nevada Corporation (SNC) is an American, privately held aerospace and national security contractor specializing in aircraft modification and integration, space components and systems, and related technology products for cybersecurity and ...

receiving US$80 million to develop the

Dream Chaser Dream Chaser is an American reusable lifting-body spaceplane being developed by Sierra Nevada Corporation (SNC) Space Systems. Originally intended as a crewed vehicle, the Dream Chaser Space System is set to be produced after the cargo var ...

, and

Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and ...

receiving US$92.3 million to develop the

CST-100 Starliner The Boeing CST-100 Starliner
is a class of two partially SpaceX had previously been contracted by NASA to operate ISS resupply flights with their Dragon spacecraft, as part of NASA's

Commercial Resupply Services Commercial Resupply Services (CRS) are a series of flights awarded by NASA for the delivery of cargo and supplies to the International Space Station (ISS) on commercially operated spacecraft. The first CRS contracts were signed in 2008 and awarde ...

. The program's third round, Commercial Crew integrated Capability (CCiCap), aimed to financially support the development of winning proposals over 21 months through to May 2014, in preparation for crewed missions to the ISS within five years. Despite winning awards in CCDev 1 and CCDev 2, Blue Origin decided against competing in CCiCap, opting instead to rely on private investment from their owner,

Jeff Bezos Jeffrey Preston Bezos ( ;; and Robinson (2010), p. 7. ''né'' Jorgensen; born January 12, 1964) is an American entrepreneur, media proprietor, investor, and commercial astronaut. He is the founder, executive chairman, and former preside ...

, to continue development on crewed spaceflight. The competition for CCiCap funding ended in August 2012, with US$212.5 million allocated to Sierra Nevada's Dream Chaser, US$440 million allocated to SpaceX's Crew Dragon, and US$460 million allocated to Boeing's Starliner. While

Alliant Techsystems Alliant Techsystems Inc. (ATK) was an American aerospace, defense, and sporting goods company with its headquarters in Arlington County, Virginia, in the United States. The company operated in 22 states, Puerto Rico, and other countries. AT ...

's integrated

Liberty Liberty is the ability to do as one pleases, or a right or immunity enjoyed by prescription or by grant (i.e. privilege). It is a synonym for the word freedom. In modern politics, liberty is understood as the state of being free within society fr ...

launch vehicle and spacecraft was a finalist, it was rejected due to concerns about the lack of detail in Alliant Techsystems's proposal. In December 2012, the three CCiCap winners were each given an additional USD$10 million in funding as the first of two series of "certification products contracts" (CPC) to allow for further testing, engineering standards, and design analysis to meet NASA's safety requirements for crewed spaceflight. The second CPC series manifested as Commercial Crew Transportation Capability (CCtCap), the final phase of the CCDev program, where NASA would certify an operator to run crewed flights to the ISS through an open competition. The window for proposal submissions was closed on 22 January 2014. Sierra Nevada announced a week later that a privately-funded orbital test flight of a Dream Chaser spacecraft, using an

Atlas V Atlas V is an expendable launch system and the fifth major version in the Atlas launch vehicle family. It was originally designed by Lockheed Martin, now being operated by United Launch Alliance (ULA), a joint venture between Lockheed Marti ...

launch vehicle intended to be purchased by Sierra Nevada, was planned to occur on 1 November 2016. On 16 September 2014, CCtCap concluded with SpaceX's Crew Dragon and Boeing's Starliner being the sole winners, with SpaceX receiving US$2.6 billion contract and Boeing a US$4.2 billion contract. Sierra Nevada filed a protest with the Government Accountability Office (GAO) in response, citing "serious questions and inconsistencies in the source selection process." The

United States Court of Federal Claims The United States Court of Federal Claims (in case citations, Fed. Cl. or C.F.C.) is a United States federal court that hears monetary claims against the U.S. government. It was established by statute in 1982 as the United States Claims Court, ...

upheld a decision to allow development of the Crew Dragon and Starliner to proceed during the protest, citing concerns for crewed operations of the ISS in the event of a delay to the Commercial Crew Program. The GAO declined Sierra Nevada's protest in January 2015, stating that evidence gathered by the GAO discredited Sierra Nevada's claims against NASA; Sierra Nevada accepted the decision. The company laid off 90 staff members working on the Dream Chaser following the CCtCap result, and repurposed the spacecraft as a for-hire vehicle for commercial spaceflight. A cargo variant of the Dream Chaser would later be developed and selected by NASA to fly uncrewed resupply missions to the ISS under a

Commercial Resupply Services 2 Commercial Resupply Services (CRS) are a series of flights awarded by NASA for the delivery of cargo and supplies to the International Space Station (ISS) on commercially operated spacecraft. The first CRS contracts were signed in 2008 and awarde ...

contract.

Post-selection

While the first flights of Commercial Crew Program were originally intended to be launched by the end of 2017, Boeing announced in May 2016 that their first crewed flight would be delayed to 2018 due to issues related to Starliner's Atlas V N22 launch vehicle. In December 2016, SpaceX announced their first crewed flights would also be delayed to 2018, following the loss of

AMOS-6 AMOS-6 was an Israeli communications satellite, one of the Spacecom AMOS series, that was built by Israel Aerospace Industries (IAI), a defense and aerospace company. AMOS-6 was intended to be launched on flight 29 of a SpaceX Falcon 9 t ...

in an accidental launch pad explosion of a

Falcon 9 Falcon 9 is a partially reusable medium lift launch vehicle that can carry cargo and crew into Earth orbit, produced by American aerospace company SpaceX. The rocket has two stages. The first (booster) stage carries the second stage and pa ...

, the Crew Dragon's launch vehicle. With no further flights in the

Soyuz program The Soyuz programme ( , ; russian: link=no, Союз , meaning "Union") is a human spaceflight programme initiated by the Soviet Union in the early 1960s. The Soyuz spacecraft was originally part of a Moon landing project intended to put a ...

for American astronauts past 2018, the GAO expressed concerns and recommended in February 2017 that NASA develop a plan for crew rotation in the event of further delays. Following the settlement of a lawsuit against Russian space manufacturer

Energia Energia or Energiya may refer to: * Energia (corporation), or S. P. Korolev Rocket and Space Corporation Energia, a Russian design bureau and manufacturer ** Energia (rocket), a Soviet rocket designed by the company *Energia (company), a company th ...

over

Sea Launch Sea Launch was a multinational—Norway, Russia, Ukraine, United States—spacecraft launch company founded in 1995 that provided orbital launch services from 1999–2014. The company used a mobile maritime launch platform for equatorial lau ...

, Boeing received options for up to five seats on Soyuz flights, which NASA purchased from Boeing. NASA announced the astronauts chosen to pilot the Crew Dragon and Starliner vehicles in August 2018, and two months later penned the launch of demonstration missions for the Crew Dragon and Starliner for dates in 2019. The uncrewed SpaceX Demo-1 mission was launched on 2 March 2019, in which a Crew Dragon successfully docked with the ISS and returned to Earth six days after launch. The capsule used in the mission, however, was accidentally destroyed in a static fire test of its

SuperDraco SuperDraco is a hypergolic propellant rocket engine designed and built by SpaceX. It is part of the SpaceX Draco family of rocket engines. A redundant array of eight SuperDraco engines provides fault-tolerant propulsion for use as a launch escap ...

engines in April 2019, causing further delays to launch of future Crew Dragon flights. The

Boeing Orbital Flight Test The Boeing Starliner Orbital Flight Test (also known as Boe-OFT) was the first orbital mission of the CST-100 Starliner spacecraft, conducted by Boeing as part of NASA's Commercial Crew Program. The mission was planned to be an eight-day test ...

and Boeing Crew Flight Test, which had both been delayed due to a failed test of Starliner's abort system, were further pushed without explanation from dates in early-to-mid 2019 to late 2019. Boeing conducted the

Boeing Pad Abort Test The Boeing Pad Abort Test (also abbreviated to Boe-PAT) was a test of the Boeing CST-100 Starliner The Boeing CST-100 Starliner NASA accepted the test as successful even though one of three parachutes failed to deploy, since the system landed as designed under two parachutes. Boeing conducted the Orbital Flight Test in December 2019 and encountered major malfunctions of Starliner's software which precluded an intended docking with the ISS and prompted a truncation of the mission. The Orbital Flight Test was declared a "high-visibility close call" by NASA following an independent review, and a second Orbital Flight Test (Boeing OFT-2) was scheduled for July 2021, with Boeing covering the cost of the flight in lieu of additional CCDev funding. Amid further uncertainties about the Commercial Crew Program's progress, NASA purchased a seat on the

Soyuz MS-17 Soyuz MS-17 was a Soyuz spaceflight that was launched on 14 October 2020. It transported three crew members of the Expedition 63/ 64 crew to the International Space Station. Soyuz MS-17 was the 145th crewed flight of a Soyuz spacecraft. The ...

mission to ensure participation in

Expedition 64 Expedition 64 was the 64th long-duration expedition to the International Space Station (ISS), that began on 21 October 2020 with the undocking and departure of Soyuz MS-16. The Expedition started with the three crew members launched onboard Soy ...

in the event that operational missions in the program are further delayed, with the purchase of additional Soyuz seats beyond MS-17 being described as a possibility. The SpaceX In-Flight Abort Test was successfully conducted in January 2020, setting the stage for the final, crewed test flight of Crew Dragon –

SpaceX Demo-2 Crew Dragon Demo-2 (officially Crew Demo-2, SpaceX Demo-2, or Demonstration Mission-2) was the first crewed test flight of the SpaceX Dragon 2, Crew Dragon spacecraft. The spacecraft, named ''Crew Dragon Endeavour, Endeavour'', launched on 30 M ...

– which launched astronauts

Bob Behnken Robert Louis Behnken (; born July 28, 1970, in St. Ann, Missouri) is a NASA astronaut, engineer, and former Chief of the Astronaut Office. Behnken holds a Ph.D in mechanical engineering and the rank of colonel in the U.S. Air Force, where he ...

and

Doug Hurley Douglas Gerald Hurley (born October 21, 1966) is an American engineer, former United States Marine Corps, Marine Corps pilot and former NASA astronaut. He piloted Space Shuttle missions STS-127 (July 2009) and STS-135 (July 2011), the final fligh ...

to the ISS in May 2020. SpaceX launched its first operational flight,

SpaceX Crew-1 SpaceX Crew-1 (was also known as USCV-1 or simply Crew-1) was the first operational crewed flight of a Crew Dragon spacecraft, and the maiden flight of the Crew Dragon ''Resilience'' spacecraft. It was also the second crewed orbital flight l ...

, on 16 November 2020. It stayed docked to the ISS as planned until 2 May 2021.

SpaceX Crew-2 SpaceX Crew-2 was the second operational flight of a Crew Dragon spacecraft, and the third overall crewed orbital flight of the Commercial Crew Program. The mission was launched on 23 April 2021 at 09:49:02 UTC, and docked to the Internationa ...

launched on 23 April 2021 and is landed on 9 November 2021, two days before the launch of

SpaceX Crew-3 SpaceX Crew-3 was the fourth operational flight of a Crew Dragon spacecraft, and the third overall crewed orbital flight of the Commercial Crew Program. The mission successfully launched on 11 November 2021 at 02:03:31 UTC to the International ...

. When Boeing OFT-2 was on the pad preparing for launch on 3 August 2021, problems were encountered with 13 valves in the capsule's propulsion system. The launch was scrubbed and the capsule eventually returned to the factory. Analysis of the problem was still underway in September 2021 and launch was postponed indefinitely. This uncrewed test,

Boeing Orbital Flight Test 2 The Boeing Orbital Flight Test-2 (also known as Boe OFT-2) was a repeat of Boeing's unsuccessful first Orbital Flight Test (OFT-1) of its Starliner spacecraft. The uncrewed mission was part of NASA's Commercial Crew Program. OFT-2, using Star ...

, launched on 19 May 2022, and landed successfully on 25 May. Both commercial Crew vehicles Crew Dragon and Starliner docked to ports on harmony module at the same time

Both commercial Crew vehicles Crew Dragon and Starliner docked to ports on harmony module at the same time

On February 28, 2022, NASA announced that it had awarded three additional crew missions to SpaceX bringing the total crew missions for SpaceX to nine and the total contract value to $3,490,872,904. In September 2022, NASA announced yet another addition, this time of five missions, bringing the total to fourteen and the total contract value to $4.93 billion.

Spacecraft

The Commercial Crew Program uses the

SpaceX Crew Dragon Dragon 2 is a class of partially reusable spacecraft developed and manufactured by American aerospace manufacturer SpaceX, primarily for flights to the International Space Station (ISS). SpaceX has also launched private missions such as Insp ...

to shuttle astronauts to and from the ISS. The

Boeing CST-100 Starliner The Boeing CST-100 Starliner
is a class of two partially touch screen A touchscreen or touch screen is the assembly of both an input ('touch panel') and output ('display') device. The touch panel is normally layered on the top of an electronic visual display of an information processing system. The display is ofte ...

s in case of an emergency. The crew cabins of both spacecraft feature of pressurized volume, and can be configured to carry up to seven crew each, though NASA will only send up to four crew on each mission in the program; an extension to occupy a fifth seat is available to NASA. Both spacecraft can last up to 210 days in space docked to the ISS. In addition, the spacecraft were designed to meet NASA's safety standard of a 1-in-270 chance of

catastrophic failure A catastrophic failure is a sudden and total failure from which recovery is impossible. Catastrophic failures often lead to cascading systems failure. The term is most commonly used for structural failures, but has often been extended to many othe ...

, which is less risky than the 1-in-90 chance of the Space Shuttle. The spacecraft and the ISS have docking mechanisms that implement the

International Docking System Standard The International Docking System Standard (IDSS) is an international standard for spacecraft docking adapters. It was created by the International Space Station Multilateral Coordination Board, on behalf of the International Space Station partne ...

(IDSS). The

NASA Docking System The NASA Docking System (NDS) is a spacecraft docking and berthing mechanism used on the International Space Station (ISS), the Orion spacecraft, and the Starliner. The NDS is NASA's implementation of the International Docking System Standard (I ...

implementation is used by Starliner and ISS, while Crew Dragon uses a compatible IDSS implementation developed by SpaceX. The IDSS docks are used instead of the

Common Berthing Mechanism The Common Mechanism (CBM) connects habitable elements in the US Orbital Segment (USOS) of the International Space Station (ISS). The CBM has two distinct sides that, once mated, form a cylindrical vestibule between modules. The vestibule is ...

used by previous

Commercial Orbital Transportation Services Commercial Orbital Transportation Services (COTS) was a NASA program to coordinate the development of vehicles for the delivery of crew and cargo to the International Space Station by private companies. The program was announced on January 18, 200 ...

spacecraft such as the first-generation Dragon. Commercial Crew Program vehicles

Crew Dragon

SpaceX's Crew Dragon is a variant of the company's

Dragon 2 Dragon 2 is a class of partially reusable spacecraft developed and manufactured by American aerospace manufacturer SpaceX, primarily for flights to the International Space Station (ISS). SpaceX has also launched private missions such as Insp ...

class of spacecraft, which is an upgraded version of the first-generation Dragon. It measures wide, tall without its trunk, and with its trunk. While trunks are discarded prior to capsule reentry, crew cabins are designed to be reusable. Alternatively, Crew Dragon spacecraft can be repurposed as uncrewed Cargo Dragon spacecraft for use in SpaceX's

Commercial Resupply Services 2 Commercial Resupply Services (CRS) are a series of flights awarded by NASA for the delivery of cargo and supplies to the International Space Station (ISS) on commercially operated spacecraft. The first CRS contracts were signed in 2008 and awarde ...

missions, with each capsule capable of being flown up to five times. Crew Dragon spacecraft can spend up to a week in free flight without being docked to the ISS. Each Crew Dragon capsule is equipped with a

launch escape system A launch escape system (LES) or launch abort system (LAS) is a crew-safety system connected to a space capsule that can be used to quickly separate the capsule from its launch vehicle in case of an emergency requiring the abort of the launch, suc ...

consisting of eight of SpaceX's

SuperDraco SuperDraco is a hypergolic propellant rocket engine designed and built by SpaceX. It is part of the SpaceX Draco family of rocket engines. A redundant array of eight SuperDraco engines provides fault-tolerant propulsion for use as a launch escap ...

engines, which provide of thrust each. These engines were originally intended to also perform a

propulsive landing Landing is the last part of a flight, where a flying animal, aircraft, or spacecraft returns to the ground. When the flying object returns to water, the process is called alighting, although it is commonly called "landing", "touchdown" or ...

upon return to Earth, with the first test vehicle having been equipped for such capabilities, but these plans were ultimately abandoned in favor of a traditional

splashdown Splashdown is the method of landing a spacecraft by parachute in a body of water. It was used by crewed American space capsules prior to the Space Shuttle program, by SpaceX Dragon and Dragon 2 capsules and by NASA's Orion Multipurpose ...

return near Florida in either the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth#Surface, Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Afr ...

or the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United S ...

. SpaceX's CCtCap contract values each seat on a Crew Dragon flight to be between US$60–67 million on the first six missions, while the face value of each seat has been estimated by NASA's

Office of Inspector General In the United States, Office of Inspector General (OIG) is a generic term for the oversight division of a federal or state agency aimed at preventing inefficient or unlawful operations within their parent agency. Such offices are attached to ma ...

(OIG) to be around US$55 million. Per-mission cost for the first contract extension (missions 7, 8, and 9) is $258.7 million ($64.6 million/seat), and per-mission cost for the second contract extension (missions 10 through 14) is $288 million ($72 million/seat).

Starliner

Boeing's CST-100 Starliner – "CST" an acronym for "Crew Space Transportation" – measures in diameter and in height. The crew module of Starliner can be reused for up to ten flights, while the service module is expended during each flight. Various engines manufactured by

Aerojet Rocketdyne Aerojet Rocketdyne is an American manufacturer of rocket, hypersonic, and electric propulsive systems for space, defense, civil and commercial applications. Headquartered in Sacramento, California, the company is owned by Aerojet Rocketdyne Hold ...

for

orbital maneuver In spaceflight, an orbital maneuver (otherwise known as a burn) is the use of propulsion systems to change the orbit of a spacecraft. For spacecraft far from Earth (for example those in orbits around the Sun) an orbital maneuver is called ...

ing,

attitude control Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle ...

, reaction control, and launch escape, are utilized by Starliner. Eight reaction control engines on the spacecraft's crew module and 28 reaction control engines on the spacecraft's service module provide and each, respectively. Also located on the service module, 20 custom-made Orbital Maneuvering and Attitude Control (OMAC) engines provide of thrust each, while four

RS-88 The RS-88 is a liquid-fueled rocket engine burning ethanol as fuel, and using liquid oxygen (LOX) as the oxidizer. It was designed and built by Rocketdyne, originally for the NASA Bantam System Technology program (1997). In 2003, it was designa ...

engines provide of thrust each in a launch abort scenario. During a nominal flight without a launch abort, Starliner can use unspent fuel reserved for its RS-88 engines to help its OMAC engines perform the orbital insertion burn, following separation from the Centaur upper stage during launch. Once in space, Starliner spacecraft can survive up to 60 hours in free flight. Unlike Crew Dragon, Starliner is designed to return to Earth on land instead of ocean, using

airbag An airbag is a vehicle occupant-restraint system using a bag designed to inflate extremely quickly, then quickly deflate during a Traffic collision, collision. It consists of the airbag cushion, a flexible fabric bag, an inflation module, and a ...

s to cushion the vehicle's impact with the ground. Four sites in the western

contiguous United States The contiguous United States (officially the conterminous United States) consists of the 48 adjoining U.S. states and the Federal District of the United States of America. The term excludes the only two non-contiguous states, Alaska and Hawai ...

– the

Dugway Proving Ground Dugway Proving Ground (DPG) is a U.S. Army facility established in 1942 to test biological and chemical weapons, located about southwest of Salt Lake City, Utah, United States, and south of the Utah Test and Training Range. Location Dugway ...

in

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...

,

Edwards Air Force Base Edwards Air Force Base (AFB) is a United States Air Force installation in California. Most of the base sits in Kern County, but its eastern end is in San Bernardino County and a southern arm is in Los Angeles County. The hub of the base is E ...

in

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the ...

,

White Sands Missile Range White Sands Missile Range (WSMR) is a United States Army military testing area and firing range located in the US state of New Mexico. The range was originally established as the White Sands Proving Ground on 9July 1945. White Sands National P ...

in

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe, New Mexico, Santa Fe , LargestCity = Albuquerque, New Mexico, Albuquerque , LargestMetro = Albuquerque metropolitan area, Tiguex , Offi ...

, and

Willcox Playa The Willcox Playa is a large endorheic dry lake or sink (playa) adjacent to Willcox, Arizona in Cochise County, in the southeast corner of the state. It is part of the Sonoran Desert ecoregion and is the remnant of a Pleistocene era pluvial La ...

in

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a U.S. state, state in the Southwestern United States. It is the list of U.S. states and territories by area, 6th largest and the list of U.S. states and territories by population, 14 ...

– will serve as landing ranges for returning Starliner spacecraft, though in an emergency scenario, it is also equipped to perform a splashdown return. Boeing's CCtCap contract values each seat on a CST-100 flight to be between US$91–99 million, while the face value of each seat has been estimated by NASA's OIG to be around US$90 million.

Missions

NASA missions to the ISS launch on an average every six months. As part of the original contracts Boeing and SpaceX each were initially contracted for up to six operational flights. NASA later contracted with SpaceX for up to an additional eight flights as a contingency if Starliner is further delayed and to ensure service to the ISS until 2030.

Crew Dragon Missions

SpaceX's

Crew-1 SpaceX Crew-1 (was also known as USCV-1 or simply Crew-1) was the first operational crewed flight of a Crew Dragon spacecraft, and the maiden flight of the Crew Dragon ''Resilience'' spacecraft. It was also the second crewed orbital flight ...

mission, the first operational flight in the program, carried Victor Glover, Mike Hopkins,

Soichi Noguchi is a Japanese aeronautical engineer and former JAXA astronaut. His first spaceflight was as a Mission Specialist aboard STS-114 on 26 July 2005 for NASA's first "return to flight" Space Shuttle mission after the ''Columbia'' disaster. He was ...

, and

Shannon Walker Shannon Walker (born June 4, 1965) is an American physicist and a NASA astronaut selected in 2004. She launched on her first mission into space on June 25, 2010, onboard Soyuz TMA-19 and spent over 163 days in space. She returned to space for ...

to the ISS in November 2020 aboard ''

Resilience Resilience, resilient, resiliency, or ''variation'', may refer to: Science Ecology * Ecological resilience, the capacity of an ecosystem to recover from perturbations ** Climate resilience, the ability of systems to recover from climate change * ...

''. ''Resilience'' was originally planned to be used for

Crew-2 SpaceX Crew-2 was the second operational flight of a Crew Dragon spacecraft, and the third overall crewed orbital flight of the Commercial Crew Program. The mission was launched on 23 April 2021 at 09:49:02 UTC, and docked to the Internati ...

, but was reassigned following a scheduling change resulting from the accidental destruction of C204 during testing. While NASA astronauts were given assignments to either Crew Dragon or Starliner flights, Noguchi – a

JAXA The is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology development and launch of satellites into o ...

astronaut – was open for assignment to whichever spacecraft would launch the first operational mission. With

Chris Cassidy Christopher John "Chris" Cassidy (born January 4, 1970) is a retired NASA astronaut and United States Navy SEAL. Chris Cassidy achieved the rank of captain in the U.S. Navy. His first spaceflight was on a Space Shuttle mission in 2009. He was th ...

having arrived at the ISS during

Soyuz MS-16 Soyuz MS-16 was a Soyuz spaceflight launched on 9 April 2020, which transported three members of the Expedition 62/ 63 crew to the International Space Station. This flight was the first crewed launch using the Soyuz 2.1a launch vehicle, and ...

, the arrival of the astronauts aboard ''Resilience'' marked the first time since the Space Shuttle program in which the

US Orbital Segment The US Orbital Segment (USOS) is the name given to the components of the International Space Station (ISS) constructed and operated by the United States National Aeronautics and Space Administration (NASA), European Space Agency (ESA), Canadia ...

of the ISS was completely staffed with four crew. Crew-2 launched in April 2021, using a previously-flown Falcon 9 first-stage booster and a refurbished Crew Dragon for the first time. The mission carried

Shane Kimbrough Robert Shane Kimbrough (born June 4, 1967) is a retired United States Army officer and NASA astronaut. He was part of the first group of candidates selected for NASA astronaut training following the Space Shuttle ''Columbia'' disaster. Kimbrou ...

,

Megan McArthur Katherine Megan McArthur (born August 30, 1971) is an American oceanographer, engineer, and NASA astronaut. She has served as a Capsule Communicator (CAPCOM) for both the Space Shuttle and International Space Station (ISS). Megan McArthur has ...

,

Akihiko Hoshide is a Japanese engineer, JAXA astronaut, and former Commander of the International Space Station. On August 30, 2012, Hoshide became the third Japanese astronaut to walk in space. Early life and education He was born in 1968 in Tokyo, Japan. H ...

and

Thomas Pesquet Thomas Gautier Pesquet (; born 27 February 1978 in Rouen) is a French aerospace engineer, pilot, and European Space Agency astronaut. Pesquet was selected by ESA as a candidate in May 2009, and he successfully completed his basic training in Nove ...

aboard ''

Endeavour Endeavour or endeavor may refer to: People Fictional characters * Endeavour Morse, central character of the ''Inspector Morse'' novels by Colin Dexter * Endeavor, the hero name for the character Enji Todoroki from the anime series ''My Hero A ...

''. Crew-3 launched in November 2021, carrying

Thomas Marshburn Thomas Henry Marshburn (born August 29, 1960) is an American physician and a NASA astronaut. He is a veteran of three spaceflights to the International Space Station and holds the record for the oldest person to perform a spacewalk at 61 years ol ...

,

Raja Chari Raja Jon Vurputoor Chari (born June 24, 1977) is an American test pilot and NASA astronaut. He is a graduate of the United States Air Force Academy, Massachusetts Institute of Technology, and U.S. Naval Test Pilot School, and has over 2,000 flyi ...

,

Matthias Maurer Matthias Josef Maurer (born 18 March 1970) is a German European Space Agency astronaut and Materials scientist, who was selected in 2015 to take part in space training. Biography Maurer graduated from in Sankt Wendel, Saarland, in 1989.) He t ...

and

Kayla Barron Kayla Jane Barron (born September 19, 1987) is an American submarine warfare officer, engineer and NASA astronaut. Barron was selected in June 2017 as a member of the NASA Astronaut Group 22, and later qualified as an astronaut in 2020. Barr ...

to the ISS, and Crew-4 launched

Kjell Lindgren Kjell Norwood Lindgren (born January 23, 1973) is an American astronaut who was selected in June 2009 as a member of the NASA Astronaut Group 20. He launched to the International Space Station (ISS) as part of Expedition 44/ 45 on July 22, 20 ...

, Bob Hines,

Samantha Cristoforetti Samantha Cristoforetti, OMRI (; born in Milan on 26 April 1977) is an Italian European Space Agency astronaut, former Italian Air Force pilot and engineer. She holds the record for the longest uninterrupted spaceflight by a European astronaut (1 ...

and

Jessica Watkins Jessica Andrea Watkins (born May 14, 1988) is an American NASA astronaut, geologist, aquanaut and former international rugby player. Watkins was announced as the first Black woman who will complete an International Space Station long-term mis ...

in April 2022. US astronauts

Josh Cassada Josh Aaron Cassada (born July 18, 1973) is an American physicist, test pilot, and NASA astronaut. Prior to his selection to join NASA in 2013, Cassada served as a test pilot in the US Navy, and has over 3,500 hours in more than 40 aircraft, and 2 ...

,

Nicole Aunapu Mann Nicole "Duke" Victoria Aunapu Mann (born June 27, 1977) is an American test pilot and NASA astronaut. She is an F/A-18 Hornet pilot, and a graduate of the US Naval Academy, Stanford University and the US Naval Test Pilot School. She has over 2, ...

and JAXA astronaut

Koichi Wakata is a Japanese engineer and a JAXA astronaut. Wakata is a veteran of four NASA Space Shuttle missions, a Russian Soyuz mission, and a long-duration stay on the International Space Station. During a nearly two-decade career in spaceflight, he has ...

initially assigned to Starliner crewed flights were re-assigned to Crew-5 mission after delays in the Starliner program. The fourth astronaut on Crew-5 is filled by a Russian cosmonaut

Anna Kikina Anna Yuryevna Kikina (russian: Анна Юрьевна Кикина, born 27 August 1984 in Novosibirsk) is a Russian engineer and cosmonaut, selected in 2012. She is the only woman cosmonaut currently in active service at Roscosmos. In June 2 ...

and thus becoming to be a part of the Soyuz-Dragon crew swap system, that is, keeping at least one NASA astronaut and one Roscosmos cosmonaut on each of the crew rotation missions. That would ensure both countries would have a presence on the station, and ability to maintain their separate systems, if either Soyuz or commercial crew vehicles are grounded for an extended period. On 3 December 2021, NASA made clear it would secure up to an additional three flights from SpaceX to maintain an uninterrupted U.S. capability for human access to the space station. The background to this was that SpaceX was likely to launch its sixth flight in early 2023 potentially before Boeing's first operational flight, and NASA concluded that only SpaceX had the capability needed. NASA and

Roscosmos The State Space Corporation "Roscosmos" (russian: Государственная корпорация по космической деятельности «Роскосмос»), commonly known simply as Roscosmos (russian: Роскосмос) ...

have agreed to an annual seat-swapping agreement for three flights each. In 2022, 2023, and 2024, a Russian cosmonaut will fly on one Crew Dragon flight per year while an American astronaut will fly on one

Soyuz Soyuz is a transliteration of the Cyrillic text Союз ( Russian and Ukrainian, 'Union'). It can refer to any union, such as a trade union (''profsoyuz'') or the Union of Soviet Socialist Republics (Сою́з Сове́тских Социали� ...

flight per year. This arrangement ensures that ISS will have at least one crew member to operate essential services even if one or the other type of spacecraft is grounded. On 31 August 2022, NASA awarded SpaceX with an additional 5 flights bringing the total number of contracted Crew Dragon flights to 14. The additional flights will run though 2030.

Boeing Starliner Missions

Boeing's first operational mission in the program,

Starliner-1 Boeing Starliner-1 is planned to be the first operational crew mission of the Boeing Starliner to the International Space Station (ISS) as part of the Commercial Crew Program. It would be the fourth orbital flight mission of the Starliner overa ...

, was planned to ferry astronauts

Sunita Williams Sunita Lyn Williams (born September 19, 1965) is an American astronaut and United States Navy officer who formerly held the records for most spacewalks by a woman (seven) and most spacewalk time for a woman (50 hours, 40 minutes). Williams was ...

and

Jeanette Epps Jeanette Jo Epps (born November 3, 1970) is an American aerospace engineer and NASA astronaut. Epps received both her M. S. and Ph.D degrees in aerospace engineering from the University of Maryland, where she was part of the rotor-craft research ...

to the ISS in 2022 aboard ''

Calypso Calypso refers to: * Calypso (mythology), a nymph who, famously in Homer's ''Odyssey'', kept Odysseus with her on her island of Ogygia for seven years. * Calypso (nymphs), other nymphs called Calypso. Calypso may also refer to: Books * "C ...

''. On 18 April 2022, NASA said that it has not finalized which of the cadre of Starliner astronauts, including

Barry Wilmore Barry Eugene "Butch" Wilmore (born December 29, 1962) is a NASA astronaut and United States Navy test pilot. He has had two spaceflights, the first of which was an 11-day Space Shuttle mission in November 2009, to the International Space Statio ...

,

Michael Fincke Edward Michael "Mike"/"Spanky" Fincke (born March 14, 1967) is an American astronaut who formerly held the American record for the most time in space (381.6 days). His record was broken by Scott Kelly on October 16, 2015. Mike Fincke was bor ...

, and

Sunita Williams Sunita Lyn Williams (born September 19, 1965) is an American astronaut and United States Navy officer who formerly held the records for most spacewalks by a woman (seven) and most spacewalk time for a woman (50 hours, 40 minutes). Williams was ...

, will actually fly on the CFT mission or the first operational Starliner mission. NASA astronaut

Jeanette Epps Jeanette Jo Epps (born November 3, 1970) is an American aerospace engineer and NASA astronaut. Epps received both her M. S. and Ph.D degrees in aerospace engineering from the University of Maryland, where she was part of the rotor-craft research ...

continues to prepare for an upcoming long duration mission aboard Starliner-1. NASA has also identified backup flight opportunities for Epps on the SpaceX Crew Dragon for additional scheduling and resource flexibility. Epps has begun cross-training on the Crew Dragon to prepare for this. NASA hopes to extend the seat-swapping arrangement with Roscosmos to include Starliner flights after Starliner has enough flights.

Operational CCP missions

Timeline

The CCP spacecraft missions usually overlap with brief intervals during which two are docked at the same time. Crew-2 did not overlap with Crew-3 because of an unexpected delay in Crew-3 launch.

References

Sources # # # Citations Notes

External links

Commercial Crew Program
at

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedi ...

(Archive
1 March 2019

CCtCap contract
between

Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and ...

and NASA
CCtCap contract
between

SpaceX Space Exploration Technologies Corp. (SpaceX) is an American spacecraft manufacturer, launcher, and a satellite communications corporation headquartered in Hawthorne, California. It was founded in 2002 by Elon Musk with the stated goal of ...

and NASA {{Crewed ISS flights 2010s in spaceflight 2020s in spaceflight Human spaceflight programs International Space Station NASA programs Projects established in 2011 Private spaceflight

Background

Development

CCDev awards

Post-selection

Spacecraft

Crew Dragon

Starliner

Missions

Crew Dragon Missions

Boeing Starliner Missions

Operational CCP missions

Timeline

See also

References

External links