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Development of the Commercial Crew Program

Development of the Commercial Crew Program (CCDev) began in the second round of the program, which was rescoped from a smaller technology development program for human spaceflight to a competitive development program that would produce the spacecraft to be used to provide crew transportation services to and from the International Space Station (ISS). To implement the program, NASA awarded a series of competitive fixed-price contracts to private vendors starting in 2011. Operational contracts to fly astronauts were awarded in September 2014 to SpaceX and Boeing, and NASA expected each company to complete development and achieve crew rating in 2017. Each company performed an uncrewed orbital test flight in 2019. SpaceX's Crew Dragon Demo-1 2019 flight of Dragon 2 arrived at the International Space Station in March 2019 and returned via splashdown in the Atlantic Ocean. After completion of its test series, a Crew Dragon spacecraft made its first operational Commercial Crew Program flight, SpaceX Crew-1. The flight launched on November 16, 2020.[1] As of September 2023 SpaceX has completed seven successful CCP flights with another, SpaceX Crew-8, currently in progress. It is contracted with NASA for fourteen operational flights total to the ISS.

The 2019 Boeing Orbital Flight Test of the CST-100 Starliner spacecraft failed to reach the ISS in December 2019. The second test flight, Boeing Orbital Flight Test 2, occurred successfully in May 2022.[2][3][4] Pending completion of its demonstration flights, Boeing is contracted to supply six operational flights to the ISS.[5] The first group of astronauts was announced on August 3, 2018.[6] The first Starliner crewed flight test launched on June 5, 2024.[7] Starliner successfully docked with the station on June 6, 2024, after suffering several helium leaks and thruster malfunctions.[8][9][10] Due to these issues Starliner's return to earth was delayed initially to June 26, 2024, then indefinitely.[11][12] On August 24, 2024 NASA administrator Bill Nelson made the decision to send the Starliner crew back home on SpaceX's Crew Dragon.[13]

Requirements

Key high-level requirements for the Commercial Crew vehicles include:

  • Safely deliver and return four crew members and their equipment to the International Space Station (ISS)[14][15]
  • Provide assured crew return in the event of an emergency[14]
  • Serve as a 24-hour safe haven in the event of an emergency[14][15]
  • Capable of remaining docked to the station for 210 days[14][15]

Background

After the retirement of STS in 2011 and the cancellation of the Constellation program, NASA had no domestic vehicles capable of launching astronauts to space.[16] Artemis, NASA's next major human spaceflight initiative, was scheduled to launch an uncrewed qualification flight in 2016, with an Orion spacecraft atop a Space Launch System (SLS) booster. The NASA had no human-qualified spacecraft available, and in any event SLS/Orion would be too expensive for routine flights to the ISS. In the meantime, NASA continued to send astronauts to the ISS on Soyuz spacecraft seats purchased from Russia.[17] The price varied over time, with the batch of seats from 2016 to 2017 costing $70.7 million per passenger per flight.[18] Artemis continued to slip, with the first uncrewed test flight scheduled for 2022.[19]

Development Program

The CCDev program was initiated to develop safe and reliable commercial ISS crew launch capabilities to replace the Soyuz flights. CCDev followed Commercial Orbital Transportation Services (COTS), an ISS commercial cargo program. CCDev contracts were issued for fixed-price, pay-for-performance milestones.[20] CCDev was implemented in several phases. CCDev 1 contracts were for development of concepts and technologies. CCDev 2 contracts were for actual vehicle designs. CCiCap contracts were for designs of complete end-to-end crew transportation hardware and services. CPC phase 1 contracts were for the development of a full certification plan. Finally CCtCap contracts were awarded for actual demonstration of crewed transportation services, which included development, testing, and production of the required hardware followed by operational flights to the ISS.

CCDev 1

Commercial Crew Development phase 1 (CCDev 1) consisted of $50 million awarded in 2010 to five US companies to develop human spaceflight concepts and technologies.[21][22][23] NASA awarded development funds to five companies under CCDev 1:

  • Blue Origin: $3.7M for a 'pusher' Launch Abort System (LAS) and composite pressure vessels.[24]
  • Boeing: $18M for development of the CST-100 Starliner[25]
  • Paragon Space Development Corporation: $1.4M for a plug-and-play environmental control and life support system (ECLSS) Air Revitalization System (ARS) Engineering Development Unit.[26]
  • Sierra Nevada Corporation: $20M for development of the Dream Chaser[27]
  • United Launch Alliance: $6.7M for an Emergency Detection System (EDS) for human-rating Atlas V[28]

CCDev 2

On April 18, 2011, NASA awarded nearly $270 million to four companies for developing U.S. vehicles that could fly astronauts after the Space Shuttle fleet's retirement.[29] Funded proposals:[30]

Proposals selected without NASA funding:

Proposals not selected:

  • Blue Origin: $22 million. Technologies in support of a biconic nose cone design orbital vehicle, including launch abort system liquid oxygen/liquid hydrogen engines.[31][32]
  • Sierra Nevada Corporation: $80 million. Dream Chaser
  • SpaceX: $75 million. Dragon 2 integrated launch abort system[33]
  • Boeing: $92.3 million. Additional CST-100 Starliner development[34]
  • United Launch Alliance: extend development work on human-rating the Atlas V[35]
  • Alliant Techsystems (ATK) and Astrium proposed development of Liberty.[36] NASA was to share expertise and technology.[37][38]
  • Excalibur Almaz Inc. was developing a crewed system with modernized Soviet-era hardware intended for tourism flights to orbit. An unfunded Space Act Agreement to establish a framework to further develop EAI's spacecraft concept for low Earth orbit crew transportation.[39][40]
  • Orbital Sciences proposed the Prometheus lifting-body spaceplane vehicle[41]
  • Paragon Space Development Corporation proposed additional development of the Commercial Crew Transport-Air Revitalization System.[42]
  • t/Space proposed a reusable eight-person crew or cargo transfer spacecraft[43]
  • United Space Alliance proposed to commercially fly the two remaining Space Shuttle vehicles.[44]

CCiCap

Commercial Crew integrated Capability (CCiCap) was originally called CCDev 3.[45] For this phase of the program, NASA wanted proposals to be complete, end-to-end concepts of operation, including spacecraft, launch vehicles, launch services, ground and mission operations, and recovery. In September 2011, NASA released a draft request for proposals (RFP).[46] The final RFP was released on February 7, 2012, with proposals due on March 23, 2012.[47][48] The funded Space Act Agreements were awarded on August 3, 2012, and amended on August 15, 2013.[49][50]

The selected proposals were announced August 3, 2012:

CPC phase 1

The first phase of the Certification Products Contract (CPC) involved the development of a certification plan with engineering standards, tests, and analyses.[51] Winners of funding of phase 1 of the CPC, announced on December 10, 2012, were:[51]

  • Sierra Nevada Corporation: $10 million
  • SpaceX: $9.6 million
  • Boeing: $9.9 million

CCtCap – crew flights awarded

The Commercial Crew Transportation Capability (CCtCap) is the second phase of the CPC and included the final development, testing and verifications to allow crewed demonstration flights to the ISS.[51] NASA issued the draft CCtCap contract's Request For Proposals (RFP) on July 19, 2013, with a response date of August 15, 2013.[52] On September 16, 2014, NASA announced that Boeing and SpaceX had received contracts to provide crewed launch services to the ISS. Boeing could receive up to US$4.2 billion, while SpaceX could receive up to US$2.6 billion.[53] Dragon was the less expensive proposal, but NASA's William H. Gerstenmaier considered the Boeing Starliner proposal the stronger of the two.[54] In November 2019 NASA published a first cost per seat estimate: US$55 million for SpaceX's Dragon and US$90 million for Boeing's Starliner. Boeing was also granted an additional $287.2 million above the fixed price contract. Seats on Soyuz had an average cost of US$80 million.[55] However, adjusting for the additional cargo carried by Boeing's Starliner inside its crew capsule, the adjusted cost per seat figure is approximately $70 million, which is still higher than SpaceX's Crew Dragon even if the Dragon does not carry the equivalent of a fifth passenger in cargo.[56] Both the CST-100 Starliner and Crew Dragon were to fly an uncrewed flight, then a crewed certification flight, then up to six operational flights to the ISS.[57][58]

Timeline

Ongoing delays

The first flight of the Commercial Crew Program was planned to occur in 2015, but insufficient funding caused delays.[59][60] As the spacecraft entered the testing and production phase, technical issues also caused delays, especially the parachute system, propulsion, and the launch abort system of both capsules.[61]

Starliner 2018 valve issue

In July 2018, a test anomaly was reported in which there was a hypergolic propellant leak due to several faulty abort system valves. Consequentially, the first unpiloted orbital mission was delayed to April 2019, and the first crew launch rescheduled to August 2019.[62][63] In March 2019, Reuters reported these test flights had been delayed by at least three months,[64] and in April 2019 Boeing announced that the unpiloted orbital mission was scheduled for August 2019.[65]

Crew Dragon orbital flight test

The first orbital test of Crew Dragon was an uncrewed mission, commonly called "Demo-1" and launched on March 2, 2019.[66][67] The spacecraft tested the approach and automated docking procedures with the ISS,[68] remained docked until March 8, 2019, then conducted the full re-entry, splashdown and recovery steps to qualify for a crewed mission.[69][70] Life-support systems were monitored for the entirety the test flight.

Crew Dragon explosion

On April 20, 2019, an issue arose during a static fire test of Crew Dragon.[71] The accident destroyed the capsule which was planned to be used for the In-Flight Abort Test (IFAT).[72] SpaceX confirmed that the capsule exploded.[73] NASA stated that the explosion would delay the planned in-flight abort and crewed orbital tests.[74]

Starliner Orbital Flight Test failure

During the first orbital flight test of Starliner in December 2019, the spacecraft reached orbit but was unable to dock with ISS due to a critical software error. Subsequent analysis revealed a second critical software error that could cause the service module to collide with the capsule after separation during the de-orbiting sequence.

Crew Dragon crewed flight

On May 30, 2020, two astronauts were launched to the ISS with a Crew Dragon as part of Crew Dragon Demo-2. The end and safe landing of Demo-2 on August 2, 2020, marked the first splashdown in 45 years for NASA astronauts since the first Apollo–Soyuz U.S./U.S.S.R international space mission in July 1975, as well as the first splashdown of a crew spacecraft in the Gulf of Mexico.

Starliner 2021 valve issue

Shortly before the scheduled launch of the second orbital flight test in August 2021, routine pre-launch testing showed that thirteen valves in the propulsion system were inoperable and the launch was scrubbed. The problem required extensive analysis that was still ongoing in October 2021, and NASA and Boeing estimated that a new launch date would be scheduled in the first half of 2022.

Starliner Orbital Flight Test 2

Boeing Starliner Spacecraft 2 launched as part of the Boeing Orbital Flight Test 2, on May 19, 2022. It successfully docked on May 21, where it stayed for four days.[75] On May 25, the spacecraft undocked and landed successfully in the White Sands Missile Range.[76]

Starliner Crewed Flight Test

Days before a planned launch, Boeing announced in June 2023 that it would delay the Crewed Flight Test indefinitely due to issues with the parachute system and wiring harnesses.[77] The mission entails flying a crew of two NASA astronauts to the International Space Station for a one-week test flight. The Crewed Flight Test successfully launched on June 5, 2024.[7] The Starliner spacecraft docked to the International Space Station the next day after troubleshooting issues with the thrusters on the vehicle.[78] After more thruster testing, both in space and using another Starliner vehicle on Earth, NASA announced on August 24, 2024, that the two astronauts on the mission, Butch Wilmore and Suni Williams, would not return to Earth on Starliner, but instead fly back on Crew Dragon with the SpaceX Crew-9 mission.[79][80] The Starliner spacecraft successfully landed on the September 7, 2024.[81] NASA confirmed on October 15, 2024, that Starliner would not be used for the following two crew rotation missions.[82] In October 2024, Boeing started exploring part of its space business.[83]

Funding

The first flight of the Commercial Crew Program was planned to occur in 2015, but insufficient funding caused delays.[59][60] For the fiscal year (FY) 2011 budget, US$500 million was requested for the CCDev program, but Congress granted only $270 million.[84] For the FY 2012 budget, $850 million was requested and $406 million approved.[85] For the FY 2013 budget, 830 million was requested and $488 million approved.[86] For the FY 2014 budget, $821 million was requested and $696 million approved.[59][87] In FY 2015, $848 million was requested and $805 million, or 95%, was approved.[88] On November 14, 2019, NASA's inspector general published an auditing report listing per-seat prices of $90 million for Starliner and $55 million for Dragon Crew. With these, Boeing's price is higher than what NASA has paid the Russian space corporation, Roscosmos, for Soyuz spacecraft seats to fly US and partner-nation astronauts to the space station. The report also states that NASA agreed to pay an additional $287.2 million above Boeing's fixed prices to mitigate a perceived 18-month gap in ISS flights anticipated in 2019 and to ensure the contractor continued as a second commercial crew provider, without offering similar opportunities to SpaceX.[89] On November 18, 2019, Boeing's Jim Chilton replied that the inspector general's report failed to list Starliner's positive features and objected to the per seat pricing as they believe the cost is lower than $90 million given its cargo capacity. Boeing's reasoning for the extra funding was due to a later start to its development than SpaceX with comparable deadlines. Boeing also stated it committed to the program.[90] The funding of all commercial crew contractors for each phase of the CCP program is as follows—CCtCap values are maxima and include six post-development operational flights for each vendor.

Test Missions

Each system is required to successfully complete abort testing, an uncrewed orbital flight test, and a crewed orbital flight test to meet NASA's requirements for human-rating certification. The agency did allow the companies to propose how they would complete the required tests, with Boeing opting not to perform an in-flight abort test, which NASA approved.[95]

Crew Dragon completed its flight tests in mid-2020 and began operational flights in November 2020. NASA will decide after September 2024 if Boeing has met its certification requirements after the problems experienced on its crew flight test.[96]

Operational missions

Crew Dragon began flying operational missions in November 2020 and had flown eleven missions.

, Starliner is not yet certified and has not flown any operational missions.

See also

  • Commercial Orbital Transportation Services
  • Commercial Resupply Services
  • NASA Docking System
  • Private spaceflight
  • Review of United States Human Space Flight Plans Committee
  • Space Shuttle successors

External links

References

  1. Astronauts fly with SpaceX in landmark launch for commercial spaceflight Spaceflight Now, November 16, 2020, retrieved November 18, 2020^
  2. Jeff Foust. Starliner test flight faces months-long delay SpaceNews, August 13, 2021, retrieved August 13, 2021^
  3. Boeing Starliner test flight planned for spring 2022 SpaceNews, December 20, 2021, retrieved March 27, 2022^
  4. Eric Berger. Leaky valve issue forces Boeing to swap out Starliner's service module Ars Technica, December 14, 2021, retrieved March 27, 2022^
  5. Boeing, SpaceX Secure Additional Crewed Missions Under NASA's Commercial Space Transport Program January 4, 2017^
  6. NASA Assigns Crews to First Test Flights, Missions on Commercial Spacecraft NASA, August 3, 2018^
  7. Ashley Strickland. Boeing spacecraft carrying two astronauts lifts off on historic voyage CNN, June 5, 2024^
  8. NASA Johnson Space Center. The #Starliner crew continues to make their way to the @Space_Station and are in a sleep period. Teams have identified three helium leaks on the spacecraft. One of these was previously discussed before flight along with a management plan. The other two are new since the spacecraft arrived on orbit. Two of the affected helium valves have been closed and the spacecraft remains stable. Follow along for continuous coverage X.com, June 5, 2024, retrieved August 25, 2024^
  9. William Hardwood. A5/Starliner CFT: Four jets apparently were deselected earlier because of suspect readings; two of them operated normally during the hot fire tests and are now considered useable as needed; flight controllers are still assessing the other two; Wilmore and Williams were cleared to press ahead with a manual flying demo before docking, but the commander said his manual operation of the Starliner while the hot fire tests were being conducted was sufficient to meet the goals of the manual demo X.com, June 6, 2024, retrieved August 25, 2024^
  10. Boeing Starliner Spacecraft Completes Successful Crewed Docking with International Space Station investors.boeing.com, retrieved August 25, 2024^
  11. Jeff Foust. NASA's Steve Stich says the Starliner CFT landing has been rescheduled for no earlier than June 26, at White Sands NM at 4:51 am EDT. Was previously scheduled for June 22. X.com, June 18, 2024, retrieved August 25, 2024^
  12. Eric Berger. NASA indefinitely delays return of Starliner to review propulsion data Ars Technica, June 22, 2024, retrieved August 25, 2024^
  13. Eric Berger. It's official: NASA calls on Crew Dragon to rescue the Starliner astronauts Ars Technica, August 24, 2024, retrieved August 25, 2024^
  14. Rob Bayt. Commercial Crew Program: Key Driving Requirements Walkthrough NASA, July 26, 2011, retrieved July 27, 2011^
  15. Commercial Crew Program – fact sheet NASA, February 2012, retrieved July 14, 2012^
  16. Denise Chow. NASA Faces Awkward, Unfortunate Spaceflight Gap Space.com, April 14, 2011, retrieved August 10, 2018^
  17. NASA officials mulling the possibility of purchasing Soyuz seats for 2019 September 29, 2016^
  18. NASA to Pay $70 Million a Seat to Fly Astronauts on Russian Spacecraft Space.com, April 30, 2013^
  19. Gary Daines. First Flight With Crew Will Mark Important Step on Journey to Mars December 1, 2016, retrieved December 23, 2016^
  20. Moving Forward: Commercial Crew Development Building the Next Era in Spaceflight Rendezvous, NASA, 2010, retrieved February 14, 2011^
  21. Selection Statement For Commercial Crew Development JSC-CCDev-1, NASA, December 8, 2009, retrieved February 10, 2011^
  22. NASA Selects Commercial Firms to Begin Development of Crew Transportation Concepts and Technology Demonstrations for Human Spaceflight Using Recovery Act Funds press release, NASA, February 1, 2010, retrieved February 2, 2010^
  23. Commercial Crew and Cargo Program^
  24. Jeff Foust. Blue Origin proposes orbital vehicle^
  25. NASA Selects Boeing for American Recovery and Reinvestment Act Award to Study Crew Capsule-based Design^
  26. CCDev Information NASA, July 20, 2010, retrieved February 1, 2011^
  27. SNC receives largest award of NASA's CCDev Competitive Contract SNC, February 1, 2010^
  28. NASA Selects United Launch Alliance for Commercial Crew Development Program February 2, 2010, retrieved May 19, 2010^
  29. Dean, James. "NASA awards $270 million for commercial crew efforts". space.com, April 18, 2011.^
  30. Frank Jr. Morring. Five Vehicles Vie To Succeed Space Shuttle Aviation Week, April 22, 2011, retrieved February 23, 2011^
  31. , p. 2-1 Space Act Agreement No. NNK11MS02S Between National Aeronautics and Space Administration and Blue Origin, LLC for Commercial Crew Development Round 2 (CCDev 2) retrieved December 5, 2013^
  32. " Blue Origin Technology". Blue Origin. Retrieved February 1, 2016.^
  33. Taking the next step: Commercial Crew Development Round 2 SpaceX Updates webpage, SpaceX, January 17, 2010, retrieved January 17, 2011^
  34. Boeing Submits Proposal for 2nd Round Of Commercial Crew Dev. moonandback.com spaceflight news, December 14, 2010, accessed December 27, 2010.^
  35. NASA Begins Commercial Partnership With United Launch Alliance NASA, retrieved July 18, 2011^
  36. Tariq Malik. Scrapped NASA Rocket May be Resurrected for Commercial Launches SPACE.com, February 8, 2010, retrieved February 10, 2010^
  37. NASA, private firm may team up on Liberty rocket USA Today, retrieved September 13, 2011^
  38. "Commercial Crew Program Forum Presentation", p. 7. commercialcrew.nasa.gov, September 16, 2011.^
  39. CCP and Excalibur Sign Space Act Agreement NASA, retrieved November 18, 2011^
  40. "Excalibur Almaz, NASA sign commercial spaceflight deal"^
  41. The Shape of Things to Come – Orbital's Prometheus™ Space Plane Ready for NASA's Commercial Crew Development Initiative^
  42. (press release) Paragon Space Development Corporation Completes All Development Milestones on the NASA Commercial Crew Development Program Paragon, January 31, 2011^
  43. Alan Boyle. Let's talk about the final frontier Cosmic Log, MSNBC, February 11, 2011, retrieved February 13, 2011^
  44. NASA weighs plan to keep shuttle until 2017 – Technology & science – Space – NBC News NBC News, February 3, 2011^
  45. COMMERCIAL CREW INTEGRATED CAPABILITY NASA, January 23, 2012, retrieved January 25, 2012^
  46. Statement of William H. Gerstenmaier, Associate Administrator for Human Exploration and Operations, National Aeronautics and Space Administration; before the Subcommittee on Space and Aeronautics Committee on Science, Space and Technology; U. S. House of Representatives October 12, 2011, retrieved October 12, 2011^
  47. CCiCap Solicitation NASA, February 7, 2012, retrieved February 11, 2012^
  48. Commercial Crew Integrated Capability Pre-Proposal Conference NASA, February 14, 2012, retrieved February 14, 2012^
  49. NASA Announces Next Steps in Effort to Launch Americans from U.S. Soil NASA, August 3, 2012, retrieved August 3, 2012^
  50. NASA Announces Additional Commercial Crew Development Milestones Space Ref, SpaceRef Interactive Inc., August 15, 2013, retrieved August 16, 2013^
  51. NASA Awards Contracts In Next Step Toward Safely Launching American Astronauts From U.S. Soil NASA, December 10, 2012, retrieved December 11, 2012^
  52. NASA Commercial Crew Transportation Capability Contract CCTCAP Draft RFP SpaceREF, July 19, 2013, retrieved July 22, 2013^
  53. Charlie Bolden. American Companies Selected to Return Astronaut Launches to American Soil NASA.gov, retrieved September 16, 2014^
  54. Why NASA Rejected Sierra Nevada's Commercial Crew Vehicle Aviation Week, retrieved March 3, 2019^
  55. NASA report finds Boeing seat prices are 60% higher than SpaceX November 14, 2019^
  56. Boeing fires back at NASA Inspector General regarding commercial crew report SpaceNews.com, November 19, 2019, retrieved May 25, 2020^
  57. Jeff Foust. NASA Commercial Crew Awards Leave Unanswered Questions Space News, September 19, 2014, retrieved September 21, 2014^
  58. RELEASE 14-256 NASA Chooses American Companies to Transport U.S. Astronauts to International Space Station www.nasa.gov, NASA, retrieved October 29, 2014^
  59. Guy Norris. NASA Chief Repeats Warnings On Commercial Crew Delays Aviation Week, May 31, 2013^
  60. CSF President Michael Lopez-Alegria Statement on NASA Contract Extension with Roscosmos Commercial Spaceflight Federation, May 2, 2013, retrieved May 2, 2013^
  61. NASA's management of crew transportation to the International Space Station NASA Office of Audits, November 14, 2019^
  62. NASA's Commercial Crew Program Target Test Flight Dates October 4, 2018, retrieved October 5, 2018^
  63. Commercial Crew Program – February 6, 2019 blogs.nasa.gov, February 6, 2019, retrieved February 6, 2019^
  64. Eric M. Johnson. Boeing delays by months test flights for U.S. human space program: sources Reuters, March 20, 2019, retrieved March 22, 2019^
  65. Stephen Clark. Boeing delays first Starliner test flight to August, NASA extends duration of first crew mission Spaceflight Now, April 2, 2019, retrieved April 3, 2019^
  66. NASA, Partners Update Commercial Crew Launch Dates NASA Commercial Crew Program Blog, February 6, 2019, retrieved February 6, 2019^
  67. Crew Demo-1 | Launch YouTube, March 2, 2019, retrieved March 8, 2019^
  68. SpaceX Crew Dragon Hatch Open NASA, March 3, 2019, retrieved March 3, 2019^
  69. Crew Demo 1 Mission Overview SpaceX, March 2019, retrieved March 3, 2019^
  70. SpaceX #CrewDragon Demonstration Flight Return to Earth YouTube, March 8, 2019^
  71. Jim Bridenstine. NASA has been notified about the results of the @SpaceX Static Fire Test and the anomaly that occurred during the final test. We will work closely to ensure we safely move forward with our Commercial Crew Program. TWITTER, retrieved April 21, 2019^
  72. Chris Gebhardt. SpaceX and Boeing in home stretch for Commercial Crew readiness NASASpaceFlight.com, August 11, 2017, retrieved August 17, 2017^
  73. Dave Mosher. SpaceX confirmed that its Crew Dragon spaceship for NASA was 'destroyed' by a recent test. Here's what we learned about the explosive failure. Business Insider, retrieved May 6, 2019^
  74. NASA boss says no doubt SpaceX explosion delays flight program June 18, 2019, retrieved June 18, 2019^
  75. The science and cargo of Boeing's OFT-2 Starliner test flight to space station Space.com, May 17, 2022, retrieved May 26, 2022^
  76. NASA. Boeing's Starliner Safely Lands on Earth – Completing Critical Test Flight to Space Station SciTechDaily, May 25, 2022, retrieved May 26, 2022^
  77. Eric Berger. Boeing finds two serious problems with Starliner just weeks before launch Ars Technica, June 1, 2023^
  78. Michael Sheetz. Boeing Starliner docks with ISS, delivering its first NASA crew to space station CNBC, June 6, 2024, retrieved August 26, 2024^
  79. Wes Davis, Andrew Liszewski. NASA will bring the Starliner astronauts home next year on SpaceX's Crew-9 mission The Verge, August 24, 2024, retrieved August 26, 2024^
  80. Michael Sheetz, Michele Luhn. Boeing Starliner returning empty as NASA turns to SpaceX to bring astronauts back from ISS CNBC, August 24, 2024, retrieved August 26, 2024^
  81. Starliner lands safely in New Mexico – Spaceflight Now retrieved 2025-02-02^
  82. Jeff Foust. NASA further delays first operational Starliner flight SpaceNews, 2024-10-17, retrieved 2025-02-02^
  83. Boeing looking to sell space business: report www.foxbusiness.com, retrieved 2025-02-02^
  84. Senate Panel Cuts Commercial Crew, Adds Funds for Orion and Heavy Lift Space News, July 21, 2010, retrieved April 18, 2012^
  85. Stephen Clark. Reduced budget threatens delay in private spaceships Spaceflightnow, November 23, 2011, retrieved April 18, 2012^
  86. Phillip McAlister. Commercial Spaceflight Update NASA, April 18, 2013, retrieved August 10, 2013^
  87. Joe Pappalardo. Is the Relationship Between NASA and Private Space About to Sour? Popular Mechanics, September 16, 2014^
  88. Stephen Clark. NASA gets budget hike in spending bill passed by Congress Spaceflight Now, December 14, 2014, retrieved December 15, 2014^
  89. ERIC BERGER. NASA report finds Boeing seat prices are 60% higher than SpaceX Arstechnica, November 14, 2019, retrieved November 14, 2019^
  90. Doug Messier. Boeing Fires Back at Critical NASA IG Report on Starliner Parabolic Arc, November 18, 2019, retrieved May 13, 2020^
  91. NASA Selects Commercial Firms to Begin Development of Crew Transportation Concepts and Technology Demonstrations for Human Spaceflight Using Recovery Act Funds press release, NASA, February 1, 2010, retrieved June 9, 2012^
  92. NASA Awards Next Set Of Commercial Crew Development Agreements press release, NASA, April 18, 2011, retrieved June 9, 2012^
  93. NASA Releases Commercial Crew Draft RFP, Announces CCDEV2 Optional Milestones press release, NASA, September 19, 2011, retrieved June 9, 2012^
  94. NASA'S MANAGEMENT OF CREW TRANSPORTATION TO THE INTERNATIONAL SPACE STATION Nasa.gov, retrieved June 28, 2020^
  95. Boeing tests crew capsule escape system – Spaceflight Now retrieved August 24, 2024^
  96. NASA Decides to Bring Starliner Spacecraft Back to Earth Without Crew – NASA retrieved August 24, 2024^
  97. Demo-1 Flight Readiness Concludes blogs.nasa.gov, February 22, 2019, retrieved February 22, 2019^
  98. Jeff Foust. Boeing, SpaceX press towards commercial crew test flights this year Spacenews, October 9, 2019, retrieved October 9, 2019^
  99. Jim Bridenstine. Update: #Starliner had a Mission Elapsed Time (MET) anomaly causing the spacecraft to believe that it was in an orbital insertion burn, when it was not. More information at 9am ET:http://nasa.gov/live @JimBridenstine, December 20, 2019, retrieved December 20, 2019^
  100. Launch America – a partnership between NASA and private space companies – will help open the space above Earth to people besides government astronauts. NASA^
  101. Stephen Clark. Live coverage: Atlas 5 rocket sends Starliner toward space station Spaceflight Now, May 19, 2022, retrieved May 20, 2022^
  102. Eric Berger. NASA chief classifies Starliner flight as “Type A” mishap, says agency made mistakes Ars Technica, February 19, 2026, retrieved February 19, 2026^