Crew-2 Crew Dragon
The Crew Dragon spacecraft Endeavour, with the Crew-2 astronauts on board, seen from the International Space Station shortly after undocking Nov. 8. Credit: NASA

WASHINGTON — NASA is planning to purchase five more Crew Dragon missions to the International Space Station from SpaceX, a move the agency says is needed to ensure long-term access to the station.

In a procurement notice published June 1, NASA announced its intent to issue a sole-source modification of its existing Commercial Crew Transportation Capabilities, or CCtCap, contract with SpaceX to add five missions to the station later this decade.

NASA said in the filing that it needed to add the missions to the contract for several reasons, including delays in the development and certification of Boeing’s CST-100 Starliner crew vehicle, projections of when the additional missions would be needed and “the technical challenges associated with establishing and maintaining” crew transportation systems capable of flying every six months.

The notice added that the additional missions “will ensure redundant and backup capabilities through 2030” for the ISS. The White House announced at the end of last year its intent to extend ISS operations through 2030, an extension supported other station partners except for Russia.

In a blog post published without fanfare by NASA late June 1, agency officials said the additional missions will ensure that they can bring Starliner into service without rushing it. “It’s critical we complete Starliner’s development without undue schedule pressure while working to position both Boeing and SpaceX for sustainable operations in the years ahead,” said Steve Stich, NASA commercial crew program manager.

“Boeing’s Orbital Flight Test-2 went very well and we hope to be able to certify the Starliner system in the near future,” said Phil McAlister, director of commercial space at NASA. “However, we will need additional missions from SpaceX to implement our strategy of having each commercial provider flying alternating missions once per year.”

The original CCtCap awards to Boeing and SpaceX in 2014 provided each company with six operational, or post-certification, missions. Boeing has yet to perform any post-certification missions, as Starliner is still in testing. SpaceX is currently on its fourth post-certification mission, Crew-4, which launched to the station in April.

NASA, anticipating that SpaceX would soon complete all six missions while Starliner was still in development, awarded SpaceX three additional mission in February for $776 million. The new modification, if it goes forward, would bring the total number of post-certification missions awarded to SpaceX to 14.

By the time SpaceX starts flying those additional missions, Boeing’s Starliner should be in service. NASA and Boeing officials said after the completing of the OFT-2 uncrewed test flight May 25 that they believed they would be able to proceed with a crewed test flight as soon as late this year. If that is successful, Starliner could begin post-certification missions as soon as the fall of 2023, after SpaceX’s Crew-6 mission slated to launch in the spring of 2023.

If that schedule holds, and NASA is able to alternate missions between the two companies, Boeing’s current contract would support missions launching through 2028. SpaceX’s extended contract would allow missions to 2030, with SpaceX returning to two missions a year after the conclusion of Boeing’s contract.

NASA said in the statement that the extension planned for SpaceX “does not preclude NASA from seeking additional contract modifications in the future for additional transportation services as needed.” In the case of Boeing, an extension would likely also require certification of a new launch vehicle, as its current Starliner missions are slated to fly on the Atlas 5, a vehicle that United Launch Alliance is no longer offering for sale and plans to retire, likely with the last Starliner mission.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...