WASHINGTON — NASA’s inspector general warned in a new report that, because of commercial crew delays, utilization of the International Space Station will drop sharply in 2020 and that NASA runs the risk of losing access entirely by next fall.

The Nov. 14 report by the Office of Inspector General (OIG) concluded that, because of continuing delays by both Boeing and SpaceX, neither company is likely to be certified by NASA for regular flights to the station before the summer of 2020.

Official commercial crew program (CCP) schedules reviewed by the OIG state that SpaceX will have its final certification review for its Crew Dragon spacecraft in January 2020, while that review for Boeing’s CST-100 Starliner is scheduled for February. Those reviews, though, would take place only after the successfully completion of both companies’ crewed test flights, which are unlikely to take place before then.

The reviews also require the closure of hundreds of specific items on each spacecraft, leading the report to conclude that “final vehicle certification for both contractors will likely be delayed at least until summer 2020 based on the number of ISS and CCP certification requirements that remain to be verified and validated.”

The top issues for both companies’ vehicles, the report stated, involved launch abort systems and parachutes. Boeing has completed qualification of its parachutes but still has to complete three of six “reliability tests” for the system. SpaceX has started qualification of the new Mark 3 parachutes for Crew Dragon, including 13 successful tests in a row after two initial failures.

Both companies have experienced problems with parachutes as well. An April 2019 parachute test failure by SpaceX “contributed to at least a 3-month delay in SpaceX’s crewed test flight,” the report stated, while failures of two main parachutes on a cargo Dragon spacecraft in August 2018 required “additional work to improve load balancing on the planned crewed parachute system.” One of three parachutes on Boeing’s Starliner failed to open during the Nov. 4 pad abort test, although the company said days later it identified the cause of the anomaly and inspected other parachutes.

Boeing and SpaceX suffered delays because of problems with launch abort systems on their spacecraft. The Starliner issue, discovered during ground testing in June 2018, led to a one-year delay in the pad abort test. SpaceX performed Nov. 13 a static-fire test of its launch escape thrusters, nearly seven months after a similar test resulted in an explosion that destroyed another Crew Dragon spacecraft.

Those delays will adversely affect NASA’s use of the ISS starting next spring, when the station’s crew drops from six to three, including just one NASA astronaut, Chris Cassidy. That would sharply reduce the ability of NASA and its non-Russian partners to carry out work on what’s formally known as the U.S. On-Orbit Segment, or USOS, part of the station.

“Any reduction in the number of crew aboard the USOS would limit astronaut tasks primarily to operations and maintenance, leaving little time for scientific research,” the OIG report concluded. With three USOS astronauts, the report stated, each can carry out an average of 11.67 hours of research per week per person. A single astronaut, though, would have time for only 5.5 hours of research a week. “Such a reduction may hinder NASA’s ability to address astronaut health risks and develop capabilities needed for deep space exploration missions.”

Moreover, NASA has yet to secure any Soyuz seats after the end of Cassidy’s mission in October 2020. Ken Bowersox, NASA’s acting associate administrator for human exploration and operations, confirmed in a response to the report included in the final document that NASA Administrator Jim Bridenstine formally requested two additional seats, one on a Soyuz in the fall of 2020 and the second on a Soyuz in the spring of 2021, in an Oct. 24 letter to the Russian state space corporation Roscosmos, which has yet to act on the request.

Other steps to mitigate commercial crew delays include plans to extend Boeing’s crewed flight test to a long-duration ISS mission. Bowersox confirmed in the letter that the agency is also considering extending SpaceX’s crewed test flight, Demo-2.

The OIG report highlighted another issue for buying any additional Soyuz seats: that NASA’s waiver to sanctions against Russia under the Iran, North Korea and Syria Nonproliferation Act, or INKSNA, expires at the end of 2020. The report recommended that waiver be extended and that NASA consider prepaying Soyuz seats in full prior to the waiver’s current expiration at the end of 2020.

Bowersox responded that NASA was seeking an INKSNA waiver extension, but that prepayment of Soyuz seats “was determined not to be in the best interest of the U.S. Government.” The Senate version of a NASA authorization bill, approved by the Senate Commerce Committee Nov. 13, would extend NASA’s INKSNA waiver through the end of 2030.

Bowersox also used the response to criticize what he considered to be an overly negative assessment of the state of the commercial crew program and the ISS. The OIG, he wrote, “has described a worst-case scenario that does not reflect NASA’s consistent efforts during the life of the program to mitigate those risks. The scenario presented in the report assumes that CCP systems will be significantly delayed and that NASA will not take any future action to mitigate the impacts on the ISS of that delay.”

He cited as examples of that previous steps the agency took on five separate occasions to deal with commercial crew delays, steps that won the approval of the Aerospace Safety Advisory Panel at a meeting earlier this year. That includes, he said, ongoing discussions with Roscosmos about acquiring additional Soyuz seats. “While these discussions have not concluded yet, NASA believes that the Agency will be able to support continuous U.S. crew on the ISS and that most if not all of the impacts cited in the OIG report will either be avoided altogether or will only be temporary.”

Vice President Mike Pence, speaking Nov. 14 at NASA’s Ames Research Center, offered his own optimistic assessment of the commercial crew program. “Before spring arrives next year, we’re going to send American astronauts on American rockets from American soil, back into space,” he said. “We’re going to have our own platforms to take us back, and we don’t need to hitch a ride with the Russians any more.”