SLs core stage at Stennis
The core stage of the first SLS being installed on a test stand at the Stennis Space Center earlier this year. Work on the SLS there is suspended as the center moved to Stage 4 of NASA's pandemic response plan. Credit: NASA/SSC

WASHINGTON — A new study found that costs on major NASA projects continued to grow in the last year, and warned some of the agency’s highest profile programs will likely face additional cost overruns and delays in the near future.

The annual assessment of NASA’s major projects by the Government Accountability Office, released April 29, found that, for the third year in a row, the average cost overrun on those projects had increased. Those projects, which include missions and other programs with a total cost of at least $250 million, have suffered an average cost increase of 30.9%, compared to 27.6% in last year’s report and 15.6% in 2017.

The report found slightly better schedule performance for those programs, though, with an average schedule slip of 12 months, down from 13 months in 2019.

The biggest contributor to the cost growth is NASA’s exploration programs, including the Space Launch System, Orion, and their associated ground systems. Of the $1.6 billion in net additional cost growth identified by GAO in the report, $1.3 billion comes from those programs.

The report warned of more overruns to come. “The cost performance of NASA’s portfolio of major projects continues to deteriorate for the third consecutive year and both cost and schedule performance are expected to worsen when NASA announces a new schedule for the Artemis I mission,” the GAO stated.

NASA has yet to announce a new schedule for that mission, which will be the first launch of the SLS. NASA started a review of the schedule for the mission in December, and in late February an agency official suggested the mission would take place in the second half of 2021. That was, though, before the impact of the coronavirus pandemic that has, among other things, halted work on the “Green Run” test of the SLS core stage at the Stennis Space Center since mid-March.

The GAO report, which also does not account for potential delays because of the pandemic, said that NASA was estimating costs based on a March 2021 launch readiness date. “Further delays beyond March 2021 would lead to further cost growth,” it stated.

Of the exploration program increases, more than half, or $700 million, is from SLS, which the GAO said was linked to the delay to March 2021. It also cautioned of risks associated with SLS development during the upcoming Green Run test, notably concerns that the core stage may leak when filled with liquid hydrogen fuel. There is no known leak problem, the report stated, citing program officials, “however, it is difficult to precisely predict how this large volume of liquid hydrogen will affect the stage.”

The GAO warned that there are risks from other Artemis programs needed to achieve a human return to the moon by 2024. The first two modules of the lunar Gateway, the Power and Propulsion Element (PPE) and Habitation and Logistics Outpost (HALO), would qualify as major projects, as well as the Gateway Logistics Services program for cargo transportation and the Human Landing System program for lunar landers. A robotic lunar rover called VIPER and development of lunar spacesuits may also qualify as major projects based depending on their cost, the report noted.

Of those projects, only the PPE is included in the report, since the others are not yet mature enough to have cost and schedule estimates. “The initial effect will be a reduction in cost and schedule growth because new projects are less likely to have experienced cost and schedule growth, but there is a longer-term risk because the programs themselves are risky,” the GAO said of the eventual inclusion of those projects in future reports.

The GAO already warned of potential issues with the PPE based on its use of a solar electric propulsion system being developed separately. The contractor working on that propulsion system “has struggled with its performance, which led NASA to modify the development contract and reduce technical requirements,” the report stated. The PPE could achieve its goals with a lower-power solar electric propulsion system, but would no longer be able to achieve some of the technology demonstration objectives of the program.

Most of the rest of the cost overruns experienced by major NASA projects in the last year involved the Mars 2020 rover mission, which suffered technical problems that drove its cost up by $360 million. NASA officials previously said that those cost overruns required “austerity across the portfolio” of other Mars missions to accommodate it. NASA officials said in mid-April that Mars 2020 remains on schedule for launch during a window that opens July 17 and closes Aug. 5.

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...