Starliner and Crew Dragon
NASA released new schedules Aug. 2 for test flights by Boeing's CST-100 Starliner (left) and SpaceX's Crew Dragon. Credit: Boeing/SpaceX

Updated 9 a.m. Eastern Aug. 3.

WASHINGTON — NASA released an updated schedule of commercial crew test flights Aug. 2 that confirms Boeing’s revised plans as well as delays for SpaceX’s two demonstration missions.

The agency released the revised schedule with little fanfare ahead of a planned Aug. 3 announcement at the Johnson Space Center of the astronauts that will fly the two companies’ crewed demonstration missions, as well as on the first post-certification, or operational, missions by each company.

Under the new schedule, SpaceX will fly an uncrewed demonstration mission in November 2018, three months later than the previous schedule released by NASA early this year. The crewed demonstration flight, with two astronauts on board, will follow in April 2019, four months later than previously announced.

The revised schedule also confirmed dates provided by Boeing in a call with selected media Aug. 1. That schedule calls for an uncrewed test flight in late 2018 or early 2019, followed by a crewed test flight in mid-2019.

Boeing said it revised its schedule in part because of a problem during a static-fire test of the abort engines for its CST-100 Starliner vehicle in June, when several valves failed to close properly at the end of a 1.5-second test. The company said it has identified the root cause of that incident and will make both operational and technical changes to ensure the valves close properly in the future.

Boeing has also rearranged its test program, pushing back a pad abort test that was scheduled for this summer, before both the uncrewed and crewed test flights, to spring 2019, after the uncrewed flight. That modification is intended to “optimize the program flow,” said John Mulholland, Boeing vice president and commercial crew program manager, noting that the abort system is not needed for the uncrewed flight test.

SpaceX carried out a pad abort test of its Crew Dragon vehicle in May 2015. The spacecraft that will fly the uncrewed flight test arrived in Florida last month after completing thermal vacuum and acoustics tests at NASA’s Plum Brook Station in Ohio.

The NASA statement did not disclose reasons for either company’s delays. A SpaceX spokesman, responding Aug. 3 to questions about the reasons for the latest delays, referred to a separate NASA statement that included comments from Benji Reed, director of crew mission management at SpaceX.

“Safely and reliably flying commercial crew missions for NASA remains the highest priority for SpaceX,” said Reed. “We look forward to launching Crew Dragon — designed to be one of the safest, most-advanced human spaceflight systems ever built — and returning human-spaceflight capabilities to the United States for the first time since the space shuttle program retired in 2011.”

The revised schedule is not surprising given that the space community had widely expected delays of at least several months by both companies. A July 11 report by the U.S. Government Accountability Office noted that NASA’s internal projections offered a “zero percent chance” the companies would be certified for routine ISS missions in early 2019, as official schedules at the time expected.

NASA estimates have predicted even greater delays than what the agency formally announced Aug. 2. In its report, the GAO said NASA’s projected “average” certification date for Boeing was December 2019, and January 2020 for SpaceX, with the potential for both companies to slip well into 2020.

Additional delays would jeopardize NASA’s ability to access the ISS, as its access to seats on Soyuz flights runs out by early 2020. “If NASA does not develop options for ensuring access to the ISS in the event of further Commercial Crew delays, it will not be able to ensure that the U.S. policy goal and objective for the ISS will be met,” the report argued.

Among the options being considered by NASA is to use the crewed flight test as a crew rotation flight by adding a third astronaut to the mission and extending its stay from two weeks to as long as six months. NASA and Boeing announced earlier this year they were studying it, but Mulholland said Aug. 1 no decision would be made about using the test flight in that fashion until next year.

“The mission profile will be determined by NASA,” he said of the crewed test flight. “The decision on the mission timeline will be determined by NASA most probably some time in 2019.”

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...