Over 50 days into a mission originally scheduled to last 10 days, NASA and Boeing officials say they are working to prepare for an agency review this week of flight readiness for Boeing’s Starliner space capsule which exhibited multiple issues on its debut crewed flight to the International Space Station that launched June 5.
Following a test firing of thrusters on the docked Starliner capsule Saturday, and weeks of ground-based testing to identify problems with the small propulsion devices that help the spacecraft navigate and maneuver, mission officials say they are ready to assemble and submit the collected data for review. They expressed optimism that the spaceship would be safe to transport veteran NASA astronauts Suni Williams and Butch Wilmore back to Earth in a long-delayed completion of the mission.
“My job is to provide a safe vehicle for return of the crew,” said Mark Nappi, vice president and program manager of Boeing’s Commercial Crew Program, during a press conference last Thursday. “I’m very confident we have a good vehicle to bring the crew back with. We need to take the next steps to show that information to everybody else.”
Previous reports from NASA detailed that five of 28 maneuvering thrusters failed to perform as expected during Starliner’s docking at the space station on June 6. Engineers also identified five small helium leaks, some of which were detected before the spacecraft launched. Helium is used in the capsule’s thruster firing procedure. The issues have led to a series of delays for Starliner’s return flight.
Ground-based tests at NASA’s White Sands Testing Facility in New Mexico have attempted to recreate the conditions that led to the thruster failures. While four of the failed units have been brought back online and appear to be operating within expected parameters, one of the thrusters has been shut down for the remainder of the mission. Officials say they believe the thruster failures are the result of unexpected levels of heat generation and have identified a number of potential causes that they continue to investigate.
When will Starliner return to Earth?
If the capsule is given a green light following the agency flight readiness review process, Starliner could be set for a return flight in August. If the spacecraft is deemed unsafe to return Williams and Wilmore, NASA Commercial Crew Program manager Steve Stich noted there are backup contingencies in place, thanks to SpaceX’s Dragon Crew Capsule program which has completed almost a dozen missions ferrying astronauts back and forth to the ISS.
“Obviously, the luxury in our program today … is we have two different systems that we are flying,” Stich said at last week’s press conference. “I would rather not go into all of those details until we get to that time, if we ever get to that time, on what we plan to do but the beauty of having Dragon and Starliner, two different space transport systems is we can kind of use those as backups.”
Both Stich and Nappi have previously noted that Starliner has been OK’d for use as an emergency return vehicle, should an unseen event at the space station lead to the need for an evacuation, and that the primary option is for Williams and Wilmore to return on the Boeing capsule. There are currently six spacecraft docked at the ISS, including Starliner, and two of them, the SpaceX Dragon and Russian Soyuz MS-25 crew ship, are capable of carrying astronauts back to Earth in addition to Starliner.
Utah’s Dugway Proving Ground was considered a primary return landing site at the beginning of Starliner’s mission, but it’s not clear whether the west desert location will still be at the top of the list for the capsule’s return. Other possible landing sites include two targets in the vast White Sands Missile Range, New Mexico, and Willcox, Arizona, according to NASA. Edwards Air Force Base in California is available as a contingency landing site.