The troubled Boeing Starliner capsule is back on Earth after a six hour uncrewed flight from the International Space Station that began just after 4 p.m. MDT Friday afternoon when the ship undocked from the station while flying about 260 miles over Central China.
While helium leaks and issues with the spacecraft’s navigational thrusters kept Starliner at the station for three months, extending a mission originally scheduled to last about eight days, no issues were noted by NASA in a livestream of the capsule’s undocking, re-entry and landing procedures.
The capsule’s parachute-assisted descent was captured by night-vision-equipped aircraft and ground-based cameras Friday night as it floated down for a soft landing, aided by nitrogen-filled inflatable airbags, at 10:01 p.m. MDT on the desert floor of the White Sands Missile Range in New Mexico.
The capsule will be shipped back to Florida for post-mission assessments and analysis as Boeing and NASA engineers will continue the work to identify what went wrong with Starliner’s systems. How the issues impact the future of Boeing’s space vehicle program, as well as its contract with NASA, remain unknown.
The path to Starliner’s uncrewed return to Earth
During a prelaunch press conference on Wednesday, NASA officials said they were confident the problem-plagued Boeing Starliner capsule could safely return to Earth in autonomous mode despite the agency’s earlier decision that operational issues with the spacecraft made it “too risky” to carry its two-person crew back from the International Space Station.
In an Aug. 24 announcement, NASA said that ongoing uncertainty and a lack of concurrence among engineers and other experts “does not meet the agency’s safety and performance requirements for human spaceflight, thus prompting NASA leadership to move the astronauts to the (SpaceX Dragon) Crew-9 mission” along with the decision to fly Starliner back uncrewed and using its onboard autonomous piloting systems.
At Wednesday’s press briefing, Steve Stich, manager of NASA’s Commercial Crew Program, noted Starliner has successfully returned from two previous, uncrewed test flights where autonomous systems safely guided the spacecraft back to parachute-assisted ground landings.
“We have confidence in the vehicle, we have confidence that the de-orbit burn will be executed and we have two good landings with Starliner so far,” Stich said. “And expect another one Friday.”
Stich said the agency also completed a required assessment of the vehicle’s condition through the lens of potential threats to public safety on its return voyage and said the consensus was that previous issues with the spacecraft thrusters were not expected to impact Starliner’s flight back to Earth.
Previous reports from NASA and Boeing detailed that five of 28 maneuvering thrusters failed to perform as expected during Starliner’s docking at the International 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. Since then, engineering teams have been scrambling to identify the underlying issues with the thrusters, critical for maneuvering and positioning the spacecraft, including reviewing massive amounts of data, conducting flight and ground testing, hosting independent reviews with agency propulsion experts and developing various return contingency plans, NASA said.
NASA vs. Boeing on Starliner safety status
Stich also noted that the decision to bring Starliner back without its two-person crew, veteran astronauts and Navy test pilots Suni Williams and Butch Wilmore, was not universally supported.
“Boeing believed in the model that they had created to predict thruster degradation for the rest of the flight,” Stich said. “The NASA team looked at the model and saw some limitation. It really had to do with, do we have confidence in the thrusters, and how much we could predict their degradation from undock through the de-orbit burn?”
In an early August press release, Boeing’s commercial space division made a case for the spacecraft’s fitness for bringing its astronauts back safely, providing a lengthy and detailed list of the testing and analysis that had taken place since problems arose on Starliner’s mission that launched June 5 from Cape Canaveral, Florida. Officials from the aerospace giant’s commercial crew program touted their belief in Starliner’s readiness for a safe return but also yielded to NASA’s continued quest, at the time, for better data on the issues.
“Boeing remains confident in the Starliner spacecraft and its ability to return safely with crew,” the release read. “We continue to support NASA’s requests for additional testing, data, analysis and reviews to affirm the spacecraft’s safe undocking and landing capabilities.
“Our confidence is based on this abundance of valuable testing from Boeing and NASA. The testing has confirmed 27 of 28 RCS thrusters are healthy and back to full operational capability. Starliner’s propulsion system also maintains redundancy and the helium levels remain stable.”
Since the decision to send Starliner back empty, NASA has been working with Boeing engineers to update Starliner’s systems for the autonomous return flight. The ship needed to vacate its dock at the International Space Station before late September, when the SpaceX Dragon Crew-9 flight is scheduled to arrive. Williams and Wilmore will remain at the space station until February and are scheduled to accompany two other astronauts back to Earth on the SpaceX Dragon Crew 9 return flight.