NASA has paid Boeing about $2.7 billion of the $4.6 billion total potential value of the commercial crew contract so far, according to Finch. The Starliner contract, which NASA awarded to Boeing in 2014, originally had a maximum value of $4.2 billion, but contract modifications since 2014 have increased that by $400 million. Most of the money NASA has paid Boeing so far has gone toward Starliner development costs, while the remaining funds in the contract cover future payments for services for operational flights.
So if Boeing canceled Starliner, the company would lose nearly $1.9 billion in potential revenue from NASA, which is more than the $1.6 billion it has lost so far on the program.
Ready to go
Since the decision last month to return Starliner without a crew, NASA managers have reviewed plans for the spacecraft to fly away from the space station on autopilot. Preparations included updating Starliner’s software parameters to allow for an autonomous undock. Then, last Thursday, NASA officials convened a flight readiness review and cleared Starliner to return to Earth.
“All respondents answered ‘go’ on this review, depending on the operational status of the vehicle and the weather for landing,” said Steve Stich, NASA’s commercial crew program manager. “So we’re on track for undocking and landing on Friday.”
As Starliner approached the space station on June 6, five of the spacecraft’s 28 Reaction Control System (RCS) engines lost network connectivity, forcing Wilmore to take over manual control while ground controllers tried to recover some of the thrusters.
Engineers tested the engines and analyzed data for more than two months to determine the cause of the engine failures. Ground crews were able to restore operation to four of the five damaged engines, but NASA officials could not be sure that the same engines, or more, would not overheat again and fail as Starliner left the station and headed for atmospheric reentry.
Investigators found that repeated pulses from the RCS engines caused temperatures to rise in the engines. This likely caused a gasket in each of the problem engines to bulge and deform, restricting fuel flow, according to NASA officials.
Stich said Wednesday that possible workarounds for future Starliner flights include changing the way the spacecraft fires its engines to prevent overheating, changing the seal design, and modifying the doghouse-like propulsion nacelles that house the engines in the spacecraft’s service module. The design of those “doghouses” causes them to trap heat like a thermos, exacerbating the thermal problem.
Boeing and NASA also need to address helium leaks that plagued the Starliner test flight. Engineers believe a separate set of degraded seals is causing leaks of helium, which the spacecraft uses to pressurize the propulsion system and feed fuel into the engines. Ground controllers have closed valves to isolate the helium system and plug the leaks while Starliner is docked at the space station. Those isolation valves will open before Starliner leaves the space station, but NASA officials say the spacecraft has more than enough helium for the six-hour flight from dock to landing Friday evening.
Wilmore and Williams originally planned to stay on the space station for about eight days, but will now remain residents of the sophisticated until February, from where they will return home on SpaceX’s Dragon spacecraft.
Dana Weigel, NASA’s ISS program manager, said Wednesday that the Starliner astronauts, both veterans of previous six-month stays on the space station, are fully trained to perform spacewalks, operate the lab’s robotic arm, and perform maintenance and science experiments. They will be fully integrated into the space station’s long-term crew, which typically consists of seven residents. With the extended stay of the Starliner crew, the station’s crew size has grown to nine.
Crew changes forced NASA to remove two astronauts from SpaceX’s next Crew Dragon flight launch to the ISS later this month, leaving two seats empty to accommodate Wilmore and Williams when the Dragon spacecraft returns to Earth early next year. This upcoming SpaceX crew rotation will return the station’s crew size to its usual lineup of seven American astronauts and Russian cosmonauts.
This story originally appeared on Ars Technica.