NASA and Boeing Chart Phased Roadmap to Bring Starliner Back to Service

Key facts

• NASA and Boeing outlined a phased roadmap to return the Starliner spacecraft to service after technical issues during the crewed test flight that carried Sunita Williams and Butch Wilmore to the International Space Station.
• An uncrewed Starliner-1 mission is scheduled to launch in December or January 2027 to validate spacecraft improvements and gather flight data.
• NASA plans to return astronauts on Starliner-2 by 2028 and intends to exercise options for a fifth and sixth Starliner flight to the International Space Station.
• NASA will certify the United Launch Alliance Vulcan rocket for human spaceflight after the final Atlas V retirement flight.
• A post-flight inquiry produced 61 recommendations, and investigators found the service-module reaction-control thrusters operated outside engineering qualifications, causing control anomalies linked to thermal factors and system design.
• Boeing has integrated thermal adjustments into the service module, redesigned a thruster valve to fix poppet-seal extrusion issues, and added new crew-module thrusters, updated batteries, and parachute revisions.
• Dana Weigel, manager of NASA's Low Earth Orbit Programme, described Starliner-1 as a critical engineering evaluation flight for reviewing updated thermal dynamics and clearing residual risks before crewed flight.