Boeing Starliner's Crewed Mission Extended at ISS Amid Technical Reviews

NASA and Boeing have decided to extend the stay of the CST-100 Starliner spacecraft at the International Space Station (ISS) for its inaugural Crew Flight Test (CFT). This decision provides ground teams with additional time to conduct a thorough analysis of the spacecraft's performance, specifically focusing on several small helium leaks and the behavior of its Reaction Control System (RCS) thrusters observed during its flight and docking.

Mission Context and Objectives

The CFT mission, carrying NASA astronauts Butch Wilmore and Suni Williams, is the final major milestone required to certify Boeing's Starliner for regular crew rotation flights to the ISS under NASA's Commercial Crew Program. This program aims to provide reliable and safe transportation for astronauts from American soil, with Starliner poised to become the second such provider alongside SpaceX's Crew Dragon.

Technical Anomalies Under Investigation

During its journey to the space station, flight controllers detected five separate helium leaks in the spacecraft's propulsion system. Additionally, five of the 28 RCS thrusters failed to operate correctly during the final phases of rendezvous and docking. While the teams were able to recover four of the thrusters, the performance anomalies require a comprehensive review.

1. Helium Leaks: The leaks are small and do not pose an immediate threat to the mission. However, engineers are analyzing their root cause and potential impact on future mission phases, particularly the deorbit burn.
2. RCS Thruster Performance: The Reaction Control System is critical for maneuvering. The team is meticulously reviewing flight data to understand the cause of the thruster drop-offs to ensure nominal performance for undocking and reentry.
3. Data-Driven Decisions: Mission managers emphasize that this extended stay is a standard practice in test flights, allowing for an in-depth, data-driven assessment before proceeding with the critical return phase of the mission.

Engineering Analysis and Safety Protocols

Teams at NASA and Boeing are working collaboratively to review all available flight data, conduct system tests while docked, and perform simulations to model the spacecraft's behavior during its return journey. This proactive approach underscores the stringent safety protocols that govern human spaceflight.

We are taking our time and following our standard mission management process. Starliner is performing well in orbit while docked to the space station. We are strategically using the extra time to clear a path for some critical station activities while completing our analysis for a safe return.

Revised Timeline and Next Steps

While an exact new return date has not been finalized, the undocking will be scheduled once the technical reviews are complete and all parties are confident in the spacecraft's readiness. Astronauts Wilmore and Williams will continue to support activities aboard the ISS, contributing to ongoing science experiments and station maintenance.

The extension of Starliner's first crewed mission highlights the rigorous nature of spaceflight certification. Every anomaly provides invaluable data that enhances the safety and reliability of future missions, ultimately strengthening NASA's Commercial Crew Program and humanity's sustained presence in low-Earth orbit.