NASA: Boeing Starliner flagged
A fresh report has called Boeing’s Starliner issue the 'most serious accident' in its recent program history, renewing scrutiny over the vehicle’s reliability and oversight (x.com). The finding is likely to reshape NASA‑Boeing discussions and could affect crewed flight timelines and contractor risk models going forward (x.com).
NASA formally designated the June 5, 2024 Starliner Crewed Flight Test a Type A mishap and released a Program Investigation Team report dated Feb. 5, 2026 after completing its work in November 2025. (nasa.gov) Investigators found five service‑module reaction control thrusters triggered automatic fail‑offs during ISS rendezvous, with in‑flight troubleshooting restoring four of the five and allowing docking. (nasa.gov) The report identifies the most probable proximate technical drivers as two‑phase oxidizer flow effects (vaporization and cavitation), extrusion of Teflon poppets in oxidizer valves that restricted flow, and high mechanical demand from guidance‑and‑control firing commands. (nasa.gov) Separately, a crew‑module RCS thruster failed during descent—leaving zero fault tolerance for that system—and investigators flagged helium‑manifold leaks and carbazic‑acid corrosion as leading theories for other failures. (nasa.gov) The Program Investigation Team also documented qualification gaps, leadership and decision‑making lapses inside both Boeing and NASA, and NASA Administrator Jared Isaacman said the agency shared responsibility for accepting the vehicle to fly. (nasa.gov) Operational outcomes cited in the report: Starliner returned to Earth uncrewed in September 2024 with the vehicle undergoing ground testing at White Sands, while astronauts Barry “Butch” Wilmore and Sunita “Suni” Williams returned to Earth aboard SpaceX Crew‑9 in March 2025 after an extended stay on the station. (nasa.gov) NASA stated it will not fly another crew on Starliner until the propulsion root causes are understood, the system is fully qualified, and investigation recommendations are implemented. (spaceflightnow.com)
