Starliner

Starliner, officially known as the CST-100 Starliner, is a crewed spacecraft developed by Boeing for NASA's Commercial Crew Program. It is designed to carry astronauts to low Earth orbit destinations, including the International Space Station, and to support future operations in the U.S. domestic launch and return system. The capsule is intended to accommodate a crew of up to seven passengers or a mix of crew and cargo, and it is designed for automated rendezvous and docking as well as emergency abort capabilities. A key feature is land-based landing using parachutes and airbags for a safe, rapid recovery.

The Starliner architecture comprises a crew capsule intended for reentry and crew life support, plus an integrated service module that provides propulsion, power, and environmental controls in orbit. The vehicle is designed to launch atop U.S. launch vehicles such as the Atlas V and, in later plans, the Vulcan Centaur. It uses the International Docking System Standard for autonomous docking with the ISS, with redundancy in its attitude control and life-support systems to support mission resilience and potential long-duration stays.

Development and testing of Starliner began in the 2010s as part of NASA's Commercial Crew program. Two major uncrewed test flights have been conducted: Orbital Flight Test-1 in 2019 and Orbital Flight Test-2 in 2022, intended to validate launch, orbital operations, rendezvous capabilities, and landing systems. OFT-1 encountered a software issue that prevented full rendezvous with the ISS, leading to a desert landing; OFT-2 tested additional mission aspects and demonstrated successful return to Earth. As of the mid-2020s, Boeing and NASA continued certification work toward potential crewed flights and expanded mission use.

Starliner remains one of NASA’s options for crewed access to the ISS alongside SpaceX’s Crew Dragon.