due to ongoing issues with the vehicle's propulsion systems astronauts Sunni Williams and Butch Wilmore will remain aboard the International Space Station ISS longer than expected returning home next year via SpaceX capsule instead of Boeing's troubled Starliner spacecraft NASA announced on Saturday that the two astronauts who have been on the ISS for several months as part of a test flight for Boeing Starliner will not return on the vehicle due to safety concerns this decision marks another setback for Boeing a major Aerospace company that has faced multiple challenges in its Aviation and defense sectors this year Bill Nelson NASA's administrator explained during a news conference that a test flight by nature is neither safe nor routine leading to the choice to keep Williams and Wilmore aboard the ISS and bring the Starliner back to Earth without a crew Norman Knight NASA's flight director Chief confirmed that both astronauts fully support the decision and are prepared to continue their mission on the space station this situation adds to the difficulties Boeing has faced in recent years the development of the Starliner has been plagued by various technical issues including software flaws faulty parachutes and propulsion problems Boeing has already incurred significant costs for these setbacks and NASA's decision to opt for spacex's crew Dragon for the astronauts return could further increase expenses for Boeing despite Boeing's belief that the Starliner was safe enough for the return trip NASA officials expressed concerns about the performance of the spacecraft's propulsion system during re-entry particularly after issues were detected with several thrusters during docking Steve stick manager of NASA's commercial crew program highlighted that the thrusters had experienced additional stress and heating raising doubts about their reliability during the critical deorbit burn given these uncertainties NASA decided it was too risky to use the Starline for the astronauts return instead Williams and Wilmore will travel back to Earth on a SpaceX crew Dragon capsule expected to launch in late September their Extended Stay on the ISS will last until February making their mission 8 months long this extension will keep Williams and Wilmore separated from their families for several more months missing holidays and important events back on Earth NASA officials acknowledged the challenges this poses for the astronauts and their families but emphasized that such changes are part of the unpredictable nature of space missions in the meantime the ISS crew will have sufficient supplies thanks to recent and upcoming cargo deliveries NASA's Dana Wile assured that the station's resources have been adjusted to support the additional time Williams and Wilmore will spend in space