Boeing's Starliner capsule crew face issues while attempting to dock with ISS
CBC
Boeing's new Starliner capsule and its inaugural two-member NASA crew neared final approach to the International Space Station (ISS) for docking on Thursday, a key test in proving the vessel's flight-worthiness and sharpening Boeing's competition with Elon Musk's SpaceX.
The spacecraft was proceeding to its planned rendezvous despite an earlier loss of some of its guidance thrusters due to a helium propulsion leak, which NASA and Boeing said should not compromise the mission.
The CST-100 Starliner, with veteran astronauts Barry "Butch" Wilmore and Sunita "Suni" Williams aboard, was due to arrive at the orbiting platform after a flight of roughly 25 hours, following its launch from Cape Canaveral Space Force Station in Florida.
The reusable gumdrop-shaped capsule, dubbed "Calypso" by its crew, was lofted into space on Wednesday atop an Atlas V rocket furnished and flown by Boeing-Lockheed Martin's United Launch Alliance joint venture.
It was scheduled to autonomously dock with the ISS while both are orbiting some 400 kilometres above Earth, at approximately 12:15 p.m. ET.
The spacecraft's approach to the ISS was being livestreamed on a NASA webcast, which showed video images of the capsule captured by a camera aboard the space station.
Once securely coupled to the space laboratory, Wilmore and Williams would conduct a series of standard procedures, such as checking for airlock leaks and pressurizing the passage between the capsule and the ISS, before opening the entry hatches.
They would be welcomed aboard by the outpost's current seven resident crew members: four fellow U.S. astronauts and three Russian cosmonauts.
Plans call for Wilmore and Williams to remain aboard the station for about eight days, then depart on a return flight that will take Starliner on a fiery re-entry back through Earth's atmosphere and end with a parachute- and airbag-assisted landing in the U.S. southwest desert, a first for a crewed NASA mission.
On its voyage to the ISS, helium leaks were detected on Starliner's propulsion system, knocking out some of the 28 thrusters used by the capsule to manoeuvre in space. The astronauts remain safe, and the spacecraft has backup thrusters to compensate for the loss, according to NASA and Boeing.
Starliner uses helium to add pressure to the propellant for its thrusters. NASA and Boeing did not specify the positions of the downed thrusters or how quickly helium was leaking.
NASA mission managers early on Thursday morning gave Boeing the green light to proceed to rendezvous.
The Starliner launch on Wednesday followed years of technical problems, various delays and a first successful 2022 test mission to the orbital laboratory without astronauts aboard.
Last-minute glitches had nixed the Starliner's first two crewed launch attempts, including a helium leak found on the capsule's propulsion system that officials later determined was not serious enough to warrant a mechanical fix.