Boeing's Starliner Nears ISS Amid Technical Hurdles

Boeing's Starliner capsule, with astronauts Butch Wilmore and Suni Williams, approaches the ISS, facing delays due to thruster issues. The mission, a key test flight for NASA, aims to demonstrate the spacecraft's capabilities amidst competition with SpaceX. The crew is set to stay on the ISS for eight days before returning.

Boeing's new Starliner capsule and its inaugural two-member NASA crew neared final approach to the International Space Station 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, roughly 200 meters (220 yards) away from the space station, missed an initial time window for docking with the orbital laboratory as mission managers in Houston investigated the failure of some spacecraft thrusters used for precise maneuvering.

Starliner will conduct some thruster tests before its next attempt to approach the space station in a window that opens at 1:33 p.m. EDT (1733 GMT). 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 had originally been scheduled to autonomously dock with the ISS while both are orbiting some 250 miles (400 km) above Earth at approximately 12:15 p.m. ET (1615 GMT).

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 reentry back through Earth's atmosphere and end with a parachute and airbag-assisted landing in the U.S. Desert Southwest, 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 maneuver 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. YEARS OF TECHNICAL PROBLEMS

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.

NASA and Boeing officials at the time pointed to a faulty seal on one thruster component that was failing to keep the helium inside. Boeing built Starliner under contract with NASA to compete with SpaceX's Crew Dragon capsule, which since 2020 has been the U.S. space agency's only vehicle for sending ISS crew members to orbit from American soil. The current mission marks Starliner's first test flight with astronauts aboard, a requirement before NASA can certify the capsule for routine astronaut missions.

Selected as crew for the pivotal flight were two NASA veterans who have previously logged 500 days in space between them: Wilmore, 61, a retired Navy captain and fighter pilot, and Williams, 58, a former Navy helicopter test pilot with experience flying more than 30 different aircraft. Getting Starliner to this point has been a fraught process for Boeing under its $4.2 billion, fixed-priced contract with NASA, which wants the redundancy of two different U.S. rides to the ISS.

The Starliner is several years behind schedule and more than $1.5 billion over budget. Meanwhile, Boeing's commercial airplane manufacturing operations have been rocked by a series of crises involving its 737 MAX jetliners.