Boeing Starliner faces technical issues: How will astronauts Barry Wilmore and Sunita Williams return to Earth?

Boeing's Starliner spacecraft, carrying astronauts Barry Wilmore and Sunita Williams, is gearing up for its return journey from the International Space Station (ISS) despite facing technical challenges since its June 5 liftoff. The capsule has encountered five helium leaks, five maneuvering thruster failures, and a propellant valve issue, requiring extensive troubleshooting by the crew and mission control in Houston.

Delayed ReturnNASA has postponed the return of the astronauts three times, with no set date yet. Starliner can remain docked at the ISS for up to 45 days, potentially extending to 72 days if needed. The latest internal return goal is July 6, significantly prolonging what was initially planned as an eight-day mission.

Technical Hurdles
The primary concern revolves around Starliner's propulsion system, critical for its departure from the ISS and reentry into Earth's atmosphere. Overheating thrusters and helium leaks, likely related to usage frequency, have emerged as major obstacles. Steve Stich, NASA's commercial crew manager, expressed confidence in a safe return following recent test-firings of the thrusters, but further tests and reviews are ongoing.

Mission Management
NASA and Boeing's mission management team is actively analyzing propulsion data, conducting simulations in Houston, and exploring potential solutions, such as software updates or operational adjustments, to address the issues. Despite the challenges, both NASA and Boeing remain committed to ensuring a successful return for the astronauts.

Contingency Planning for Starliner's Return
Despite the ongoing propulsion system issues, NASA has affirmed that Boeing's Starliner spacecraft remains capable of safely returning astronauts Wilmore and Williams to Earth if necessary. This contingency plan would be enacted in the event of an emergency on the ISS or if any critical components on Starliner, such as its solar panels, face unexpected malfunctions.

Crew Dragon Comparison
Unlike the current mission, NASA did not set a scheduled return date for Crew Dragon's first manned mission in 2020. That mission lasted 62 days, longer than planned, due to astronauts assisting with ISS maintenance during a staffing shortage.

Alternative Return Options
If Starliner is unable to safely return the astronauts, one option would be to use Crew Dragon, which has a higher capacity for emergency evacuations. While this scenario is considered unlikely, it would be a significant setback for Boeing. However, NASA and Boeing officials, along with program engineers, have indicated that current issues do not suggest the need for such a contingency.

Historical Precedent
The last instance of a NASA astronaut requiring an alternative ride home was in 2022, when a coolant leak occurred in Russia's Soyuz capsule after delivering two cosmonauts and American astronaut Frank Rubio to the ISS. Although Crew Dragon was considered as a potential alternative, Rubio ultimately returned to Earth in an empty Soyuz capsule launched by Russia as a rescue craft. His mission duration was extended to 371 days, setting a record for the longest duration in space by an American.

(With inputs from Reuters)