Helium Leak Forces NASA to Delay Boeing Starliner Launch Again

A United Launch Alliance Atlas V rocket with Boeing’s Starliner spacecraft aboard is seen on the launch pad illuminated by spotlights at Space Launch Complex 41 on Sunday, May 5, 2024. Credit: NASA/Joel Kowsky

NASA, Boeing, and ULA have postponed the Boeing Crew Flight Test until May 25 to address a helium leak in the Starliner spacecraft. The additional time will be used to ensure the system’s performance and safety for the flight carrying astronauts Wilmore and Williams to the International Space Station. Preparations continue, with the crew remaining in quarantine until closer to the launch.

To ensure thorough spacecraft closeout processes and flight rationale are completed, the teams at Boeing and United Launch Alliance (ULA), in collaboration with NASA, have decided to postpone the Boeing Crew Flight Test to provide the additional time needed. The revised schedule targets no earlier than 3:09 p.m. EDT on Saturday, May 25, for the launch that will transport NASA astronauts Butch Wilmore and Suni Williams to the International Space Station (ISS).

Helium Leak Assessment

The additional time allows teams to further assess a small helium leak in the Boeing Starliner spacecraft’s service module traced to a flange on a single reaction control system thruster. Pressure testing performed on May 15 on the spacecraft’s helium system showed the leak in the flange is stable and would not pose a risk at that level during the flight. The testing also indicated the rest of the thruster system is sealed effectively across the entire service module. Boeing teams are working to develop operational procedures to ensure the system retains sufficient performance capability and appropriate redundancy during the flight. As that work proceeds, NASA’s Commercial Crew Program and the International Space Station Program will take the next few days to review the data and procedures to make a final determination before proceeding to flight countdown.

Preparations and Quarantine Protocols

The ULA Atlas V rocket and Boeing’s Starliner remain in the Vertical Integration Facility at Space Launch Complex-41 on Cape Canaveral Space Force Station in Florida. The NASA, Boeing, and ULA teams remain committed to ensuring a safe Starliner flight test.

Wilmore and Williams will remain quarantined in Houston as prelaunch operations progress. They will fly back to NASA’s Kennedy Space Center in Florida closer to the new launch date. The duo is the first to launch aboard Starliner to the space station as part of the agency’s Commercial Crew Program. The astronauts will spend about a week at the orbiting laboratory before returning to Earth and making a parachute and airbag-assisted landing in the southwestern United States.

Certification and Future Missions

Upon successful completion of this mission, NASA will begin the final process of certifying Starliner and its systems for regular crewed rotation missions to the International Space Station.