Boeing Starliner's first crewed mission delayed over propellant leak, testing

Boeing Starliner’s first crewed mission was delayed again, this time over a propellant leak and the need for additional testing, the company said on Tuesday. 

The aerospace company’s first Starliner mission, carrying two NASA astronauts into space, has now been postponed at least until next week. 

“The teams now are targeting a launch date of no earlier than 4:43 p.m. EDT on Tuesday, May 21, to complete additional testing,” Boeing said in the release. 

The original takeoff date was May 17, but a “small” helium leak pushed the company’s Starline capsule trip to the International Space Station (ISS). 

“Starliner teams are working to resolve a small helium leak detected in the spacecraft’s service module traced to a flange on a single reaction control system thruster,” Boeing said. “Helium is used in spacecraft thruster systems to allow the thrusters to fire and is not combustible or toxic.” 

The delay comes a week after another launch attempt was scrubbed due to a valve problem. Last week's pause was instituted by The United Launch Alliance (ULA) over “an observation on a liquid oxygen self-regulating solenoid relief valve on the Centaur upper stage.” 

Boeing has been developing the Starliner for over a decade in hopes of giving NASA another U.S. spacecraft that can take astronauts to and from the ISS. 

SpaceX’s Crew Dragon capsule first took astronauts in 2020. It was also built under NASA. 

The Atlas 5 rocket, built by ULA, is responsible for launching the Starliner. 

SpaceX has completed at least nine crewed missions while Boeing has completed only two unmanned flights. For development, NASA gave $4 billion to Boeing and $2.6 billion to SpaceX.