The development of Starliner has not gone smoothly. During its first in 2019, which didn’t have people on board, it to reach its orbit. The was later traced to an onboard clock was set incorrectly — causing the Starliner’s thrusters to fire at the wrong time.

Starliner never made it to the ISS on that trip, and NASA required a second test flight without any astronauts. When it launched again in 2022, two thrusters on Starliner failed to fire as expected. It successfully switched to backup thrusters and docked to the space station.

Astronauts were supposed to launch last year, but then Boeing found two more problems with the spacecraft: issues with the parachute that allow to float back to Earth, and tape used to wiring that posed a fire risk. Fixing both issues pushed back the launch to this spring.

Finally, Williams and Wilmore were strapped in on May 6, when more problems appeared — a valve on the rocket launching Starliner had to be replaced, and mission engineers discovered the Starliner itself was leaking helium.

Helium gas is used to pressurize Starliner’s propulsion system, and NASA took several weeks to the leaks weren’t enough to the helium to run out during the mission.

星际客机(Starliner)的发展并不顺利。在其2019年的**无人试飞中，未能达到预定轨道。问题后来被追溯到机载时钟设置错误——导致星际客机的推进器在不正确的时间启动。

在那次旅行中，星际客机从未抵达国际空间站(ISS)，美国国家航空航天局(NASA)要求再进行一次无宇航员的试飞。2022年再次发射时，星际客机上的两个推进器未能按预期启动。它成功切换到备用推进器并与空间站对接。

宇航员本应在去年发射升空，但波音公司又在航天器上发现了两个问题：允许宇航员返回地球时漂浮的降落伞系统出现问题，以及用于固定电线的胶带存在潜在的火灾风险。解决这两个问题将发射推迟到了今年春天。

最终，威廉姆斯和威尔莫尔于5月6日绑好安全带准备起飞，但此时又出现了更多问题——发射星际客机的火箭上有一个阀门卡住，必须更换，任务工程师还发现星际客机本身存在氦气泄漏问题。

氦气用于给星际客机的推进系统加压，美国国家航空航天局花了几周时间来确定泄漏并不严重，不会导致任务期间氦气耗尽。