Boeing’s Starliner has successfully reached and associated with The International Space Station, completing an important step for an important test flight that will determine if it is ready for manned missions. The unmanned spacecraft launched on a United Launch Alliance’s Atlas V rocket from Cape Canaveral and traveled more than 25 hours to reach the orbital laboratory.

Starliner made its first attempt to reach the ISS in December 2019, but failed to achieve its goal due to a software problem that prevented the spacecraft’s pushers from launching. In August last year, Boeing had to cancel its launch plans due to a problem with the spacecraft’s valves, which prevented the company from planning a new launch for almost a year.

Although successful, the Orbital Flight Test-2 was not without its own problems. Like The Washington Post reports that two of its 12 main pushers failed shortly after launch and its temperature control system is down. The docking process was also delayed by more than an hour as the ground team made sure the lighting was perfect and the communications were working as intended. There was also a problem with the spacecraft’s docking mechanism, and it had to retract the system before extending it a second time.

Boeing said Starliner’s main engines had failed due to a drop in pressure in the booster chamber, but it was unclear what caused it. The company’s vice president Mark Napie explained that because the pushers are on the service module, which is ejected during the return flight, Boeing may never understand the exact reason for this. However, NASA and the company plan to study other problems to understand them and prevent them from occurring in the future.

Starliner will remain hooked up with the ISS for the next five days before embarking on his return trip, which will see him in the New Mexico desert. If the spacecraft returns successfully to Earth, then Boeing may be sending astronauts into orbit as early as this fall.

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