Teams NASA And Boeing’s gave the green light for the unmanned spacecraft to leave the International Space Station at 18:04 on September 6, leaving the astronauts behind. NASA Butch Wilmore and Suni Williams board the Starliner from Cape Canaveral on June 5.

The duo reached the ISS a day later, but due to engine problems and a helium leak in the Starliner thrust module, NASA decided to take a risk and leave the astronauts at the station to wait for a rescue flight home from Boeing’s rival SpaceX.

If the weather is clear at the landing site, Starliner It has docked autonomously with the ISS, and could do so as early as 2022, on the second of two uncrewed test flights. It will then face a six-hour flight back to Earth, with the aim of landing in the desert at White Sands Space Center in New Mexico at 12:03 a.m. on September 7. After landing by parachute and flying vehicle, it will be returned to the Boeing Starliner factory at Kennedy Space Center.

At this point, Wilmore and Williams will officially become part of the Expedition 71/72 crew on station.

While the SpaceX Crew-9 mission with Crew Dragon Freedom is set to launch as early as Sept. 24 to replace the current SpaceX Crew-8 crew on the ISS, Williams and Willmore won’t return home until the Freedom mission concludes on the ISS in February — meaning they will spend eight to nine months on board once they return.

But they will be only the second and third people to fly in four spacecraft, joining Orlando native John Young, who flew in Gemini, Apollo, the Apollo Lunar Module and the Space Shuttle. Both Wilmore and Williams have flown in the space shuttle, the Russian Soyuz and the Starliner. Their flight in the SpaceX Dragon will be their fourth.

NASA plans to send only two of the four crew members on the upcoming SpaceX mission to make room for Williams and Wilmore, but it has not yet been announced whether two of the three NASA astronauts and a Russian cosmonaut will remain on board.

But since the ISS only has two parking spaces for ships from the likes of Boeing and SpaceX, the Starliner needs to get underway before it arrives.

Both companies were initially awarded contracts under NASA’s Commercial Crew program to bring back American launches to transport astronauts to and from the ISS after the Space Shuttle program ended and ended reliance on Russian Soyuz launches.

While SpaceX conducted its first human test flight in May 2020, Boeing’s Starliner faced a series of delays that resulted in Wilmore and Williams’ Crew Test Flight mission not getting off the ground until four years later. Boeing now faces a decision on whether to continue with the troubled program, having spent more than $1.6 billion and failed to cash in on most of the $4.2 billion fixed-price contract that is expected to consist of six operational crewed flights to the ISS.

It’s unclear whether NASA would consider making Starliner available for this first mission, Starliner-1, without first relaunching a version of Starliner that could fix the engine and leak issues, especially since the original contract called for the CFT to include a flight to take the crew to the ISS, but not to bring them back.

SpaceX, meanwhile, has flown its four Crew Dragon fleets with 50 people on board 13 times. This includes two people on the first Demo-2 flight and four people on NASA’s eight missions to the ISS, three private commercial flights to the ISS that included former NASA astronauts under the command of Axiom Space, and an orbital mission called Inspiration4 that billionaire Jared Isaacman flew that included the first commercial crew.

Isaacman is looking forward to a return to space this week on the Polaris Dawn flight, which was postponed for the following reasons: first, a helium leak on the launch pad at Kennedy Space Center; then, adverse weather conditions were forecast off the coast of Florida on the landing date; and then, because SpaceX’s Falcon 9 rocket was grounded by the Federal Aviation Administration after one of the Falcon 9’s first-stage boosters failed to land during a Starlink launch.

If SpaceX quickly completes its investigation into the launch vehicle failure and is approved by the FAA, the Polaris Dawn mission could be the next human spaceflight from Florida. If not, Crew-9 could be.

SpaceX also has another commercial mission, called Fram2, that will take four passengers on its first manned polar orbit mission that could fly by the end of the year. Then, in 2025, Crew-10 is scheduled to launch in February, with Axiom Space’s fourth mission scheduled for the spring, with Crew-11 likely to follow by August. The next Starliner flight is confirmed.