Boeing's Starliner space taxi arrived at the International Space Station on Friday evening, more than two years later than had been expected.

This was the first time that there was no astronauts on the trip, and it was a crucial milestone for Boeing since the same uncrewed spaceship failed to reach the outpost in 2019. The company spent two and a half years fixing a series of technical problems before getting Starliner back to the launchpad.

After spending a few days at the space station, the craft is expected to parachute to a landing site in the western United States.

A successful conclusion to the mission could give NASA enough confidence to put astronauts on board for the next Starliner flight by the end of the year.

Three years after NASA retired the space shuttles, they hired Boeing to take astronauts to and from the I.S.S. The agency had to rely on Russia to transport astronauts. NASA has a second transportation option that can be used in case of an accident, and it prevents further reliance on Russia, which has become politically complicated since it invaded Ukraine earlier this year.

The nose of the Starliner latched onto one of the docking ports at the space station after it launched from Florida. The time is Eastern. The space station's hatch will be opened on Saturday to allow the astronauts to begin unloading cargo.

There were some problems with the launch, orbital approach and docking. After the second stage of the Atlas 5 rocket that carried Starliner to space separated from the first stage, two of the craft's thrusters failed during a firing to put it in a stable position. The other thrusters kicked in to compensate. Boeing said in a statement that the problem would not pose a risk for the rest of the flight after the subsequent firings.

Boeing reported a problem with the cooling of the spacecraft, but said that the temperatures on the spacecraft remained stable. The company said that other key systems, including navigation, power and communications, worked well.

While on the way to the space station, the craft performed a number of maneuvers.

ImageThe Boeing Starliner capsule launching from Cape Canaveral on Thursday.
The Boeing Starliner capsule launching from Cape Canaveral on Thursday.Credit...Steve Nesius/Reuters
The Boeing Starliner capsule launching from Cape Canaveral on Thursday.

During its final approach, which lasted several hours, the spacecraft slowly and carefully moved along a carefully choreographed path. A series of demonstrations of systems designed to prevent an out-of-control vehicle from colliding with the space station were paused several times.

It waited for an hour in front of the space station because of a last-minute problem with the docking system. The docking port was pushed into contact with the problem after the final nudging by the thrusters.

Boeing will have more work to do before NASA approves Starliner for carrying astronauts after a successful return from space. The safety board that oversees NASA expressed concern last week that Boeing did not have enough people working on the program.

David B. West is a member of the safety board.

After a crewed demonstration mission taking two of three NASA astronauts to the space station, Starliner would begin regular operations. NASA thinks that Boeing will fly one crew mission a year.

Boeing will not be able to tap into any non-NASA business like the ones that have been done by SpaceX. Boeing's vehicle is more expensive. NASA is paying $90 million for each Starliner seat, while the Crew Dragon costs $55 million, according to the NASA inspector general.

Boeing doesn't have access to the rockets needed to fly Starliner missions beyond what NASA requires. The Atlas 5 rocket is used to launch the spacecraft. The Atlas 5 is powered by Russian-built engines. Congress decided in 2016 to phase out the RD-180s. Boeing has enough Atlas 5 rockets to fulfill its obligations to NASA, but no more.

Starliner can fly on other rockets. The Vulcan has not been approved for crewed missions.

The company is building a private space station called Orbital Reef with two other companies, Sierra Space and Blue Origin, and Boeing officials think Starliner will find wider use in the future.