Boeing Starliner launches for the first time carrying NASA astronauts to the ISS

Boeing launched its first Starliner flight with astronauts on Wednesday, beginning a crucial final flight test of the long-delayed spacecraft.

The launch took off at 10:52 a.m. ET from Cape Canaveral, Florida, with two NASA astronauts aboard. Starliner is carried by a United Launch Alliance Atlas V rocket and is bound for the International Space Station.

About 15 minutes after launch, the rocket released the Starliner capsule in orbit as planned, with the flight going as expected, according to mission control.

NASA's broadcast of the launch also noted that although Starliner has cameras onboard to show inside and outside the cabin, Boeing won't be able to relay video back down to the ground until the spacecraft reaches the ISS.

Starliner will fly in space for about 25 hours before a planned docking with the ISS at 12:15 p.m. on Thursday. The astronauts will then spend about a week on the ISS, focused on testing Starliner, before returning to Earth.

Boeing's crew flight test aims to certify the Starliner system as capable of carrying NASA astronauts to and from the ISS.

Wednesday's liftoff comes after a series of attempts to launch the mission. On Saturday, a launch attempt was called off in the final minutes of the countdown due to a problem with one of the computers that provides ground support to the rocket. In early May, another attempt was called off due to an issue detected with the rocket itself.

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United Launch Alliance — or ULA, a joint venture of Boeing and Lockheed Martin — replaced the rocket's problematic valve after the May attempt and replaced a faulty part in the ground infrastructure computer after Saturday's attempt.

Between the two