NASA
Boeing's Starliner spacecraft, with NASA astronauts Butch Wilmore and Suni Williams aboard, approaches the International Space Station on June 6 as it orbited above the South Pacific Ocean.

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Boeing and NASA announced Friday night that mission officials are again delaying the Boeing Starliner capsule’s return to Earth from the International Space Station.

The announcement is only the latest in a string of recent delays. Officials have pushed back Starliner’s departure date several times after the vehicle — which had launched astronauts Butch Wilmore and Suni Williams to the space station on June 5 — experienced some issues en route to the space station.

Officials did not immediately announce a new return date, but the space agency indicated the return of Starliner’s inaugural crew won’t come until July.

Those issues included five thrusters that abruptly stopped working during flight and a series of helium leaks.

In a blog post, NASA said the move “allow(s) mission teams time to review propulsion system data.”

NASA
iss071e182991 (June 13, 2024) --- The Starliner spacecraft on NASA's Boeing Crew Flight Test is pictured docked to the Harmony module's forward port as the International Space Station orbited 262 miles above Egypt's Mediterranean coast.

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“We are taking our time and following our standard mission management team process,” said Steve Stich, NASA’s Commercial Crew Program manager, in a Friday statement. “We are letting the data drive our decision making relative to managing the small helium system leaks and thruster performance.”

Starliner can spend up to 45 days docked at the orbiting laboratory if needed, Stich said at a prior news conference.

The schedule change also accommodates two upcoming spacewalks that astronauts plan to conduct outside the space station. The latter of those two spacewalks is slated for July 2, indicating Starliner’s return won’t occur before then.

Officials from NASA and Boeing said during a Tuesday news conference, when a previous delay was announced, that they intended to keep the Starliner capsule safely docked with the space station while ground teams attempted to better understand the helium leaks and thruster problems.

At the time, Stich said the vehicle was safe and there was no reason to believe it could not complete the journey home.

“So far, we don’t see any scenario where Starliner is not going to be able to bring Butch and Suni home,” Stich told reporters at the news conference.

Stich reiterated that assessment on Friday, saying in a statement that “Boeing’s Starliner spacecraft remains cleared for return in case of an emergency on the space station that required the crew to leave orbit and come back to Earth.”

“(The astronauts) know that every bit of learning we do on the Crew Flight Test will improve and sharpen our experience for future crews,” Nappi said.

Despite ongoing delays, Mark Nappi, the vice president and program manager of the Commercial Crew Program for Boeing, said in a statement that feedback from Wilmore and Williams about the Starliner spacecraft has been “overwhelmingly positive.”