12:07 pm today

Without astronauts, Boeing's Starliner undocks from space station

12:07 pm today

By Joey Roulette, Reuters

In this screen grab from a NASA livestream, the Boeing Starliner spacecraft can be seen pulling away from the International Space Station for its unmanned return to the surface of Earth on September 6, 2024. Boeing's problem-plagued Starliner is set to finally depart the International Space Station (ISS) on September 6, 2024, returning to Earth without astronauts after NASA deemed the risk too great. (Photo by NASA / AFP) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / NASA" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS

In this screen grab from a NASA livestream, the Boeing Starliner spacecraft can be seen pulling away from the International Space Station for its unmanned return to the surface of Earth. Photo: NASA / AFP

  • Without astronauts, Boeing's Starliner undocks from space station
  • Starliner undocks from ISS for six-hour return trip to Earth
  • Boeing's Starliner faces technical issues, costing $125 million
  • Boeing's future in space questioned amid Starliner struggles

Boeing's Starliner spacecraft undocked from the International Space Station on Saturday (NZ time), leaving behind its first crew of US astronauts to return to Earth empty and finish a drawn-out test mission fraught with technical issues.

NASA astronauts Butch Wilmore and Suni Williams, who became the first two to fly Starliner in June, remained on the ISS with seven other astronauts 400km in orbit as Starliner autonomously departed the laboratory at 6:04pm ET (2204 GMT, 10.04am NZ time) for a six-hour journey toward Earth.

The two astronauts bid farewell to a capsule whose propulsion system problems stretched their eight-day test into an eight-month mission. Stocked with extra food and supplies, Wilmore and Williams will instead return on a SpaceX vehicle in February 2025, NASA announced last week.

Since then, Boeing engineers have uploaded new software to Starliner that allows it to come back without a crew inside. The return trip will be a key test of Starliner's manoeuvring capability.

The capsule is poised to use its manoeuvring thrusters to gradually lower its orbit and reenter Earth's atmosphere at around 11:17pm (0317 GMT / 3.17pm NZ time on Saturday), followed by a parachute-assisted touchdown at the White Sands Space Harbor, an arid military test site in New Mexico.

Five of Starliner's 28 manoeuvring thrusters had failed with Wilmore and Williams on board during their approach to the ISS in June, while the same propulsion system sprang several leaks of helium, which is used to pressurise the thrusters.

Despite successfully docking on 6 June, the failures set off a monthslong investigation by Boeing - with some help from NASA - that has cost the company US$125 million (NZ$202m), bringing total cost overruns on the Starliner program just above $1.6 billion (NZ$2.6b) since 2016, according to a Reuters analysis of securities filings.

Boeing's Starliner woes have persisted since the spacecraft failed a 2019 test trip to the ISS without a crew. Starliner did a re-do mission in 2022 and largely succeeded, though some of its thrusters malfunctioned.

CAPE CANAVERAL, FLORIDA - JUNE 05: NASA’s Boeing Crew Flight Test Commander Butch Wilmore (L) and Pilot Suni Williams walk out of the Operations and Checkout Building on June 05, 2024 in Cape Canaveral, Florida. The astronauts are heading to Boeing’s Starliner spacecraft, which sits atop a United Launch Alliance Atlas V rocket at Space Launch Complex 41 for NASA’s Boeing crew flight test to the International Space Station.   Joe Raedle/Getty Images/AFP (Photo by JOE RAEDLE / GETTY IMAGES NORTH AMERICA / Getty Images via AFP)

Photo: JOE RAEDLE / Getty Images via AFP

The aerospace giant's Starliner woes represent the latest struggle that call into question Boeing's future in space, a domain it had dominated for decades until Elon Musk's SpaceX began offering cheaper launches for satellites and astronauts and reshaped the way NASA works with private companies.

Boeing hopes to recover the Starliner capsule after it touches down in New Mexico and continue its investigation into why the thrusters failed in space.

But the section housing Starliner's thrusters - the "service module" trunk that provides in-space manoeuvring capabilities - is designed to detach from the capsule just before it plunges into Earth's atmosphere.

The service module bearing the faulty thrusters will burn up in the atmosphere, meaning Boeing will rely on simulated tests to figure out what went wrong with the hardware in space.

Starliner, bearing a heatshield to survive its own reentry, will deploy a series of parachutes to slow its descent and inflate a set of exterior airbags moments before touchdown to cushion the impact.

- Reuters

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