Helium leak delays Boeing’s historic Starliner mission by at least a week

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The world will have to wait at least another week for the highly anticipated first crewed mission of Boeing’s Starliner spacecraft.

The launch was scheduled for May 17 after a previous delay, but teams discovered a small helium leak in the spacecraft’s service module, according to a Boeing statement. Starliner teams traced the leak to a flange on a unique reaction control system thruster, where helium is used to allow the thrusters to fire.

“Teams are now targeting a launch date of no earlier than 4:43 p.m. EDT on Tuesday, May 21, to conduct additional testing,” the statement said.

The mission, dubbed Crew Flight Test, could be the last major step before NASA considers Boeing’s spacecraft ready for routine operations as part of the federal agency’s Commercial Crew Program.

Boeing and NASA are developing tests and solutions for this leak, the statement said. Boeing plans to bring the propulsion system up to the flight pressurization it would reach just before launch, then allow the helium system to vent naturally.

A review of data from a May 6 launch attempt found no other problems, Boeing said.

NASA astronauts who will participate in the mission for a week-long stay at the International Space Station, Suni Williams and Butch Wilmore, were in quarantine before the flight but returned to Houston on May 10 to spend time with their families during operations due diligence, Boeing said.

Williams and Wilmore will return to NASA’s Kennedy Space Center in Florida in the coming days, according to the release.

This event has been a decade in the making – the culmination of Boeing’s efforts to develop a spacecraft worthy of carrying astronauts to and from the International Space Station as part of NASA’s commercial program.

The launch would mark only the sixth maiden voyage of a crewed spacecraft in U.S. history, NASA Administrator Bill Nelson noted at a news conference earlier this month.

“It started with Mercury, then Gemini, then Apollo, the Space Shuttle, then (SpaceX’s) Dragon – and now Starliner,” he said.

Boeing designed the Starliner to rival SpaceX’s prolific Crew Dragon capsule and would join NASA’s efforts to collaborate with private sector partners, expanding U.S. options for transporting astronauts to the International Space Station.

On board, Williams will also make history as the first woman to join such a mission.

Development delays, test flight problems and other costly setbacks have slowed Starliner’s path to the launch pad. Meanwhile, Boeing’s rival in NASA’s commercial crew program – SpaceX – has become the go-to transportation provider for the space agency’s astronauts.

The launch was scheduled for May 6, with Williams and Wilmore already seated aboard the Starliner capsule when engineers discovered a problem and aborted the launch.

The United Launch Alliance team, which is building the Atlas V rocket, identified a pressure regulating valve on a liquid oxygen tank that needed to be replaced. The valve has since been replaced, but the new problem with the helium leak on the Boeing spacecraft which sits atop the rocket causes additional delay.

If the spacecraft launches next week as planned, it and the astronauts inside will detach from the Atlas V rocket after reaching orbit and begin firing their own engines. The Starliner will likely spend more than 24 hours gradually moving toward the space station.

Williams and Wilmore are expected to spend about a week aboard the orbiting laboratory, joining the seven astronauts and cosmonauts already on board, while the Starliner remains docked outside.

The two men will then return home aboard the same Starliner capsule, which is expected to parachute to a landing in one of several designated locations in the southwestern United States.