Nasa again defers Boeing's Starliner crewed mission after helium leak

Earlier launch on May 7 was cancelled due to issue with space capsule's oxygen relief valve

The United States’ space agency is deferring Boeing's inaugural crewed flight of its Starliner capsule once again. This delay is to give engineers more time to study a helium leak in the spacecraft's propulsion system.

In a statement, the National Aeronautics and Space Administration (Nasa) said that the launch for May 25 has been put on hold and the date is under discussion.

Nasa said, "The team has been in meetings for two consecutive days, assessing flight rationale, system performance, and redundancy. There is still forward work in these areas…"

The recent delay of Starliner's inaugural mission with crew onboard occurs as mission officials intensify their examination of a helium leak in Starliner's propulsion system. This issue was discovered alongside a problem with the Atlas booster just before the spacecraft was scheduled to launch from Florida on May 7.

The first crewed flight of Boeing's Starliner spaceship was slated to depart from the Kennedy Space Centre in Florida's Cape Canaveral at 8.04 am (IST) on May 7. However, just 90 minutes before the liftoff, the launch of the Atlas V rocket, which is built by United Launch Alliance (ULA), was cancelled due to an issue with an oxygen relief valve.

Astronauts Sunita Williams and Barry Wilmore were scheduled to pilot the Starliner to the International Space Station (ISS).

Inaugural crewed voyage for Starliner

As part of Nasa's Commercial Crew Programme, this mission marks the inaugural crewed voyage for the Starliner spacecraft. It aims to comprehensively evaluate the spacecraft's capabilities, from launch to docking, and conclude with its return to Earth in the western United States. Upon a successful crewed flight test, Nasa will initiate the final stages of certifying Starliner and its systems for future crewed missions to the space station.

Upon launch, Starliner will ascend into orbit propelled by an Atlas V rocket. Following liftoff, the crew will manually pilot the spacecraft to assess its operational capabilities. The capsule, shaped like a gumdrop with a cabin akin in size to an SUV, is scheduled to attach with the ISS for a week-long mission.

During this period, Williams and Wilmore will execute various tests to validate Starliner's functionality before embarking on a parachute-assisted landing in the western US upon return to earth.

Previous delays in Boeing's mission

In 2019, a software malfunction during an initial unmanned test flight led to the capsule missing its intended trajectory and failing to reach the ISS. Nasa said the failure was caused due to insufficient safety checks by Boeing.

In 2021, blocked valves led to the postponement of another launch attempt. Subsequently, in May 2022, the vessel successfully docked with the ISS during an unmanned mission.

However, additional issues, such as subpar parachutes and flammable cabin tape, surfaced, leading to further delays in the crewed test flight crucial for Starliner's certification for regular Nasa missions to the ISS.