Starliner Problems Disrupt Astronaut Return Plans To Earth

Boeing's Starliner capsule, which is still moored on the International Space Station (ISS) (photo: x @Space_Station)

JAKARTA - The problem with Boeing's Starliner capsule, which is still moored on the International Space Station (ISS), has disrupted initial plans to return its two astronauts to Earth. Repairs and last-minute trials prolong a very important mission for the future of the Boeing space division.

NASA has rescheduled the planned return three times, and currently no date has been set. Since its launch on June 5, the capsule has experienced five helium leaks, five dead maneuver boosters, and one propellant valve has failed to completely close. This makes the crew in space and mission managers in Houston spend more time fixing problems during the mission.

The following is an explanation of future potential pathways for Starliner and two NASA veteran astronauts, Barry "Butch" Wilmore and Sunita "Suni" Williams.

Starliner can remain moored on the ISS for up to 45 days, NASA's commercial crew manager Steve Stich commented. However, if necessary, such as if further problems arise that cannot be fixed on time, the capsule can remain moored for up to 72 days, relying on various backup systems.

Internally, NASA scheduled Starliner's latest return on July 6. This date means the mission originally planned for eight days will last for a month. Starliner's disposable propulsion system is part of the capsule's "service module". The problem is currently centered on this system, which is needed to separate the capsule from the ISS and position it to re-enter Earth's atmosphere.

Many Starliners experience excessive heat during use, and helium leaks - which are used to suppress boosters - appear to be linked to how often these boosters are used.

Stich said the latest test drive as Starliner remains moored gave the mission team confidence for a safe return, although trials and reviews are still ongoing. The mission management team, consisting of NASA and Boeing personnel, is researching data on propulsion issues, conducting simulations in Houston, and considering how to fix them, such as updating software or changing how hardware is used.

Once NASA officials give approval for returns, the Starliner booster will be used to remove the capsule from the ISS and begin a journey of about six hours to Earth, gradually tightening its orbit before re-entering Earth's atmosphere to land, assisted by parachutes and airbags, in one of several potential locations in the southwest of the United States.

This is Starliner's first mission into orbit that carries astronauts - the last test NASA needs before NASA can certify it as a second vehicle US space agency to go to the ISS. Starliner will join SpaceX's Crew Dragon, which has dominated the government and private markets for human spaceflight amid Starliner's years of delays.

Despite the propulsion system problem, NASA says Starliners are still able to return astronauts to Earth if needed - for example, if the capsule should serve as a rescue capsule from the ISS in a state of emergency or if the Starliner perishable item - such as the solar panel - shows signs it will expire earlier than planned.

Unlike current missions, NASA did not set a return date for the first Crew Dragon mission to carry astronauts in 2020. The mission eventually lasted 62 days as astronauts needed to help maintain the ISS due to staff shortages.

If Starliner is deemed unable to return Wilmore and Williams to Earth safely, one option is to send them home with Crew Dragon, which brought four astronauts to the station in March and was able to accommodate more people in a state of emergency.

This scenario, which is considered impossible, would be very embarrassing for Boeing. However, NASA and Boeing officials, as well as engineers familiar with the program, say that there is no current problem showing this is necessary.

In this scenario, Starliner's fate will depend on various factors including the extent of its technical problems.

The last time a NASA astronaut needed an alternative vehicle to return home was in 2022, when the Russian Soyuz capsule experienced a cooling leak after sending two cosmonauts and American astronaut Frank Rubio to the station. NASA has considered Crew Dragon as an alternative vehicle for Rubio but eventually he used an empty Soyuz capsule launched by Russia as a rescue ship. Rubio's mission was extended from six months to more than a year - 371 days - a record duration for Americans in space.