Two astronauts wait to come home as Boeing races to understand spacecraft issues. Here’s what’s at stake

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Boeing’s Starliner spacecraft was supposed to achieve a major milestone this month by transporting two NASA astronauts to the International Space Station and proving the capabilities of the capsule, which has faced delays and cost overruns.

The Starliner is now halfway towards achieving this goal. However, the two experienced astronauts on this test flight find themselves in a precarious situation as they have had to extend their stay on the space station for a second time. Engineers on the ground are working tirelessly to investigate the issues that affected the first leg of their journey.

On June 6, Suni Williams and Butch Wilmore, both experienced in spaceflight, arrived at the space station aboard the Starliner. Initially, NASA had estimated that their stay would last approximately one week.
However, the vehicle encountered various issues during its journey, such as helium leaks and malfunctioning thrusters, which have raised concerns about the second half of the mission.

NASA announced on Tuesday that Williams and Wilmore will not return before June 26, extending their mission to at least 20 days. Engineers are working diligently to understand the spacecraft’s problems while it is securely attached to the space station.

While officials have expressed confidence that Starliner will be able to safely bring the astronauts back home, they are eager to thoroughly analyze the remaining data, as stated by Steve Stich, NASA’s Commercial Crew Program manager, during a news conference on Tuesday.
Boeing has chosen to view the mission as a success and an opportunity for learning, despite facing unexpected challenges, according to Mark Nappi, Boeing’s vice president and program manager of the Starliner program. Astronauts extending their stay on the space station is not uncommon, with the Starliner capable of spending up to 45 days there if necessary, as stated by Stich from NASA. However, this situation adds to the list of setbacks experienced by the Boeing Starliner program, which has already been delayed for years. It also contributes to the negative image surrounding Boeing as a company. Overall, it has been a nail-biting ending to the mission.
Boeing and NASA engineers have decided to keep the Starliner spacecraft, along with the astronauts Williams and Wilmore, on the International Space Station for a longer period than initially planned. This decision was made primarily to conduct further analysis due to the helium leaks and thruster issues that occurred on a section of the spacecraft not designed to withstand the journey back to Earth. By delaying the return of the spacecraft, the mission teams hope to gather as much information as possible about the malfunctions in a final attempt to understand what went wrong.

Returning a spacecraft from orbit is always a dangerous endeavor and is considered the most precarious phase of any space mission.

The image shows the Starliner spacecraft, part of NASA’s Boeing Crew Flight Test, docked to the forward port of the Harmony module on June 13, while the International Space Station orbited 262 miles above Egypt’s Mediterranean coast. – NASA
The image shows NASA’s Boeing Crew Flight Test Starliner spacecraft docked to the forward port of the Harmony module on June 13 while the International Space Station was orbiting 262 miles above Egypt’s Mediterranean coast.

During its trip, the Starliner will have to withstand the intense heat generated by Earth’s thick atmosphere as it travels at more than 22 times the speed of sound. The spacecraft’s exterior will reach temperatures of approximately 3,000 degrees Fahrenheit.

Afterward, a set of parachutes, which Boeing recently redesigned and tested in January, will be deployed to safely slow down the capsule before it lands on solid ground. This landing method, unlike the traditional splashdown in the ocean, is a first for a US-made capsule and is expected to simplify the recovery and refurbishment process for the Starliner.

Despite encountering a series of setbacks, the Starliner spacecraft continues to advance towards its mission objectives.
In 2014, NASA selected both Boeing and SpaceX to develop spacecraft capable of transporting astronauts to the International Space Station. At the time, Boeing was considered the more established aerospace company, while SpaceX was viewed as the new and unpredictable player in the industry.

However, over the past decade, the tables have turned. SpaceX’s Crew Dragon spacecraft successfully completed its first crewed mission in 2020, without any major issues. Since then, the vehicle has been regularly used to transport astronauts and paying customers. On May 30, 2020, a SpaceX Falcon 9 rocket launched the Crew Dragon spacecraft with NASA astronauts Robert Behnken and Douglas Hurley, marking its first crewed flight.
Bob Behnken and Doug Hurley, the two astronauts who piloted the inaugural flight of Crew Dragon, ended up staying on the space station for more than 60 days, which was longer than initially planned for a test flight. Their extended stay was not due to any software or hardware issues with SpaceX’s Crew Dragon, but rather because the space station was understaffed and they were able to assist with daily activities.

In contrast, Boeing’s Starliner program has been plagued by spacecraft problems throughout its development. The program has experienced significant delays, setbacks, and additional expenses, totaling over $1 billion according to public financial records.
The initial Starliner test mission, which took place in late 2019 without a crew, experienced numerous setbacks. The spacecraft encountered a malfunction while in orbit, primarily due to software problems. One of the software issues was a coding error that caused the internal clock to be off by 11 hours.

During a second uncrewed flight test in 2022, additional software problems and difficulties with some of the vehicle’s thrusters were discovered. NASA program manager, Stich, stated in a news conference on June 6 that it is possible that the engineers have not completely resolved the issues identified in 2022.

“We believed we had addressed that problem,” Stich remarked, but he also acknowledged that there may be a fundamental issue with the thrusters that they are overlooking.
According to Michael Lembeck, an aerospace engineering associate professor at the University of Illinois Urbana-Champaign and former consultant for Boeing, it would be challenging to determine if additional ground tests could have identified the thruster issues experienced. Lembeck also emphasized that comparing the success of this test mission with the inaugural crewed test flight of SpaceX’s Crew Dragon is not a straightforward task. He pointed out that SpaceX’s Dragon cargo capsule, which served as a precursor to the Crew Dragon, had completed numerous uncrewed cargo missions to the space station over a decade before the Crew Dragon’s launch. This gave SpaceX an advantage as they had a head start with their cargo program, while Boeing had to build their crew vehicle from scratch.
If the Starliner test mission encounters further difficulties, Boeing may find itself in a situation where it needs to rely on its competitor to bring Williams and Wilmore back home.

Lembeck explained, “The embarrassing scenario would be if a Crew Dragon had to go and retrieve the astronauts. The spacecraft could be launched with two crew members and return with four, which would likely be their way back home.”

It is important to note that Boeing emphasizes the independence of the Starliner program from its other divisions, such as the commercial aircraft division that has faced scandals in recent years.

Nappi expressed the seriousness with which Boeing regards human safety during a news briefing in April, prior to the Starliner launch.
Nappi also stated at the time that the Starliner team was operating at their highest level and eagerly anticipating a successful mission.

When questioned about this statement, Stich, a NASA executive, explained that both Boeing and NASA had always anticipated discovering additional issues that needed to be addressed during this test flight.

Williams had hinted at this expectation during a pre-flight press conference, mentioning, “We always come across things, and we will continue to do so. Not everything will be perfect as we navigate the spacecraft… We have great confidence in the safety and reliability of this spacecraft, and we have backup procedures in place if needed,” Williams reassured.
On Tuesday, Stitch admitted that Boeing and NASA could have potentially avoided some of the problems that the Starliner has faced. He suggested that conducting different ground tests to better understand the thruster issues in advance could have been beneficial.

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