Boeing Starliner
The Boeing Starliner is a crewed spacecraft built for transporting NASA astronauts Butch Wilmore and Sunita Williams to the ISS for 8 days. It was launched on June 5 2024 on a cruise called the Crew Flight Test. However, it has been marred by several technical issues, leading to the astronauts being stranded in the ISS until February 2025
Prior to launch, some helium gas leaks were detected on Starliner. It was, however, deemed a minor risk by NASA management upon consultation with Boeing and it launched the astronauts to the ISS.
Starliner’s scheduled date to return the crew back to Earth was postponed to June 18. The original length of stay at the ISS was 8 days. This gave the astronauts prep time for a spacewalk scheduled on June 13 and for ground teams to analyze Starliner. The capsule was only certified to dock at the station for 45 days. This adds up — Boeing is calling back Starliner uncrewed to Earth on autopilot to a designated landing point in New Mexico on September 6.
Helium leaks and RCS thruster faults
It was there that additional helium leaks were found and there were issues with the reaction control system (RCS) thrusters — About 28 RCS thrusters were mounted in the service module. 5 of them were erratic and out of these, 4 of them were brought back online. It was concluded that the thruster problems had no correlation with the helium gas leaks
- [?] Do rocket thrusters contain noble gases such as helium? If yes, what is their purpose? If this is the case, then shouldn’t there be some connection? The ground teams planned to fire all 28 RCS thrusters after undocking to collect more data signatures on service module thrusters before the hardware was expended ← [further clarity required with this sentence] Boeing seemed pretty confident back then, with the following statements
- They said that normally, 7 hours of free-flight time are required to perform a normal end of mission. Starliner had enough helium left for 70 hours of free-flight time
- NASA and Boeing said that because the service module separates from the crew module upon return, they can test the former and gather as much data as possible
Issues with Starliner’s parachutes
It was found that the soft links used on the suspension lines of Starliner’s 3 main parachutes had a failure load limit less than expected. This is a problem because if one chute fails, the other links cannot handle the uneven load distribution. Safe landing with 2/3 chutes is a safety requirement
Flammable wiring tape
The tape protecting the wiring harnesses throughout the Starliner capsule was found to be flammable. I would imagine that without proper fire-retardant systems in place, a tiny spark or change in conditions could start a fire. The lack of thermal insulation in the tape would leave the wiring exposed to potential danger
Audio feedback loop causing strange noises
A strange repetitive noise was heard in the Starliner capsule that is suspected to be the result of a feedback loop between Starliner and the ISS. It shouldn’t be a grave threat as the source of the problem is coming from the digital setup of the capsule and not its electromechanics. The neat “striking a hammer on an iron gong” noise is happening because the capsule is empty and there was a delay of 500 ms.
It has been confirmed that SpaceX’s Crew Dragon spacecraft will bring the astronauts back next year and not Starliner. This apparently humiliated Boeing employees that the “upstart” company SpaceX was tasked with the rescue efforts
External links
- Boeing Starliner Leak Assessment - Space.com
- Boeing’s Starliner spacecraft approaches the International Space Station on its first crewed test flight
- Crewed Starliner Launch Delayed by Flammable Tape, Botched Parachutes
- Boeing employees humiliated that “upstart” company SpaceX was tasked with the rescue efforts
