NASA identifies strange sound from Boeing's faulty Starliner
NASA has identified the source of strange, 'sonar-like' sounds coming from inside Boeing's Starliner capsule, and says that the noises have stopped as of now.
In an emailed statement, a NASA press officer told DailyMail.com that the cause was 'an audio configuration between the space station and Starliner.'
The space agency had been searching for the source of the sounds since Saturday, when stranded astronaut Butch Wilmore radioed down to Johnson Space Center in Houston to report a mysterious pulsing noise coming from one of the spacecraft's speakers.
'I've got a question about Starliner. There's a strange noise coming through the speaker and I didn't know if you can connect into the Starliner... I don't know what's making it', he said.
An audio configuration issue could mean a lot of different things, but a retired NASA scientist told DailyMail.com that NASA is likely referring to a signal feedback loop.
Astronaut Butch Wilmore reported 'strange' sonar-like sounds coming from Boeing's Starliner capsule on Saturday.
'It could have been that the electronics they have just happened to produce a pulsing effect when there was feedback,' former NASA planetary physicist Phillip Metzger, who previously tested intercom systems on the International Space Station, told DailyMail.com.
An audio feedback loop occurs when an audio signal is sent from an input to an output, and then back to itself, creating a loop of sound.
Often, it sounds like a steady howling or screeching sound that gets consistently louder as the looping continues - quite unlike the steady pulsing that Wilmore heard.
'But depending on the electronics, it might not do that,' Metzger said. 'Depending on the kind of filtering they have, it might produce some other effect.'
Therefore, it's still plausible that this sound could have stemmed from a feedback loop.
Both Metzger and NASA confirmed that this issue should not affect any of Starliner's other systems, and should not pose any safety risks or interfere with the spacecraft's functionality.
Prior to NASA's statement, Metzger took to X, formerly Twitter, to speculate that the cause of the sound could be electromagnetic interference, or EMI.
2/2 For Space Station, I tested the intercom systems among other things. Electromagnetic interference (EMI) is very common and hard to eliminate. During one test, we were hearing noise that we finally traced to the power inverters that were part of the test facility, not even in…
— Dr. Phil Metzger (@DrPhiltill) September 1, 2024
EMI occurs when stray electromagnetic signals get into an electronic system, like Starliner's auditory system, he explained.
The cables inside a spacecraft's electronic systems are wrapped in braided 'shielding' that prevents EMI from entering the system.
But sometimes, these shield can break. This is especially common near a system's connectors - 'that's the weak point where things tend to break,' Metzger said.
Shielding can break down due to vibration, which may cause a braided wire to rub up against the machinery and fray over time. Or, it could be due to a design or manufacturing issue, he explained.
'If that little fine braided material breaks, then it creates an opening for the signal to get in,' Metzger said.
It is still possible that the unusual sounds coming from Starliner's speaker were caused by EMI, but based on the NASA statement, Metzger thinks a feedback loop is an equally likely explanation.
This audio issue should not impact Starliner's ability to undock from the ISS and begin its uncrewed return to Earth on September 6.
'The space station audio system is complex, allowing multiple spacecraft and modules to be interconnected, and it is common to experience noise and feedback,' NASA wrote in their statement.
This latest technical snafu comes just four days before Starliner is scheduled to undock from the ISS and begin its uncrewed return to Earth, leaving astronauts Sunita Williams and Butch Wilmore on the ISS for at least six more months.
Wilmore and Williams have been marooned on the ISS since June 6 when they arrived on Boeing's spacecraft for what was supposed to be a week-long stay.
Starliner was plagued by helium leaks and thruster issues before, during and after the launch. On August 24, NASA officials decided that the faulty spacecraft was unfit to carry its crew back to Earth.
Instead, Wilmore and Williams will remain on the ISS until February 2025, when they can hitch a ride home on SpaceX's Crew Dragon spacecraft.
As for Starliner, NASA has chosen a date and time no earlier than 6:04 PM on September 6 to undock the spacecraft from the ISS and return it to Earth.
As long as the weather is clear for the landing site, Starliner will autonomously undock from the ISS and begin a six-hour flight to a desert landing target of White Sands Space Harbor in New Mexico.
After the landing, it will be shipped back to Boeing's Starliner factory at Kennedy Space Center.
