The National Transportation Safety Board (NTSB), the independent federal agency that carries out investigations into serious airplane crashes, has blocked access to a public docket system after it discovered that internet sleuths have been attempting to reconstruct the cockpit voice audio from the fatal crash of a UPS aircraft at Louisville Muhammad Ali International Airport last November.
NTSB Chairwoman Jennifer Hommendy described the developments as “deeply troubling” and implored social media companies to remove posts that contained the reconstructed cockpit voice recorder audio.
The NTSB makes a wealth of data freely available to the public as part of its investigation process into serious plane crashes, but the agency is legally barred from releasing recordings from cockpit voice recorders due to the “highly sensitive” nature of these communications.
However, it has now come to light that amateur investigators have been using technology to analyse the sound spectrum imagery that is released by the NTSB and reconstruct approximations of the cockpit voice recorder audio.
The visual spectrograms released by the NTSB essentially show frequency content that can be used to identify things like engine sounds, warning tones, mechanical signatures, and impact events.
Advances in technology and artificial intelligence have now allowed individuals who don’t have access to the actual recordings to use these spectrograms to extract approximations of what the pilots were actually saying.
Having discovered how some individuals have been using freely available data to access protected investigative content, the NTSB immediately took action to restrict access to its public docket system.
In a statement, the NTSB explained: “The NTSB is aware that advances in image recognition and computational methods have enabled individuals to reconstruct approximations of cockpit voice recorder audio from sound spectrum imagery released as part of NTSB investigations, including the ongoing investigation of the crash last year of UPS flight 2976 in Louisville, Kentucky.”
The statement continued: “The NTSB does not release cockpit audio recordings. Federal law prohibits such public release due to the highly sensitive nature of verbal communications inside the cockpit. The NTSB takes these privacy restrictions seriously.”
The NTSB was unable to say when the docket system might come back online for public use.
When anyone tries to access the docket system, they are greeted with the following message: “The NTSB docket system is temporarily unavailable as we examine the scope of the issue and evaluate solutions. We hope to restore access to the docket system as soon as possible.”
The UPS crash occurred on November 4, 2025, as an MD-11 freighter plane was taking off from Louisville Muhammad Ali International Airport at around 5:14 pm, bound for Honolulu, Hawaii.
Immediately after the aircraft became airborne, the left engine and pylon assembly separated from the wing, causing the aircraft to burst into flames.
As the plane quickly lost altitude, it tore through the roof of a UPS building at the end of the runway and then exploded into a huge fireball in other nearby buildings. All three pilots on board the plane and 11 people on the ground were killed in the accident. A further 23 people were injured.
The NTSB held an investigative hearing into the crash earlier this week, although a final report into the accident is still some way off.
