Air India crash: How US golden chassis aided recovery of black box data and audio

The devastating crash claimed 260 lives, 242 onboard and 19 on the ground, leaving just one survivor.

A specialised device known as the Golden Chassis, sourced from the U.S., played a key role in retrieving critical flight data from one of the black boxes of the ill-fated Air India flight AI171, which crashed shortly after takeoff from Ahmedabad on June 12.

Investigators from the Aircraft Accident Investigation Bureau (AAIB) retrieved two black boxes, enhanced airborne flight recorders (EAFRs), and transported them to New Delhi on June 24.

Owing to damage sustained during the crash, India reached out to the US National Transportation Safety Board (NTSB) for assistance. The NTSB supplied the Golden Chassis and specialised download cables required to extract data from the black boxes.

The devastating crash claimed 260 lives, 242 onboard and 19 on the ground, leaving just one survivor.

According to the AAIB preliminary crash report, the Crash Protection Module (CPM) from the forward EAFR was intact and successfully mounted on the Golden Chassis. This, in turn, enabled investigators to download 49 hours of flight data, covering six flights, including the doomed June 12 flight.

Additionally, two hours of cockpit voice recordings, including crucial audio from the crash sequence, have been recovered and analysed.

The rear EAFR, however, was too severely damaged to recover any data using conventional methods. The memory card within was found to be extensively compromised.

A multi-disciplinary investigation team has been formed, led by Investigator-in-Charge Sanjay Kumar Singh and Chief Investigator Jasbir Singh Larhga. The team also includes experts in aviation medicine, psychology, engineering, flight operations, and flight data analysis.

According to the AAIB’s 15-page preliminary report released early Saturday, both engines lost power within 90 seconds of takeoff after their fuel control switches were moved from “RUN” to “CUTOFF” within a single second.

The cockpit voice recorder captured one pilot asking, “Why did you cut off?”, to which the other responded, “I did not.”

The loss of thrust caused the London-bound Boeing 787 Dreamliner to plunge into a nearby medical college hostel, resulting in India’s deadliest aviation accident in over a decade.

Aviation professionals were quick to question how both fuel switches could have been inadvertently flipped, pointing out the built-in mechanical gate that makes accidental shutoff difficult.

Some experts also raised concerns over the lack of cockpit video analysis in the report.

Air India, meanwhile, in response to the findings, has pledged to involve its pilot community in safety reviews. In a communication to pilots, Manish Uppal, Senior Vice President for Flight Operations, acknowledged the gravity of the incident and stated that the airline would hold sessions to review the report collectively.

“This is not the final word, but an important step toward identifying contributing factors and ensuring corrective action,” Uppal said. “We must reflect, react, and rise stronger.”

Furthermore, the Airline Pilots Association of India has criticised the preliminary findings, calling the investigation “shrouded in secrecy” and potentially biased against the crew. The association questioned how investigators reached conclusions so quickly and without public transparency.

The AAIB has stated that the investigation is currently underway, with further analysis to be conducted in collaboration with the UK’s Air Accident Investigation Branch and the US NTSB.