Air India crash mystery deepens as tail wreckage reveals signs of electrical malfunction

Investigators probing the deadly crash of Air India flight AI-171 in Ahmedabad are now focusing intently on the tail wreckage of the Boeing 787 Dreamliner, which may hold critical clues to an electrical malfunction moments after take-off. The empennage, or tail section, remained largely intact after the crash and is believed to contain evidence of a “contained electric fire,” according to officials familiar with the investigation.

The aircraft had been airborne for just 26 seconds after departing from Runway 23 at Sardar Vallabhbhai Patel International Airport on June 12 when it lost power and crashed into a building. Though most of the fuselage was engulfed in flames post-crash, the tail section was spared from the full impact of the explosion, preserving essential evidence.

Rear black box ‘beyond salvage’

The aircraft’s rear Enhanced Airborne Flight Recorder (EAFR), or black box, was recovered from the rooftop of a nearby hostel mess but had suffered extensive thermal damage. The Aircraft Accident Investigation Bureau (AAIB), in its July 12 preliminary report, confirmed that the data was “unrecoverable through conventional means” due to severe internal damage to its memory unit.

In contrast, the front black box—retrieved days later from the charred remains—yielded 49 hours of flight data, including audio and digital records from six flights, notably the crash flight. The forward EAFR was covered in soot but remained functional due to its independent power source, unlike the rear black box which relied on the aircraft’s main electrical system.

“The aft black box is designed to withstand impact and fire. The extent of damage observed here is highly unusual and concerning,” an official said.

Possible pre-flight fault in tail sensor

Adding weight to the theory of an in-flight electric malfunction is a defect recorded just before the doomed flight. Crew members from the preceding Delhi-to-Ahmedabad flight (AI-423) had logged a defect in the aircraft’s stabilizer position transducer—a sensor critical for flight control located in the tail section. Though the issue was reportedly resolved by engineers before take-off, it is now under renewed scrutiny.

Investigators have safely stored components from the tail, including the Auxiliary Power Unit (APU), transducers, and rudders. The APU, essential during take-off in high-temperature conditions, was found intact and may have been running during the incident, officials said.

“A malfunction in electrical systems during the ground roll could have triggered cascading failures—sending erroneous signals to the Engine Control Unit (ECU) and causing it to cut off fuel supply. That’s what we’re trying to confirm,” said one source familiar with the analysis.

FADEC and fuel cut-off under the lens

Central to the investigation is the FADEC (Full Authority Digital Engine Control) system — the “brain” of the aircraft — which monitors and manages engine functions. Data retrieved from the front black box shows that both engines abruptly lost fuel supply within seconds of lift-off. This “uncommanded” fuel cut-off, now believed to have been triggered by cascading system errors, is a focal point of the probe.

“FADEC systems are programmed to shut off fuel flow to protect the engines during system anomalies. The question is, what triggered that response in the first place?” the official said.

Cabin lights flickered before crash: lone survivor

Survivor Viswashkumar Ramesh’s testimony adds a human dimension to the technical mystery. He recalled flickering cabin lights moments before the crash, which investigators believe could indicate a switch between power sources — main, backup, and an attempted relight—within seconds.

“This aligns with the theory of an electrical systems failure. It wasn't just one glitch; multiple systems could have been miscommunicating in a catastrophic loop,” an official said.

APU history, 2013 grounding revisited

Officials also referenced the history of APU-related malfunctions in Boeing 787 Dreamliners. In 2013, the global fleet was grounded after battery issues led to fires. The aircraft involved in the AI-171 crash was commissioned after FAA-approved design upgrades. Now, that same component — the APU and its batteries — is under forensic examination once again.

Flight attendant's death may support electrical fire theory

The body of a flight attendant, recovered 72 hours after the crash from the rear crew deck area, was found in a decomposed state but with limited burn injuries. Unlike passengers who perished in the post-crash inferno, she appeared to have succumbed to impact injuries and a minor fire isolated to the tail section.

“She wasn’t charred like the others. The burns came from a brief, contained fire likely caused by the aircraft’s electrical system — not the explosion,” a Gujarat government official said.

What happens next

The investigation is now zeroed in on the events between the initial roll on the runway and the 26 seconds of flight that followed. Key to solving the mystery will be the damaged rear black box, stabilizer sensors, APU functionality, and analysis of FADEC behavior in those critical moments.

The findings may shape global scrutiny once again over Dreamliner systems and their response to electrical or sensor failures — especially under extreme conditions. A final report is expected after in-depth lab testing of salvaged components.