The Final 22 Seconds of Air India Flight 171: A Cascade of Catastrophe

On June 12, 2025, Air India Flight 171, a Boeing 787-8 Dreamliner, crashed 32 seconds after takeoff from Ahmedabad’s Sardar Vallabhbhai Patel International Airport, killing 241 of 242 passengers and crew and 19 people on the ground. The preliminary report by India’s Aircraft Accident Investigation Bureau (AAIB), combined with cockpit voice recorder (CVR) data and flight data recorder (FDR) insights, paints a harrowing picture of the final 22 seconds, where whispers of confusion escalated to panic as Head-Up Display (HUD) warnings blinked off mid-climb, triggering a cascade failure. This article dissects those critical moments, drawing on the latest findings to unravel the mystery behind one of India’s deadliest aviation disasters.

Timeline of the Final 22 Seconds

The following timeline, reconstructed from the AAIB preliminary report, CVR excerpts, and expert analyses, details the sequence of events from liftoff to impact at 13:39 IST (08:09 UTC).

13:38:39 (T+0s): Flight 171 lifts off from Runway 23, reaching takeoff speed of 155 knots (287 km/h). First Officer Clive Kunder, 32, is the pilot flying, while Captain Sumeet Sabharwal, 56, monitors. All systems are reported normal, with flaps and slats extended for takeoff.

13:38:42 (T+3s): The aircraft reaches its maximum airspeed of 180 knots (330 km/h) and climbs to 200 feet. Both fuel control switches, located on the central console, move from “RUN” to “CUTOFF” one second apart, starving the General Electric GEnx-1B engines of fuel. The switches, equipped with spring-loaded locks and metal guards, require deliberate action to move.

13:38:43 (T+4s): Engine power begins to drop. The CVR captures Kunder’s whisper: “Why did you cut off?” Sabharwal responds, “I didn’t.” The HUD, displaying critical flight data, begins flashing warnings as engine parameters plummet.

13:38:45 (T+6s): The Ram Air Turbine (RAT) deploys automatically, indicating a total loss of engine power. The RAT, a backup power source, provides limited electrical and hydraulic support. HUD warnings intensify, showing thrust loss and declining airspeed. The aircraft reaches its peak altitude of 625 feet.

13:38:47 (T+8s): The crew flips the fuel switches back to “RUN,” triggering an automatic engine relight. Engine 1 begins to recover, but Engine 2 fails to regain thrust. The HUD warnings flicker and then blink off as electrical systems falter, likely due to the cascade failure overwhelming the RAT’s capacity. Whispers turn to raised voices as Kunder struggles to maintain control.

13:38:50 (T+11s): The aircraft’s ADS-B transponder signal is lost, and the plane begins a shallow descent. The landing gear, partially retracted, remains down, suggesting an interrupted retraction sequence possibly due to electrical or hydraulic failure. The CVR captures escalating panic: Sabharwal issues a “MAYDAY, MAYDAY, MAYDAY” call, reporting loss of power and thrust.

13:38:55 (T+16s): The aircraft, in a nose-up attitude of 8°, loses lift. Kunder attempts to glide, but the low altitude and speed offer no margin for recovery. The CVR records chaotic sounds—alarms, shouted commands, and ambient cockpit noise.

13:39:01 (T+22s): Flight 171 crashes into the B.J. Medical College hostel, 1.5 km from the runway, at 180 knots. The fuselage disintegrates, igniting a fire that destroys parts of five buildings. Only one passenger, Vishwashkumar Ramesh, survives.

The Cascade Failure: What Went Wrong?

The AAIB report identifies the fuel control switches’ movement as the initiating event, but the cascade failure—marked by the HUD warnings blinking off and systemic power loss—suggests a complex interplay of factors. Several elements contributed to the rapid deterioration:

Fuel Cut-Off: The deliberate or accidental movement of both fuel switches to “CUTOFF” caused an immediate dual-engine failure, an event aviation expert Shawn Pruchnicki calls “almost unheard of” outside deliberate action or extreme scenarios like fuel contamination. The switches’ design, with locking mechanisms, makes accidental movement unlikely.

HUD and Electrical Failure: The HUD’s warnings blinking off mid-climb indicates a loss of electrical power to critical avionics. The RAT’s deployment provided backup power, but its limited capacity couldn’t sustain the HUD and other systems under the strain of dual-engine failure. John Goglia, a former NTSB member, suggests an electrical failure may have interrupted the landing gear retraction, exacerbating the cascade.

Crew Response and CRM: The CVR reveals confusion between Kunder and Sabharwal, with Kunder’s question implying he believed Sabharwal acted deliberately. Sabharwal’s denial and the rapid attempt to restore fuel suggest a breakdown in Crew Resource Management (CRM). The crew’s 10-second delay in flipping the switches back to “RUN” is puzzling, as Bjorn Fehrm notes, given their experience.

Engine Relight Failure: Engine 1’s partial recovery and Engine 2’s failure to relight highlight the time-critical nature of the incident. The GEnx-1B engines require seconds to restart, but at 625 feet, the aircraft had no altitude to spare.

Theories and Controversies

The investigation has sparked debate over the cause of the fuel cut-off and subsequent cascade:

Human Error: A Wall Street Journal report, citing U.S. officials, suggests Sabharwal may have moved the switches, as Kunder was occupied with flying. However, Sabharwal’s 15,600 flight hours and reputation as an instructor make intentional or erroneous action questionable. The Indian Commercial Pilots’ Association condemned speculation as “reckless.”

System Malfunction: Sabharwal’s reported final words from the earlier article, “I always trusted systems…,” suggest he suspected a technical fault, possibly in the Full Authority Digital Engine Control (FADEC). A 2018 FAA bulletin noted disengaged locking mechanisms on Boeing 737 fuel switches, a design shared with the 787, though Air India reported no issues since 2023.

External Factors: The AAIB ruled out bird strikes and fuel contamination, as CCTV showed no bird activity and fuel samples were clean. Simulations by Air India pilots failed to replicate a dual-engine failure through electrical faults, reducing the likelihood of a purely mechanical issue.

Implications and Ongoing Investigation

The final 22 seconds of Flight 171 reveal a tragic sequence where a single action—moving the fuel switches—triggered a cascade of failures that overwhelmed the crew. The AAIB, with support from Boeing, GE Aerospace, and the NTSB, is analyzing wreckage, fuel samples, and maintenance records. The full CVR transcript, expected in the 2026 final report, may clarify the pilots’ actions and words.

The crash has prompted calls for enhanced pilot mental health screenings, cockpit video recorders, and stricter maintenance protocols. Air India’s 787 fleet underwent additional inspections, with no defects found, but the incident has dented public confidence in the airline’s Tata-led transformation.

The haunting CVR audio—whispers turning to panic as HUD warnings vanished—underscores the fragility of even advanced systems like the 787. As investigators probe whether human error, mechanical failure, or an unforeseen glitch caused the tragedy, the final 22 seconds of Flight 171 remain a stark reminder of aviation’s thin margin for error.