🔍 Air India Flight 171 Disaster: What the Preliminary Investigation Reveals About Its Shocking Cause

Introduction

The aviation world was shaken in June 2025 when Air India Flight 171, a Boeing 787-8 Dreamliner en route from Ahmedabad to London, crashed shortly after takeoff—claiming the lives of all 241 passengers and crew on board, as well as 19 people on the ground. It was the deadliest aviation tragedy in India’s recent history and the worst worldwide since 2018.

In the aftermath, investigators rushed to determine what could have caused a modern, well-maintained aircraft with experienced pilots to fail within minutes of departure. Now, weeks later, the preliminary accident report from India’s Aircraft Accident Investigation Bureau (AAIB) offers chilling insight into a catastrophic sequence of cockpit actions—yet many questions remain unanswered.

This article explores the known facts, key findings from the early report, technical analysis, and public response to one of the most disturbing aviation disasters in recent memory.

The Crash: Timeline of Events

June 12, 2025 – 4:17 AM: Flight AI171 takes off from Ahmedabad’s Sardar Vallabhbhai Patel International Airport en route to London Heathrow.
Just after takeoff: According to recovered flight data, both engines suddenly lose power.
Seconds later: The aircraft pitches downward, stalls, and crashes into a residential neighborhood just 3.7 nautical miles from the airport.
Casualties: All 241 onboard perish. 19 people on the ground are also killed, with dozens more injured.

The cockpit voice recorder (CVR) and flight data recorder (FDR) were recovered within hours. Their data is at the center of the current investigation.

Key Findings from the Preliminary Report

🚨 Engine Shutdown Was Not Mechanical

Contrary to initial fears of technical malfunction, the investigation found no signs of mechanical failure, engine damage prior to impact, or adverse weather.

Instead, data shows that both engine fuel-control switches were manually set to “CUTOFF” just after takeoff—a highly unusual and dangerous action. These switches, located between the pilots, cut fuel supply to the engines when activated.

This critical action effectively shut down the engines mid-climb, causing total thrust loss at low altitude—a nearly unrecoverable situation.

💬 Cockpit Voice Recorder: “Why Did You Cut Off?”

The CVR recording adds emotional weight and mystery. At the moment of engine shutdown, one of the pilots can be heard asking:

“Why did you cut off?”

The other responds with confusion or denial, saying:

“What? I didn’t.”

The exchange has fueled intense speculation: Was it an accident? A misunderstanding? Or something else entirely?

How the Fuel-Control Switches Work

The fuel-control switches are heavy-duty levers with resistance to accidental movement.
They are used primarily during engine shutdown on the ground or in extreme emergencies.
Moving one—or both—requires deliberate force.
The AAIB notes it is “highly improbable” that both switches were toggled accidentally during climb-out.

This has led many experts to rule out a purely accidental shutdown, though intent has not been established.

No Evidence of Sabotage or External Tampering

Investigators also ruled out:

Fuel contamination – No issues found with pre-flight fueling procedures.
Weight imbalance – Aircraft was well within operational limits.
Weather – Clear skies, no wind shear or turbulence.
Bird strike or external collision – Not supported by radar or physical evidence.

Additionally, no third-party sabotage has been indicated. Maintenance logs showed no red flags in the days leading up to the flight.

FAA Advisory: Switch Locking Mechanism Concerns

A 2018 FAA safety bulletin warned operators of a rare defect in the locking mechanism of similar fuel-control switches. Though not considered urgent at the time, it advised routine checks and possible retrofitting.

According to the report, Air India did not install upgraded locks, as the advisory was non-mandatory.

The AAIB is exploring whether a mechanical anomaly in the switch mechanism may have contributed—although no such failure was found in wreckage analysis.

The Pilots: Experienced but Under Review

The captain and first officer had over 15,000 and 3,400 flight hours, respectively—both rated for the 787 Dreamliner.

Investigators confirmed:

The captain was flying the aircraft.
The co-pilot was handling radio and checklists.

Psychological evaluations showed no prior signs of instability, and both passed their most recent medicals.

However, in the absence of cockpit video (which is not mandatory), determining who moved the switches and why remains inconclusive.

Ram Air Turbine Deployment: Sign of Power Loss

Bakit nangyari ito at mayroon bang mga nakaligtas mula sa pagbagsak ng  eroplano ng Air India! Narito kung ano ang kilala - Gazeta Express

Footage from nearby security cameras shows a Ram Air Turbine (RAT) deploying midair—a small propeller that automatically extends during engine failure to power essential flight systems.

This confirms that the engines were indeed fully off before the crash.

Public and Industry Response

The shocking nature of the findings has drawn strong reactions from:

✈️ Aviation Professionals

Pilot associations have urged caution, warning the public and media not to jump to conclusions.

“We are deeply saddened by the loss of life. But early speculation about pilot error or intent is both unethical and damaging.”
— Indian Commercial Pilots Association (ICPA)

Many call for the implementation of cockpit video recorders to provide clearer context in future investigations.

💔 Families of the Victims

Families have expressed frustration over the uncertainty:

“We don’t want to hear ‘manual action’ without an answer to why. We need to know the truth, not just technical jargon.”
— Relative of one passenger from Mumbai

A compensation process has begun, but legal action is expected, depending on final report findings.

Was It Intentional? A Painful Possibility

Aviation experts say the report’s current language leaves open the possibility of human action—whether deliberate, mistaken, or the result of confusion in the cockpit.

Intentional fuel shutoff is extremely rare, but not unprecedented. In aviation history, there have been a handful of events where pilot error, miscommunication, or even rare instances of sabotage played roles in mid-flight disasters.

No such determination has yet been made in this case. Investigators are examining:

The cockpit CRM (crew resource management) dynamics.
The pilots’ training history and personal backgrounds.
Psychological screenings and recent behaviors.

What Happens Next

The AAIB, along with Boeing, the FAA, and India’s DGCA, continue to analyze data. The final report, under international ICAO guidelines, is expected within 12 months.

Possible outcomes include:

Mandatory cockpit video recorders in India.
Review of switch design and location.
Revisions to training on emergency switch use.
Civil or criminal proceedings, if intent is found.

Summary of Key Facts

Aspect
Status / Details

Aircraft model
Boeing 787-8 Dreamliner

Flight
AI171 – Ahmedabad to London

Date of crash
June 12, 2025

Casualties
260 total (241 onboard, 19 on ground)

Engine failure cause
Fuel-control switches moved to “CUTOFF”

Mechanical failure
None found

Fuel contamination
None found

Switch movement
Confirmed deliberate (requires force); cause unclear

Cockpit exchange
“Why did you cut off?” – “I didn’t.”

FAA advisory status
Switch locking issue flagged in 2018; no retrofit by Air India

Final report due
Within 12 months (by mid-2026)

Possible contributing factors
Human error, design oversight, or cockpit miscommunication

Conclusion

The Air India Flight 171 disaster is a reminder that even in the modern age of aviation, mystery can still surround catastrophe. While the early findings provide technical clarity, the human dimension—why the switches were moved, and by whom—remains hauntingly unanswered.

Until the final report is published, and more context is available, it’s important to avoid speculation while honoring those who lost their lives. Transparency, patience, and a commitment to truth will be crucial in finding both closure and lessons that can prevent future tragedies.

Related Articles (for Further Reading):

Aviation Disasters Caused by Human Error: A Global Review
What Is a Ram Air Turbine and Why Does It Matter in Engine Failures?
Boeing 787 Dreamliner: Safety Record and Design Analysis
The Debate Over Cockpit Cameras: Should They Be Mandatory?
Understanding Aircraft Fuel Systems: How Manual Overrides Work