Dr. Subhash Kumar
Former, General Manager (Fire Service & Fire Training),
Chairman, Indian Aviation Fire Safety Specialist Group


1. OVERVIEW OF THE ACCIDENT

On June 12, 2025, Air India Flight AI171, a Boeing 787-8 Dreamliner registered as VTANC, met with a catastrophic accident shortly after departing from Sardar Vallabhbhai Patel International Airport (SVPIA) in Ahmedabad, Gujarat, India. The flight was bound for London Heathrow Airport (LHR) with 231 passengers and 11 crew members on board, totaling 242 individuals. At approximately 1:38 p.m. IST, just minutes after takeoff, the aircraft crashed into the densely populated Meghani Nagar residential area, colliding with a multi-story residential block and the doctors' hostel at BJ Medical College. The impact and subsequent secondary explosions, fueled by the aircraft’s near-full fuel tanks, resulted in 270 fatalities, including 241 on board and 29 ground victims. The sole survivor, Vishwashkumar Ramesh, a 32-year-old passenger seated at 11A near an emergency exit, sustained critical injuries but provided vital firsthand accounts of the moments before the crash. His survival, attributed to his proximity to a survivable void in the wreckage, has shaped early survivor-based narratives and highlighted the importance of emergency exit seating. The crash site’s urban location amplified the tragedy, raising questions about zoning regulations and airport proximity to residential areas.


2. AIRCRAFT AND FLIGHT INFORMATION

Aircraft Age and Configuration: The Boeing 787-8 Dreamliner involved was delivered to Air India in 2013, making it approximately 11.5 years old at the time of the accident. It had accumulated over 30,000 flight hours and completed more than 700 flights in the 12 months prior to June 2025, reflecting a high operational tempo. The aircraft was configured with 18 business-class seats and 238 economy-class seats, typical for Air India’s long-haul international routes. Maintenance records indicate compliance with Boeing’s recommended service intervals, though the high cycle count prompted scrutiny of fatigue-related wear on critical systems. 

Engine Type: The aircraft was powered by two General Electric GEnx-1B engines, known for their advanced composite fan blades and fuel efficiency, achieving up to 20% better fuel economy compared to older models like the 767. These engines were subject to routine inspections, with no reported anomalies in the pre-flight checks conducted on June 12, 2025. Post-accident analysis focused on engine performance data to rule out thrust-related failures.

Route: Flight AI171 was scheduled to cover approximately 6,800 km from Ahmedabad (AMD) to London Heathrow (LHR), with a planned flight duration of 9 hours and 15 minutes. The route involved crossing the Arabian Sea, Middle Eastern airspace, and Europe, with an initial climb to cruising altitude of 36,000 feet. The flight was operating under visual meteorological conditions (VMC) at takeoff, with no anticipated weather-related challenges en route.

3. SEQUENCE OF EVENTS LEADING TO THE CRASH

Take-off and Initial Climb: The aircraft departed from Runway 23 at SVPIA at 1:36 p.m. IST, following standard takeoff procedures. Air traffic control (ATC) transcripts confirm clearance for a standard instrument departure (SID). The aircraft reached an altitude of approximately 625 feet above ground level (AGL) within 45 seconds, consistent with normal climb performance for a 787-8. However, radar data indicates an abrupt deviation from the expected climb profile shortly thereafter.

Distress Call: At 1:37 p.m., less than a minute after takeoff, the crew issued a Mayday call, signaling an immediate emergency. The call, recorded by ATC, was brief and lacked specific details about the nature of the issue, suggesting the crew was preoccupied with managing a critical situation. Analysis of the call’s timing aligns with the onset of abnormal flight behavior observed in radar data.

Flight Behaviour: Flight Data Recorder (FDR) preliminary extracts reveal an abnormal nose-up pitch angle exceeding 20 degrees, far beyond standard takeoff parameters. The landing gear remained extended, contrary to standard procedure, and there is evidence suggesting the flaps may not have been extended to the appropriate takeoff setting. Witnesses on the ground reported seeing the aircraft in a steep climb with visible gear, followed by a sudden roll to the right. This behavior is consistent with a potential stall or loss of lift, possibly exacerbated by incorrect configuration or system failure.

Impact: At approximately 1:38 p.m., the aircraft impacted Meghani Nagar, a residential area 3.5 km from the runway threshold. The crash site spanned 200 meters, with the main wreckage concentrated around a collapsed four-story apartment building and the adjacent doctors' hostel. The aircraft’s full fuel load, estimated at 80,000 kg for the long-haul flight, ignited on impact, causing secondary explosions and a fire that hampered rescue efforts. Debris analysis suggests the aircraft struck the ground at a shallow angle of 10–15 degrees, with significant forward momentum.


4. NATIONAL INVESTIGATIVE FRAMEWORK

Lead Agency: The Aircraft Accident Investigation Bureau (AAIB), under India’s Ministry of Civil Aviation, is the primary authority overseeing the investigation. Established under the Aircraft (Investigation of Accidents and Incidents) Rules, 2017, the AAIB is tasked with determining the probable cause and recommending safety enhancements. The agency deployed a 15-member team to the crash site within hours, coordinating evidence collection and witness interviews.


Supporting Agencies: The investigation involves multiple stakeholders:

•Directorate General of Civil Aviation (DGCA): Provides regulatory oversight and audits Air India’s operational and maintenance practices.

• Air India Engineering Services Ltd (AIESL): Supplies maintenance records and technical expertise on the 787 fleet.

• Boeing Commercial Airplanes (USA): Assists with airframe and system analysis, given the 787’s design origin.

• General Electric (GE Aerospace): Supports engine performance evaluation, focusing on GEnx-1B data.

• U.S. National Transportation Safety Board (NTSB) and UK Air Accidents Investigation Branch (AAIB): Contribute expertise due to the involvement of American-designed aircraft and British victims, respectively. Their participation ensures compliance with ICAO Annex 13 protocols for international accidents.

5. EVIDENCE COLLECTION AND TECHNICAL EVALUATION

Black Box Recovery: Flight Data Recorder (FDR): Recovered on June 13, 2025, from the tail section of the wreckage, the FDR was largely intact. It was transported to AAIB’s laboratory in New Delhi, where data extraction began under NTSB supervision. The FDR records over 1,000 parameters, including flight control inputs, engine performance, and system statuses, providing a detailed timeline of the aircraft’s final minutes.

Cockpit Voice Recorder (CVR): Retrieved on June 14, 2025, the CVR sustained significant damage due to fire exposure. It was sent to a specialized forensic audio recovery facility in the U.S., where efforts are underway to extract usable audio. The CVR captures the last 30 minutes of cockpit communications, critical for understanding crew actions and potential alerts from onboard systems.

Wreckage Analysis: 3D map of the crash site was created using drone-based photogrammetry, enabling precise documentation of debris distribution. The wreckage pattern indicates a low-angle impact with the right wing striking first, followed by fuselage disintegration.

Examination of the wing and fuselage revealed extensive fracturing of the 787’s composite structure, consistent with high-energy impact. Hydraulic lines showed signs of pre-impact compromise, potentially affecting flight control surfaces or landing gear operation.

Key components, including flap actuators and landing gear assemblies, were recovered for laboratory analysis to determine their operational status at the time of the crash.

6. OPERATIONAL AND HUMAN FACTORS ANALYSIS

Pilot Credentials:

  • Captain Ajay Bhargava: Aged 52, with over 12,000 flight hours, including 3,800 on the Boeing 787. He was a check pilot, authorized to train and evaluate other 787 pilots. His last proficiency check, conducted in April 2025, showed no deficiencies.
  • First Officer: Aged 34, with 2,500 total flight hours, including 300 on the 787. Recently transitioned from the Airbus A320, the first officer was under mentorship as part of Air India’s type-rating program. Simulator records confirm satisfactory performance in high-workload scenarios.

Possible Errors: Investigators are exploring whether the crew failed to extend flaps to the correct takeoff setting (typically Flaps 5 or 10 for a 787). A misconfigured flap setting could reduce lift, leading to the observed steep pitch and potential stall.

The extended landing gear suggests either a procedural oversight or a mechanical issue preventing retraction. FDR data indicates no retraction command was issued, raising questions about crew situational awareness or system feedback.

Crew Fatigue: The DGCA’s Cabin Safety Division is auditing crew rest records. The flight was the third leg of a multi-sector roster for the crew, with a 14-hour rest period in Ahmedabad prior to departure. While compliant with DGCA regulations, cumulative fatigue from prior sectors is under review, as it may have impaired decision-making during the emergency.

Maintenance Oversight: The aircraft underwent an A-check (a routine maintenance inspection) on June 2, 2025, at Air India’s Mumbai facility. No major discrepancies were reported, but a minor hydraulic fluid leak noted in May 2025 was addressed.

Post-accident scrutiny flagged potential wear on flap actuators, which may have been overlooked during inspections. Maintenance logs are being cross-referenced with Boeing’s service bulletins to identify any missed critical updates.

7. AIRCRAFT SYSTEMS AND PERFORMANCE EVALUATION

Flight Control System: FDR data revealed anomalies in pitch trim settings, with the aircraft’s automatic trim system commanding excessive nose-up inputs. This could indicate a fault in the Primary Flight Control Computer (PFCC) or erroneous sensor data.The Backup Flight Control Module (BFCM), designed to provide redundancy, is under evaluation by Boeing to determine whether it activated correctly. Discrepancies in BFCM logs could point to a software or hardware issue.

Landing Gear: The landing gear was found in the extended position, despite the aircraft being in climb phase. Hydraulic pressure readings suggest a possible lock in the gear’s hydraulic circuit, preventing retraction. Alternatively, the crew may have intentionally left the gear extended if they perceived a malfunction requiring immediate return to the airport. Gear position sensors are being tested to rule out false indications that might have misled the crew.

Flaps and Actuators: Maintenance records confirm the replacement of a flap actuator in January 2025, following a reported sluggish response during a routine check. The new actuator passed post-installation tests, but investigators suspect a sensor or relay failure may have caused incorrect flap positioning during take-off. Flap position data from the FDR is being compared with cockpit switch settings to determine whether the issue was mechanical or procedural.

Engine Thrust: Visual inspection of the GEnx-1B engines showed no evidence of bird strikes, foreign object damage, or internal failure. Engine telemetry indicates both engines were operating within normal parameters until impact. A slight thrust asymmetry (2–3% difference between engines) was noted in FDR data, but it is unlikely to have caused the crash. GE Aerospace is analyzing fuel flow and compressor performance to confirm engine stability.

8. ENVIRONMENTAL AND INFRASTRUCTURE CONSIDERATIONS

Weather: At the time of the accident, Ahmedabad reported clear skies with a temperature of 34°C, humidity of 65%, and visibility of 6 km. Surface winds were light at 5 knots from the southwest, with no reports of wind shear or turbulence. Weather data from METAR reports and satellite imagery corroborate benign conditions, ruling out environmental factors as a primary cause.

Airport Facilities: Runway 23 at SVPIA, measuring 3,505 meters, was equipped with a Category I Instrument Landing System (ILS) and a functioning glide slope. Preflight checks by airport authorities confirmed all navigational aids were operational. The runway surface was inspected post-accident, revealing no foreign object debris (FOD) or pavement issues that could have affected takeoff.

Urban Encroachment: The crash site in Meghani Nagar, located within 4 km of the airport, falls within a high-density residential zone. Indian regulations require a 3-km buffer around airports, but enforcement has been lax in Ahmedabad due to rapid urban expansion. The proximity of residential buildings to the flight path amplified ground casualties and complicated emergency response. The Ministry of Urban Development has launched a review of zoning violations, with potential implications for other Indian airports.

9. SYSTEMIC DEFICIENCIES AND INSTITUTIONAL GAPS

DGCA Oversight: The DGCA initiated a special audit of Air India’s Boeing 787 operations, focusing on compliance with maintenance, training, and safety protocols. Preliminary findings highlight lapses in emergency response training, including outdated cabin crew evacuation drills. The regulator is also examining whether staffing shortages at Air India’s safety department contributed to oversight gaps.

Organizational Safety Culture: Air India’s safety management system (SMS) has been criticized for slow adoption of recommendations from prior DGCA audits. A 2023 audit flagged deficiencies in crew resource management (CRM) implementation, but only 60% of recommended changes were completed by June 2025. Internal resistance and resource constraints reportedly delayed full compliance.

Training Programs: Air India’s pilot training program includes regular simulator sessions, but recent records show limited focus on low-altitude emergency scenarios, such as takeoff configuration errors or stall recovery at low speeds. CRM training, critical phases of flight training, and which emphasizes crew coordination, was last updated in 2022, missing newer industry standards for high-workload scenarios. The DGCA is pushing for mandatory low-altitude stall training and enhanced CRM modules across all Indian operators.

10. CRASHWORTHINESS AND RESCUE ASSESSMENT

Structural Integrity: The Boeing 787’s composite fuselage, while lightweight and corrosion-resistant, fragmented extensively upon impact due to the high-energy crash. The survivable void near seat 11A was created by a combination of the reinforced emergency exit doorframe and a section of the overhead bin that absorbed impact forces. The rapid disintegration of the fuselage and cabin precluded survival for most occupants.

Rescue Operations: The immediate post-crash fire, fueled by approximately 60,000 kg of remaining jet fuel, created a hazardous environment for rescue operations. Airport Fire Service arrived and Local fire services arrived within 30 minutes, but the intensity of the blaze delayed access to the wreckage. The lack of adequate fire-resistant equipment and poor road access in Meghani Nagar further hampered efforts. The sole survivor, Mr. Vishwashkumar Ramesh, was extracted by nearby civilians before professional responders arrived, highlighting gaps in coordinated emergency response.


Emergency Response: Analysis of seatbelt usage is ongoing, with preliminary data suggesting that most passengers, including the survivor, had their seatbelts fastened. The crash’s severity rendered evacuation procedures irrelevant, as the aircraft was destroyed before slides or exits could be deployed. Oxygen masks were not deployed, consistent with the low-altitude, short-duration nature of the event.

11. INTERNATIONAL COLLABORATION

Data Exchange: Boeing and GE Aerospace provided immediate access to proprietary telemetry data, including Aircraft Health Monitoring System (AHMS) and logs from the 787’s integrated systems, which were transmitted in real-time to Boeing’s Seattle headquarters prior to the crash. This data is being correlated with FDR and CVR findings to reconstruct system performance. The U.S. NTSB provided software tools for data analysis, while the UK AAIB assisted with expertise in composite material failure.

Emergency Response: The Indian Ministry of External Affairs (MEA) coordinated with embassies in London, Lisbon, and Ottawa to facilitate the identification and repatriation of the remains of British, Portuguese, and Canadian victims. Consular support was extended to affected families, with a dedicated helpline established on June 13, 2025. International investigators were granted visas within 24 hours, ensuring compliance with ICAO’s collaborative investigation protocols.

12. INTERIM CONCLUSIONS AND RECOMMENDATIONS

Probable Cause (Tentative): The leading hypothesis is a combination of incorrect flap or gear configuration (e.g., insufficient flap extension or failure to depressurize retract gear), leading to reduced lift and a low-altitude stall. This could stem from pilot error, such as misinterpreting checklist items under time pressure, or a mechanical failure, such as a flap actuator or hydraulic system malfunction. Secondary factors, including possible pitch trim anomalies or sensor faults, may have exacerbated the situation, overwhelming the crew’s ability to recover.

Safety Measures Proposed: Introduce redundant pre-take-off verification protocols, including automated alerts for flap and gear settings, to prevent configuration errors.

Revised DGCA SOPs: Update standard operating procedures for Boeing 787 operators, emphasizing low-altitude emergency response and stall recovery techniques.

Enhanced Training: Mandate simulator-based low-altitude stall and configuration error scenarios for all 787 pilots, alongside updated CRM training to improve crew coordination.

Urban Zoning Enforcement: Strengthen regulations to restrict high-density developments within 5 km of airport flight paths, with immediate audits of existing violations.

Strengthening Airport Fire Service: Establish dedicated AFS oversight posts within the DGCA and AAIB to enhance fire safety standards. Implement ICAO’s Task Recourses Analysis to Optimize Manpower, Recruitment and upgrade Airport Fire Chief Post at Station Level, Direct Reporting Channel, ensuring adequate staffing and specialized training. Equip AFS with advanced fire-resistant gear. Empower Airport Fire Chiefs to engage media directly during accidents, providing accurate updates to counter misinformation and build public trust. Conduct regular inter-agency drills with local fire services to improve urban crash response.