Regulations & Safety
Air India Flight 171 Crash: Engine Failure Analysis & Safety Implications
Preliminary findings reveal accidental engine shutdowns caused 2025 Ahmedabad Boeing 787 crash, prompting cockpit design and training reviews.
Introduction
On June 12, 2025, Air India Flight 171, a Boeing 787-8 Dreamliner, crashed shortly after takeoff from Ahmedabad Airport, resulting in 260 fatalities, including 19 on the ground. The tragic event marked the first fatal accident involving the Boeing 787 since its commercial debut in 2011 and became one of the deadliest aviation disasters in Indian history. The Aircraft Accident Investigation Bureau (AAIB) of India released its preliminary report on July 11, 2025, shedding light on the sequence of events that led to the crash.
The preliminary findings suggest that both engines lost thrust due to the unintended activation of fuel cutoff switches, leading to a dual-engine failure at a critically low altitude. Despite the pilots’ attempts to recover the engines, only one showed signs of partial recovery before the aircraft impacted the ground. This article analyzes the AAIB’s preliminary report, the technical aspects of the aircraft systems involved, and the broader implications for aviation safety and regulatory oversight.
The AAIB and the Context of the Crash
The Aircraft Accident Investigation Bureau (AAIB) operates under India’s Ministry of Civil Aviation and is responsible for investigating civil aircraft accidents and serious incidents. Established in 2012 to comply with ICAO standards, the AAIB functions independently of regulatory bodies like the Directorate General of Civil Aviation (DGCA). Its mandate includes identifying safety deficiencies and recommending preventive measures without assigning blame.
Flight AI171 was a scheduled international service from Ahmedabad to London Gatwick. The aircraft involved was a Boeing 787-8 Dreamliner, powered by two General Electric GEnx-1B engines. At the time of the crash, the aircraft had 230 passengers and 12 crew on board. The flight departed at 13:38 IST and crashed less than two minutes later, at 13:39 IST, approximately 1.5 kilometers from the runway.
The crash site was a densely populated area, resulting in significant ground casualties. The impact and subsequent fire destroyed much of the aircraft, complicating the recovery and analysis of flight data. However, both Enhanced Airborne Flight Recorders (EAFRs) were recovered and provided critical information for the preliminary investigation.
AAIB Preliminary Findings
The AAIB’s preliminary report outlines a sequence of events beginning with the aircraft reaching 180 knots indicated airspeed shortly after takeoff. At this moment, both engine fuel cutoff switches transitioned from RUN to CUTOFF within a second of each other. This action led to an immediate loss of engine thrust, with both engines’ N1 and N2 speeds dropping below idle thresholds.
According to the cockpit voice recorder, one pilot questioned the other about the cutoff, to which the response was a denial of initiating the action. Within seconds, the crew attempted to restart the engines. Engine 1 showed signs of recovery, while Engine 2 failed to stabilize despite multiple relight attempts. A mayday call was made at 08:09:05 UTC, and the crash occurred at 08:09:11 UTC, just 32 seconds after the engine shutdown.
The report also confirms that the flap settings were appropriate for takeoff and that the landing gear was still down, ruling out configuration errors. The thrust levers were found in the idle position post-crash, but data indicated they remained in the forward position until impact, suggesting thermal damage altered their final positions.
“Why did you cutoff?”, a pilot’s question captured on the CVR, highlighting cockpit confusion during the critical seconds before the crash.
Technical Analysis: Engine Systems and Human Factors
The Boeing 787-8 is equipped with FADEC (Full Authority Digital Engine Control) systems, which manage engine performance and relight sequences automatically. FADEC systems monitor and adjust engine parameters in real-time, reducing pilot workload and improving efficiency. However, they also introduce complexity and potential vulnerabilities.
In the case of AI171, the FADEC systems initiated relight sequences after the fuel control switches were returned to RUN. Engine 1 responded positively, but Engine 2 could not recover its core speed. The relight attempt occurred at an altitude of less than 400 feet, a scenario outside the typical operational envelope for successful engine restart.
Human factors also play a critical role in this incident. The placement of fuel cutoff switches on the overhead panel and their lack of protective guards may contribute to inadvertent activation. Additionally, Air India’s training protocols reportedly do not include simulator scenarios for dual-engine failure at low altitude, as such events are considered statistically improbable and unrecoverable.
Design and Training Considerations
The design of cockpit controls, including the accessibility and safeguarding of critical switches, is under renewed scrutiny. Unlike some Airbus aircraft, the Boeing 787 does not feature guarded fuel cutoff switches, increasing the risk of accidental activation. This design choice may prompt future modifications depending on the investigation’s final findings.
Training standards are also being evaluated. Dual-engine failure at low altitude is not typically included in simulator training due to its extreme rarity. However, this incident suggests that even low-probability events can have catastrophic consequences, and training protocols may need to evolve accordingly.
Experts have emphasized the importance of scenario-based training that prepares pilots for high-stress, low-altitude emergencies. The inability to recover Engine 2 and the evident confusion in the cockpit underscore the challenges of managing such a situation without prior rehearsal or procedural guidance.
Broader Implications for Aviation Safety
The crash of AI171 has far-reaching implications for aircraft design, pilot training, and regulatory oversight. Although the AAIB has not issued immediate safety recommendations, the findings have already prompted internal reviews by Boeing, General Electric, and the DGCA.
One area of concern is the standardization of cockpit interfaces and the need for physical safeguards on critical switches. If the final report confirms that the switches were accidentally activated, design changes may be mandated across the global 787 fleet. Over 1,000 Boeing 787s are currently in service worldwide, making any potential retrofit a significant undertaking.
Regulatory bodies may also revise training requirements to include rare but high-risk scenarios. The ICAO and national aviation authorities could consider mandating simulator sessions for dual-engine failure at low altitudes, especially for new aircraft types with advanced automation systems.
“This tragedy underscores the need for enhanced safeguards against inadvertent cockpit actions and revised training for low-altitude emergencies.”
Conclusion
The preliminary report into the crash of Air India Flight 171 identifies a probable sequence of events involving the inadvertent shutdown of both engines shortly after takeoff. Despite prompt recovery efforts by the flight crew, the aircraft could not regain thrust in time to avoid impact. The incident raises critical questions about cockpit ergonomics, FADEC system behavior, and pilot preparedness for rare emergencies.
As the AAIB continues its investigation, the aviation community is watching closely for recommendations that could influence future aircraft design and operational protocols. The final report is expected to provide a comprehensive analysis, including potential design changes, training reforms, and safety directives aimed at preventing similar tragedies in the future.
FAQ
What caused the engines to shut down on AI171?
The preliminary report indicates that both engine fuel cutoff switches were inadvertently moved from RUN to CUTOFF, resulting in a loss of thrust.
Did the pilots try to restart the engines?
Yes, the pilots attempted to restart both engines. Engine 1 showed signs of recovery, but Engine 2 failed to stabilize before the crash.
Were there any technical faults with the aircraft?
The AAIB found no evidence of pre-existing technical faults or structural failures. Both engines had recently undergone maintenance.
What is FADEC and how did it affect the outcome?
FADEC (Full Authority Digital Engine Control) is an automated system that manages engine performance. It initiated relight sequences, but the low altitude limited their effectiveness.
Will this lead to changes in aircraft design or training?
While no official recommendations have been made yet, the incident may prompt design reviews of cockpit controls and updates to pilot training protocols.
Sources
Photo Credit: AAIB