AVGEEK
AI171’s preliminary report: fuel switches, evidence and unanswered questions
Sanjay Lazar, Devesh Agarwal and Captain Kishore Chinta examine flight-data interpretations, fuel-control switch transitions, cockpit procedures and gaps in the preliminary report, while questioning premature conclusions about the accident.
The conversation
In this special edition of The Indian AvGeek, we have three of India’s leading aviation experts—Sanjay Lazar, Devesh Agarwal, and Captain Kishore Chinta—to dissect the preliminary AI171 crash report. Through a blend of technical insight and human-factors analysis, they chart the accident timeline, examine cockpit ergonomics, and question the selective data release by AAIB.
From the fuel control switch movements in the EAFR data to the haunting cockpit voice exchanges about who “cut off” the engines, our panel explores:
- Initial reactions to the preliminary report - How EAFR switch positions frame the crash sequence - Pilot decision-making and stress at low altitude - Possible motives behind withholding CVR and DFDR transcripts - Technical and aerodynamic reasons for asymmetric engine relight - Implications for cockpit switch-locking designs and walk-around call-outs - Relevance of FAA’s 2018 SAIB NM-18-33 on fuel-switch locks - The curious omission of GE’s GEnx-1B SB 73-0097 R01 from the report - Distinctions between mandatory and advisory safety bulletins - Priorities after RAT deployment: MAYDAY, systems configuration, or flying the profile - Intuitiveness of the 787’s fuel-control layout and best practices to prevent inadvertent cuts - Mechanics of international cooperation among AAIB, NTSB, DGCA, and others - Potential global ripple effects on Boeing 787 operations - Critical evidence and analysis are still needed for a conclusive investigation - How the scope and timeline of the final report will differ from preliminary findings
Captain Kishore Chinta - @Capt_CK Sanjay Lazar - @SJLazars Devesh Agarwal - @BLRaviation Vishal Mehra - @vishal1mehra
Key Takeaways
- The panel examines what the July 2025 AAIB preliminary report does and does not establish about AI171; a preliminary factual account is not a final finding of cause.
- Captain Kishore Chinta distinguishes flight-recorder indications of a system or switch state from direct proof of physical switch movement, and calls for correlated evidence.
- The discussion considers how crews prioritise aircraft control and alerts immediately after take-off, while noting that incomplete public recorder information limits reconstruction.
- The speakers explore possible FADEC relight and engine-response explanations, but none of these possibilities is established as the cause of the accident.
- Devesh Agarwal distinguishes advisory safety notices from legally enforceable airworthiness directives; cited bulletins are investigative questions, not demonstrated causal links.
- Sanjay Lazar strongly criticises the preliminary report's level of detail and transparency; his suspicions of concealment or outside influence remain unsubstantiated opinions.
- All participants agree that additional synchronised evidence and a rigorous investigation are necessary before responsible conclusions can be drawn about responsibility or mechanical failure.
Editorial analysis
What the preliminary report can—and cannot—establish
The most important question in this unusual panel is not who caused the Air India flight AI171 tragedy. It is what the public could legitimately infer from the limited evidence released in a preliminary investigation report. The distinction is essential. The report describes parameters and a sequence of events; it does not constitute a final finding about how or why a switch-state change occurred. Captain Kishore Chinta presses the difference between a recorded electrical or system state and direct observation of a physical movement. Devesh Agarwal subsequently makes a similar argument about the word “transition”: a recorded transition should not automatically be narrated as a person touching a switch. Neither proposition proves a malfunction or rules out human action.
Cockpit workload and recorded system states
The panel also discusses the extraordinary workload facing an airline crew in the seconds after take-off, when immediate priorities are to control the aircraft and identify failures under intense time pressure. Chinta describes the operational distinction between a crew’s manual action and an automatic full-authority digital engine control (FADEC) relight process, while repeatedly noting that critical timing and system evidence was not available to the speakers. Host questions about a possible asymmetrical relight, ram-air turbine deployment and memory items are discussed as technical possibilities, not established reconstruction.
Technical possibilities are not findings
The strongest editorial subject is investigative transparency and public confidence. Lazar argues forcefully that the preliminary report lacked details he would have liked and makes serious allegations about institutional incentives and external influence. Those are his unproved suspicions, not findings adopted by this edition. Agarwal discusses the different force of advisory bulletins and mandatory airworthiness directives. None of the panel’s references to an FAA notice, GE bulletin, past incident or electronic failure constitutes evidence of causation in AI171. The safe conclusion is methodological: evidence must be synchronised, tested against alternative explanations and considered by investigators with access to complete recorder, physical and operational records.
What further evidence must resolve
Subsequent official context: In a statement dated 12 June 2026, India’s AAIB said that its final investigation report had not yet been completed and that analysis of technical, operational, organisational and human factors remained under way. The AAIB’s preliminary report was issued 12 July 2025. This edition neither adopts allegations against either pilot nor endorses a manufacturer/electronics-failure theory. Official statement: https://www.pib.gov.in/newsite/erelcontent.aspx?lang=2®=48&relid=289951.
Questions & answers
What is your initial view of the preliminary report?
He says it contains too little publicly disclosed context and criticises transparency; his more serious claims are his suspicions alone.
What do data-recorded fuel switch changes mean?
A recorded state does not independently prove physical movement, so detailed correlation is required.
What could the pilots do at such low altitude?
The workload and timing were extreme, and the publicly known sequence is insufficient to attribute individual actions.
How relevant are FAA and GE safety notices?
He distinguishes advisory from mandatory action and asks for their relevance to be assessed, without establishing causation.
What additional evidence is necessary?
Examine alternative scenarios, correlate physical evidence with cockpit voice and system data, and progressively eliminate possibilities.
Sources & attribution
Original conversation: The Indian AvGeek — Episode 45. Originally published 13 July 2025.
Historical context: This editorial analysis reports and interprets positions from the original 2025 conversation. Estimates, forecasts, commercial relationships and policy statements must not be mistaken for current conditions or independent verification as of October 2026.
Editorial Q&A: Questions and answers are explanatory editorial paraphrases, not verbatim dialogue.
Accident-investigation caution: The interview discusses the July 2025 preliminary investigation into Air India flight AI171. Its assessments are not an official finding of cause, fault or individual responsibility. Recorded system states must not be equated with proven physical actions. Check subsequent AAIB disclosures before public release.
Guests
Sanjay Lazar
Sanjay Lazar brings a career spanning four decades in aviation, much of it at Air India. His conversations with Vishal Mehra cover airline integration, safety oversight and the industry's institutional history. He also joins the panel examining the preliminary AI171 accident report. These appearances place operational questions alongside the organisational context in which airlines work.
Devesh Agarwal
Devesh Agarwal is the founder of Bangalore Aviation. His appearances range from aircraft maintenance and airline management to a two-part assessment of Indian aviation in 2024. He also contributes to the discussion of the preliminary AI171 accident report. Across the archive, his conversations connect infrastructure, regulation and the operating realities of Indian airlines.
Captain Kishore Chinta
Captain Kishore Chinta brings experience in the Indian Air Force and civil aviation. His first conversation with Vishal Mehra examines the opportunities and constraints facing general aviation in India. He later joins a panel discussing the preliminary AI171 accident report. His appearances give flight operations and the pilot's perspective a place in the wider industry discussion.