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The Aircraft Accident Investigation Bureau has roped in human factors specialists to assist with its ongoing investigation into the AI-171 Ahmedabad crash, the government told Parliament on Thursday.“B787 type-rated experienced pilots, type-rated engineers, aviation medicine specialists, human factor specialists, and flight recorder specialists have been taken on board as subject matter experts to assist the investigation," Minister of State for Civil Aviation Murlidhar Mohol said.

This move follows multiple reports in Western media blaming the senior pilot for the fatal crash.

The Emergency Locator Transmitter (ELT), a critical post-crash distress beacon, was never activated, as per the AAIB report. It was recovered intact in the wreckage, yet it was silent.A CCS/core network failure would not by itself stop the transmission from an ELT’s automatic g-switch — which is a gravity (g) switch with a sensor that detects sudden changes in acceleration (g-forces) that typically occur during a crash.

That is, unless the ELT’s antenna and wiring had melted in a fire — and one possible pointer to that is a Category A fault logged on AI 171’s Nitrogen Generation System (NGS), a safety feature Boeing added to prevent fuel tank fires in the aftermath of the Trans World Airlines Flight 800’s midair explosion due to a central fuel tank ignition in 1996.

The NGS works by continuously flooding the tail fuel tank’s ullage (the empty space above the fuel) with nitrogen-rich air, displacing oxygen and thereby preventing the build-up of flammable vapours.

If the NGS were not functioning, the oxygen levels around the aft-fuel tank bay may have been dangerously high. In that scenario, even a small spark—possibly from an electric arc or surge—could ignite a localised fuel-air vapour fire. That would have burnt the wiring and antenna of the ELT and wiring, connectors, and housing of tail-section black box or the aft Enhanced Airborne Flight Recorder (EAFR). And this scenario would be in line with the AAIB report, which shows the tail section was more structurally intact compared to the nose.