AAIB Submits Preliminary Report On Air India 171 Plane Crash To Civil Aviation Ministry

The Aircraft Accident Investigation Bureau (AAIB) has submitted its preliminary report on the Air India Flight AI-171 crash in Ahmedabad to the Ministry of Civil Aviation and other relevant authorities. This report is based on initial findings from the investigation into the tragic incident that resulted in over 250 fatalities.

Before this crash, AAIB often sent black boxes from damaged aircraft to overseas centres for decoding. Countries like the UK, USA, France, Italy, Canada, and Russia were frequently used. Indian labs lacked the necessary equipment for serious aviation accident data retrieval. However, this has changed with the establishment of a fully equipped AAIB Lab in Delhi.

Black Box Retrieval and Analysis

The Crash Protection Module (CPM) from the front black box was safely retrieved. On June 25, 2025, data from its memory module was successfully accessed and downloaded at the AAIB Lab. An identical black box known as a "golden chassis" was used to verify data recovery accuracy.

One black box was found on a building rooftop at the crash site on June 13. The other was recovered from debris on June 16. The investigation is led by AAIB officials with technical members from various organisations including the Indian Air Force and Hindustan Aeronautics Limited (HAL).

International Collaboration in Investigation

The National Transportation Safety Board (NTSB) from the United States is also involved due to their role as the official investigative agency of the aircraft's design and manufacture country. The Director General of AAIB heads this probe.

An aviation medicine expert and an Air Traffic Control officer are part of the team. NTSB representatives are currently stationed in Delhi, working closely with Indian authorities at the AAIB Lab. Boeing and GE officials are also present to assist technically.

Advancements in Black Box Decoding

Previously, black box decoding for crashes like Charkhi Dadri in 1996 was done abroad. In that case, IAC decoded it in Moscow while CVR analysis occurred in Farnborough, UK. Similarly, after the Mangalore crash in 2010, recorders were repaired and decoded by NTSB in America.

In more recent incidents like Delhi's 2015 crash, Canada's Transportation Safety Board handled decoding at their engineering lab. For Kozhikode's 2020 crash, DGCA's flight recorder facility downloaded CVR and FDR data but needed NTSB assistance for processing.

The new AAIB Lab can now decode Cockpit Voice Recorders (CVR) and Flight Data Recorders (FDR) domestically without relying on foreign facilities.

Engine Fuel Cutoff as Central Factor?

Meanwhile, The Air Current, a subscription-based aviation news service, on July 8, reported that both engine fuel control switches were moved from 'run' to "cutoff" within seconds of each other, immediately after takeoff.

This deliberate action cut fuel to both engines, causing a total loss of thrust and resulting in the crash, the report said, citing multiple people with knowledge of the investigation.