The Aircraft Accident Investigation Bureau (AAIB) preliminary report on the Air India AI171 crash on June 12 has made aviation experts call for the release of the cockpit voice recording (CVR) and flight data recorder (FDR) to clarify the reasons behind the engines shutting down after fuel supply was cut off.
Questions are also being raised about the Federal Aviation Administration (FAA) Special Airworthiness Information Bulletin (SAIB) No. NM-18-33, issued in December 2018, which flagged the potential disengagement of the fuel control switch locking feature in Boeing aircraft, including the B787-8 fitted with similar part numbers.
The AAIB report also mentions the FAA Bulletin, adding that “As per the information from Air India, the suggested inspections were not carried out as the SAIB was advisory and not mandatory.”
“The CCTV images provided in the AAIB report are not timestamped, and they have not made public the CVR and FDR to ascertain what happened. It is a point of suspicion,” said Amit Singh, aviation safety expert and founder of the Safety Matters Foundation.
He further says that the FAA bulletin was advisory, but Air India did not check the potential disengagement of the fuel control switch locking feature in Boeing aircraft, citing that it was not mandatory.
“The advisory means that the airline doesn’t have to rush to conduct the checks but does it over time. It is like a police advisory not to visit a prohibited area, but if you do so and something happens, it’s at your own risk,” Singh tells Business Today.
The AAIB report on the FAA advisory noted that scrutiny of maintenance records revealed that the throttle control module was replaced on VT-ANB in 2019 and 2023. However, the reason for the replacement was not linked to the fuel control switch. There has been no defect reported pertaining to the fuel control switch since 2023 on VT-ANB.
Sanjay Lazar, an aviation expert and CEO of Avialaz Consultants, says the report raises more questions than it answers. “It is regrettable that the entire CVR transcript was not released by the AAIB. Without a thorough investigation being completed, how could the AAIB have issued a line that no recommendations for Boeing or GE were necessary, literally absolving them? I am shocked that the AAIB has literally let Boeing and GE get out of jail free.”
Calling for a deeper investigation before the final statement of the report was issued by the AAIB, given the FAA advisory, he said:
“I think it’s unfortunate that questions have been raised about the alleged actions of the pilot, especially since the CVR transcript was never made public and just one line of reference was made,” Lazar told BT.
Industry veteran Captain Shakti Lumba, who retired as IndiGo Vice President, emphasised the need for a judicial court of inquiry. “Going by Indian aircraft accident data over the last 70 years (which DGCA maintains), in all accidents to commercial aircraft involving such a large number of fatalities, the government has always formed a court of enquiry.”
