Questions mount over gaps, error in ‘opaque’ AI prelim crash report
Times of India | 14 July 2025
Kolkata: Veteran pilots from various airlines who reviewed the preliminary AI 171 crash report have questioned whether a software glitch or mechanical failure — which could cause fuel valves in a Boeing 787 Dreamliner to switch off — was ruled out before it was published.
An experienced pilot said it was curious that the report did not even mention this possibility. "On the B 787, fuel shut-off valves are controlled via remote data units (RDUs). While the left and right engines have independent RDUs, power is supplied via remote power distribution units (RDPUs), which are software-based electrical substations. Since RCDs and RDPUs are networked, a common software error or network fault could potentially impact both engines," the pilot said.
Another industry veteran pointed out that valve closure due to power interruption or software glitches was flagged during the initial rollout of B 787. Pilots have also flagged issues in the report like incorrect and incomplete information, which has sparked speculation about pilot culpability.
While appreciating the move to publish a report on the primary findings, pilots pointed out that even basic information, like the flying hours of Captain Sumeet Sabharwal mentioned, was erroneous. Sabharwal's airline transport pilot licence was issued on May 14, 2021. With DGCA stipulating a maximum of 1,000 flying hours a year, he could have 4,000 hours under his belt as pilot in charge by May 2025. The report, however, logs this at 8,260 hours.
Pilots also allege that the report is deliberately opaque on several issues and uses words and phrases selectively to not only hint at human error but insinuate ill intent behind the accident. They make three arguments to substantiate this.
First, just one brief exchange between the captain and the first officer is presented in the report in indirect speech, instead of releasing the entire transcript of the interaction in the 21 minutes between when the flight departed the parking bay and when it crashed. The most crucial section is the 1 minute 22 seconds between ATC takeoff clearance and the Mayday call.
"Why is the transcript of the conversation from the cockpit voice recorder not given in its entirety so that the context can be understood? The report states: ‘In the cockpit, in the cockpit voice recording, one of the pilots is heard asking the other why did he cut off. The other pilot responded that he did not do so'," a pilot said.
Pilots also pointed to the use of the phrase "transition" of fuel switches instead of attributing it to human action, and said it was an insinuation that the men in the cockpit were responsible for the catastrophic accident.
A captain said: "In an extremely challenging and unprecedented situation, these men were trying their best to achieve the impossible. They were too close to the surface for recovery, which they did attempt per the checklist, which is a testament to their sound and calm minds.
"He said that in the case of dual engine loss, the full authority digital engine control (FADEC) that optimises engine performance is reset using the following procedure: start switches on; shift thrust lever to idle; shift fuel switches from run to cut off to run. "This is exactly what the pilots appear to have done and managed to get one engine to start revving up but rammed into a building before the engine could spool up," he said.
Airline Pilots Association of India president Captain Sam Thomas said the tone and direction of the investigation suggested a bias towards pilot error. "ALPA-I categorically rejects this presumption and insists on a fair, evidence-based inquiry," he said.