Ahmedabad plane crash: TCM of the crashed Dreamliner was changed twice, fuel control switch is also a part of it

New Delhi. Air India had replaced the Throttle Control Module (TCM) of the Boeing 787-8 Dreamliner aircraft that crashed in Ahmedabad in 2019 twice in the last 6 years following instructions from Boeing. TCM includes fuel control switches. The ongoing investigation into this fatal accident has revealed that soon after Air India’s Boeing Dreamliner aircraft VT-ANB took off from Ahmedabad airport, the fuel control switches of both the engines went from ‘run’ to ‘cutoff’ position in an interval of one second, due to which confusion arose in the cockpit of Air India flight number 171.

The report released by the Aircraft Accident Investigation Bureau (AIIB) on Saturday morning revealed that the senior pilot had asked his junior – ‘Why did you turn off the fuel control switch?’. In response to this, the junior pilot had said, ‘I did not turn off the switch’. The height of the aircraft decreased immediately due to the fuel control switch moving from ‘run’ to ‘cutoff’ position. The plane crashed on a building of BJ Medical College in Meghaninagar area of ​​Ahmedabad soon after take off. 260 people were killed in this accident. Out of the 242 people on board the plane, including the crew, only 1 person survived. 19 students of the medical college also became victims of this accident.

Air India had changed the TCM in 2019 and 2023
In the AAIB preliminary investigation report, there is a mention of changing the TCM twice in 2019 and 2023. The report also said that the replacement of the TCM had nothing to do with the fuel control switch. The source told PTI that Boeing had issued a revised maintenance plan document (MPD) to all operators of the Dreamliner in 2019. According to this, operators were suggested to replace the TCM after completing 24,000 hours of flight. After the 2019 MPD was issued by Boeing, Air India replaced the TCM in the crashed aircraft twice – in 2019 and 2023. PTI tried to get a response from Air India in this regard, but it has not yet responded to the questions.

In response to questions sent to Boeing, a company spokesperson said on Sunday that the company would continue to assist in the investigation. The AAIB said in its report on Saturday that at this stage of the investigation, ‘no action has been recommended against the B787-8 or GE GEnx-1B engine operators and manufacturers.’ Air India’s Dreamliner VT-ANB, which crashed in Ahmedabad on June 12, was fitted with GE GEnx-1B engines. The US Federal Aviation Administration (FAA) had on December 17, 2018, flagged the locking features of the fuel control switch in Boeing aircraft as a potential problem.

US regulator had warned on fuel switch in 2018
Air India told the AAIB team probing the Ahmedabad plane crash that it did not carry out the inspections suggested by the FAA as it was not mandatory. The report also said that all the necessary inspections were currently carried out in the crashed aircraft and it also had a valid airworthiness certificate. The report said, ‘However, the reason for changing the TMC was not related to the fuel control switch. No problem related to the fuel control switch was reported in the crashed VT-ANB since 2023.’ According to the report, after the fuel control switch went from ‘run’ to ‘cut-off mode’ in Air India flight number 171, the fuel control switches of both the engines of the aircraft were turned on again, but the aircraft could not gain sufficient speed and altitude and crashed into a building of BJ Medical College in Ahmedabad.