Fuel control switches were replaced twice in 6 years in Air India crashed plane

TCM includes substance power switches, which person travel to absorption successful the ongoing probe into the fatal clang arsenic these switches were chopped disconnected instantly aft takeoff of the ill-fated London-bound Dreamliner VT-ANB that crashed successful Ahmedabad connected June 12

Remains of the Air India level that crashed successful Ahmedabad. PTI Photo

Air India replaced the Throttle Control Module (TCM) of the crashed Boeing 787-8 level doubly successful the past six years pursuing a directive from Boeing successful 2019, sources said connected Sunday.

TCM includes substance power switches, which person travel to absorption successful the ongoing probe into the fatal clang arsenic these switches were chopped disconnected instantly aft takeoff of the ill-fated London-bound Dreamliner VT-ANB that crashed successful Ahmedabad connected June 12.

The replacement of the TCM doubly -- successful 2019 and 2023 -- was mentioned successful the Aircraft Accident Investigation Bureau's (AAIB) preliminary probe study into the clang that was released connected Saturday. It besides said the TCM replacement was not linked to the substance power switches.

The root told PTI that a revised Maintenance Planning Document (MPD) was issued by Boeing for each the operators of the Dreamliners successful 2019.

As per the MPD, the operators person to alteration the TCM, which includes the substance power switches, each 24,000 formation hours, the sources said.

Since 2019, erstwhile the MPD was issued, the root said Air India changed the TCM successful the ill-fated craft doubly -- successful 2019 and 2023.

Queries sent to Air India remained unanswered.

Specific details astir the MPD could not beryllium instantly ascertained.

In effect to questions sent to Boeing, a institution spokesperson connected Sunday referred to its connection issued connected Saturday saying it volition proceed to enactment the probe and Air India.

"We volition defer to the AAIB to supply accusation astir AI171, successful adherence with the UN International Civil Aviation Organisation protocol known arsenic Annex 13," the spokesperson said successful the emailed statement.

AAIB, successful its study connected Saturday, said that astatine this signifier of investigation, "there are nary recommended actions to B787-8 and/or GE GEnx-1B motor operators and manufacturers".

Air India's Dreamliner VT-ANB, which crashed connected June 12, was powered by GEnx-1B engines.

According to the report, FAA issued Special Airworthiness Information Bulletin connected December 17, 2018, regarding the imaginable disengagement of the substance power control locking feature.

"This SAIB was issued based connected reports from operators of Model 737 airplanes that the substance power switches were installed with the locking diagnostic disengaged. The airworthiness interest was not considered an unsafe information that would warrant airworthiness directive by the FAA," it said.

AAIB besides said the substance power control design, including the locking feature, is akin connected assorted Boeing airplane models including portion fig 4TL837-3D, which is fitted successful B787-8 craft VT-ANB.

"As per the accusation from Air India, the suggested inspections were not carried retired arsenic the SAIB was advisory and not mandatory. The scrutiny of attraction records revealed that the throttle power module was replaced connected VT-ANB successful 2019 and 2023.

"However, the crushed for the replacement was not linked to the substance power switch. There has been nary defect reported pertaining to the substance power control since 2023 connected VT-ANB," the study said.

After being successful cut-off mode, the substance power switches of the aircraft's 2 engines were turned connected aboriginal but the London-bound craft could not get capable thrust and altitude earlier it crashed into a gathering successful Ahmedabad sidesplitting 260 people.