()- A voice recorder from the cockpit of the Air India flight that crashed last month indicates that the pilot may have shut off the fuel supply to the aircraft’s engines, according to an individual who has been informed about initial findings by U.S. authorities.
This is the timeline of events — second-by-second — on June 12, according to the initial investigative report published by Indian authorities on July 12:
05:47 GMT (11:17 a.m. IST) – The Air India Dreamliner VT-ANB arrived in Ahmedabad from New Delhi under flight number AI423.
07:48:38 GMT – The plane was seen leaving Bay 34 at the airfield.
07:55:15 GMT – The plane asked for permission to move along the ground, which was approved by air traffic controllers; one minute later, the aircraft moved from the parking area to Runway 23 using Taxiway R4, then reversed direction and took position for departure.
08:02:03 GMT - The plane was moved from ground control to tower supervision.
08:07:33 GMT – Permission for takeoff granted.
08:07:37 GMT - The plane began moving along the runway.
08:08:39 GMT – The plane took flight. "The aircraft's air/ground sensors switched to airborne status, aligning with takeoff," the document stated.
08:08:42 GMT – The aircraft achieved a maximum airspeed of 180 knots. "Right after this, the Fuel Cut-off switches for Engine 1 and Engine 2 moved sequentially from the RUN setting to the CUTOFF position, with an interval of 01 second between them."
Engine N1 and N2 started to drop from their takeoff levels when the fuel flow to the engines was interrupted.
In the cockpit audio transmission, one pilot can be heard questioning the other about why he cut off.
The second pilot stated that he had not done that.
The video recorded at the airport revealed that the Ram Air Turbine (RAT) was activated right after takeoff during the early ascent phase.
The plane began descending below the required height prior to passing over the airport boundary fence." "The airplane started losing elevation before reaching the airport’s outer barrier." "Before going past the airport's perimeter wall, the aircraft began to drop in altitude." "The flight commenced an descent as it approached the airport's surrounding structure." "As the aircraft neared the airport's exterior wall, it started to lower in height.
08:08:47 GMT – The readings for both engines dropped beneath the minimum idle speed, prompting the RAT hydraulic pump to start providing hydraulic pressure.
08:08:52 GMT – The fuel shutoff switch for Engine 1 changed from CUTOFF to RUN.
08:08:56 GMT – The fuel shutoff switch for Engine 2 changes from CUTOFF to RUN.
If the fuel control switches are shifted from CUTOFF to RUN during flight, the aircraft's full authority digital electronic control (FADEC) system for each engine will autonomously handle an ignition and fuel supply process to restore power.
The primary engine's rate of slowdown ceased, then changed direction and began moving toward restoration. The second engine managed to reignite but failed to halt the decrease in core velocity, continuously adding more fuel to boost core speed and facilitate recovery.
08:09:05 GMT – A pilot sent out "MAYDAY MAYDAY MAYDAY."
08:09:11 UTC – Recording of data has ceased.
08:14:44 GMT – The crash fire truck departed from the airport area to carry out rescue and firefighting operations.
(Produced by Aditya Kalra; Edited by Jamie Freed)