Whether or why both engines would have simultaneously lost power remains unknown, but investigators will seek additional clues from the two flight recorders, from which data has been extracted and is being analysed.
The investigation is exploring a wide range of scenarios, though a closer focus is on technical issues, the people said.
Pilots who reviewed the footage have noted that the landing gear was already partially tilted forward, suggesting the cockpit crew had initiated the wheel retraction sequence.
At the same time, the landing gear doors had not opened, which pilots say might mean that the aircraft experienced a loss of power or a hydraulic failure, again pointing to possible issues with the engines that provide the aircraft’s electricity.
The engines of modern aircraft are computer-controlled using a system called Full Authority Digital Engine Control, or FADEC, which helps pilots control an aircraft’s power and makes sure the engines are used efficiently and not outside their operating limits.
An emergency turbine, called the RAT, which deploys from the back of the aircraft in the case of electrical failure, was activated before the plane crashed, according to previous findings.
That fan helps provide the aircraft with vital power, though it’s far too small to generate any lift.
Fifteen seconds
Analysis of the wreckage suggests the wing flaps and slats, which help an aircraft increase lift during takeoff, were extended correctly.
The crash ranks as the worst accident in Indian civil aviation in several decades, and it’s the first time that a Boeing 787 Dreamliner has been lost to an accident.
The pilots, who died in the crash, sent out a mayday signal shortly after take-off. There were only about 15 seconds between the distress call and impact, two people familiar with the investigation said.
Teams from Boeing and the US National Transportation Safety Board are supporting the investigation on the ground.
It’s unknown when authorities will give an update on the flight recorder data, which typically provides a comprehensive analysis of an aircraft’s settings and performance metrics as well as conversations in the cockpit.
