New Delhi, July 23 -- Air India said on Tuesday it has completed inspections of fuel control switches on all its Boeing 787 and 737 aircraft, in line with directives from the Directorate General of Civil Aviation. The inspections come amid intense scrutiny of fuel control switches following the Air India Flight 171 crash that killed 260 people in June. The preliminary probe report by the Aircraft Accident Investigation Bureau (AAIB) found the aircraft's fuel switches were set from "run" to "cutoff" position during take-off, starving the engines in what is likely the direct cause of the crash. How the switches were set to that position - whether deliberately (and by whom) or due to some other factors - is now at the centre of the investigation. Fuel control switches are designed with multiple safety mechanisms, including spring-loaded locking features and metal guards to prevent accidental movement. "Air India has completed precautionary inspections on the locking mechanism of Fuel Control Switch on all Boeing 787 and Boeing 737 aircraft in its fleet. In the inspections, no issues were found with the said locking mechanism," an Air India spokesperson said. A 2018 US Federal Aviation Administration safety bulletin, also referenced by the AAIB, warned of potential disengagement of the locking mechanism on several Boeing aircraft models, including the 787. This technical vulnerability has gained renewed attention, thought the 2018 communication was not mandatorily meant for corrective action at the time. The airline started voluntary inspections on July 12 and completed them within the time limit set by the DGCA. Boeing 737 aircraft are part of Air India Express's fleet, the airline's low-cost subsidiary. The DGCA had directed the inspection after the AAIB released its preliminary report. The civil aviation regulator mandated all Indian airlines to inspect fuel switch controls of specified aircraft models by July 21, referring to the 2018 FAA safety notice. "Strict adherence to the timeline is essential to ensure continued airworthiness and safety of operations," the DGCA instructed. Etihad Airways, one of the United Arab Emirates' two flag carriers, instructed its engineering team to inspect the locking mechanism of the fuel control switches on its B787 aircraft. It also advised caution during operations. In its safety circular- Etihad instructed its team to fully inspect the locking feature for "proper engagement."...