Since the Tata takeover, India’s Directorate General of Civil Aviation has repeatedly fined Air India over safety and other regulatory violations, including an Rs8mn ($95,000) penalty last year for exceeding flight duty time limits. At home, it is competing in a near-duopoly with IndiGo, which has been boosting its international long-haul routes.

Air India's deadly plane crash that killed at least 270 people has triggered a wave of speculation about what led to the world's worst aviation disaster in a decade, but authorities are slowly narrowing down areas of investigation.