Mint Explainer | What really went haywire at IndiGo?

Subscribe to enjoy similar stories. NEW DELHI : With hundreds of flight cancellations and delays affecting thousands of fliers since Tuesday, IndiGo—India’s largest budget carrier by market capitalization—is grappling with one of its most severe operational disruptions, prompting a probe by the Directorate General of Civil Aviation (DGCA). Crew shortages due to new duty-time rules, technical breakdowns at key airports, and heavy winter congestion have precipitated the crisis, according to the airline.

Mint explains why IndiGo has been hit the hardest. India's second and final phase of Flight Duty Time Limitations (FDTL), designed to reduce pilot fatigue and improve safety, took effect on 1 November, requiring overhauls to duty schedules, night-landing plans, and weekly rest charts. For instance, pilots’ weekly rest period has been increased from 36 hours to 48 hours.

Night duty hours have been redefined as the period between 0000 and 0600 hours—an extension of one hour—and the permitted number of landings during this window has been reduced from six to two. Additionally, pilots can now be rostered for no more than two consecutive night duties. This means airlines need more pilots and a mandatory reset of their duty rosters, said captain Shakti Lumba, an aviation expert and a former IndiGo employee.

The revision of the FDTL norms followed a DGCA audit that found many airlines were struggling with pilot fatigue—physical and mental exhaustion caused by factors such as sleep deprivation, long hours, irregular schedules, and circadian-rhythm disruptions from time-zone changes. In aviation, this is a critical concern because it can affect flight safety, operational efficiency, productivity, and pilots’ health. The civil