IndiGo is cancelling large numbers of flights mainly because of a crew shortage triggered by new pilot “fatigue” rules that limit how long pilots and cabin crew can work before they must rest. This has snowballed into a large operational disruption across many Indian airports, especially in the winter schedule.

Main reasons

• India’s aviation regulator recently tightened Flight Duty Time Limitation (FDTL) rules, which require longer rest periods and stricter limits on night and consecutive duties for pilots and crew. IndiGo did not adjust its schedules and staffing quickly enough, so many pilots hit their duty limits and could not legally operate flights.

• Because IndiGo runs a very dense network (over 2,000 flights a day), even a modest shortfall in available crew led to hundreds of cancellations and widespread delays when things went wrong. Once delays pushed flights past certain times, more crews went out of permitted hours, causing cascading cancellations.

Other contributing factors

• The airline and government have also mentioned minor technology glitches, winter timetable changes, bad weather and congestion in Indian airspace as secondary reasons that worsened the disruption.

• Pilot groups and aviation experts have criticised IndiGo’s planning, pointing to hiring freezes, tight staffing and poor roster preparation despite having advance notice of the new rules, which left the airline less resilient when the regulations took full effect.