India's largest airline IndiGo experienced a severe scheduling crisis beginning December 2, 2025, with nearly 4,500 flights cancelled over the first ten days. The crisis stemmed from IndiGo's failure to adequately prepare for the new Flight Duty Time Limitation (FDTL) rules mandated by the Directorate General of Civil Aviation (DGCA). These rules, announced in June 2024, increased mandatory pilot rest periods and reduced night-time duty hours — but IndiGo delayed implementation, leading to acute crew shortages at the start of December. Cancellations peaked at approximately 1,600 on December 5, severely impacting India's peak wedding travel season. On December 5, DGCA granted IndiGo a temporary exemption from certain night duty rules until February 10, 2026, with reviews every 15 days. However, pilot unions criticised this exemption as compromising flight safety. DGCA subsequently levied a penalty of ₹22.2 crore on IndiGo and issued a warning to its top management. The crisis exposed systemic weaknesses in airline workforce planning, regulatory compliance gaps, and India's civil aviation infrastructure's vulnerability during peak demand periods. The Indian aviation sector carries over 160 million passengers annually, and IndiGo holds approximately 60% domestic market share.