India's pilot fatigue rules explained: Why FDTL is disrupting flight schedules

India's tighter FDTL pilot fatigue norms have triggered cancellations and delays, exposing crew shortages, roster stress and a fresh debate over safety, planning and preparedness

India’s aviation sector has hit turbulence this week as the first full month of India’s tightened Flight Duty Time Limitations (FDTL) collided head-on with winter schedules, a pilot crunch and a burst of technical snags. More than 300 IndiGo flights have reportedly been cancelled in just two days, while on-time performance plunged to 35 per cent, leading to airport terminals from Mumbai to Bengaluru witnessing growing queues of stranded and frustrated passengers. What began as a regulatory push to curb pilot fatigue has quickly escalated into a national conversation about preparedness, scheduling discipline and the fragility of India’s busiest airline at a moment when demand is soaring.

 

What are FDTL norms?

 

The FDTL rules determine how long pilots can be on duty, how many hours they can fly, how many night landings they may perform, and the minimum rest they must receive. The Directorate General of Civil Aviation (DGCA) revised these limits in January 2024 after reviewing fatigue reports and global standards. The new norms, implemented in two phases, lengthen weekly rest, extend the definition of night, and place stricter caps on night operations with the aim of reducing fatigue-related safety risks.

 

Key changes now in force include:

 

• 48 consecutive hours of weekly rest for pilots

 

• Night defined as 00:00–06:00 instead of the earlier 00:00–05:00

 

• A limit of two night landings instead of six

 

• No more than two consecutive night duties

 

• Mandatory roster adjustments and quarterly fatigue reporting

 

Why is FDTL back in the news?

 

The revised DGCA FDTL rules were notified with immediate effect on May 31 last year, with airlines initially required to comply by June 1, 2024, but their implementation was deferred to a phased roll-out starting July 1, 2025 and completing by November 1 this year.

 

And the transition has exposed gaps in crew availability across airlines. The most visible impact has been at IndiGo, India’s largest carrier. Over the past two days, the airline has cancelled more than 300 flights and delayed hundreds more, according to aviation industry sources as reported by this newspaper. Operating roughly 2,300 flights a day, this means nearly 7 per cent of its services were cancelled within 48 hours.

 

Official data from the Ministry of Civil Aviation showed IndiGo’s on-time performance fell to 35 per cent on Tuesday (December 2), one of its lowest recorded figures in recent years. The airline later announced “calibrated adjustments” to its schedules over the next two days to stabilise operations.

 

Why do pilot fatigue limits matter for safety?

 

FDTL exists to ensure aviation safety. Global regulators treat fatigue as a significant operational risk, especially on early-morning departures and night landings. By expanding mandatory rest and reducing the intensity of night operations, the DGCA has also aimed to align Indian practice more closely with international norms.

 

However, the trade-off has been operational complexity. Implementing the rules often requires more pilots or revised schedules. Airlines warn that sudden or rigid transitions can affect capacity, drive cancellations and raise costs.

 

Are airlines pressuring DGCA for relaxations?

 

The operational disruptions have led to a debate on the method and effectiveness of the FDTL rules. Some carriers are arguing that the transition period has been challenging and that roster adjustments take time to stabilise.

 

Meanwhile, the Airline Pilots’ Association of India (ALPA) has accused IndiGo of “arm-twisting” the regulator by cancelling flights to push for relaxed norms. ALPA said airlines had “sufficient time” to prepare but began adjusting rosters too late. The union also flagged “slot hoarding”, suggesting that some carriers may have filed ambitious winter schedules to retain airport slots without having the crew strength to operate them reliably.

 

The FDTL rules are meant to make flying safer, but the turbulence now unfolding also reflects the difficulty of transitioning at scale. How quickly airlines stabilise operations, and how firmly the regulator holds the line on fatigue norms, will determine whether this disruption is temporary or a sign of deeper structural strain in Indian aviation.