New Delhi: IndiGo’s widespread flight cancellations and delays across India over the past several days were primarily triggered by poor crew rostering under new Flight Duty Time Limitations (FDTL) and a technical glitch in its crew-rostering and scheduling software, aviation officials told HT on Thursday. The disruptions, which began on December 3, have affected hundreds of flights daily and left thousands of passengers stranded at airports nationwide.

Officials noted that the airline also faced technical issues in its baggage handling systems, particularly at Delhi’s Terminal 3 and Terminal 1. While the software-related glitches were eventually resolved, cascading delays in baggage delivery continued, compounding passengers’ hardships and straining airport infrastructure. The combined effect of crew shortages, poor scheduling, and baggage system problems created an unprecedented operational challenge for IndiGo, India’s largest carrier by domestic market share.

“The issue has led to mounting operational strain and increasing pressure on airport infrastructure, and hence all stakeholders have been asked to maintain constant vigilance,” one official said, explaining why the Directorate General of Civil Aviation (DGCA) has ordered a thorough investigation into the disruptions.

Civil Aviation Minister Ram Mohan Naidu confirmed on Friday that the Government of India has decided to institute a high-level inquiry into the crisis. “The inquiry will examine what went wrong at IndiGo, determine accountability wherever required, and recommend measures to prevent similar disruptions in the future, ensuring that passengers do not face such hardships again,” he said.

Urgent Measures to Stabilise Operations

According to Naidu, the ministry has taken urgent and proactive steps to address ongoing flight disruptions. A control room has been continuously engaged in real-time monitoring of all airports, consolidating data from airport operators, airlines, and Air Traffic Control (ATC). This allows authorities to provide timely information to passengers and coordinate deployment of resources, with a special focus on aiding passengers stranded at terminals.

The Ministry of Civil Aviation has also directed Airports Authority of India (AAI) airport directors to work closely with IndiGo to keep passengers updated on cancellations and delays. Key passenger-handling facilities, including seating, waiting areas, food and beverage counters, have been monitored to minimise inconvenience for stranded travellers. Senior officials from AAI, IndiGo, and the Central Industrial Security Force (CISF) have been asked to remain present at terminals to address grievances on the spot.

Scale of Disruptions

Data from the ministry highlights the severity of the IndiGo crisis:

• December 3: Out of 1,778 scheduled flights from all AAI airports, 190 were cancelled and 877 were delayed.
• December 4: Of 1,585 scheduled flights, cancellations rose to 396 and 791 flights were delayed.
• December 5: By noon, 682 of 1,354 scheduled flights had been cancelled, while 244 were delayed.

The cascading effects of cancellations were visible at airports across India. For instance, Pune airport temporarily halted landings when all available parking bays were occupied by IndiGo aircraft that could not operate due to crew unavailability. Officials coordinated with IndiGo to move aircraft to Regional Connectivity Scheme (RCS) airports to free up space and ensure other airlines could continue normal operations.

Passengers across the country reported long queues, confusion, and rising anxiety, with many forced to make last-minute arrangements for alternate flights or accommodations. Flight cancellations also led to a sharp surge in domestic airfare, with last-minute tickets for some routes costing more than ₹80,000.

Expected Restoration of Services

Naidu assured that flight schedules are expected to stabilise within the next three days. “We anticipate that complete restoration of services will be achieved by December 9,” he said.

Passengers affected by cancellations will receive full refunds automatically, without the need for individual requests. Those stranded due to prolonged delays will be provided hotel accommodations directly arranged by the airlines, according to the ministry.

The DGCA has also granted IndiGo temporary exemptions from certain FDTL provisions to alleviate the operational strain on its A320 fleet, a measure aimed at normalising flight schedules while maintaining safety margins.

Root Causes Identified

Officials emphasised that the disruption stemmed from a combination of factors:

1. Poor rostering under new FDTL rules: The revised regulations increased mandatory weekly rest hours, restricted night duties, and limited pilot flying hours, which caused a shortage of crew available for scheduled flights.
2. Software glitches: IndiGo’s crew scheduling and rostering software failed to handle the operational demands, leading to misaligned crew assignments and cascading cancellations.
3. Baggage system issues: Delays in baggage handling added operational pressure at airports and compounded passenger frustration.

“This unprecedented situation highlights the importance of robust planning, coordination, and technological preparedness in airline operations,” said one official.

The ongoing inquiry by the DGCA and the Ministry of Civil Aviation is expected to identify accountability, recommend systemic improvements in crew management and technology, and suggest measures to prevent such large-scale disruptions in the future.