Air traffic delays can stem from various issues such as congested airports, weather conditions, maintenance problems, and staffing challenges. To address these complications, airlines employ a strategy of extending flight durations. For instance, while the travel time for a Delhi-Mumbai flight can range from less than two hours to nearly three, this discrepancy often relates to an airline’s approach to On-Time Performance (OTP) metrics rather than actual flight speed.
Most airlines utilize similar aircraft, like Boeing or Airbus models, which fly at comparable speeds and altitudes along similar routes. Therefore, the variation in travel times raises questions. OTP refers to the measures airlines take to present themselves as punctual, which can include inflating journey times to reduce the risk of late arrivals.
Airlines must account for many factors impacting flight operations from takeoff to landing. External conditions like adverse weather and congestion at key airports like Delhi and Mumbai are beyond their control. However, airlines also bear responsibility for operational issues such as aircraft maintenance and crew availability.
To quantify on-time departures, the Directorate General of Civil Aviation (DGCA) maintains that flights must depart within a 15-minute window of their scheduled time. Calculating scheduled departure and arrival times involves taking into consideration historical and seasonal flight durations, as well as taxiing times at departing and arriving airports. The terminology “chocks off” to “chocks on” reflects this time frame, indicating the departure and arrival times around the aircraft’s parking position.
Typically, a Delhi-Mumbai flight’s actual flying time averages one hour and 40 minutes. With an additional 10 minutes for taxiing at both airports, the total travel time reaches approximately two hours. To factor in potential airport congestion and holding patterns upon landing, some airlines have further increased this buffer to 27 minutes. This practice has become widespread as competition intensifies among carriers dealing with congested flight schedules.
As a result, unless one is flying during extreme weather events or with particularly unreliable airlines, travelers can often expect timely arrivals, reinforced by airlines’ claims of maintaining OTP. Queries made to major and emerging airlines, including Air India, IndiGo, and Akasa, regarding this issue have gone unanswered.
The introduction of low-cost carriers (LCCs) to Indian airspace in 2003 brought about an increase in air traffic and subsequent congestion. About two decades ago, the stated travel time for a Delhi-Mumbai flight was set at one hour and 55 minutes. The growing congestion led to delays, prompting airlines to add time buffers to ensure on-time arrivals.
This inflation of travel times can result in inconsistencies, as the same aircraft type can have vastly different journey durations on the same route. Factors influencing these variations include flight routing, weather conditions, and wind patterns. For example, an aircraft benefiting from tailwinds may complete its journey faster, while headwinds could extend travel times.
The DGCA publishes monthly reports on domestic flight performance that encompass OTP metrics derived from six key airports: Delhi, Mumbai, Bengaluru, Hyderabad, Chennai, and Kolkata. Accurate data is essential for airlines to market themselves effectively as punctual.
Inflating travel durations is not limited to domestic routes; some long-haul flights, like those between Delhi and London, may also report flying times under ten hours to avoid the requirement of having a third pilot onboard, lowering operational costs accordingly. The DGCA monitors such discrepancies among airlines to ensure compliance with reporting requirements.
On the ground, inflating travel times can create challenges. Airlines and airport operators often blame one another for air traffic congestion, which is factored into journey time calculations. Airlines contend that delays stemming from clearances at congested hubs are outside their control, while airport officials highlight the disruption caused by late flights impacting slot allocations.
Moving forward, improvements in airport infrastructure, particularly in major regions like Delhi-NCR and Mumbai, as well as the development of new facilities in Hyderabad and Bengaluru, are expected to alleviate some of these congestion-related issues. As new carriers enter the market and existing airlines like IndiGo and Tata’s Air India Group maintain contemporary fleets, delays may diminish, potentially eliminating the necessity for inflated travel times to ensure perceived punctuality.