What is EAT in Aviation? (Expected Approach Time)

Expected Approach Time (EAT) is a term commonly used in aviation to refer to the estimated time at which an aircraft is expected to commence its final approach and land at its destination airport. It is a crucial aspect of flight operations, as it helps air traffic controllers and pilots plan and coordinate their activities to ensure safe and efficient aircraft movements.

Importance of Expected Approach Time

Expected Approach Time plays a significant role in the overall management and coordination of air traffic. It helps to optimize the effective use of airspace and runway capacity, reduce holding patterns and delays, and enhance safety in busy airport environments.

By providing an estimated time for an aircraft to begin its final approach, air traffic controllers can sequence arrivals at their destination airport, ensuring a smooth flow of traffic and preventing congestion. This proactive approach helps to minimize the need for holding patterns, where aircraft circle around designated points in the sky while awaiting clearance to land. Less time spent in holding patterns not only reduces fuel consumption and emissions but also improves the overall efficiency of airport operations, resulting in cost savings for airlines.

Additionally, knowing the Expected Approach Time allows pilots to plan their descent and approach profiles accordingly. They can calculate their fuel requirements, configure the aircraft for landing, and coordinate with the air traffic control for the most efficient and safe arrival procedure. This coordination helps prevent conflicts and ensures that each aircraft lands within the desired timeframe.

Factors Affecting Expected Approach Time

Several factors can influence the Expected Approach Time for an aircraft. These factors need to be taken into account by air traffic controllers when determining the sequencing of arrivals and providing aircraft with their estimated times for final approach.

Air Traffic Volume

Airports with high air traffic volume are likely to experience more congestion and delays, which can impact the Expected Approach Time. When the number of arriving aircraft exceeds the airport’s capacity to handle them simultaneously, air traffic controllers may need to space out the arrivals and adjust the Expected Approach Time accordingly. Similarly, unexpected increases in air traffic due to weather diversions or other operational issues can disrupt the planned sequencing of arrivals, thus affecting the Expected Approach Time.

For example, during severe weather conditions, such as thunderstorms or heavy snowfall, airports often implement flow control measures, such as Ground Delay Programs (GDP) or Airborne Delay Programs (ADP), to manage the flow of traffic. These programs may delay the Expected Approach Time for some aircraft, allowing air traffic controllers to maintain a safe distance between aircraft and manage the flow of arrivals efficiently.

Runway Availability

The availability of runways also has a significant impact on the Expected Approach Time. Airports with multiple runways can handle a higher volume of traffic simultaneously, reducing delays and allowing air traffic controllers to assign more favorable Expected Approach Times. On the other hand, if an airport has limited runway capacity due to maintenance work or runway closures, air traffic controllers may need to adjust the Expected Approach Time to accommodate the reduced availability.

Aircraft Type and Performance

The type and performance capabilities of the aircraft also influence the Expected Approach Time. Different aircraft have varying landing and approach speeds, and air traffic controllers consider these factors when assigning the Expected Approach Time. Air traffic controllers strive to maintain a safe separation distance between aircraft, taking into account their performance capabilities and wake turbulence generation. Aircraft with a higher approach speed or those that generate significant wake turbulence may require additional spacing or separation from other aircraft, which can impact the Expected Approach Time.

Furthermore, the Expected Approach Time can be affected by external factors such as weather conditions, traffic flow management initiatives, and unforeseen events like aircraft diversions or emergencies. Air traffic controllers constantly monitor these factors and adjust the Expected Approach Time as necessary to ensure the safe and efficient flow of air traffic.


Expected Approach Time is a critical element of aviation operations that helps ensure the safe and efficient flow of air traffic. By providing an estimated time for aircraft to commence their final approach, air traffic controllers can manage arrivals, optimize airspace and runway capacity, and reduce delays and holding patterns. Factors such as air traffic volume, runway availability, and aircraft type and performance significantly influence the Expected Approach Time, and air traffic controllers carefully consider these factors to provide accurate and timely information to pilots. By prioritizing safety, coordination, and efficiency, Expected Approach Time plays a crucial role in maintaining the smooth operation of aviation.

For More: What is MMEL in Aviation? (Master Minimum Equipment List)