ASPM Airport Analysis: Definitions of Variables

The following definitions define the fields in the ASPM reports of Airport Analysis:

• % Delayed Gate Arrivals. Number of arrivals delayed 15 minutes or more when compared to schedule or flight plan, expressed as a percent of the total Arrivals For Metric Computation.
• % Delayed Gate Departures. Number of departures delayed 15 minutes or more when compared to schedule or flight plan, expressed as a percent of the total Departures For Metric Computation.
• % of Arrivals with EDCT. Percentage of arrivals with an Expect Departure Clearance Time (EDCT) arrival delay. EDCT delay is computed by comparing the EDCT Wheels On Time to the Flight Plan Wheels On time (the time on the Flight Plan gate out message from TFMS + Unimpeded Taxi Time). A flight may have been issued an EDCT and not accumulated any EDCT delay if the Flight Plan Wheels On time was after the EDCT Wheels On time.
• % of Departures with EDCT. Percentage of departures with an Expect Departure Clearance Time (EDCT) departure delay. EDCT delay is computed by comparing the EDCT Wheels Off Time to the Flight Plan Wheels Off time (the time on the Flight Plan gate out message from TFMS + Unimpeded Taxi Time). A flight may have been issued an EDCT and not accumulated any EDCT delay if the Flight Plan Wheels Off time was after the EDCT Wheels Off time.
• % On-Time Airport Departures. Number of flights that depart within 15 minutes of the Scheduled Wheels Off time. Expressed as a percent of the total number of Departures for Metric Computation.
• % On-Time Gate Arrivals. Number of flights that arrive at the gate less than 15 minutes past the scheduled or flight plan time, expressed as a percent of the total number of Arrivals for Metric Computation.
• % On-Time Gate Departures. Number of flights that departed within 15 minutes past Scheduled Gate Out time, expressed as a percent of the total number of Departures for Metric Computation.
• Arrivals For Metric Computation. Flight arrivals used for calculating metrics in ASPM. Only the following flight records are included: Itinerant flights to or from one of the ASPM 77 Airports or operated by one of the ASPM Carriers at any airport with flight plan and/ or actual arrival and departure times. General aviation and military flights are excluded. Arrivals for Metric Computation are aggregated based on the scheduled arrival time if available, otherwise the flight plan arrival time is used.
• Arrivals with EDCT. Number of arrivals with an Expect Departure Clearance Time (EDCT) departure delay. EDCT delay is computed by comparing the EDCT Wheels Off Time to the Flight Plan Wheels Off time (the time on the Flight Plan gate out message from TFMS + Unimpeded Taxi Time). A flight may have been issued an EDCT and not accumulated any EDCT delay if the Flight Plan Wheels Off time was after the EDCT Wheels Off time.
• Average Airborne Delay. The difference between Actual Airborne Time and the flight plan Estimated Time Enroute (Filed ETE), in minutes.
• Average Airport Departure Delay. The Actual Wheels Off minus the Scheduled Gate Out plus the Unimpeded Taxi Out time, in minutes. Negative values contribute to the average if the report has “Include Early Flights” checkbox selected on the filter tab in the Airport Analysis section.
• Average Block Delay. The difference between Actual Gate-To-Gate time and Scheduled Gate-To-Gate, in minutes.
• Average Difference Between Wheels Off and EDCT Departure Time (Min). For Departures with an EDCT, the total difference between Wheels Off and EDCT Departure Time, divided by the number of Departures with an EDCT.
• Average Difference Between Wheels On and EDCT Arrival Time (Min). For Arrivals with an EDCT, the total difference between Wheels On and EDCT Arrival Time, divided by the number of Arrivals with an EDCT.
• Average EDCT for All Arrivals. The average Expect Departure Clearance Time (EDCT) delay at the departure airport for all arrivals.
• Average EDCT for All Departures. The average Expect Departure Clearance Time (EDCT) delay at the departure airport for all departures.
• Average EDCT for Arrivals Where EDCT>0. The average Expect Departure Clearance Time (EDCT) delay at the departure airport for arrivals having an EDCT delay.
• Average EDCT for Departures Where EDCT>0. The average Expect Departure Clearance Time (EDCT) delay at the departure airport for departures having an EDCT delay.
• Average Gate Arrival Delay. The sum of minutes of Gate Arrival Delay of 1 minute or more, divided by all arrivals. Gate Arrival Delay is the difference between the Actual Gate In Time and the Scheduled or Flight Plan Gate In Time.
• Average Gate Departure Delay. The sum of minutes of Gate Departure Delay of 1 minute or more, divided by all departures. Gate Departure Delay is the difference between the Actual Gate Out time and Scheduled or Flight Plan Gate Out time, in minutes.
• Average Minutes of Delay per Delayed Gate Arrival. The average delay for all flights with an actual Gate In Time delayed 15 minutes or more compared to the schedule or flight plan Gate In Time.
• Average Minutes of Delay per Delayed Gate Departure. The average delay for all flights with an actual Gate Out Time delayed 15 minutes or more compared to the schedule or flight plan Gate Out Time.
• Average Taxi In Delay. The sum of minutes of Taxi In Delay of 1 minute or more, divided by all arrivals. Taxi in Delay equals actual Taxi In Time minus Unimpeded Taxi In Time.
• Average Taxi Out Delay. The sum of minutes of Taxi Out Delay of 1 minute or more, divided by all departures. Taxi Out Delay equals Actual Taxi Out Time minus Unimpeded Taxi Out time.
• Average Taxi Out Time. The difference between Actual Gate Out time and Actual Wheels Off time, in minutes, divided by the total number of flights. Taxi out time is observed for flights for which OOOI data are available, otherwise it is estimated. See ASPM: Estimation Techniques.
• Delayed Gate Arrivals. Number of flights with a Gate In Time delayed 15 minutes or more compared to the schedule or flight plan Gate In Time.
• Delayed Gate Departures. Number of flights delayed 15 minutes or more compared to the schedule or flight plan Gate Out time.
• Departures For Metric Computation. Flight departures used for calculating metrics in ASPM. Only the following flight records are included: Itinerant flights to or from one of the ASPM 77 Airports or operated by one of the ASPM Carriers at any airport with flight plan and/or actual arrival and departure times. General aviation and military flights are excluded. Departures for Metric Computation are aggregated based on the scheduled departure time if available, otherwise the flight plan departure time is used.
• Departures with EDCT. The number of departures with an Expect Departure Clearance Time (EDCT) delay. EDCT’s instructing aircraft to remain on the ground at the departure airport until a specified time, are issued when congestion, weather, or other problems at the arrival airport or en route will impede flights from arriving at the destination airport as originally planned. EDCT delay is computed by comparing the EDCT Wheels Off Time to the Flight Plan Wheels Off time (the time on the Flight Plan gate out message from TFMS + the unimpeded taxi out time). A flight may have been issued an EDCT and not accumulated any EDCT delay if the Flight Plan Wheels Off time was after the EDCT Wheels Off time.
• Flights with EDCT Arriving More than 5 Minutes Early (Count and %). Departures with an Expect Departure Clearance Time (EDCT) that arrive (wheels on) more than 5 minutes before the arrival time from the most recent EDCT message as reported by TFMS.
• Flights with EDCT Arriving More than 5 Minutes Late (Count and %). Departures with an Expect Departure Clearance Time (EDCT) that arrive (wheels on) more than 5 minutes after the arrival time from the most recent EDCT message as reported by TFMS.
• Flights with EDCT Departing More than 5 Minutes Early (Count and %). Departures with an Expect Departure Clearance Time (EDCT) that depart (wheels off) more than 5 minutes before the most recent EDCT message as reported by TFMS.
• Flights with EDCT Departing More than 5 Minutes Late (Count and %). Departures with an Expect Departure Clearance Time (EDCT) that depart (wheels off) more than 5 minutes after the most recent EDCT message as reported by TFMS.
• Scheduled Arrivals. Number of arrivals listed in a published schedule. Most cargo carriers do not have a published schedule.
• Scheduled Departures. Number of departures listed in a published schedule. Most cargo carriers do not have a published schedule.