Ground Delay Program

Ground Delay Program

Overview

Ground Delay Programs (GDP) are implemented to control air traffic volume to airports where the projected traffic demand is expected to exceed the airport's acceptance rate for a lengthy period of time. Lengthy periods of demand exceeding acceptance rate are normally a result of the airport's acceptance rate being reduced for some reason. The most common reason for a reduction in acceptance rate is adverse weather such as low ceilings and visibility.

How It Works

Flights that are destined to the affected airport are issued Controlled Departure Times (CDT) at their point of departure. Flights that have been issued CDTs are not permitted to depart until their Controlled Departure Time. These CDTs are calculated in such a way as to meter the rate that traffic arrives at the affected airport; ensuring that demand is equal to acceptance rate. The length of delays that result from the implementation of a Ground Delay Program is a factor of two things; how much greater than the acceptance rate the original demand was, and for what length of time the original demand was expected to exceed the acceptance rate.

Legend

GROUND DELAY PROGRAM TO: Airport for which the Ground Delay Program has been issued.

DUE TO: The reason that the Ground Delay Program had to be implemented. Common acronyms used in this field are:

RWY or RY	Runway
WX	Weather
CIGS	Ceilings
VIS or VSBY	Visibility

MAX DELAY: The maximum delay, in minutes, that has been issued to affected flights.

AVERAGE DELAY ARRIVING TRAFFIC: The average delay, in minutes, that has been issued to affected flights.

TERSE MESSAGE OPTION:

In this example, flights departing from all airports with a destination of LaGuardia airport (LGA), New York, that were originally scheduled to arrive at Luardia between 1800 and 2200, will be issued delays. The maximum delay thataG will be issued is 74 minutes, the average delay will be 36 minutes. The Ground Delay Program was issued because high winds have reduced LaGuardia's acceptance rate.

LONG MESSAGE FORMAT:

Ground Stop

Overview

Ground Stops are implemented for a number of reasons. The most common reasons are:

To control air traffic volume to airports when the projected traffic demand is expected to exceed the airport's acceptance rate for a short period of time.
To temporarily stop traffic to allow time for the implementation of a longer-term solution, such as a Ground Delay Program.
The affected airport's acceptance rate has been reduced to zero.

How It Works

Flights that are destined to the affected airport are held at their departure point for the duration of the Ground Stop.

Legend

GROUND STOP TO: Airport for which the Ground Stop has been issued.

DUE TO: The reason that the Ground Stop had to be implemented.

TERSE MESSAGE OPTION:

In this example, flights departing from airports that are under the jurisdiction of Chicago ARTCC and Chicago's first tier ARTCCs, with a destination of Chicago, have been stopped.

LONG MESSAGE FORMAT:

Delay Information

Overview

This table shows airports that are currently experiencing delays.

How It Works

Terminal facilities are required to report delays of 15 minutes or more to the Air Traffic Control System Command Center (ATCSCC). Delays are tracked in 15 minute increments. Delay times are preceded with either a '+' or a '-' to indicate that the delays are increasing or decreasing. Because the delays are tracked in 15 minute increments, a single delay entry actually represents a time range. For example, an entry of +15 indicates that delays are greater than 15 minutes but less than 30 minutes and are increasing. An entry of -30 indicates that delays are less than 30 minutes but greater than 15 minutes and are decreasing. Normally delays of less than 15 minutes are not shown. The one exception to this is when delays for an airport have just gone below 15 minutes. This will be indicated by an entry of -15.

Legend

DEPARTURE DELAYS AT: Airport at which d eparture traffic is experiencing delays. Depending on the length of delay, traffic will be experiencing longer than normal taxi times or holding at the gate.

DUE TO: The reason for the delays.

TERSE MESSAGE OPTION:

In this example, Fort Lauderdale/Hollywood International airport is experiencing departure delays. Delays are currently less than 45 minutes but greater than 30 minutes and are increasing. Volume are the cause of the delays.

LONG MESSAGE FORMAT: