WO2000062234A1

WO2000062234A1 - Air traffic management system

Info

Publication number: WO2000062234A1
Application number: PCT/AU2000/000290
Authority: WO
Inventors: John Cappelletti; Peter Templer; Eric Kiem; Peter Atkins
Original assignee: Air Services Australia
Priority date: 1999-04-08
Filing date: 2000-04-07
Publication date: 2000-10-19
Also published as: EP1188137B1; DE60033390D1; ATE354151T1; EP1188137A1; HK1045739A1; AUPP965299A0; EP1188137A4

Abstract

A method for scheduling the flow of air traffic into a destination airport over a particular time period includes the steps of: a) establishing an arrival schedule over the particular time period at said destination airport for a plurality of aircraft; b) determining prior to the particular time period, the departure airports from which each of said aircraft departs, so as to define a travel path from a departure airport to the destination airport for each aircraft; c) dividing the travel path of each aircraft into a plurality of travel sequences; d) estimating from historical data, an initial time estimate for each travel sequence, based on any travel time influencing factor; e) establishing an initial total estimated travel time for each aircraft by summing the respective travel sequence times for each aircraft; and f) sequencing the departure time of each aircraft in accordance with the initial total estimated travel time, so that the time of aircraft arrival is estimated and an arrival schedule is established.

Description

Air Traffic Management System

Field of the invention

The present invention relates to a method for scheduling the flow of air traffic into a destination airport over a particular time period. Background of the invention

The airline industry provides services to its customers which are designed to satisfy air travel requirements, such services include ensuring adequate flow of air traffic at an airport. However, airport capacity varies with the prevailing weather and associated noise abatement requirements. As demand for travel and airline capability has increased and exceeded airport/airspace infrastructure capacity, delays to scheduled aircraft arrivals and departures have occurred.

The inability of an airline service provider to meet its scheduling commitments may be the result of many factors, some of which are within the control of the Air Traffic Controller responsible for the flow of traffic at a particular airport, and some are not. These difficulties usually result due to delays to arrivals and departures at the destination and departure airports respectively.

The sequencing of air traffic landing at a particular airport is a function of Air Traffic Control (ATC), with controller ensuring that runway movement rates are optimised as aircraft arrive at their destination. Any resultant delay is absorbed by aircraft holding or flying additional track miles, thus incurring unnecessary cost to operations. The ATC typically regulates the flow of traffic at an airport by:

• making an assessment of each aircraft's arrival time;

• determining the landing sequence and estimated landing time of a number of aircraft over a particular time period; and • as appropriate, instructing en-route controllers to delay identified aircraft.

Real time advice regarding particular aircraft arrival times is not routinely provided to airline operators.

i ute Sheet There are limits to the capacity of any airport or airway system and there are often peak periods where demand does exceed capacity, particularly for airports which service large cities such as Sydney Airport in Australia.

Excess demand at Sydney airport for example, is currently addressed by a Controlled Departure Time Programme. Under this arrangement airline schedules are reviewed by an air traffic controller at Sydney, the evening prior to operation and, when the scheduled demand exceeds the anticipated capacity, a revised departure time is provided to the operating company. Whilst this process has provided some relief from excessive airborne holding, delays still occur and the arrival schedule of flights into Sydney airport has become increasingly difficult to manage delays, which may occur due to: limits on aircraft movement rates at some airports; limits on hours of operation (eg. curfews); limited gate and parking facilities at some aerodromes; surges due to weather at both destination and departure ports; noise abatement requirements; • marketing pressures to schedule operations to the most attractive times; and lack of schedule co-ordination.

Once an initial delay has occurred in the planned schedule on a particular day of a destination airport, those flights that are due to arrive at the destination airport may be subjected to a further delay as a result of the initial delay. Any resultant delay is absorbed by aircraft holding or flying additional track miles, thus incurring unnecessary cost to operations.

Summary of the invention

The object of the invention is to provide an improved method and system for scheduling the flow of air traffic. According to a first aspect of the present invention, there is provided a method for scheduling the flow of air traffic into a destination airport over a particular time period, the method including the steps of:

(a) establishing an arrival schedule over the particular time period at said destination airport for a plurality of aircraft; (b) determining prior to the particular time period, the departure airports from which each of said aircraft departs, so as to define a travel path from a departure airport to the destination airport for each aircraft;

(c) dividing the travel path of each aircraft into a plurality of travel sequences;

(d) estimating from historical data, an initial time estimate for each travel sequence, said initial time estimate being dependent upon any one or more of the following variables:

(i) aircraft type; (ϋ) time for departing aircraft to taxi from its departure gate, to becoming airborne;

(iii) time for a departing aircraft, after becoming airborne, to reach a set course point;

(iv) flight time for an aircraft from the set course point to reach a designated route fix;

(v) time taken by an arriving aircraft from passing over the designated route fix, to land on the specified landing runway of the destination airport;

(vi) time taken for an arriving aircraft to taxi from the specified landing runway to its gate or its parking position;

(vii) flight path;

(viii) weather conditions; or

(ix) any other travel time influencing factor; (e) establishing an initial total estimated travel time for each aircraft by summing the respective travel sequence times for each aircraft;

(f) sequencing the departure time of each aircraft in accordance with the initial total estimated travel time, so that the time of aircraft arrival is estimated and an arrival schedule is established.

heet The method may also further include the step of:

(g) monitoring the variable conditions so as to be appraised of when the total estimated travel time for one or more aircraft is likely to vary from said initial total estimated travel time. The method may also further include the step of:

(h) amending the departure times of any of the aircraft for which the total estimated travel time has been varied so that the aircraft arrive in substantial accordance with the arrival schedule.

According to a second aspect of the present invention, there is provided a system to scheduling the flow of air traffic into a destination airport over a paπicular time period including: an aircraft arrival schedule means adapted to establish record an arrival schedule over the particular time period at said destination airport for a plurality of aircraft, said aircraft arrival schedule means capable of determining prior to the particular time period, the departure airports from which each of said aircraft departs, so as to define a travel path from a departure airport to the destination airport for each aircraft and wherein the travel path of each aircraft is divided into a plurality of travel sequences; data base means adapted to estimate from historical data, an initial time estimate for each travel sequence, said initial time estimate being dependent upon any one or more of the following variables:

(i) aircraft type;

(ii) time for departing aircraft to taxi from its departure gate, to becoming airborne;

bstitute Sheet (vi) time taken for an arriving aircraft to taxi from the specified landing runway to its gate or its parking position;

(vii) flight path; (viii) weather conditions; or

(ix) any other travel time influencing factor: and wherein the aircraft arrival schedule means is further adapted to establish an initial total estimated travel time for each aircraft by summing the respective travel sequence times for each aircraft, and to sequence the departure time of each aircraft in accordance with the initial total estimated travel time, so that the time of aircraft arrival is estimated and an arrival schedule is established.

The aircraft arrival schedule means may monitor the variable conditions so as to be appraised of when the total estimated travel time for one or more aircraft is likely to vary from said initial total estimated travel time. The aircraft arrival schedule means may also allow amendment of the departure times of any of the aircraft for which the total estimated travel time has been varied so that the aircraft arrive in substantial accordance with the arrival schedule.

Preferably the variable conditions are monitored in real time. More preferably, the variable conditions may be monitored by a real time computer system. Preferably the method is implemented using a computer software program.

Optionally, the historical data may be recorded in a database. The database may be a relational database and further comprise a database management system for the upkeep and management of the historical records.

Typically the airport traffic is monitored and controlled by at least one air traffic control person who also sets the landing time at the destination airport.

Usually the plurality of aircraft is operated by a plurality of airline operators. The operators of the airlines will usually communicate the times at which they intend to arrive at the destination airport. The communication may be by any number of means such as facsimile, email, or via a direct modem link with the air traffic control person. Alternatively, the communication via

i ute Sheet modem may allow an airline operator to monitor the departure times set for their designated aircraft from the departure airports.

Preferably the estimated historical data for each travel sequence is taken from measured data from a multiplicity of flights. Preferably the particular period of time is a 24 hour period of time broken into daily time quartiles of 6 hour periods each, allowing for easy management of the system by the air traffic control person and the airline operator.

Preferably the estimated arrival schedule for each aircraft is assigned a time period in which the aircraft can land, known as the programmed time of landing. Preferably the variable conditions that are monitored includes delays. Optionally the variable conditions may further include notifications of newly scheduled and re-scheduled flights, amendment of a terminal area management plan (the plan used to manage the flow of taxiing traffic about an airport. Additionally any flight cancellations may also be monitored.

Brief description of the drawings Notwithstanding any other forms which may fall within the scope of the present invention, preferred forms of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Fig. 1 shows schematic illustrations of a method for scheduling the flow of air traffic into a destination airport over a particular time period. Detailed description of the embodiments

A first embodiment of the method of the present invention is shown in figure 1, which is a method for scheduling the flow of air traffic into a destination airport over a particular time period.

The method includes the step of the first stage 10 in which the arrival schedule is sent from an airline operator to an air craft control person of a destination airport. The aircraft controller determines at stage 10. the available times during a given period in which the planes can actually land at the destination airport so that an arrival schedule is established.

The method then involves step 20. in which the travel path of the plurality of flights are determined.

Substitute Sheet The travel paths are then broken down into travel sequences at step 30, for each of the flights. At step 30 the travel path of the flight is broken down into separate record components to be recorded as:

• the time in which the aircraft leaves from the departure gate to the time the aircraft becomes airborne;

• the time for a departing aircraft, after becoming airborne, to reach a set course point;

• the time for an aircraft from the set course point to reach a designated route fix;

• the time taken by an arriving aircraft from passing over the designated route fix, to land on the specified landing runway of the destination airport; • the time taken for an arriving aircraft to taxi from the specified landing runway to its gate or its parking position;

At step 40, the time for each of these sequences is estimated from stored historical data 50. The historical data 50 is stored times for each of the time periods:

(h) the time in which the aircraft leaves from the departure gate to the time the aircraft becomes airborne;

(i) the time for a departing aircraft, after becoming airborne, to reach a set course point:

(j) the time taken by an arriving aircraft from passing over a designated route fix, to land on the specified landing runway of the destination airport; (k) the time taken for an arriving aircraft to taxi from the specified landing runway to its gate or its parking position;

Each of time periods (a) to (d) are dependent upon: (a) the aircraft type

(b) the flight path, and

(c) the weather conditions

At step 60, in which each of the times determined from the flight times (a) to (d) are added so as to determine the total time for each flight. From this total time, the time at which each flight should depart from its departure airport is determined and the departure time is then set.

The estimated flight times for each sequence are then monitored at stage 70 during the progress of the flights for the time period. The time difference between the estimated times at 40 and the actual times which are monitored for each record component at 80 are then assessed at 90. If there is a difference between the estimated and the actual flight times at 90, and other flights have not departed from their departure airports, then the flight departure time is amended at step 100 and a new departure time is set at 60

In this way the delay of an aircraft in flight is reduced and the traffic flow about an airport becomes easier to manage. The reduction delay in this example of the invention and in the embodiment descπbed below, significantly reduces the operating costs of the airline operator, ensures schedule stability, and improves gate utilisation, aircraft utilisation, crew utilisation and passenger connections. Other benefits are that the real time data provides real time information regarding a flight which can assist in conducting scenarios for alternative flight landing times and take off schedules.

The Central Traffic Management System

Another method and system for scheduling the flow of air traffic into a destination airport over a particular time period, is the "Central Traffic Management System" (CTMS), a software program and management system developed by the inventors of the present invention.

Where in the specification the following acronyms are used to describe the CTMS, they have the following meaning:

t Sheet

Substitute Sheet

Substitute Sheet

The CTMS is closely coupled to the live ATC system. The CTMS assists in the smooth operation of the ATC system by recalculating the departure times of scheduled flights inbound to CTMS aerodromes so as to minimise or eliminate the need for flow control and the inherent airborne delays.

CTMS uses data items (see "Data Items " described below) to recalculate the departure time of scheduled flights as follows:

ubstitute Sheet When the TAMPs for all CTMS aiφorts are registered, CTMS estimates an arrival schedule for each flight of an airline over a particular time period by calculating the Programmed Times of landing (PTL) available within each half hour period of the particular time period, for each CTMS aiφort. Once the Airline Schedules are loaded into CTMS, CTMS calculates the estimated landing time for each flight based on the scheduled gate departure time. This is achieved by estimating from historical data, an initial time estimate for each stage of the flight path. The data is determined from historical data measured for the following stages of flight:

(a) the aircraft type;

(b) the time for the departing aircraft to taxi from its departure gate, to becoming airborne;

(c) the time for a departing aircraft, after becoming airborne, to reach a set course point of the flight, the time being dependent on the aircraft type;

(d) the time taken by an arriving aircraft from passing over a designated route fix, to land on the specified landing runway of the destination aiφort, the time being dependent on the aircraft type;

(e) time taken for the arriving aircraft to taxi from the specified landing runway to its gate or its parking position;

(f) the flight path, being dependent on the aircraft type

Any one of the above historical data may (in other embodiments of the invention), be also dependent on the weather conditions:

3 From the estimated landing times, CTMS allocates a programmed time of landing to each flight and calculates all of the programmed flight event times based on the PTL.

4 CTMS notifies the airline operators, of the PTLs allocated for their particular flights and the Gate Departure Times (revised as necessary) required to achieve these PTLs.

5 CTMS repeats the above processes (steps 1 to 4) so as to amend the departure times for individual notifications of newly scheduled and re-scheduled flights.

Substitute Sheet 6 CTMS also repeats these processes (steps 1 to 4), for all affected flights at routine TAMP re-issue times and when an individual TAMP is amended so as to amend the departure times.

7 CTMS checks and when necessary modifies flight schedules based on FPL, CHG messages received via the AFTN. FPL messages for unscheduled flights are also decoded and added to the lists of flights.

CTMS follows the progress of all flights recording, where known, the actual times at which significant events occur for each flight (ie. Gate departure, take off, landing and gate arrival).

Data Types

The CTMS uses various data types, these are:

• SLOT Allocation data

• Aircraft Movement data

• Airline Schedule data

• AFTN data

• TAAATS data

• Reference data

• Terminal Area Reference data

• Estimated Time to Fix (ETF. data

• Terminal Area Management Plan (TAMP) data

Airline Schedule Data

This data is supplied by the major airlines for the scheduled movements of their aircraft and possibly for other aircraft for which they have a responsibility. It is provided on a daily basis for the following two days of operations, giving a daily update of the next day's operations.

AFTN Data

Data is received as individual messages relating to specific flights. The AFTN message types that CTMS processes are shown in the following table:

Substitute Sheet

TAAATS data

CTMS receives data from the TAAATS system. The following data is required

Other Aircraft Movement Data

Other aircraft movement data is as follows :

• Individually scheduled flights input directly by ATS

Substitute Sheet • Actual aircraft movement data

GDTA

TOTA (ACARS equipped aircraft only) • ATL (ACARS equipped aircraft only)

GATA Terminal Area Reference Data Terminal area reference data has a number of elements as shown in the following table:

Substitute Sheet

Estimated Time to Fix Data

These are time intervals for aircraft to fly from the set course point at an ADEP to the inbound Fix for the ADES.

The ETF interval is stored in five broad categories for each route.

Other Reference Data

Other reference data which may be included in CTMS are:

Aircraft Types

Aiφorts

Outbound Routes for each CTMS airpoπ

Inbound fixes used on approach to each CTMS aiφort

Airline Operators

Substitute Sheet TAMP Data

TAMP Data for each CTMS Aerodrome is as shown in the following table:

Loading Airline Schedules

Airline schedule data covering a 48 period is be transferred at approximately 5.00 PM to the ATC of each CTMS aiφort by the airlines who have flights due to land within the 48 hour period.

Data Fields Extracted from Airline Schedules

When this data is fully loaded. CTMS extracts and stores the following data for each flight for the 48 hour period:

• Aircraft Identification (this may be the FLT NO or the REG)

• Aircraft Type (if given)

stitute Sheet Departure Aiφort

Scheduled Gate Departure Time

Destination Aiφort

Scheduled Gate Arrival Time

REG if notified but not used as ACID

Determining the Aircraft Category

Where the flight details in the airline schedules include an aircraft type, the aircraft type category is obtained by searching the Aircraft Category Table for the entry matching the aircraft Type. Entries in the Aircraft Category Table appears as shown in the following table of examples:

Obtaining the Inbound Fix

CTMS uses the ADES, ADEP and Category fields to access the fix reference table to obtain the default route and inbound fix applicable to this ADEP, ADES and aircraft Category. Where the aircraft category is not known, a default route and fix based on ADEP and ADES only will be used and an aircraft category will be assumed.

Entries in the fix table will appear as shown in the following table of examples:

titute Sheet

Programming of Flights

When the above processes are complete the Flight Programming Function is initiated automatically and the estimates of the time for each flight is recorded within CTMS.

Loading TAMP Data

TAMP data is normally input daily at a set time by the responsible Air Traffic Controller at each CTMS aiφort. TAMP data comprises four quartiles each covering a 6 hour period. Each quartile comprises 12 'lines' containing the RWY configuration, hourly acceptance rate and approach type for a 15 minute period.

Each quartile and line will commence at a specific time that may be offset from the hour and half hour by up to 15 minutes.

Draft Quartiles

A number of draft quartiles may be created for each period.

The controller may evaluate the delay that will result from the combination of different active and draft quartiles using the delay forecast function. When the controller has selected the most appropriate quartile for a period it will be designated as active and the previously active quartile will become superseded.

CTMS will register the four active quartiles, if present, as the TAMP for the location.

Delay Forecast Function

The delay forecast function allows access to the airline schedules for the period covered by the nominated quartiles and calculates the delay (if any) that would be generated at the location for each half hour period. Active and draft quartiles may be in the calculation.

The forecast delay for each 30 minute period is displayed to the controller for evaluation.

Substitute Sheet Amending Active TAMP data

Once quartiles have been made active and registered within CTMS they cannot be amended directly. The only way to change an active quartile is to create a new draft quartile for the relevant period and nominate it as the active one. The previously registered quartile(s) will become superseded.

TAMP data cannot be changed retrospectively, ie. quartiles and lines currently in use or not yet in use may be amended provided they are draft, but those whose period of validity has expired may not.

Calculating PTLs from Active TAMP data

When a new active quartile is registered the CTMS calculates the PTLs available for each 15 minute period from the aiφort acceptance rate, as shown in the following table of examples:

Receipt of AFTN and TAATS Messages

Flight Plan and modification messages are processed in CTMS as follows :

• Flight details are correlated with the airline schedule where possible

• The outbound and inbound route segments for the flight are checked

• For 'untouchable' flights (that is flights which have departed an aiφort which does not have the CTMS) the flight planned ETA will be checked against the GATS

Substitute Sheet Correlating Flight Details

The processes for correlating flight details in an FPL or CHG message with scheduled flight details is shown in the following table:

Substitute Sheet If match found for Then Otherwise

ACID between In scheduled flights - Go to ADEP and ADES at • Change the flight status "Messages for approximate ETD from scheduled to planned. unidentifiable flights" below

• Store the new REG if different to the scheduled REG

• Store the new TYP if different to the scheduled TYP and re-determine the aircraft category. If different then go to "Aircraft Category Changed"

In reserved PTLs list-

• Confirm the reserved PTL

• Set the flight status to planned

• Store the new REG if different to the reserved REG

• Store the new TYP if different to the reserved TYP and re-determine the aircraft category. If different then go to "Aircraft Category Changed"

ute Sheet Aircraft Category Changed

If the new aircraft TYP notified in the flight plan results in a change to the Aircraft category, CTMS recalculates the ETDS, TOFS and ETLS.

Checking the Outbound and Inbound Route Segments

The outbound and inbound route segments from the flight plan are correlated with the assumed route obtained for this flight from the airline schedule and the fix reference table.

• If these are the same then no further action is required

• If these are different then CTMS will identify new set course point and inbound fix and recalculate the ETDS, TOFS, ETLS and GATS event times for the flight

• CTMS will then recheck the ETLS against the PTL. See "Rechecking the ETLS" below. Entries in the fix table will appear as shown in the following table of examples:

Comparing ETA and GATS for Excepted or 'Untouchable ' Flights

If the flight has a time greater than 3 hours or has an approved special flight status, then CTMS compares the flight planned ETA with the GATS.

• If the difference between these times is less than a pre-defined compatibility margin, then no action is required

• If their difference is greater than this margin then the GATS will be set to the ETA and the TOFS and ETLS event times will be recalculated.

Substitute Sheet • The new ETLS will become the PTL for the flight because it is, by definition, an

'excepted' or 'untouchable' flight.

Checking Departure Time

If a Flight Plan Modification message includes an amended departure time, that is different to the ETDS by more than a pre-defined compatibility margin, as defined by a VSP. CTMS will store the new ETD as the GDTS and recalculate all flight event times based on this new GDTS, as shown in the following table :

New PTLs not Allocated

A new PTL will not be allocated to a scheduled flight for which :

• a revised ETD is notified by modification message

• a different aircraft type that result in a change in aircraft category is notified in the FPL message unless a new PTL has been reserved for the flight using the Examine Flight Options Function.

Messages for Unidentifiable Flights

When the flight details correlation detailed above fails to find a match in the airline schedules then the CTMS process as follows :

• For a Flight Plan message

• Originate advice of an unknown flight to CTMS Administration

• If an airline but not a specific flight was identifiable then also originate advice of a non-compatible flight plan to the airline

Substitute Sheet • Add this flight to the schedule and run the Flight Programming Function for this flight alone.

• For a modification advise

• Originate advice of an unknown flight to CTMS Administration

• If an airline but not a specific flight was identifiable then also originate an advice for a non-compatible flight to the airline

Flight Change Notification

Any change to the GDTS for a scheduled flight that results from the above processes shall originate an advice to the airline and CTMS Administration.

Receipt of AFTN DLA Message

AFTN DLA messages the CTMS aiφort. As the format for this type of message does not include a new ETD, CTMS will not take any action on receipt of a DLA message.

Receipt of AFTN CNL Message

Delete the flight plan record for the flight, this will not cancel the schedule information if the schedule has been notified separately from flight plan.

Receipt of AFTN & TAAATS aircraft actual movement advice

Aircraft actual movement advice sourced from the AFTN and or from within the TAAATS system is detailed within the chapter titled "Flight Progress Monitoring".

Flight Programming

When the airline schedules and the TAMPs for all CTMS aiφorts are loaded, CTMS commences the flight programming function.

Calculating Scheduled Flight Event Times

The flight programming function involves using the various data fields loaded in the schedules and TAMPs to access the appropriate reference tables and from these to calculate a series of intervals and event times for each flight based on the scheduled gate departure time, as follows :

Take Off Time (TOTS)

• Departure or set course time (ETDS)

• Time Over Inbound Fix (TOFS)

Substitute Sheet • Time of Landing (ETLS)

The flight schedule is then sorted into an arrival sequence by GATS at each CTMS aiφort.

Allocating PTLs to Flights

Each Flight is allocated a Programmed time of Landing (PTL), 'untouchable' flights are allocated first to ensure that the appropriate PTL is available for allocation. When a PTL has been allocated, the remaining programmed times for each flight are calculated as follows:

• Gate Departure time (GDTP)

Take Off Time (TOTP)

Time Over Fix (TOFP)

Gate Arrival Time (GATP)

The above event times are the same as the scheduled times unless the allocated PTL is later than the ETL by more than a pre-defined compatibility margin.

Allowing Bulk Changes

The CTMS systems allows airline operators to make decisions relating to changing and swapping PTL's within their own system.

CTMS shall accommodate this by allowing :

• Bulk changes

• Swaps between operators

• Booking vacant PTL's whilst these changes are underway.

Notifying the Airlines Operators

When the above process is complete, the airline operators are notified of the allocated PTL and revised gate departure and arrival times for each of their flights.

Calculating the TOTS

To calculate the TOTS, CTMS will be required to perform a number of steps as shown in the following step action table:

Substitute Sheet

Determining the ADEP Terminal

The ADEP passenger terminal is obtained by searching the passenger terminal table for entries matching the airline operator for the flight.

The airline operator is determined from the leading 2 or 3 non-numeric characters in the FLT NO.

If the airline cannot be determined from the FLT NO, then the default terminal for the aiφort will be allocated.

Entries in the Passenger Terminals Table will appear as shown in the following table of examples:

Determining the ADEP GNDMI

The ADEP GNDMI is obtained by searching the ground manoeuvring table for an entry matching the ADEP passenger terminal, the ADEP departure runway (as defined in the TAMP for the schedule departure time) and the aircraft category for the flight.

Entries in the ground manoeuvring table will appear as shown in the following table of examples:

The TOTS for each flight is the Scheduled Departure Time plus the ADEP GNDMI.

Flights from non-CTMS airports

The process is similar for a non-CTMS aiφort except that default values are used for ADEP GNDMI. These values are not specific to any terminal or departure RWY.

Default values for ADEP GNDMI at CTMS airports

Default values for ADEP GNDMI are used for CTMS aiφorts when there is no active TAMP quartile registered for the period in which the departure is to occur.

Calculating the ETDS

To calculate the ETDS, CTMS performs a number of steps as shown in the following step action table:

Substitute Sheet Determining the ADEP TMAMI

The ADEP TMAMI is obtained by searching the terminal area manoeuvring table for an entry matching the ADEP, the ADEP departure runway (as defined in the TAMP for the schedule departure time), the ADES and the aircraft category for the flight.

Entries in the terminal area manoeuvring table appear as shown in the following table of examples:

The ETDS for each flight is the TOTS plus the ADEP TMAMI.

Flights from non-CTMS airports

The process is similar for a non-CTMS aiφort except that default values are used for ADES TMAMI. These values are not specific to any departure RWY or route.

Default values for ADEP TMAMI at CTMS airports

Default values for ADEP TMAMI will be used for CTMS aiφorts when if there is no active TAMP quartile registered for the period in which the departure is to occur.

Calculating the TOFS

To calculate the TOFS, CTMS performs a number of steps as shown in the following step action table:

Substitute Sheet Determining the ETF

The ETF is obtained by searching the ETF table for an entry matching the ADEP, the route fix and the aircraft category for the flight.

Entries in the ETF will appear as shown in the following table of examples:

The TOFS for each flight is the ETDS plus the ETF.

Calculating the ETLS

To calculate the ETLS. CTMS performs a number of steps as shown in the following step action table:

Step Action

Determine the ADES TMAMI

Calculate the ETLS

Determining the ADES TMAMI

The ADES TMAMI is obtained by searching the ADES TMAMI table for an entry matching the inbound fix, the ADES runway and approach type (from the ADES TAMP), and the aircraft category for the flight.

Entries in the ADES TMAMI appear as shown in the following table of examples:

Substitute Sheet

The ETLS for each flight is the TOFS plus the ADES TMAMI.

Calculating Event Times for Unnotified Flights

When a valid flight plan is received for a flight into a CTMS aiφort which has not previously been notified, CTMS must calculate event times for it. The process for calculating these event times involves a number of steps as shown in the following table:

Substitute Sheet Extracting the Flight Details

The flight plan will be decoded and the following details extracted and stored for the flight :

ACID

ADES

ADEP

TYP

ETDF

Inbound Fix

ETLF

REG

Determining the Aircraft Category

The aircraft category is obtained by searching the Aircraft Category table for the entry matching the aircraft TYP.

Determining the Terminals

The default terminals in the passenger terminal table for the ADEP and ADES will be used for unnotified flights.

Determining the ADEP GNDMI and TMAMI

The ADEP GNDMI and TMAMI are obtained by referencing the ADEP TAMP (or using default values) and searching the ground and TMA manoeuvring interval tables for entries matching the flight details.

Determining the ADES GNDMI and TMAMI

The ADES GNDMI and TMAMI are obtained by referencing the ADES TAMP (or using default values) and searching the ground and TMA manoeuvring interval tables for entries matching the flight details.

Calculating Event Times for Unnotified Flights

The standard ICAO usage of ETD as referring to the set course time is applied to all unnotified flights. Event times for unnotified flights will be calculated as follows :

Substitute Sheet The ETDF is the ETD from the flight plan

The GDTF is the ETDF minus the ADEP TMAMI and GNDMI

The TOTF is the ETD minus the ADEP TMAMI

The ETLF is the ETA from the flight plan

The TOFF is the ETLF minus the ADES TMAMI

The GATF is the ETLF plus the ADES GNDMI

Allocating a PTL to an Unnotified Flight

PTLs are allocated to unnotified flights only to prevent those PTLs being allocated to scheduled flights via the Examine Flight Options Function.

Unnotified Flights from CTMS to non-CTMS airports

For unnotified flights departing from CTMS aiφorts for non-CTMS aiφorts. CTMS will calculate only the ADEP GDTF and ADEP TOTF. These flights are not monitored after take off.

Allocating PTLs to Flights

The allocation of PTLs to flights is performed when the scheduled event time calculations for all flights have been completed. The Flight Programming function involves a number of steps as shown in the following table:

t Merging and Sorting the Schedules

The schedules submitted by the various airlines are merged and sorted in ascending order by GATS for each CTMS aiφort.

Exempt or Untouchable Flights

Exempt or untouchable flights are those :

• departing from overseas

• between city pairs that have a nominal flight time stored in the reference data that is greater than 3 hours

• having approved special flight status (eg. VIP PM, VIP GG or MEDICAL)

Allocating the PTL

The latest possible landing time is the gate arrival time from the airline schedule minus the ADES GNDMI.

The earliest possible landing time is the ETLS calculated from the scheduled gate departure time.

Allocate the next available PTL equal to or after the ETLS to the flight.

Because of excessive allowances in the scheduled gate arrival times for some flights and variations in the departure and arrival runways used, basing the PTL allocation on the ETLS instead of the GATS minus the ADES GNDMI can produce a negative time penalty (ie. a time saving) for the airline.

Calculate Programmed Event Times

Calculate the programmed flight event times based on the allocated PTL. Because the PTL relates to the ADES the following table shows this process in reverse order :

Substitute Sheet Step Action

5 Calculate the ADEP programmed gate departure time

Calculating the GATP

To calculate the GATP, CTMS performs a number of steps as shown in the following step action table:

Determining the ADES Terminal

The ADES passenger terminal is obtained by searching the passenger terminal table for entries matching the airline operator for the flight, weather the Domestic or International terminal is to be used.

If the airline operator is not directly associated with a particular terminal building, then the database will be checked to see if the operator is represented by or hosted by another airline (at that ADES). If so, the other airlines details will be used. If not, then the default terminal for the aiφort will be assumed.

ute Sheet

Determining the ADES GNDMI

The ADES GNDMI is obtained by searching the ground manoeuvring table for an entry matching the ADES, the ADES RWY (from the ADES TAMP), the ADES passenger terminal and the aircraft category for the flight.

Calculating the GATP

The GATP for each flight is the allocated PTL plus the ADES GNDMI.

Calculating the TOFP

The TOFP for each flight is the allocated PTL minus the ADES TMAMI.

Calculating the ETDP

The ETDP for each flight is the TOFP minus the ETF.

e Sheet Calculating the TOTP

The TOTP for each flight is the ETDP minus the ADEP TMAMI.

Calculating the GATP

The GATP for each flight is the TOTP minus the ADEP GNDMI.

Default data in Programmed Time Calculations

When the event times are recalculated for a flight from a non-CTMS aiφort, or for a CTMS aiφort for which no TAMP has been loaded, the process will be similar to that described above except that default data (not obtained from an active TAMP) will be used.

TAMP Amendments

Whenever a new active TAMP quartile for a CTMS aiφort that involves a change to the aiφort configuration for arrivals and/or departures, a change in the arrival acceptance rate and/or type of approach is registered, CTMS:

• Re-calculates the PTLs for the CTMS aiφort(s) affected

• Re-performs the allocation of PTLs as detailed above in this map

• Recalculates event times for all flights based on the new PTL's.

However movements scheduled within 2 hours of the time that the change is made will be unaffected reflecting the reaction time required by the airlines.

Addition of new Flights

The addition of new flights will not disrupt PTLs allocated via the bulk programming already performed. New flights will be fitted into the arrival sequence for each CTMS aiφort as the availability of PTLs permits.

Examine Flight Options Function

The examine flight options function permits users to evaluate the feasibility of conducting an unscheduled or newly scheduled flight to a CTMS aiφort.

The Examine Flight Options Function also permits interactive users to enter details of a proposed flight or to revise details for an existing flight. When the flight details are entered, the CTMS will run the flight programming function to calculate the ETL for that flight and

Substitute Sheet determine the nearest available PTL which is on or after the ETL. This PTL is displayed to the user together with other PTLs which are available for allocation to the flight.

The user then has the ability to reserve a PTL for the proposed flight, by FLT NO, for a period determined by agreement within the CCB.

Registration of Itinerant Flight Function

The registration of itinerant flight function permit ATS users to register a new scheduled flight.

Register Flight Itinerant Function

The operation of the register itinerant flight function is similar to the examine flight options function.

Newly registered flights are simply added to the bulk schedule and the Flight Programming Function run for this flight only.

Itinerant flights advised prior to bulk programming will be included in the 'bulk programming'. Itinerant flights advised after bulk programming will be allocated a PTL without disrupting existing allocations.

Flight Progress Monitoring

The Flight Progress Monitoring Function is provided to assist airlines to get an improved view of what is happening to the progress of their flights.

The elements of flight progress monitoring allows:

• The receipt and processing of actual aircraft movement messages

• Monitoring of designated fixes and aiφorts

Aircraft movement messages that permit CTMS to monitor the progress of flights are as follows:

Gate departure messages

Take off messages

Departure or ATD messages

Landing messages

Gate arrival messages

TAAATS system messages

stitute Sheet Flight Progress Monitoring Function

Flight following commences when CTMS receives advice of an aircraft push back from its departure gate at a CTMS aerodrome or setting course from a non-CTMS aerodrome.

Accurate Arrival Information

TAAATS data is provided to update ETL and GAT.

Monitoring of Designated Fixes

The designated fix display function permits users to sort and display snapshot lists of flights over designated fixes and aiφorts in chronological order. It also permits counts of flights over designated fixes and aiφorts together with the ability to make projections.

It will also allow airlines to view current and projected TAMPs for CTMS aiφorts.

Receipt of Gate Departure Time

Upon receipt of a gate departure time from a suitably equipped aircraft or aiφort operator the CTMS shall change the flight status from planned to Active, store this time in the Actual Gate Departure Time (GDTA) field and extrapolate the :

TOTE

ETDE

TOFE

ETLE

GATE

Receipt of a Take-Off Time

Upon receipt of a take off advice from a suitably equipped aircraft or aiφort operator, the CTMS shall store this time in the actual take off time (TOFA) field and re-extrapolate the:

ETDE

TOFE

ETLE

GATE

Substitute Sheet Receipt of a DEP Message or Actual Time of Departure

Upon receipt of a DEP or other departure advice from a suitable equipped aircraft or aiφort operator, the CTMS shall store this time in the ATD field and re-extrapolate the:

TOFE

ETLE

GATE

Receipt of a Landing Time

Upon receipt of a landing time from a suitably equipped aircraft or aiφort operator, the CTMS shall store this time in the ATL field and re-extrapolate the Gate Arrival Time (GATE).

Receipt of an Actual Gate Arrival Time

Upon receipt of a Gate Arrival Time from a suitably equipped aircraft or aiφort operator, the CTMS shall store this time in the Actual Gate Arrival Time (GATA) field and change the flight status from Active to Complete.

Receipt of TAAATS System Messages

When a TAAATS STAR is generated for a flight inbound to a CTMS aiφort, the system shall update the ETL and extrapolate a new GAT from that ETL and the taxi time for the nominated runway.

Other Reporting Functions

CTMS can also provide the capability to produce additional reports for users in real time. These reports represent a snapshot at the time of generation and automatic update will not be supported.

Reports for ATC

ATC shall be able to generate reports for ATC users. These reports will include:

• Sort and display flights over designated fixes and aiφorts.

• "What if scenarios involving different aiφort arrival acceptance rates.

• The approval program including PTL's not allocated.

• Possible airborne and surrounding delay reports.

Substitute Sheet Reports for Industry

Major airlines can be provided with a total view of the database excluding details of flights not under their direct operational control, or an affiliated airline.

Minor airlines and ad hoc operations will be permitted to view the following reports over a secure Internet site:

• Their approved program including PTL not allocated, and the functionality to amend these programs

• Aiφort TAMPs

The foregoing describes embodiments of the present invention and modifications, obvious to those skilled in the art can be made thereto, without departing from the scope of the present invention.

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Claims

1. A method for scheduling the flow of air traffic into a destination aiφort over a particular time period, the method including the steps of:

(a) establishing an arrival schedule over the particular time period at said destination aiφort for a plurality of aircraft;

(b) determining prior to the particular time period, the departure aiφorts from which each of said aircraft departs, so as to define a travel path from a departure aiφort to the destination aiφort for each aircraft;

(i) aircraft type;

(v) time taken by an arriving aircraft from passing over the designated route fix, to land on the specified landing runway of the destination aiφort;

(vii) flight path;

(viii) weather conditions; or

(ix) any other travel time influencing factor;

Substitute Sheet (e) establishing an initial total estimated travel time for each aircraft by summing the respective travel sequence times for each aircraft;

2. A method according to claim 1, further including the step of:

(g) monitoring the variable conditions so as to be appraised of when the total estimated travel time for one or more aircraft is likely to vary from said initial total estimated travel time.

3. A method according to claim 2, further including the step of:

4. A method according to any one of the preceding claims, wherein the variable conditions are monitored in real time.

5. A method according to any one of the preceding claims, wherein the historical data is calculated from empirical data and retrieved from a database.

6. A method according to any one of the preceding claims, wherein the plurality of aircraft are operated by a plurality of airline operators.

7. A method according to any one of the preceding claims, wherein the particular time period is a 24 hour period of time.

8. A method according to any one of the preceding claims, wherein the time period is broken into daily time quartiles of 6 hour periods each.

9. A method according to any one of the preceding claims, wherein a programmed time of landing is calculated from the estimated arrival schedule for each aircraft.

10. A method according to any one of claims 2 to 9, wherein the variable conditions further include any one or more of the following variables:

(a) delays of a flight;

(b) notifications of newly scheduled and re-scheduled flights;

(c) amendment of a terminal area management plan; or

s itute Sheet (d) flight cancellations.

1 1. A system to schedule the flow of air traffic into a destination aiφort over a particular time period including: an aircraft arrival schedule means adapted to establish record an arrival schedule over the particular time period at said destination aiφort for a plurality of aircraft, said aircraft arrival schedule means capable of determining prior to the particular time period, the departure aiφorts from which each of said aircraft departs, so as to define a travel path from a departure aiφort to the destination aiφort for each aircraft and wherein the travel path of each aircraft is divided into a plurality of travel sequences; data base means adapted to estimate from historical data, an initial time estimate for each travel sequence, said initial time estimate being dependent upon any one or more of the following variables:

(i) aircraft type;

(v) time taken by an arriving aircraft from passing over the designated route fix. to land on the specified landing runway of the destination aiφort;

(vi) time taken for an arriving aircraft to taxi from the specified landing runway to its gate or its parking position:

(vii) flight path;

(viii) weather conditions; or

(ix) any other travel time influencing factor; and

Substitute Sheet wherein the aircraft arrival schedule means is further adapted to establish an initial total estimated travel time for each aircraft by summing the respective travel sequence times for each aircraft, and to sequence the departure time of each aircraft in accordance with the initial total estimated travel time, so that the time of aircraft arrival is estimated and an arrival schedule is established.

12. A system according to claim 1 1, wherein the aircraft arrival schedule means monitors the variable conditions so as to be appraised of when the total estimated travel time for one or more aircraft is likely to vary from said initial total estimated travel time.

13. A system according to claim 12, wherein the aircraft arrival schedule means allows amendment of the departure times of any of the aircraft for which the total estimated travel time has been varied so that the aircraft arrive in substantial accordance with the arrival schedule.

14. A system according to any one of claims 1 1 to 13, wherein the variable conditions are monitored in real time.

15. A system according to any one claims 1 1 to 14, wherein the historical data recorded in the data base means is calculated from empirical data and retrieved from a database.

16. A system according to any one claims 1 1 to 15, wherein the plurality of aircraft are operated by a plurality of airline operators.

17. A system according to any one of claims 1 1 to 16, wherein the particular time period is a 24 hour period of time.

18. A system according to any one of claims 1 1 to 17, wherein the time period is broken into daily time quartiles of 6 hour periods each.

19. A system according to any one of claims 11 to 18, wherein a programmed time of landing is calculated from the estimated arrival schedule for each aircraft.

20. A system according to any one of claims 12 to 19, wherein the variable conditions further include any one or more of the following variables:

(a) delays of a flight;

(b) notifications of newly scheduled and re-scheduled flights;

(c) amendment of a terminal area management plan; or flight cancellations.

Substitute Sheet

21. A method for scheduling the flow of air traffic into a destination aiφort over a particular time period, substantially as hereinbefore described with reference to the examples disclosed herein.

22. A system to scheduling the flow of air traffic into a destination aiφort over a particular time period, substantially as hereinbefore described with reference to the examples disclosed herein.

Substitute Sheet