F2.1 CAPACITY MEASUREMENT OVERVIEW
Capacity measurements vary from one subsystem to another. The term capacity has many definitions,
but it generally makes reference to a limit, when reached or exceeded, which affects an airport's operations and level of service.
Capacity is often use to describe the variable measurement of a specific airport system or subsystem's
throughput, or the system's capability to accommodate a designated level of demand. Comprehensive
capacity assessments are based on five fundamental measurements, noted in the following sub- headings.
F2.1.1 Dynamic Capacity
Dynamic Capacity refers to the maximum processing or flow rate of persons (i.e. occupants)
F2.1.2 Static Capacity
Static Capacity is used to describe the storage potential of a facility or area, and is usually expressed
as the number of occupants that a given area will accommodate at any one moment. It is a function of the total useable space available and the level of service to be provided; i.e., the amount of space each occupant may occupy. Static capacity standards are stated as square meters per occupant (m2/occ.) for each level of service.
F2.1.3 Sustained Capacity
Sustained Capacity is used to describe the overall capacity of a subsystem to accommodate traffic demand, over a sustained period within the space and time standards of a particular level of service. It is thus a measure of the combined dynamic and static capacities of the processors, reservoirs and links. IATA recommends using level of service C to determine the sustainable capacity. The definition
for level of service C is shown in section F9.1.2.
F2.1.4 Maximum Capacity
Maximum Capacity refers to the maximum traffic flow which can be achieved for the chosen time unit only, but not sustained for a longer period, in accordance with safety requirements and regardless
of delay or level of service.
F2.1.5 Declared Capacity
Declared Capacity refers to site specific limiting capacities, in numeric terms, of individual facilities and resources. These capacities are forwarded to the appropriate bodies to be used in the preparation
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SECTION F3: AIRPORT SYSTEMS F3.1 AIRPORT SYSTEMS OVERVIEW
An airport is more than a large paved area, a set of plans or an architectural concept. An airport should be seen and planned as a dynamic system that handles the flow of pedestrians, vehicles, aircraft, baggage, cargo and mail. The passengers, baggage, greeters & well-wishers, vehicles and aircraft must pass through inter-related systems to be queued, processed and circulated on various links such as taxiways, corridors, escalators, etc.
F3.1.1 Airport Facilities/Systems
Airport facilities should be planned according to the following principles:
•
Airports should be developed to operate in an efficient manner, taking into account the safety ofthe users and clients.
•
Aircraft flows should be designed to operate with maximum efficiency across the airside sub systems; i.e. the gate, apron, taxiways, runways, and airspace.•
Passenger flows should be designed to minimize inconvenience and confusion as passengers proceed through the network of terminal subsystems.•
Baggage systems should be designed to provide an efficient, fast, reliable and cost-effective flowof hold baggage from check-in to aircraft, from aircraft to aircraft, and from aircraft to baggage reclamation. See chapter U for information on Baggage Handling Systems (BHS).
•
Vehicular flows should be designed to provide an efficient and reliable access/egress to the terminal facilities.•
The passenger terminal building should be designed to provide an efficient and seamless flow between the landside and airside elements.•
Airports should be designed to offer a balanced flow through the interface points of the system.•
Each system should be flexible enough to accommodate future requirements in order to maintainthe balance of the overall airport system.
An airport can be subdivided into several main, interrelated systems. The airside network has a larger
space requirement, while the terminal building represents the transfer portion of the overall system through which passengers move from their ground access modes to the apron, vice versa, or alternately
between flights.
The ground access/terminal building transition point is at the curb, while the apron/terminal building transition point occurs at the bridge/gate. These transition or interface points between the systems mark the points where the nature of the flow changes. In the deplaning process, for example,
This relationship is shown in the following schematic diagram:
J
_L
J
Arriving Vehicles Occupants
I
Aircraft Deplaning
I
Departing Vehicles Occupants Aircraft Deplaning
F3.1.2 Capacity Balance
A primary objective of the planning process is to find the correct, balanced capacity and level of service between facilities, operations, rules & procedures and airline schedules. Balancing capacity is primarily required to avoid displacing a bottleneck to another critical facility. It often means ensuring
the terminal, gate and apron systems do not limit the runway throughput. Six major system studies are considered when balancing capacity and determining the reliable throughput of the airport. These
being:
Terminal Airspace
Terminal airspace studies are undertaken to determine when existing capacity and limiting factors
require improvement prior to considering investment in new facilities. The maximum reliable terminal airspace throughput for landings and departures is determined separately.
Runway/Taxiway
A runway capacity study is undertaken to determine the exiting and maximum reliable runway capacity. The runway system is a critical component to the overall system, and runway capacity ultimately determines a given airport's maximum capacity. Every effort should be made to ensure
that other airport facilities are not limiting runway throughput and performance.
Apron
Simulation is often required to ensure that the apron acts as an effective link between the gate and the runway systems and does not become a bottleneck.
Gate
The number of stands and aircraft parking positions for different types/sizes of aircraft is calculated
to meet the current and future year requirements up to the ultimate runway capacity. This, information is essential to develop realistic and cost-effective airport concepts.
Passenger Terminal
The number of counters/processors, a building's reservoir (holding) potential, levels of service, and requirements by facility or area are calculated for the passenger and greeter/well-wisher flows for the passenger terminal.
Enplaning passengers must pass through some or all of a series of subsystems, while deplaning
passengers must pass through some or all of a separate series. In some cases, the same subsystems are used by both flows. Additionally transfer passengers must be considered since they utilize some of the subsystems of both passenger flows. In the case of 'hub' airports, the volume of transfer passengers may be very significant. Passenger terminals also process
international
passenger flow, in order to properly analyse passenger terminals. The passenger flow routes should be flexible and should:
• Be as short and straight as possible, unimpeded by obstructions from cross-flows or Be capable of use by all airlines and not restricted to individual aircraft loads. Govern control positions in order to avoid bottlenecks.
Be sufficiently flexible to permit the establishment of temporary channels which can be used as by-pass routes by other passengers (e.g., for individual health control processing of a particular arriving aircraft passenger load) or to permit regulation evolution.
Permit processing of passengers individually or in groups. Introduce a minimum number of level changes.
Allow flow separations for government regulations or security reasons.
Provide one flow route for departing domestic passengers and one for international passengers.
One flow route for arriving domestic passengers and one for international passengers. Separate departing passengers from those arriving after security check-points.
F3.2 IATA RECOMMENDATIONS
F3.2 IR1 Airport as a Dynamic System
An airport should be seen and planned as a dynamic system that handles flow of pedestrians, vehicles, aircraft and baggage going through inter-related systems.
F3.2 IR2 Airport Facilities
Airports in general should be planned in accordance with the principles defined within Clause
F3.1.1. ~
F3.2 IR3 Balancing Capacity
Balancing capacity is required to avoid displacing a bottleneck to another critical facility considering runway capacity ultimately determines the maximum capacity of an airport.
F3.2 IR4 Passenger Flow