Chapter 12: Airport Capacity and Delay

Overview

• Discusses the concepts of airport capacity and delay management.

Capacity

Definition

• Capacity: Practical maximum number of operations that a system can manage in a given time.

  • Measured in aircraft operations per hour.

Passenger Processing Capacity

• Number of passengers efficiently processed through the terminal in a given time.

  • Example: 428 passengers per hour.

Throughput

• Throughput: Ultimate rate of aircraft operations that can be handled without considering minor delays due to operational imperfections or small random events that might occur

Practical Capacity

• Practical Capacity: Number of operations accommodated over time with a nominal amount of delay.

FAA Capacity Measures

• Practical Hourly Capacity (PHOCAP)

• Practical Annual Capacity (PANCAP)

• These are measured as the number of operations that may be handled resulting in not more than 4 minutes average delay during the busiest (peak) 2 hour operating period hourly and annually

Factors Affecting Capacity and Delay

Variability Influences

1. Use of runways.

2. Type of aircraft operating.

3. Percentage of takeoff and landing operations.

4. Climatic conditions.

5. FAA regulations on runway use.

6. Layout of runway, taxiway, and apron environment (p. 430).

Additional Influences

• Instrument Landing Systems (ILS) presence.

• Runway configurations:

  • Single runway.

  • Parallel runways (greater capacity).

  • Open-V runways.

  • Intersecting runways.

• Capacity is generally greater in Visual Meteorological Conditions (VMC) compared to Instrument Meteorological Conditions (IMC)

Runway Configuration

Types of Configuration

• Parallel Runways:

  • Capacity varies based on separation:

    • —> 4,300’

      • Independent simultaneous

    • >2,500’

      • Dependent simultaneous

    • <2,500’

      • Single runway

• Single Runway:

  • Operates under specific conditions.

• Open-V Runways:

  • Configuration for specialized operations.

• Intersecting Runways:

  • Capacity depends on traffic management strategies.

• Under certain conditions aircraft may land and hold short (LAHSO) of intersecting runways

Estimating Capacity

• When a runway is constantly occupied, it is operating at capacity

• Based on:

  1. Type of aircraft.

  2. Runway Occupancy Time (ROT):

     • Shorter ROT leads to greater capacity

Departure Capacity

• Impacted by time to roll and rotate

Arrival Capacity

• Affected by approach speeds and longitudinal separation, which is influenced by wake turbulence

Defining Delay

Delay Dynamics

• Delay: The duration between the desired time for an operation to occur and actual time of occurrence

Causes of Delay

• Mechanical issues.

• Luggage handling.

• Weather conditions.

• Scheduling conflicts with other aircraft (p. 446).

Approaches to Reducing Delay

Strategies

1. Increase system capacity.

2. Manage system demand (p. 451).

Creating New Infrastructure

Important Developments

• DIA Completion (1995): Significantly reduced delays at a cost of over $5 billion.

  • Challenges in financing and constructing new infrastructure due to:

    • Community development.

    • Environmental concerns.

    • Property and funding shortages.

    • Lack of public support.

    • Rival interests (p. 452).

Projects Timeline

• January 1997 – October 2002:

  • Developed 7 new runways and 19 capacity projects including 15 runway extensions.

  • Planned 39 additional projects (2002-2007), including 13 new runways.

• Increased taxiway placements help reduce ROT (p. 452).

Converting Military Airfields

Transition to Civil Use

• Downsizing military in the 1990s led to increased capacity from military airfield conversions.

• Military airfields designed for heavy aircraft, examples include Bergstrom AFB, Austin, TX, replacing smaller airports (p. 453).

Administrative and Demand Management

Regulatory Strategies

1. Administrative Management: Airport authority allocates airport access by setting quotas on passenger enplanements or on the number and type of aircraft operations

2. Economic Management: Structure pricing so that market forces allocate scarce airport facilities

• Demand management does not increase capacity rather promotes more effective or economically efficient use of facilities

Traffic Diversion

• Diverting traffic to underused airports is recommended.

• General Aviation (GA) traffic contributes 10-20% of operations at large commercial service airports (p. 455).

Quotas or Slots

• an administratively established limit on the number of operations per hour

• Because delay increases exponentially as demand approaches capacity, a small reduction in the number of hourly operations can have a significant effect on delay

Operational Limits

• Quotas limit operations per hour to reduce delays when demand approaches capacity

Demand Management

Economic Approaches

• Relies on price mechanism and is favored by economists

• Economists suggest that by including costs and demand as determinants of user fees, delay can be significantly reduced.

• Leverages price mechanisms to manage demand and advocate for delay reduction through:

  1. Differential pricing

  2. Auctioning of landing rights

Continued Economic Focus

• Emphasis on using economic strategies for managing demand persists (p. 459).