FACT3: Airport Capacity Needs

in the National Airspace System

January 2015
FROM THE ADMINISTRATOR 

Dear Members of the Aviation Community: 

This is the third iteration of the Federal Aviation 

Administration’s (FAA) long-term outlook for airport 

capacity in the United States. Like the previous 

studies, the primary goal is to identify airports that 

are likely to need more capacity to accommodate 

anticipated growth in demand. 

Today, most hub airports in the United States 

operate efficiently with moderate delays. This is a 

significant improvement from prior editions of the 

Future Airport Capacity Task (FACT) reports when 

delays at many airports were growing and causing a 

ripple effect of systemwide delays. The graphic on the following page helps illustrate 

the substantial reductions in congestion that have been achieved during the 10 years 

since the first FACT report was published. 

Working closely with airports, we’ve been able to dramatically enhance capacity at 

many airports. This report shows the combined effects of adding 18 new runways

and seven extended runways at 21 busy hub airports since 2000. That’s a

tremendous amount of new capacity that allows traffic to flow more freely in and out 

of airports to better serve their communities and the nationwide system. At other 

airports, air traffic has decreased with structural changes in the airline industry. As a 

result of both enhanced capacity and traffic changes, congestion has been reduced 

and the nationwide system is more reliable. Bad weather days have less impact, and 

we can recover schedules faster once the weather clears. 

Since the publication of the second FACT report in 2007, the aviation industry has 

continued to evolve, and we’ve sought to keep pace with ongoing trends in this 

report. Our data and modeling of future demand, fleet mix, throughput, air traffic 

control (ATC) procedures, and NextGen have all been updated. We’ve also included 

surface components to better gauge congestion that can occur on the airport surface 

and at gates. 

What have we learned? Most (but not all) of our hub airports will be able to function 

well in terms of capacity through the next decade. NextGen is helping to manage 

delays resulting from increasing congestion at many airports, but NextGen alone 

cannot create sufficient additional capacity at some of the largest and busiest 

airports. This is not surprising, as FAA has always acknowledged that new runways 

and other solutions will still be necessary to address traffic growth and reduce delays. 

Therefore, we still have work to do. It’s vital that active airfield work continue at key 

hubs like Chicago O’Hare and Philadelphia International Airports if we are to keep 

pace with demand and stay ahead of delays. While capacity and delays have 

improved nationally, there are a handful of airports with consistent delays – most 

notably John F. Kennedy, LaGuardia, Newark, Philadelphia, and in the coming years, 

San Francisco. Airline scheduling is increasingly concentrated at major hubs, which 

has exacerbated congestion as well. While NextGen will improve performance, it’s 

likely that significant congestion will continue to plague these airports unless 

additional airfield capacity enhancements can be achieved. The FAA is committed to 
supporting continued work in these locations to evaluate and implement effective 

long-term solutions in collaboration with stakeholders. 

Looking further into the future, out to 2030, this report will also show that with 

cumulative traffic growth, more hub airports will become congested. However, due to 

aviation industry consolidation and other factors, there is uncertainty with these 

longer-term projections. For example, the airlines may accelerate the current trend 

in upgauging to larger aircraft, flying more passengers on fewer flights. With these 

short-range fluctuations, it's chal lenging to determine when long-term capacity 

enhancements will be needed. Nonetheless, this long-term outlook warrants careful 

monitoring and continuing airport planning efforts in order to stay ahead of 

congestion and delay as the economy improves and air travel demand picks up. 

Where do we go from here? Principally, the findings of this report underscore the 

continued need for investment in aviation infrastructure. The airports identified in 

this report need to continue progress on their runway projects and other airfield 

enhancements, while FAA and our industry partners need to continue the push 

forward with NextGen. Both airport development and NextGen are complementary of 

course. Together, they enable efficient, reliable access to the safest and most 

dynamic aviation system in the world. 

t:iC:ft:tV 

FAA Administrator 
FACT1 FACT2 FACT3

Airport 2004 2013 2020 2007 2015 2025 2011 2020 2030

ABQ

ATL

BDL

BHM

BOS

BUR

BWI

CLT

CVG

DCA

DEN

DFW

DTW

EWR

FLL

HOU

IAD

IAH

ISP

JFK

LAS

LAX

LGA

LGB

MDW

MEM

MIA

MSP

OAK

ONT

ORD

PBI

PHL

PHX

PVD

SAN

SAT

SEA

SFO

SLC

SNA

STL

TUS

Comparative 

Summary Results 

Across

all Three 

FACT Reports

Legend:

Constrained in 

reference case, but 

unconstrained if 

planned 

improvements are 

implemented

Constrained even 

after all planned 

improvements are 

implemented; 

additional capacity 

enhancement is 

needed; or 

constrained in base 

year.

No symbol indicates not 

capacity constrained

Note: This table lists only 

the airports that were 

identified as capacityconstrained in one of the 

FACT reports. Other 

airports that were 

analyzed in the FACT 

reports, but not identified 

as capacity-constrained, 

are not included. 
FACT3: Airport Capacity Needs in the National Airspace System

Page i January 2015

TABLE OF CONTENTS

SUMMARY INTRODUCTION............................................................................................1

Airport Capacity Constraints and Congestion through 2020....................................................2

What is expected by 2030?..................................................................................................3

NAS Modernization: NextGen and New Runways..................................................................3

Recommendations ..............................................................................................................4

METHODOLOGY AND INPUTS – WHAT HAS CHANGED SINCE FACT2? ..........................5

Updated Forecast and Fleet Mix Data ...................................................................................5

Planned Improvements: Runways, NextGen, and NAS Modernization ....................................7

Airport Selection ...............................................................................................................10

Models and Identification Criteria.......................................................................................10

Airport Capacity Profiles and ASV Studies ...........................................................................11

COORDINATION WITH AFFECTED AIRPORTS..............................................................12

FINDINGS OF THE FACT3 REPORT...............................................................................12

Congested Airports in 2011................................................................................................13

Interim Capacity Needs in 2020 .........................................................................................14

Needed Capacity Beyond What is Currently Planned for 2020 ...................................................... 17

Airport Capacity Improvements by 2020 .................................................................................... 17

Long-Term Capacity Needs in 2030....................................................................................18

Needed Capacity Beyond What is Currently Planned for 2030 ...................................................... 19

Airports Capacity Improvements by 2030................................................................................... 21

Airports With Some Congestion to be Monitored .................................................................21

CONCLUSIONS AND RECOMMENDATIONS ..................................................................22

APPENDIX A: STUDY AIRPORTS ............................................................................... A-1

APPENDIX B: METHODOLOGY................................................................................... B-1

Introduction ................................................................................................................... B-1

Study Scope and Scenarios.............................................................................................. B-1

Airport Selection ............................................................................................................. B-1

Demand ......................................................................................................................... B-3

Refined and Expanded Methodology................................................................................. B-3

Modeling ........................................................................................................................ B-4

Annual Service Volume............................................................................................................ B-4

NAS-Wide Modeling ................................................................................................................ B-4

Identification Criteria....................................................................................................... B-6
FACT3: Airport Capacity Needs in the National Airspace System

Page ii January 2015

APPENDIX C: COMPARISON OF FACT1/2/3 METHODOLOGIES................................ C-1

APPENDIX D: SENSITIVITY ANALYSIS OF THE 2013 TAF ON FACT3 RESULTS ........ D-1

Overview of the 2013 TAF ............................................................................................... D-1

Methodology for Estimating Effect of Demand Changes on FACT3 Results .......................... D-2

Potential Effect of the 2013 TAF....................................................................................... D-3

2020 Reference Scenario.........................................................................................................D-4

2020 Improvements Scenario ..................................................................................................D-4

2030 Reference Scenario.........................................................................................................D-5

2030 Improvements Scenario ..................................................................................................D-5

LIST OF FIGURES

Figure 1. Actual and Forecasted Annual Operations at 30 Core Airports..................6

Figure 2. FACT3 Scenarios in 2020 and 2030 ......................................................8

Figure 3. Airports Needing Capacity Today (2011) .............................................14

Figure 4. Airports Needing Additional Capacity in 2020 ......................................16

Figure 5. Airports Needing Additional Capacity in 2030 ......................................20

LIST OF TABLES

Table 1. Airports Needing Additional Capacity in 2020........................................15

Table 2. Capacity Enhancement and Congestion Reduction in 2020 .....................18

Table 3. Airports Needing Additional Capacity in 2030........................................19

Table 4. Capacity Enhancement and Congestion Reduction in 2030 .....................21

Table 5. Airports With Some Congestion to be Monitored....................................22
FACT3: Airport Capacity Needs in the National Airspace System

Page 1 January 2015

SUMMARY INTRODUCTION

In 2003, FAA convened a team to assess the Nation’s future airport capacity needs. This 

effort, which became known as the Future Airport Capacity Task (FACT), represents a 

strategic approach to identify the airports that have the greatest need for additional 

capacity in the future. The identification is based on a macro-level analysis of the factors 

and trends contributing to congestion and delay at the busiest airports in the Nation. By 

embarking on this initiative, FAA seeks to ensure that the long-term capacity of the 

U.S. aviation system can adequately serve future demand.

The team is led by the Office of Airports (ARP) and includes active participation from the 

Air Traffic Organization (ATO) Capacity Analysis Group and the MITRE Corporation’s Center 

for Advanced Aviation System Development (CAASD). The FAA’s Office of Aviation Policy 

and Plans (APO) and the NextGen office (ANG) are also involved in the conduct of the 

studies.

The first report in the series, commonly known as FACT1, was published in 2004 and 

identified shortfalls in the system through 2020. This study was the first top-down review 

of the busiest commercial service airports in the Nation. The report’s findings supported the 

need for a substantial number of major airport capacity projects nationwide. After 

considering all planned improvements at the time, 18 airports were projected as needing 

additional capacity by 2020.

An updated report, FACT2, was published in 2007 to identify shortfalls through 2025. 

FACT2 included a more transparent methodology and refined analytical methods. Fourteen 

busy hub airports located in the Nation’s most populated regions (such as the Northeast 

Corridor and California coast) were projected to be capacity-constrained in 2025 even with 

completion of all planned improvements, as then contemplated. Notably, the report also 

reaffirmed that key runway projects would allow several hub airports to reduce delays and 

continue growing; this supported the completion of five new runways that have been 

commissioned at hub airports since the report’s publication. The report provided an initial 

look at capacity benefits from the Next Generation air traffic control (ATC) system, better 

known as NextGen. The FAA’s investment in NextGen began in 2007. The graphic following 

the Administrator’s letter provides a comparison of the FACT1, 2, and 3 report results.

All of the FACT reports have begun with a broad sampling of several hundred commercial 

service and busy general aviation airports nationwide. From this initial step, a smaller 

number of airports are identified for more detailed study. Both FACT1 and FACT2 evaluated 

capacity and delay at 56 airports, including the 35 airports that were part of the now

completed Operational Evolution Plan (OEP). FACT3 conducted a more detailed evaluation 

of 48 airports, including the 30 Core airports that FAA currently tracks as a measure of 

system performance in the National Airspace System (NAS).

Since the publication of FACT2, the aviation industry in the United States has continued to 

rapidly evolve. Due to the Great Recession and volatile (often higher) fuel costs, airlines 

have emphasized better ticket yields, fees, and load factors, rather than improved market 

share as a strategy for profitability. Airlines have consolidated through mergers and have 

increasingly focused their connecting operations at major hubs. While the use of 50-seat 

regional jets (RJ) has grown substantially during the last decade, these aircraft are now 

leaving the fleet due to their higher fuel costs and upcoming major maintenance cycles. 

Airlines are replacing these smaller RJs with larger RJs and narrow-body aircraft, enabling 
FACT3: Airport Capacity Needs in the National Airspace System

Page 2 January 2015 

airlines to accommodate passenger growth but with fewer operations. Collectively, these 

factors have resulted in relatively flat traffic growth over the last few years. As a result, the 

FAA forecast estimates 32 percent fewer operations and about 23 percent fewer

enplanements in 2025 at the 30 Core airports than the forecast used in FACT2. 

FACT3 is scoped to incorporate many of these trends through 2020 and 2030. In addition 

to updated forecasts, the FACT3 analysis includes current aircraft fleet mix projections, 

updated NextGen planning (which has matured substantially since 2007), and modeling of 

gate and surface constraints on airport capacity. 

The FACT3 assessment relies on a similar systemwide modeling approach as that used by 

FAA to estimate the midterm benefits of NextGen, as well as the same airport capacity 

assumptions and air traffic projections. Thus, the FACT3 results are consistent with the 

overall delay reduction benefits reported in the Business Case for NextGen. Where FACT3 

differs is in the use of location-specific metrics (e.g., percent of congested operating hours 

above a delay threshold) that describe future congestion levels at airports. FACT3 also 

incorporates a near-term NextGen scenario that reflects only the specific capabilities that 

are ready and expected to be widely deployed in the NAS within the next few years. In 

contrast, the analytical results reported in the Business Case for NextGen reflect all of the 

midterm NextGen capabilities to calculate total system wide delay savings. While the 

Business Case quantifies total NextGen benefits for the entire NAS, FACT3 is meant to 

provide airport-specific results that can inform local infrastructure planning discussions. 

In brief, the FACT3 report findings support the following: 

Airport Capacity Constraints and Congestion through 2020

• Today delays are concentrated at a few major hub airports, which reflect ongoing trends

towards airline consolidation at their hubs. The New York City (NYC) area airports,

Philadelphia International Airport (PHL), and Hartsfield-Jackson Atlanta International

Airport (ATL) have significant congestion.1

• The NYC area airports (Newark Liberty International (EWR), John F. Kennedy

International (JFK), and La Guardia (LGA)) will continue to have significant capacity

constraints through 2020; LGA and JFK delays are expected to worsen such that

congestion will become severe.2

• At ATL, the new runway that opened in 2006 and area navigation (RNAV) flight

procedures have improved the airport’s capacity; however, the airport remains prone to

delays due to demand growth and arrival/departure banks in the schedule of the

airport’s primary airlines. Delays at ATL are projected to continue to grow through

2020. However, the use of larger aircraft by the airport’s primary airlines and/or a more

balanced flight schedule could mitigate these delay projections.

1This report identifies airports with their three-letter FAA location identifiers. For a complete list, see Appendix A. 

2At the NYC area airports, the FAA forecast assumes unconstrained operations demand growth at JFK and EWR and 

constrained growth at LGA. Since FACT3 uses the Terminal Area Forecast (TAF), the additional congestion 

projected is a reflection of demand growth above the existing schedule limits. Should the schedule limits continue 

(due to future regulatory action), there will be less congestion than this report projects. 
FACT3: Airport Capacity Needs in the National Airspace System

Page 3 January 2015 

 When implemented at San Francisco International Airport (SFO), midterm NextGen

capabilities will be sufficient to reduce delays below the significance criteria due to more

efficient flight procedures. Without midterm NextGen, SFO is projected to be capacityconstrained in 2020.3

• The planned runway extensions at PHL will serve to reduce average arrival delays,

although the airport is projected to remain significantly congested if the planned new

parallel river runway is not constructed.

What is expected by 2030? 

• The 2030 scenarios show that with steady traffic growth as forecasted, delays will

continue to grow. Without planned improvements beyond near-term NextGen,

12 airports will have significant congestion, including 11 that will have severe congestion

as shown in Table 3 and Figure 5.

 The implementation of midterm NextGen capabilities is expected to reduce growth in

delays at the capacity-constrained airports by about 26 percent, with a slight increase in

total throughput of up to 2 percent. This is as compared to the 2030 Reference Scenario

(i.e., no further improvements beyond near-term NextGen). Although this is a

worthwhile improvement, the congestion reduction is not sufficient to keep these

airports below the FACT3 significance criteria.

• Of particular note, the runway development projects (both ongoing and future phases)

at Fort Lauderdale/Hollywood International Airport (FLL), Chicago O’Hare International

Airport (ORD), and PHL provide sufficient capacity to keep these airports from becoming

severely congested by 2030.

NAS Modernization: NextGen and New Runways 

• Many of the NextGen capabilities provide incremental benefits – a moderate throughput

increase, or the ability to fly more efficient routes, or optimized descents that save fuel.

Time-based metering can optimize traffic flow into an airport. Surface metering

methods and decision support tools allow for improved data sharing and coordination.

This reduces capacity losses that would otherwise occur during certain adverse

conditions. These capabilities are important as they improve the efficiency,

predictability, and reliability of the entire NAS. Still, if an airport is facing a substantial

shortfall in capacity, the best answer is often new pavement. The optimal combination

of solutions in each particular location depends on the scale of the capacity/demand

imbalance and the specific operational issues that need to be addressed. Often, at

congested airports, both are necessary to foster improved operational performance. For

example, NextGen improvements may be needed to maximize the capacity benefits of a

new runway.

3Currently, SFO is designated by FAA as Level 2 under the International Air Transport Association Worldwide Slot 

Guidelines. Level 2 indicates that there is a potential for congestion that could be managed by voluntary means. 

This designation is necessary due to runway capacity, existing congestion and delays, and expected increased 

congestion with multiyear airport construction projects. The FAA is working with airlines serving SFO to 

voluntarily adjust schedules to reduce delays. 
FACT3: Airport Capacity Needs in the National Airspace System

Page 4 January 2015 

• NextGen has benefits that may prove to be as important as outright capacity

enhancement. Significant improvements in the reliability and predictability of operations

across the NAS will help airlines better maintain and recover flight schedules during

inclement weather. However, these predictability and reliability benefits will not be

readily apparent in the high-level systemwide capacity benefits presented in the FACT3

report.

• Gates and taxiway infrastructure do not constrain capacity at most airports, now or in

the future. In general, the largest and busiest airports have been able to build gates

when they are needed—and many airports are making better and more efficient use of

their gates through more flexible leasing arrangements.

Recommendations 

• While NextGen capabilities will mitigate delays at the capacity-constrained airports,

congestion will continue to impede efficiency and growth. The remaining gap shows why

additional solutions such as new runways, regional emphasis, congestion management,

multimodal transportation, and further NextGen development are so important.

• Given the evolving trends and shifts in the aviation industry, along with a much higher

level of volatility, there is considerable uncertainty surrounding any projection that is

nearly two decades into the future (i.e., the 2030 scenarios). Sources of uncertainty

include traffic growth, how quickly the airlines add larger aircraft to their fleet to replace

smaller aircraft, demographic and socioeconomic shifts, and the realization of capacity

improvements from NAS modernization initiatives. However, with several consecutive

years of sustained operations growth at any of the Core airports, the long-term delay

concerns will become much more tangible. As a result, it remains crucial for these

airports to continue their efforts to devise long-term planning solutions to address

capacity constraints.

• The immediate focus should be on identifying solutions for airports identified as

capacity-constrained in any of the 2020 scenarios. These airports are likely to be

capacity-constrained under a variety of scenarios. Airports such as SFO and the NYC

area airports cannot easily be expanded to meet unconstrained demand. At the NYC

area airports, FAA limits on operations are currently in effect. If the schedule limits

continue due to future regulatory action, this will not diminish the need for capacity

enhancement at the NYC area airports. A focused effort will be needed to identify viable

solutions that can be implemented during this decade.
FACT3: Airport Capacity Needs in the National Airspace System

Page 5 January 2015 

METHODOLOGY AND INPUTS – WHAT HAS CHANGED SINCE 

FACT2? 

The FAA has undertaken this third FACT analysis in order to identify airports that are 

expected to have capacity needs in the future, given several possible scenarios for demand 

growth and capacity expansion. 

Much has changed since the publication of FACT2 in 2007. The aviation industry in the 

United States has continued to evolve. Due to the Great Recession and volatile (often 

higher) fuel costs, airlines have emphasized better ticket yields and fees, rather than 

improved market share, as a strategy for profitability. Airlines have consolidated through 

mergers and have increasingly focused their connecting operations at major hubs. While 

the use of 50-seat RJs has increased substantially during the last decade, these aircraft are 

now leaving the fleet due to their higher fuel costs and upcoming major maintenance cycles. 

Collectively, these factors have resulted in relatively flat operations and enplanement 

growth over the last few years. As a result, FAA forecast estimates 32 percent fewer 

operations in 2025 at the 30 Core airports than the forecast used in FACT2. 

FACT3 is scoped to incorporate many of these trends. In addition to updated forecasts, the 

FACT3 analysis includes current aircraft fleet mix projections, updated NextGen planning 

(which has matured substantially since 2007), and modeling of gate and surface constraints 

on airport capacity. FACT3 also contains refined modeling and selection criteria. 

This section identifies several changes made to the FACT process since the publication of the 

FACT2 report. Appendix B provides more detail on the methodology. Appendix C provides 

a summary of the FACT input changes through the various iterations of this report. 

Appendix D provides a sensitivity analysis of the FACT3 findings, given the changes in 

forecasted demand with the FAA’s annual forecast update.

Updated Forecast and Fleet Mix Data 

The FACT3 analysis uses the 2012 version of the FAA’s TAF, as published in January 2013.4 

At the 30 Core airports, the TAF forecasts 14.2 million total operations and 606.5 million 

enplanements in 2020. In 2030, 16.7 million total operations and 769.0 million 

enplanements are forecast. This reflects annualized operational growth of 1.1 percent 

through 2020 and then 1.6 percent through 2030. Enplanements are forecast to grow at a 

faster rate of 2.1 percent through 2020 and then 2.7 percent to 2030. The average seat 

per aircraft in the fleet is expected to increase over this period, as enplanements are 

forecast to grow faster than operations. 

The original FACT1 report was based on the TAF released in 2003, while the FACT2 report 

used the 2005 release of the TAF, as well as MITRE CAASD’s Future Air Traffic Estimator5

(FATE) forecast. The 2003 and 2005 TAFs were reflective of a period in which the aviation 

industry was recovering from the September 11, 2001, terrorist attacks and the economy 

4The FAA updates the TAF every year. 

5The FATE forecast methodology is being transferred into the FAA’s modernized TAF, known as TAF-M.
FACT3: Airport Capacity Needs in the National Airspace System

Page 6 January 2015 

was growing steadily. In contrast, the 2013 TAF used in the FACT3 report shows the effects 

of the economic contraction in 2008 and 2009 on the aviation industry and the stabilization 

of the industry through 2012. Figure 1 provides a comparison of the TAF operational levels 

at the 30 Core airports from FACT2 to FACT3. 

Figure 1. Actual and Forecasted Annual Operations at 30 Core Airports 

Because the TAF is a forecast of unconstrained demand, FACT3 seeks to evaluate long-term 

capacity needs of the airport system as needed to meet demand growth without constraints. 

However, at a few very congested airports, a trimming algorithm is used to smooth 

schedule peaks and limit operations in the FACT3 analysis.6 Even with trimming, these 

airports remain highly delayed. 

Fleet mix is a particularly important factor in assessing future airport congestion. For a 

given number of passengers who want to travel by air, a fleet with a smaller average seat 

count will result in more aircraft operations. This trend was evident in the last decade with 

the increasing use of 50-seat RJs. However, the current trend is towards somewhat larger 

aircraft, which are more fuel efficient as reflected in the current TAF. For the same amount 

of growth in passengers, this results in a lower rate of growth in aircraft operations. The 

amount of benefit with some NextGen improvements, such as Wake Recategorization, is 

also dependent on fleet mix. The NAS-wide simulation used in FACT3 includes a dynamic 

fleet mix that evolves over time using the FAA Fleet Forecast. FACT3 also uses an annual 

service volume (ASV) model with a static fleet mix based on the current fleet at an airport. 

The separate fleet mix assumptions provide useful variation in the estimates of future 

delays at an airport. 

6The trimming algorithm is meant to mimic historical airline and FAA actions at ORD, LGA, JFK, and EWR to reduce 

delays. However, the trimming algorithm does allow some growth in future years, including growth above the 

current FAA schedule limits at the NYC area airports. 

0

5

10

15

20

25

1980 1985 1990 1995 2000 2005 2010 2015 2020 2025 2030

Annual Aircraft Operations (Millions) at 

30 Core Airports

Year

TAF2005 (FACT2)

TAF2012 (FACT3)
FACT3: Airport Capacity Needs in the National Airspace System

Page 7 January 2015

Planned Improvements: Runways, NextGen, and NAS Modernization

The FACT3 analysis includes planned improvements affecting runway capacity for two future 

planning periods, 2020 and 2030. The FACT estimates of future capacity needs incorporate 

the best available information about planned improvements to the ATC system, as well as 

runway and airport infrastructure improvements. 

FACT3 is aligned with the FAA’s overall NextGen implementation strategy in order to 

incorporate relevant NextGen assumptions into the study. NextGen is a portfolio of 

capabilities that will improve the capacity, efficiency, safety, and environmental 

performance of the NAS. NextGen planning has matured greatly since the publication of 

FACT2 with the formation of the FAA’s NextGen office. The FAA published the NextGen 

Implementation Plan (NGIP), which provides an overview of NextGen capabilities and 

implementation timeframes. The NextGen assumptions used in FACT3 are derived from 

the Agency’s overall NextGen planning, including the NGIP as well as internal planning 

documents,

7 which describe NAS modernization efforts extending to the year 2020.

FACT3 assesses the capacity benefits of NextGen concepts at airports and estimates how 

they will help reduce growth in delays through enhanced ATC techniques, technologies, and 

procedures. While capacity is a NextGen benefit, it is important to note that many of the 

capabilities are more focused on efficiency, shared situational awareness, and flexibility.8 

These will improve the predictability and reliability of the NAS in ways that are perhaps 

more important than capacity, by allowing more nimble reroutes of air traffic around lines of 

thunderstorms; or allowing a faster recovery of normal operations when a weather event 

impacts a metropolitan area (such as a snowstorm in the Mid-Atlantic region). While these 

types of benefits are not assessed in the FACT3 models and metrics, the overall benefit to 

the NAS should not be underestimated. 

Two primary scenarios are used in FACT3 to assess airport capacity and congestion in 2020 

and 2030 as shown in Figure 2. The improvements included in each scenario are described 

on the following pages.

 

7

FAA NAS Segment Implementation Plan (NSIP), version 4. The FACT3 assumptions reflect elements of Segment 

A for near-term NextGen and the remainder of Segment A plus Segment B for midterm NextGen.

8When used in the context of NextGen benefits, efficiency is often used to describe fuel savings that result from 

optimized flight procedures. Efficiency in this context does not necessarily indicate delay savings related to 

capacity enhancement.
FACT3: Airport Capacity Needs in the National Airspace System

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Figure 2. FACT3 Scenarios in 2020 and 2030

Improvements

Reference 

Scenario:

No further 

improvements beyond 

near-term NextGen

Improvements 

Scenario: 

After planned 

improvements with 

mid-term NextGen 

and runways

Existing airport infrastructure as of 2011

New or extended runways at FLL, ORD, 

and PHL

Near-term NextGen

Mid-term NextGen

New or revised ATC flight procedures,

including airspace redesign

Existing noise abatement procedures

Gate development plans

The Reference Scenario, which encompasses no further improvements beyond near-term 

NextGen, includes existing airport infrastructure (as of 2011), as well as existing ATC 

procedures and airspace design. Also included are new or extended runways that have 

opened at ORD, Seattle-Tacoma International Airport (SEA), Washington Dulles 

International Airport (IAD), PHL, and Charlotte/Douglas International Airport (CLT), since 

FACT2 was published. This scenario includes mature NextGen capabilities that are expected 

to be widely deployed in the NAS within the next few years:

 Near-term NextGen: From an implementation perspective, NextGen is a long-term, 

incremental program. The initial building blocks establish the foundation for future 

segments of NextGen to be implemented. FACT3 evaluates two segments of NextGen 

and their effects on airport capacity. The first segment, known as near-term NextGen,

includes the capabilities in the NGIP that are mature, funded and are either being 

deployed today or will achieve initial deployment in the NAS by the end of 2015. ATC 

capacity improvements include the initial phase of Wake Recategorization, an increased 

use of Traffic Management Advisor and Converging Runway Display Aids, and a 

demonstration of Wake Turbulence Mitigation for Departures. Several improvements to 

dependent and independent closely spaced parallel operations are also included. The 

implementation, use, and benefit of these tools and procedures vary, given the unique 

configurations and operational needs of an airport. 

The Improvements Scenario includes the following additional planned improvements:

 New or Extended Runways. New runways are included in FACT3 at FLL, ORD, and 

PHL as planned improvements. At FLL, the extended and widened Runway 10R/28L
FACT3: Airport Capacity Needs in the National Airspace System

Page 9 January 2015

opened in September 2014. At ORD, the completion phase of the O’Hare Modernization 

Program is planned by 2020.9 Two runway extensions are planned at PHL by 2020 as 

part of its Capacity Enhancement Program (CEP). All of these runway projects are 

included in the 2020 Improvements Scenario.10 

The completion of the new parallel river runway at PHL, which is planned for early in the 

next decade, is incorporated into the 2030 scenario with planned improvements at PHL. 

Runway improvements are being considered at other airports as well, and several sitespecific studies are underway at Denver International Airport (DEN), George Bush 

Intercontinental/Houston Airport (IAH), CLT, and ATL. However, these projects have not 

reached sufficient maturity to be included in FACT3.

 Midterm NextGen. The second segment of NextGen capacity improvements builds on 

the capabilities achieved in the near-term segment. ATC capacity improvements include

use of Wake Turbulence Mitigation for Departures at additional airports; enhanced 

closely spaced parallel runway operations, including Wake Turbulence Mitigation for 

Arrivals; and improved metering of traffic within congested terminal airspace. Improved 

departure fanning enabled by RNAV routes is also expected at several airports. The 

integration of NextGen communications, navigation, and surveillance capabilities is also 

estimated to improve the precision and reduce the separation buffer of arrivals coming 

into congested airspace and airports. Overall, the midterm segment includes capabilities 

that are expected to be achieved in the NAS by 2020. 

 New or Revised ATC Procedures. If a new or revised ATC procedure is planned at an 

airport by FAA, with either NextGen or a complementary NAS modernization initiative, it 

was modeled as an improvement in this report. Examples include increased use of 

simultaneous offset approaches at SFO and improved departure throughput with RNAVbased departures at ATL.

 Airspace Redesign. Improvements derived from the redesign of the airspace 

surrounding an airport were reflected in the 2020 scenarios based on the best 

information available. This includes longer-term airspace projects such as the Las Vegas

and New York/New Jersey/Philadelphia airspace redesigns, as well as completion of the 

first phase of the FAA’s Metroplex11 initiative to streamline Performance Based 

Navigation (PBN) routes and procedures. Airspace redesign efforts are primarily focused 

on efficiency (including fuel burn and route mileage reductions) and flexibility 

improvements, rather than capacity. Detailed airspace redesign itself was not 

performed as part of this analysis.

 

9Completion of the O’Hare Modernization Program includes Runways 10C/28C in 2013 and 10R/28L in 2015. The 

Runway 9C/27C and 9R/27L extensions are assumed to be completed by 2020.

10PHL CEP includes extension of Runways 8/26 and 9R/27L by 2020 and then construction of a new south parallel 

runway along the Delaware River a few years later. As such, this runway is included in the 2030 improvement 

scenarios. 

11Also known as Optimization of Airspace and Procedures in the Metroplex (OAPM).
FACT3: Airport Capacity Needs in the National Airspace System

Page 10 January 2015

 Other Assumptions. The FACT3 analysis assumed that existing noise abatement 

procedures, which can affect runway capacity, would continue as is into the future 

planning periods. Terminal gate development plans were also included. Detailed 

taxiway or ground access improvements were not included in this analysis because they 

were outside the scope of the models used.

Airport Selection

The goal of FACT is to identify those airports that are expected to be capacity-constrained in 

the future; however, it is impractical to analyze all of the existing 3,330 airports in the 

FAA’s National Plan of Integrated Airport Systems (NPIAS) to the required level of detail. 

Therefore, a screening method was used to select candidate airports where excessive delays 

could potentially have a significant impact on the efficiency of the NAS, including:

• Core airports: 30 commercial service airports that have been identified by FAA as 

having a significant role in the NAS due to their level of operations or passengers;

• Potentially constrained commercial airports: commercial service airports with projected 

traffic growth that may stress their current capacity; and

• General aviation airports: other airports with a substantial level of traffic, even if 

primarily general aviation, which can affect airspace and air traffic in multi airport areas 

like New York and Southern California.

In all, 48 airports were included in the FACT3 analysis as shown in Appendix A.

Models and Identification Criteria

As in FACT2, the FACT3 analysis was based on both ASV and NAS-wide modeling tools. The 

use of two modeling techniques is a strength of the FACT approach as the synthesized 

results can incorporate a comprehensive set of operational parameters.

ASV calculates the yearly demand that results in a given level of average delay in simulated 

operations. ASV studies are conducted by the Capacity Analysis Group (AJR-G5) at the 

FAA’s William J. Hughes Technical Center. ASV analysis considers multiple runway 

configurations, weighted by the annual frequency of occurrence, and utilizes an annual 

estimation of weather conditions for each configuration in its calculation. The resulting 

demand-delay curve can be used to estimate the average annual delay that results at a 

given level of annual demand. 

As the name implies, NAS-wide simulations allow for the assessment of aircraft operations 

across the entire system. MITRE CAASD conducts NAS-wide studies for the FACT reports. 

Calculated capacity curves are used for each airport with adjustments over time for future 

fleet mixes. With faster processing capability, 16 demand days, with a mix of weather 

conditions, are simulated for each scenario (versus only two traffic scenarios, “good 

weather” and “bad weather” for FACT2). NAS-wide modeling was expanded from runways 

and airspace to include taxiway and gate constraints. 
FACT3: Airport Capacity Needs in the National Airspace System

Page 11 January 2015

Both the ASV and the NAS-wide models were used to define whether an airport would be 

considered “congested” or “capacity-constrained” in a scenario.12 13

• Caution: this status identifies airports that are not capacity constrained but have 

delays approaching the capacity-constrained criteria. An airport falls into this caution 

designation if the ASV delay was 5 minutes or greater or the percentage of congested 

hours14 was 20 percent or greater for either arrivals or departures.

• Congested: to be designated as capacity constrained or congested, an ASV delay of 

7 minutes per flight or greater was needed, as well as an NAS-wide estimate of 

30 percent or more of the arrival or departure hours at the airport being congested.

• Severe: as a subset of the capacity-constrained airports, some airports have estimated

delay and congestion that are an order of magnitude higher than the initial criteria for 

identification. An ASV delay of 15 minutes or greater and a percentage of congested 

hours at or above 50 percent is considered to be severely capacity constrained.

Given the consolidation of airline operations at fewer airports and the general challenges of 

applying a macro-level approach to regional system planning, the identification of congested 

metropolitan areas is less significant today than when done in the FACT2 report. 

Accordingly, the designation of metro areas as congested is not included in the FACT3

report. Nonetheless, this report recognizes that certain key metro areas with multiple 

airports, such as the NYC area, are effectively congested under almost any measure due to 

airport delays and airspace complexity. Where possible, encouraging traffic growth to 

unconstrained airports in a metro area is worthwhile but often has practical constraints. 

Effectively, the analysis of metro area airport systems is better conducted with a more 

regionally focused methodology than is possible with FACT.

Airport Capacity Profiles and ASV Studies

As a companion publication to the FACT3 report, capacity curves similar to those used in the 

NAS-wide modeling are available for selected airports on the FAA Web site. The airport 

capacity profiles provide a range of model-estimated and facility called rates for both 

existing and future conditions. The profiles replace the benchmarks that were last published 

in 2004. In addition, the ASV studies are available to airport sponsors upon request.

 

12FACT3 criteria must not be considered as an FAA definition of acceptable delay for the purpose of justifying 

proposed airport development without prior consultation with the FAA’s Office of Airport Planning and 

Programming, Airport Planning and Environmental Division (APP-400).

13Due to the complexity of operations at LGA, only the NAS-wide model was used to assess future congestion at the 

airport.

14A congested hour is defined by having a high level of delay for either arrivals or departures. A congested delay 

level is defined as the 90th percentile value seen at the 30 Core airports in the 2011 NAS-wide baseline 

simulation. The hours between 0700 and 2259 local time on the 16 representative days were considered in the 

determination and application of this metric. See Appendix B for additional information.
FACT3: Airport Capacity Needs in the National Airspace System

Page 12 January 2015 

COORDINATION WITH AFFECTED AIRPORTS 

During May, June, and July 2014, the FACT3 analysis was briefed to each of the airports 

identified as being capacity constrained in future years. Each airport operator was briefed 

on the assumptions used in the analysis, as well as the draft results. Often, the airport 

operator agreed with the FACT3 analysis. Others thought the analysis may have over- or 

under-estimated airport capacity. Several airports noted changes in gate assignments or 

terminal development plans, as well as the ongoing effects of airline mergers. 

Ongoing changes at airports are expected of course. Given the medium-level fidelity of the 

models used in this report, the primary value of the simulation modeling is for trend 

analysis. New gate assignments and similar smaller-scale changes do not substantively 

affect the long-term trends projected by FACT3. This is because the trend projections for 

future delays are more relevant and telling than a single-point, deterministic value that can 

vary with small changes. 

FINDINGS OF THE FACT3 REPORT 

Consistent with FACT2, this report also finds that several of the Nation’s busiest hub airports 

are and will be capacity constrained in future years. 

As would be expected, the findings from the various iterations of FACT have evolved over 

time. Effectively, while aggregate future demand is lower than in previous FACT reports, 

the ability of the NAS to handle demand is also greater. Ten of the 30 Core airports have 

been successful in adding new runway capacity with either new runways or extensions, 

since the first FACT report was published in 2004. The ATC has also enhanced efficiency 

with airspace redesigns, including improved flight routes and procedures. Many large hub 

airports have seen steady traffic growth as airlines have sought to increasingly focus 

connecting traffic at their established hubs. Other airports have seen significant and 

sustained reductions in operations. As a result, some airports are no longer designated as 

congested by FACT. A full comparison of the FACT findings by airport is provided following 

the Administrator’s introductory letter.

As a macro-level assessment of the airport system, FACT3 is not intended to evaluate all 

aspects of an operation at each individual airport. For example, some airports may have 

taxiway limitations that cause significant operational delays on the surface. While FACT3 

does reflect consideration of general surface and gate constraints, it does not use a detailed 

taxiway layout. Airports have many different runway configurations used throughout the 

year. Most airport configurations are captured in the ASV model; however, the NAS-wide 

modeling is limited to the three most common runway configurations during visual, 

marginal, and instrument conditions. As such, the performance of an individual airport may 

not be fully represented, and some future problems may not be captured or identified. While 

FAA considers the FACT3 findings to be representative of the future performance of the 

airport system, the limitations discussed above do influence the overall results. 

The FACT3 analysis should be considered in combination with studies being prepared for 

specific airports. These studies are focused specifically at the airports of interest and may 

be more detailed and take into consideration additional constraints not accounted for in the 

FACT3 methodologies. Furthermore, inclusion of capacity enhancement for which there is an 

ongoing National Environmental Policy Act evaluation should not be construed as 

predetermination of approval by FAA, but rather as a “what-if” assessment of potential 

benefit. Similarly, inclusion of an NAS modernization initiative that has not yet been 
FACT3: Airport Capacity Needs in the National Airspace System

Page 13 January 2015

approved through the FAA’s acquisition and safety processes should not be construed as an 

FAA commitment to implement a given ATC improvement at a specific airport. Noise 

abatement restrictions, where they presently exist, were assumed to continue unchanged.

When interpreting the results of FACT3 as compared to site-specific studies, it is important 

to keep in context the purpose of the FACT process and the changes made since FACT1 and 

FACT2. As a systemwide analysis, FACT is intended to provide FAA with macro-level 

insights about the timing, need, and magnitude for both infrastructure and NAS 

modernization improvements. This is meant to inform the FAA’s strategic planning. While 

the FACT analysis is also meant to provide airport sponsors with insights about NAS 

modernization plans, it cannot replace site-specific studies that examine capacity issues in 

detail and are thus more accurate reflections of the situation at a particular airport.

The following sections identify airports that FACT considers to be capacity constrained or 

congested in the applicable scenario and timeframe. This designation is based on the 

airport meeting both the FACT3 delay and congestion criteria. Some airports are designated 

as having a caution status, which means they experience some level of delay but do not yet 

meet the FACT3 criteria to be considered congested. A few airports are considered to have 

severe congestion as they exceed the FACT3 criteria by a significant margin.

Congested Airports in 2011

The FACT3 analysis identified five airports that are currently congested and would benefit 

from additional capacity as shown in Figure 3.

Not surprisingly, the three major NYC area airports, EWR, JFK, and LGA, are congested. All 

three airports regularly experience delays. As a result, all three airports are currently 

subject to FAA limits on operations. While the ongoing airspace redesign effort and 

NextGen enhancements will help to improve efficiency and flexibility, FAA sees strong 

evidence that additional runways may be the best long-term solution to meet future 

demand for intercity travel to and from the NYC area.

PHL continues to regularly experience significant delays. As a result, the airport is pursuing 

its CEP to mitigate delays and meet future growth. The CEP includes two runway extensions 

and a new parallel runway, as well as terminal area and other airport improvements.

ATL also meets the FACT3 criteria to be considered congested, although the airport has seen 

significant delay reduction with the opening of its fifth parallel runway in 2006. ATL can be 

congested during certain periods of the day because of the extensive connecting hub 

activity at the airport.
FACT3: Airport Capacity Needs in the National Airspace System

Page 14 January 2015 

Figure 3.

Airports Needing 

Capacity Today 

(2011)

Five airports today are considered congested by the FACT3 criteria

(as shown in red), with four others having caution status (as shown 

in yellow). The airports shown in green were evaluated in FACT3 

but generally are not congested.

Interim Capacity Needs in 2020

The capacity needs in the 2020 midterm planning period were evaluated with two scenarios: 

1. Reference Scenario: this scenario includes the 2011 baseline conditions (runways and 

airspace), with the implementation of mature, high-confidence, near-term NextGen 

improvements. 

2. Improvements Scenario: this scenario assumes completion by 2020 of all planned 

runway development projects at ORD and FLL; two runway extensions at PHL; enhanced 

ATC procedures and airspace redesign; and NAS modernization initiatives included in 

midterm NextGen. Both scenarios assume forecasted demand growth through 2020 at a 

rate of about 1.1 percent annually for Core airports consistent with the 2012 TAF. 

Figure 4 shows both scenarios; results are also shown in Table 1. Comparison of the 

scenarios reveal where additional capacity will be needed in the future; what effect the 

improvements that are currently underway or in the planning process will have on future 

capacity needs; and where new initiatives will be needed to provide even greater capacity 

beyond what is currently in the construction or planning process. 
FACT3: Airport Capacity Needs in the National Airspace System

Page 15 January 2015

Table 1.

Airports Needing 

Additional 

Capacity in 2020 

Airports Needing Additional Capacity

Reference:

No further 

improvements 

beyond nearterm NextGen

Improvements:

After planned 

improvements 

with midterm 

NextGen and 

runways

ATL Hartsfield-Jackson Atlanta Int’l  

EWR Newark Liberty Int’l  

JFK John F. Kennedy Int’l  

LGA New York LaGuardia  

PHL Philadelphia Int’l  

SFO San Francisco Int’l 

Total 6 5

A comparison of the two scenarios allows for consideration of several possible outcomes 

affecting airport system performance. In both scenarios, ATL, EWR, JFK, LGA, and PHL will 

be capacity constrained. Delays at LGA and JFK are expected to increase to severe levels, 

exceeding the FACT3 criteria significantly.15 While midterm NextGen improvements are not 

sufficient to bring these airports below FACT3 criteria, the airports will nonetheless 

experience significant reductions in delay and congested hours with NextGen. SFO will 

become capacity constrained if expected midterm NextGen improvements are not achieved.

If NextGen implementation is delayed due to budgetary constraints or technical readiness, 

then the reference scenario provides a conservative estimate of airport capacity and delay.

 

15The baseline modeling is representative of operational conditions as they occurred in 2011, which includes the 

existing schedule limits for the NYC area airports. For 2020 and 2030, the trimming algorithm is used by the 

NAS-wide model to constrain future demand at these airports. However, the trimming algorithm does allow 

moderate operations growth beyond the current schedule limits. As a result, the future congestion status of the 

NYC area airports is indicative of higher traffic levels than currently allowed by the FAA schedule limits.
FACT3: Airport Capacity Needs in the National Airspace System

Page 16 January 2015 

Figure 4.

Airports Needing Additional 

Capacity in 2020

Midterm NextGen improvements reduce the percentage 

of congested hours at airports, as shown in the lower 

map. However, even with additional capacity gained 

from the planned improvements expected by 2020, the 

FACT3 analysis identifies five airports that will still need 

additional capacity.

2020 Reference Scenario 

No further improvements beyond near-term NextGen

2020 Improvements Scenario 

After planned improvements with midterm NextGen 

and runways
FACT3: Airport Capacity Needs in the National Airspace System

Page 17 January 2015 

Needed Capacity Beyond What is Currently Planned for 2020

By incorporating the additional capacity gained from the planned improvements expected by 

2020 to the 2011 baseline capacities, and measuring this against the forecasted demand for 

2020, the FACT3 analysis identified five airports that will need additional capacity beyond 

what is already planned (see Figure 4 and Table 1).16

 EWR, LGA, and JFK: The Port Authority of New York and New Jersey has embarked on a 

long-term planning study to assess the feasibility of adding new runways to these 

congested hub airports. While it is too early to determine the outcome of this initiative, 

the FACT3 findings make clear the need for additional capacity enhancements within the 

NYC area. 

 ATL: The city of Atlanta is developing an update to its master plan to assess future 

facility requirements, including assessment of the need for further runway development. 

ATL’s fifth runway opened in 2006 providing significant capacity benefit. If demand 

grows as expected, delays will also increase. With its master plan, ATL is expected to 

identify needed further capacity improvements and their timeframe for implementation. 

 PHL: The Environmental Impact Statement (EIS) for the complete reconfiguration of its 

airfield was completed in 2010. In 2020, FACT3 included two runway extensions that 

are part of the CEP in the planned improvements scenario. While these extensions 

provide delay benefits, the long-term analysis also shows that the planned parallel river 

runway is needed to further enhance capacity. 

Airport Capacity Improvements by 2020

A comparison of the airports needing additional capacity with and without planned 

improvements in 2020 reveals that a single airport, SFO, will come off the list of capacity 

constrained airports if the planned improvements are completed. This is due to improved 

metering of arrivals to the runways with midterm NextGen capabilities. These 

improvements will also benefit other airports. Table 2 shows the model-estimated hourly 

capacity improvement by airport. Of course, airfield capacity at ORD, PHL, and FLL also 

improves with new or extended runways. 

 

16Capacity and delay estimates are specific to the planning years identified (i.e., 2011, 2020, and 2030). 

Intermediate years were not analyzed. 
FACT3: Airport Capacity Needs in the National Airspace System

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Table 2. Capacity Enhancement and Congestion Reduction in 2020

Airport

Reference Scenario

No further improvements beyond 

near-term NextGen

Change with Improvements Scenario

After planned improvements 

with midterm NextGen and runways**

Weighted, 

Balanced 

Hourly 

Capacity

Arrival 

Congestion (% 

hours)

Departure 

Congestion 

(% hours)

Weighted, 

Balanced 

Hourly 

Capacity

Arrival 

Congestion (% 

hours)

Departure 

Congestion (% 

hours)

ATL 212 73% 48% +6 -14% -2%

CLT 166 65% 68% +16 -25% -3%

EWR 82 55% 60% +3 -19% -10%

FLL 79 20% 26% +41 -18% -2%

IAH 171 9% 5% +16 -5% 0%

JFK 85 52% 63% +5 -12% -8%

LAS 106 9% 27% +1 -5% 0%

LGA 81 67% 62% +3 -13% 0%

ORD 231 28% 8% +41 -18% -7%

PHL 115 72% 47% +13 -38% +1%

PHX 142 10% 18% +1 -3% +4%

SFO 91 21% 30% +2 -3% -2%

**Change is arithmetic difference between two percentages, not the percent difference.

Long-Term Capacity Needs in 2030

The capacity needs in the 2030 long-term planning period were evaluated with the same 

two scenarios as evaluated in 2020, but with completion of the PHL CEP, including a new 

parallel runway in the improvements scenario. Both scenarios assume forecasted demand 

growth from 2020 to 2030 at a rate of about 1.6 percent annually for Core airports as 

projected in the 2012 TAF.

While there are additional NextGen capacity improvements in the FAA’s Mid-Term Concept 

of Operations, these concepts are not yet sufficiently mature to include in the FACT3 

modeling. This includes paired approaches to closely-spaced parallel runways in instrument 

meteorological conditions (IMC), and interval management with Automatic Dependent 

Surveillance-Broadcast (ADS-B) In for precise metering and spacing. Nonetheless, the 

capacity benefits of the ultimate NextGen capabilities are considered to be significant.

Figure 5 shows both long-term scenarios; results are also shown in Table 3. Comparison of 

the scenarios reveal where additional capacity will be needed in the future; the effect of 

improvements that are currently underway or in the planning process on future capacity 

needs; and where new planning efforts will be needed to provide even greater capacity 

beyond what is currently in the construction or planning process. 
FACT3: Airport Capacity Needs in the National Airspace System

Page 19 January 2015 

Table 3.

Airports Needing 

Additional Capacity 

in 2030

Airports Needing

Additional Capacity

Reference:

No further 

improvements 

beyond near-term 

NextGen

Improvements:

After planned 

improvements with 

midterm NextGen 

and runways

ATL Hartsfield-Jackson Atlanta Int’l  

CLT Charlotte Douglas Int’l  

EWR Newark Liberty Int’l  

FLL Fort Lauderdale/Hollywood Int’l 

IAH George Bush Intercontinental/Houston  

JFK John F. Kennedy Int’l  

LAS McCarran Int’l  

LGA LaGuardia  

ORD O’Hare Int’l 

PHL Philadelphia Int’l 

PHX Phoenix Sky Harbor Int’l  

SFO San Francisco Int’l  

Total 12 9

Needed Capacity Beyond What is Currently Planned for 2030 

The FACT3 analysis identified nine airports that will need additional capacity beyond what is 

already planned (see Figure 6 and Table 4).17 Four of these airports are a continuation of 

the additional capacity needs identified in the 2020 scenarios. The remaining five airports 

that will need additional capacity beyond what is currently planned for 2030 include: 

 CLT: Planning is underway to evaluate the capacity benefits for a fourth parallel runway. 

 IAH: The Houston Airport System had begun an EIS for two additional runways; 

however, this initiative was stopped due to reductions in traffic. With resumptions in 

traffic growth, IAH has options to develop additional runways. 

 LAS: LAS has suspended the immediate efforts for a new secondary commercial airport 

for the Las Vegas region to supplement LAS. However, the option for a supplemental 

airport remains a future possibility if needed to meet long-term traffic growth. 

 PHX: Additional runway capacity will be needed if demand continues to grow as 

forecasted. The city of Phoenix Aviation Department is working with Phoenix-Mesa 

Gateway Airport (IWA), in nearby Mesa to increase the use of this airport for scheduled 

commercial service. 

 SFO: Given its physical constraints, SFO has been participating in a regional planning 

effort to address capacity needs within the San Francisco Bay area. 

 

17Capacity and delay estimates are specific to the planning years identified (i.e., 2011, 2020, and 2030). 

Intermediate years were not analyzed. 
FACT3: Airport Capacity Needs in the National Airspace System

Page 20 January 2015 

2030 Reference Scenario 

No further improvements beyond near-term NextGen

Figure 5.

Airports Needing 

Additional 

Capacity in 2030

With forecasted growth in demand, the FACT3 analysis identifies 

nine airports that will need additional capacity beyond what is 

currently planned in 2030 as shown on the lower map. This analysis 

shows why additional solutions such as new runways, regional 

emphasis, congestion management, multimodal transportation, and 

NextGen are so important.

2030 Improvements Scenario 

After planned improvements with midterm NextGen 

and runways
FACT3: Airport Capacity Needs in the National Airspace System

Page 21 January 2015

Airports Capacity Improvements by 2030

A key finding of FACT3 is that runway development continues to be critical to meet future 

growth in demand. Three airports, ORD, FLL, and PHL, come off the list of capacityconstrained airports due to planned runway development. This demonstrates the 

effectiveness of adding new runway capacity, where needed, to meet long-term aviation

growth. Table 4 shows the capacity and congestion reduction benefits of these runway 

development projects.

Table 4. Capacity Enhancement and Congestion Reduction in 2030

Airport

Reference

No further improvements beyond near-term NextGen

Improvements

Change after planned improvements with 

midterm NextGen and runways

Weighted,

Balanced 

Hourly 

Capacity

Arrival 

Congestion 

(% hours)

Departure 

Congestion

(% hours)

Weighted,

Balanced 

Hourly 

Capacity

Arrival 

Congestion (% 

hours)

Departure 

Congestion (% 

hours)

ATL 212 89% 70% +5 -7% +2%

CLT 164

88% 86% +16 -6% -2%

EWR 82 76% 84% +8 -13% -3%

FLL 79 62% 62% +42

-30% -3%

IAH 169 65% 58% +16 -20% +1%

JFK 84 80% 92% +5

-11% -2%

LAS 107 70% 79% +1

-6% -3%

LGA 81 71% 70% +3

-10% +3%

ORD 235 73% 39% +41 -29% -18%

PHL 113 92% 80% +50 -32% -8%

PHX 148

66% 63% +7 -13% +2%

SFO 91 72% 62% +3 -12% -6%

**Change is arithmetic difference between two percentages, not the percent difference.

Airports With Some Congestion to be Monitored

The FAA believes the criteria used in this report have appropriately identified locations 

where additional capacity enhancements will be required. However, any report that 

attempts to identify future capacity constraints may not capture all the dynamics associated 

with the aviation industry and growth in demand. While the criteria provide a useful filter 

for determining the most significant capacity needs, the FACT methodology is not intended 

to identify and assess all airport capacity needs. 

Therefore, the findings in this report should not be considered a substitute for more detailed 

regional and airport-specific capacity studies. The FAA strongly encourages individual 

airport sponsors and regional planning organizations to undertake detailed studies to refine 

and build on the FACT3 findings and to provide a more thorough understanding of issues 

existing at particular airports. The FAA acknowledges that airports not identified in this 

report may still face capacity or other operational issues that will require future airport 

enhancements or that listed airports may become capacity constrained earlier or later than 

this analysis indicates. 
FACT3: Airport Capacity Needs in the National Airspace System

Page 22 January 2015

Because the aviation industry is constantly changing and some changes can be significant 

and swift, those airports that met the caution criteria used in this analysis (but not both 

criteria needed to be identified as capacity constrained) should be monitored to gauge the 

effects of potential changes on future delay. Considering the long lead time required for

implementing capacity enhancements, it is important to monitor delays at airports within 

the interim period (through 2020) as changes could expedite the need for additional 

capacity. Table 5 shows airports that meet the FACT3 criteria for caution status (i.e., ASV 

delay was 5 minutes or greater or the percentage of congested hours was 20 percent or 

greater for either arrivals or departures) in either 2020 or 2030 and thus should be 

monitored for increasing congestion.

Table 5.

Airports With 

Some Congestion 

to be Monitored

Airports Meeting Caution Criteria 2020 2030

BOS Boston Logan Int’l 

BWI Baltimore/Washington Thurgood 

Marshall International

 

DCA Washington Reagan National  

DEN Denver Int’l 

DFW Dallas Fort Worth Int’l 

DTW Detroit Int’l 

IAD Washington Dulles Int’l 

LAX Los Angeles Int’l  

MCO Orlando Int’l 

MDW Chicago Midway International 

MIA Miami Int’l  

MSP Minneapolis-St. Paul Int’l 

SAN San Diego Int’l 

SEA Seattle-Tacoma Int’l 

SNA John Wayne Orange County 

TEB Teterboro  

TPA Tampa Int’l 

Total 6 17

*This table does not include airports identified as capacity-constrained in Tables 1 and 3.

 

As part of its responsibilities to maintain the safety and efficiency of the NAS, FAA 

continuously tracks the performance of the NAS. The FAA monitors planned airline 

schedules in consideration of airport capacity and delay. The FAA analyzes current trends 

and their potential effects on future performance. If demand or delays grow more quickly 

than anticipated at an airport, FAA can then work with airport operators, their users and 

airlines, and their local communities to address their capacity enhancement needs.

CONCLUSIONS AND RECOMMENDATIONS

The FACT3 analysis identified airports that are expected to need additional capacity in two 

future time periods, 2020 and 2030. This assessment is based on current demand 

forecasts, plans for new or extended runways, and plans for ATC system improvements,

including NextGen.

Based on these assumptions, five airports will be significantly capacity constrained by 2020 

and nine by 2030, even after all currently planned improvements are implemented. The 

improvements that are already planned or underway are crucial to complete, but even so 

they will not be sufficient to address all of the shortfalls by 2020, let alone 2030. If 
FACT3: Airport Capacity Needs in the National Airspace System

Page 23 January 2015

planned improvements are not implemented as scheduled, one additional airport in 2020 

and three additional airports in 2030 are expected to be capacity constrained. This analysis 

shows why continued efforts to identify solutions, such as new runways, regional emphasis, 

congestion management, multimodal transportation, and NextGen are essential.

Notably, all of the airports identified in FACT3 as capacity constrained are large hub, Core 

airports. No smaller commercial service or general aviation airports that were evaluated in 

the report were identified as capacity constrained, although a few are in the caution 

category. This reflects the continued concentration of air traffic growth at major hubs. 

While NextGen will reduce growth in average delays by about 26 percent,

18 steady traffic 

growth as forecasted will nonetheless result in eight of the nine capacity-constrained 

airports in 2030 having severe congestion levels, affecting air travel nationwide.

Recognizing the evolving trends and shifts in the aviation industry, there is considerable 

uncertainty about any projection that is nearly two decades into the future (i.e., the longterm forecasts used in the 2030 scenarios from a 2011 projection). Sources of uncertainty 

include:

 traffic growth;

 how quickly the airlines add larger aircraft to their fleet to replace smaller aircraft;

 demographic and socioeconomic shifts; and

 the realization of capacity improvements from NAS modernization initiatives. 

However, with several consecutive years of sustained traffic growth at any of the Core 

airports, the long-term delay concerns will become much more tangible. As a result, it 

remains crucial for these airports to continue their efforts to devise long-term planning 

solutions to address capacity constraints.

Given future uncertainties, the focus for the remainder of this decade should be on 

identifying solutions for airports identified as capacity constrained in the 2020 scenarios. 

These airports are likely to be capacity constrained under a variety of scenarios.19 Airports 

such as SFO and the NYC area airports cannot be easily expanded to meet unconstrained 

demand. At the NYC area airports, the FAA limits on operations are expected to continue. 

A focused effort will be needed to identify viable solutions that can begin implementation.

Meeting the future capacity needs of the Nation’s airports will require innovative 

approaches, as well as continued emphasis on airport expansion and technological 

improvements. The following are some of the approaches that warrant further 

investigation:

 New Runways and New Airports. The most direct response to an expected capacity 

limitation is the expansion of existing airports to meet forecasted demand. New 

 

18 Reduced growth in delay is by comparison to the 2030 Reference Scenario.

19 Appendix D provides a sensitivity analysis of the FACT3 findings, given the changes in forecasted demand with 

the FAA’s annual forecast update. Even with changes in demand in the 2013 TAF, as compared to the 2012 TAF 

used in FACT3, the identification of constrained airports in 2020 remains substantively unchanged.
FACT3: Airport Capacity Needs in the National Airspace System

Page 24 January 2015 

runways almost always provide the most significant capacity improvements. New 

runways can also be part of a new airport, as has been considered in Las Vegas. Largescale airport development is rarely a straightforward process, especially near major 

population centers. Considerable lead time is necessary to implement planned airport 

capacity improvements. Master planning, site selection, financial planning, airspace, 

environmental studies, and land acquisition need to be conducted in a steadfast, 

collaborative manner to move a project through the development process. 

 Gates and Taxiways. Gate and taxiway infrastructure are not the primary constraints

to capacity at most airports, now or in the future. Gates and taxiways can usually be

built where and when needed.

 Regional Solutions. Studies of regional traffic and development alternatives have

been used to analyze specific air travel behavior within defined regions that

experience significant congestion, such as the San Francisco Bay area, NYC, and the

Boston/New England region. Several of these regions have ongoing study efforts and

intergovernmental collaboration in place. These initiatives should continue.

 Congestion Management. Fortunately, we can add capacity to solve most of our

problems. However, in some cases runway construction may not be a viable alternative.

Today, LGA is a good example. In the next 10 years, the San Francisco Bay area may

serve as an additional example of a capacity-constrained airport where runway

construction may not be a feasible option. In these cases, demand management,

regulatory or economic solutions, and other market mechanisms may need to be

investigated.

 High-Density Multimodal Transportation Modes. The majority of the U.S.

population is located along the coastlines in densely populated mega regions. Not

surprisingly, the FACT3 analysis has identified significant and consistent capacity 

problems at airports in some of these areas. The demand for travel in these highdensity intercity corridors requires the continued development of high-speed rail and bus 

modes to provide additional options along with short-haul air travel. In these dense 

mega regions, an “all of the above” approach is needed to advance the development of

multiple transportation options. Often, the high-speed surface modes will complement

air service and, where appropriate, can provide convenient and reliable access to

airports for connections to long-haul markets.

 NextGen. These findings indicate that FAA and its industry partners, including airports,

should continue to advance the development and deployment of NextGen. NextGen

concepts produced quantifiable delay reductions at nearly all airports included in this

report, either directly or by reducing delays at the airport that flights are going to or

coming from. The improvements may often be incremental, such as a moderate

throughput increase that may be the best option at airports that cannot easily add new

runways. Overall, NextGen capabilities are relevant to airports with planned runway

improvements, as well as for airports where geographic and other constraints prevent

easy physical expansion of the airfield.

NextGen has benefits that may prove to be more important than outright capacity 

growth. Significant improvements in the reliability and predictability of operations 

across the NAS will help airlines better maintain and recover flight schedules during 

inclement weather. These predictability and reliability benefits are not captured in the 
FACT3: Airport Capacity Needs in the National Airspace System

Page 25 January 2015

high-level systemwide capacity benefits estimated with FACT3, but they are nonetheless 

vital to NAS modernization.

 Runways and NextGen are Complementary. Capacity improvements from NextGen 

are not as significant as those from new runways, but are applicable to many airports

across the NAS. Still, if an airport is facing a substantial shortfall in capacity, the best 

answer is often new pavement. The optimal combination of solutions in each particular 

location depends on the scale of the capacity/demand imbalance and the specific 

operational issues that need to be addressed. Often, at congested airports, both are 

necessary to foster improved airport performance; e.g., NextGen improvements such as 

PBN may be needed to maximize the capacity benefits of a new runway.

This report has identified a number of airports where additional capacity is expected to be 

needed to handle expected future demand. By updating the FACT analysis, FAA has a 

strategic understanding of future airport capacity needs in the coming years. We can then 

work with airports, their users, and their local communities to address capacity enhancement needs. The solution at each airport will be different and can only be identified through 

consideration of local factors and concerns. The FAA is prepared to work with airports to 

address their capacity and demand challenges and to seek innovative approaches to their 

needs.
FACT3: Airport Capacity Needs in the National Airspace System

A-1 January 2015

APPENDIX A: STUDY AIRPORTS

The following 48 airports are included in this FACT3 analysis:

ID Airport Name Core

ATL Hartsfield-Jackson Atlanta International

BFI Boeing Field/King County International

BOS General Edward Lawrence Logan International

BWI Baltimore/Washington International Thurgood Marshall

CLT Charlotte/Douglas International

DCA Ronald Reagan Washington National

DEN Denver International

DFW Dallas/Fort Worth International

DTW Detroit Metropolitan Wayne County 

DVT Phoenix Deer Valley

EWR Newark Liberty International

FLL Fort Lauderdale/Hollywood International

FRG Republic 

FXE Fort Lauderdale Executive

GFK Grand Forks International

HND Henderson Executive

HNL Honolulu International

HPN Westchester County

IAD Washington Dulles International

IAH George Bush Intercontinental/Houston

ISP Long Island MacArthur 

IWA Phoenix-Mesa Gateway

JFK John F. Kennedy International 

LAS McCarran International 

LAX Los Angeles International

LGA LaGuardia 

LGB Long Beach/Daugherty Field

MCO Orlando International

MDW Chicago Midway International 

MEM Memphis International

MIA Miami International

MKE General Mitchell International 

MSP Minneapolis-St. Paul International/Wold-Chamberlain

OAK Metropolitan Oakland International

ORD Chicago O’Hare International 

PAE Shonomish County (Paine Field)

PHL Philadelphia International

PHX Phoenix Sky Harbor International

SAN San Diego International

SEA Seattle-Tacoma International

SFO San Francisco International

SJC Norman Y. Mineta San José International

SLC Salt Lake City International

SNA John Wayne Airport-Orange County

TEB Teterboro

TMB Kendall-Tamiami Executive

TPA Tampa International

VNY Van Nuys
FACT3: Airport Capacity Needs in the National Airspace System

B-1 January 2015

APPENDIX B: METHODOLOGY

Introduction

The objective of the FACT analyses is not to predict future ATC scenarios, nor to perform a 

benefits analysis of any improvements to the ATC system or to airports. Instead, FACT is 

intended to provide information about which airports are expected to be capacity

constrained in the future even with reasonably optimistic assumptions about future system 

performance. This information can then be used to scope additional efforts for systemwide 

analysis or airport-specific improvements.

Study Scope and Scenarios

The baseline for the FACT3 analysis is the year 2011. Two future periods were also 

studied: 2020 and 2030. Multiple scenarios were analyzed for FACT3, representing 

alternative combinations of time period, ATC improvements, and infrastructure 

improvements. 

Current FAA plans for NextGen (such as the NextGen Implementation Plan) show many 

NextGen operational improvements implemented through the end of the decade. For 

FACT3, the 2020 scenarios in the analysis reflect different levels of NextGen 

implementation:

 “Near-term” NextGen, which includes those operational improvements which have been 

implemented or are expected to be implemented in the next 2 or 3 years; and

 “Midterm” NextGen, which includes all other operational improvements expected to be 

implemented before 2020.

The 2030 time period represents the “far term” in the analysis, allowing more time for 

demand to increase and stress planned airport capacity. Such a long look ahead is helpful, 

given the time required to plan, study, approve, and build new runways and implement 

large-scale NAS modernization efforts. 

The effect of these ATC improvements was evaluated with and without separate runway and 

gate improvements. For 2020, these runway improvements consisted of new and extended 

runways at FLL, ORD, and PHL that have been approved by FAA. The 2030 scenarios with 

runway improvements included a new runway at PHL consistent with the approved EIS. 

New runways would have been considered at other airports in 2030 if planning was

sufficiently advanced and the need existed, but no other runway projects were identified.

Airport Selection

There are 3,330 existing airports in the United States that are open to public use according 

to the FAA’s NPIAS report for 2011-2015. The goal of FACT is to identify those airports that 

are expected to be capacity constrained in the future; however, it is impractical to analyze 

all these airports to the required level of detail. Therefore, a screening method was used to 

select candidate airports prior to performing the detailed analysis. 
FACT3: Airport Capacity Needs in the National Airspace System

B-2 January 2015

Candidates for detailed analysis were those public-access airports where excessive delays 

could potentially have a significant impact on the NAS. The following major categories of 

airports were considered:

 Core Airports: 30 commercial service airports that have been identified by FAA as 

having a significant role in the NAS due to their level of operations or passengers.

 Potentially Constrained Commercial Airports: commercial service airports with 

projected traffic growth that may stress their current capacity.

 General Aviation Airports: other airports with a substantial level of traffic, even if 

primarily general aviation, that affect airspace and air traffic in multi airport areas like 

the NYC area and southern California.

In all, 48 airports were included in the FACT3 analysis as shown in Figure B-1.

Figure B-1. Airports Included in the FACT3 Analysis

The list of potentially constrained commercial service airports was determined using a 

multistep process. If the annualized capacity at an airport was more than 125 percent of 

the forecasted demand (in other words, the demand/capacity ratio was 0.8 or below), then 

delays were not expected to be significant and the airport was eliminated from 

consideration. The initial filter used the most conservative assumptions for fleet mix and 

operating procedures to underestimate capacity. Successive filters used more accurate 

capacity estimates, reducing the initial list of 301 airports to 7 candidates for analysis.

A separate analysis focused on general aviation airports and emerging commercial service 

airports in major metropolitan airports to identify additional airports for analysis. Airports 
FACT3: Airport Capacity Needs in the National Airspace System

B-3 January 2015

with a substantial level of traffic, even if primarily general aviation, can affect airspace and 

air traffic in multi airport areas like NYC and southern California.

Demand

The forecast of aviation demand in 2020 and 2030 came from the FAA’s TAF that was 

published in February 2013, which included annual traffic counts by airport for 

Fiscal Years (FY) 2012-2040. 

The ASV analysis was based on annual demand, while the NAS-wide analysis required daily 

traffic schedules. For the daily analysis, 16 days in FY 2011 were selected to represent the 

entire year. The daily schedules on these days were obtained from Traffic Flow 

Management System data. These schedules were then increased to reflect future traffic 

levels while attempting to preserve airline scheduling patterns. General aviation flights 

were also included. The resulting schedules were “trimmed and smoothed”

20 as necessary 

when airport capacity limits restricted hourly demand.

Refined and Expanded Methodology

The FACT2 analysis was based on both ASV and NAS-wide modeling. These remain the 

principal tools used in FACT3, although the methodology has been revised and refined.

The NAS-wide simulations now run much more quickly. This made it possible to simulate 16 

demand days for each alternative scenario versus only two traffic scenarios (“good weather” 

and “bad weather”) for FACT2. This also led to a need for new metrics for determining 

which airports are “capacity constrained.” The FACT2 metrics were based on good weather 

and bad weather delay measures, but the 16 days in FACT3 represented real-world mixtures 

of good weather and bad weather across the airports being modeled.

NAS-wide modeling was also expanded from runways and airspace to include taxiways and 

gates as well. Discussions with airport operators after the publication of FACT2 often 

addressed factors other than runways and ATC that affected airport delays. The operators 

also mentioned taxiway restrictions and limited numbers of terminal gates as common 

causes of delays and inefficiencies. These factors have been added to the NAS-wide model, 

although in a simplified form.

The NAS-wide modeling relies on calculated capacity curves for each airport. In the past, 

these capacity curves have assumed the same mix of aircraft types (with associated 

performance and wake vortex characteristics) or fleet mix across all time periods. FACT3

includes forecasts of future fleet mixes for the first time based on TAF data and projections 

of airline fleets.

 

20“Trimming” refers to the practice of reducing demand when capacity is significantly exceeded over one or more 

hours.
FACT3: Airport Capacity Needs in the National Airspace System

B-4 January 2015 

Modeling 

Annual Service Volume 

The ASV is the yearly demand that results in a given level of average delay in simulated 

operations. The ASV studies are conducted by the Capacity Analysis Group (AJR-G5) at the 

FAA’s William J. Hughes Technical Center using the Runway Delay Simulation Model 

(RDSIM). The ASV analysis considers multiple runway configurations, weighted by the 

annual frequency of occurrence, and utilizes an annual estimation of weather conditions for 

each configuration in its calculation. 

The RDSIM simulations calculate the amount of delay at different levels of traffic. The 

analyst can then determine which traffic level would produce the target level of delay 

(usually by interpolating between the calculated results). Alternatively, the same demanddelay curve can be used to estimate the average annual delay that results for a given 

annual demand. Example ASV curves are shown in Figure B-2. 

Figure B-2. Example ASV Curves 

The process for FLL, ORD, and PHL was slightly different. Rather than conducting a new 

analysis, average annual delays for these airports relied on previously published studies 

conducted as part of the airport Master Plan or EIS. 

NAS-Wide Modeling 

The other technique used to estimate delays was NAS-wide modeling. Projected traffic 

demand schedules and airport capacity information are used as inputs in a simulation of the 

NAS as a whole, thus capturing the interactive effects of delays on flights throughout the 

system. 

2011 Baseline 

Reference Scenario 

Improvements 

Scenario 

Average Delay per Operation (minutes) 
FACT3: Airport Capacity Needs in the National Airspace System

B-5 January 2015 

Airport capacity curves were prepared for each airport for all alternative scenarios using 

MITRE’s runwaySimulator model. Some example curves for different weather conditions are 

shown in Figure B-3. “Airport capacity” as used in this analysis is defined as the average 

number of operations that can be handled in an hour, under conditions of continuous 

demand, while adhering to all relevant ATC rules and procedures. Each capacity curve 

shows the tradeoff between arrivals and departures as the operational mix ranges from 

arrivals only to a balanced mix of arrivals and departures to departures only. Separate 

curves were generated for: visual meteorological conditions (VMC), marginal visual 

meteorological conditions (MMC), and IMC. 

Figure B-3. Example Capacity Curves 

 

Hourly Arrivals 

Hourly Departures 

For certain NextGen operational improvements that allow changes to separations when 

crosswinds are favorable for displacing wake vortices, separate curves were generated for 

favorable and unfavorable wind conditions. 

The capacity curves and daily demand schedules, together with data about the airspace, 

taxiway performance, and airport gate usage, were provided to the NAS-wide model, 

MITRE’s systemwideModeler. This model simulates the progress of individual flights through 

airports, terminal areas, and en route sectors while tracking delays caused by system 

resources that reflect limited airport capacity, congestion, and the impacts of weather. 

Taxiway congestion was estimated through airport-specific formulas that relate total taxi-in 

and taxi-out time to the number of arrivals and departures while taxiing based on historical 

data. 
FACT3: Airport Capacity Needs in the National Airspace System

B-6 January 2015

The gate resource in systemwideModeler tracks gate occupancy as flights arrive and depart 

at each airport. Because accurate gate assignments are not available for 2020, “clusters” of 

perhaps 5 to 10 gates were defined at each airport based on the airline and sometimes on 

the market segment (regional shuttle, domestic, or international). A flight would be 

assigned to a cluster rather than to an individual gate; only when all gates in the cluster 

were occupied would the arrival have to wait. 

For the 2030 scenarios, uncertainties about the numbers of gates at each airport, airline 

location within the terminal, and flight assignment to specific airlines, made it impractical to 

define reasonable gate clusters. Instead, the gate resource simply tracked the number of 

flights at the gates (and thus the minimum required number of gates) over the day.

Identification Criteria

Both the ASV and the NAS-wide models were used to define whether an airport would be 

considered “capacity constrained” in any scenario. At the forecasted level of traffic, an ASV 

delay of 7 minutes per flight or greater identified a potential capacity constraint. In 

addition, the NAS-wide model needed to show a high percentage of hours with high levels of 

delay for either arrivals or departures. A “high level of delay” was defined as the 

90th percentile value seen at the 30 Core airports in the 2011 baseline simulation of 

16 representative days. Only the hours between 0700 and 2259 local time were 

considered. A congested hour at the airport was thus defined as an average arrival delay of 

6.22 minutes per flight or an average departure delay of 6.65 minutes per flight. In order 

to be considered “capacity constrained,” over 30 percent of the hours at the airport between 

0700 and 2259 needed to meet the criteria for either arrival or departure congestion.

Higher values for these criteria were used to identify airports with severe levels of capacity 

concerns. Specifically, the ASV delay criterion was increased to 15 minutes, and the 

percentage of congested hours was increased from 30 percent to 50 percent.

Similarly, lower values for these criteria served to identify airports that were not capacity

constrained but were approaching that condition. An airport fell into this category if the 

ASV delay was 5 minutes or greater or the percentage of congested hours was 20 percent

or greater for either arrivals or departures.

Note that these criteria, as used in FACT3, must not be considered as an FAA definition of 

acceptable delay for the purpose of justifying proposed airport development without prior 

consultation with the FAA’s Office of Airport Planning and Programming, Airport Planning 

and Environmental Division (APP-400).
FACT3: Airport Capacity Needs in the National Airspace System

C-1 January 2015

APPENDIX C: COMPARISON OF FACT1/2/3

METHODOLOGIES

Table C-1: Data and Methodology Comparison

FACT1 FACT2 FACT3

Timeframe

Base Year 2002 2005 2011

Middle-Term 2013 2015 2020

Far-Term 2020 2025 2030

Demand Forecast

TAF version March 2003 March 2006 January 2013

(32% fewer operations at Core 

airports in 2025 than FACT2)

FATE Forecast 2003 2005 TAF-M with FATE 

methodology planned for use 

in sensitivity analyses when 

available

Scenario Days 1 2 (good and

bad weather)

16 with mixed weather; 

aligned to ATO demand days 

with trimming

Fleet Mix Current/Constant Current/Constant Evolves in future years; 

aligned to FAA APO Fleet 

Forecast

Future NAS Technology

Interim OEP v.5.0 OEP v.8.0 NSIP Segment A with 

adjustments

Long Term Aggressive assumptions NextGen (early) 

assumptions

NSIP Segment B with 

adjustments

Airports 

Primary Airports OEP 35 OEP 35 30 Core

Additional Airports 21 21 18 (including general aviation)

Models and Metrics

NAS Components Runways Runways Runways, 

plus gate-to-gate with general 

constraints of airspace, 

taxiways, and gates

ASV ASV average delay ASV average delay ASV average delay

NAS-Wide 

Simulation:

Arrival Delay Expanded Delay Metrics NAS arrival/departure delay, 

congested hours, throughput
FACT3: Airport Capacity Needs in the National Airspace System

D-1 January 2015

APPENDIX D: SENSITIVITY ANALYSIS OF THE 2013 TAF 

ON FACT3 RESULTS

The FACT3 analysis of expected airport constraints in 2020 and 2030 was based on the 

demand forecasts contained in the 2012 TAF, released in March 2013. Since the analysis 

was completed, FAA published a new version of the TAF in January 2014 (known as the 

2013 TAF). Although most airports had only minor changes in forecasted 2020 and 2030 

demand, the updated forecast did contain substantial demand changes at a few airports.

This appendix presents an estimate of the potential changes to the FACT3 results if the 

forecasts in the 2013 TAF had been used. The results described below were estimated 

based on previous simulations without rerunning the NAS-wide model.

Overview of the 2013 TAF

The FAA releases a new TAF annually. The initial phase in developing a TAF is to update the 

forecast of passenger demand at each airport based on the latest data. Next, a forecast of 

aircraft operations is generated using the passenger forecast and current operational trends. 

Thus, a particular airport’s operational forecast may change from a single year to the next if

the:

 passenger forecast at the airport has changed;

 market served by individual airlines changes; or

 expected operational outlook (such as fleet mix and load factors) at the airport has 

changed.

Figure D-1 shows the difference between the 2013 TAF and 2012 TAF forecasts for 2020 

and 2030 at the 30 Core airports.

Comparing the 2013 TAF to the 2012 TAF, BOS showed the largest increase in expected 

operations with a 17.7 percent increase over the previous 2020 forecast and a 29.2 percent

increase over the previous 2030 forecast. On the other hand, MEM had the largest decrease

compared to the previous 2020 forecast at -21.2 percent, and MCO had the largest decrease 

for 2030 at -13.8 percent. However, some Core airports had very little change between the 

2012 TAF and 2013 TAF: For example, BWI and LGA had less than 0.2 percent change in 

their 2020 and 2030 operational forecasts.

Considering only the constrained airports from the FACT3 analysis, the following substantial 

changes were seen in the 2013 TAF:

 EWR increased 7.5 percent in 2020 and 14.2 percent in 2030

 JFK decreased 5.0 percent in 2020 and 8.7 percent in 2030

 LAS decreased 5.8 percent in 2030

 IAH decreased 7.5 percent in 2030

 PHX decreased 7.3 percent in 2030
FACT3: Airport Capacity Needs in the National Airspace System

D-2 January 2015

Figure D-1. Change in Forecasted Demand (2013 TAF vs. 2012 TAF)

Methodology for Estimating Effect of Demand Changes on FACT3

Results

Does the new forecast in the 2013 TAF change the results of the FACT3 analysis for an 

airport? 

In some cases, the answer is straightforward. If an airport had been identified as needing 

additional capacity and the forecasted traffic level increased in the 2013 TAF, then the 

airport will still need more capacity. The converse is also true.

At most airports, it was necessary to estimate the effect of the new TAF on the original 

analysis. Two different methodologies, the ASV and the NAS-wide simulation, were used in 

FACT3 to estimate future delays. Both analyses were reviewed for this sensitivity analysis.

The ASV analysis produces a curve of average annual delay versus annual traffic (see the 

example in Figure B-2). Changing the forecast simply requires moving to a different part of 

the curve to obtain the new value for average delay.
FACT3: Airport Capacity Needs in the National Airspace System

D-3 January 2015

Rerunning the NAS-wide analysis with the new forecast would be considerably more 

difficult, since this analysis would require new daily traffic schedules for 2020 and 2030 at

each airport. Rather than rerun the NAS-wide simulations, an alternative approach was 

used to estimate the effect of the new forecasts. While the FACT3 results in this report had 

been produced using the NAS-wide model and the 2012 TAF demand; the model had also 

been run earlier using 2011 TAF demand forecasts. The interpolation between these two 

demand levels is used to estimate the potential effect of the 2013 TAF on future airport 

congestion.

This interpolation does not provide exact results, but it can provide a reasonable estimate of 

the number of congested hours if the 2013 TAF demand is between or close to either the 

2011 TAF or 2012 TAF demand projections. Together with the new average annual delay 

from the ASV analysis, this NAS-wide interpolation greatly reduced the uncertainty around 

the potential effects of the 2013 TAF on the FACT results.

Potential Effect of the 2013 TAF

For each airport and future scenario, the potential status was determined using the updated 

ASV delay values and an estimate of the NAS-wide congested hours. The results of this 

reassessment are summarized in Tables D-1 and D-2 for 2020 and 2030, respectively. 

Substantial uncertainty about the potential status is indicated in the chart by a question 

mark (“?”).

Table D-1. Sensitivity Analysis Results for 2020 Scenarios

Airports Needing Additional 

Capacity

Reference Improvements

2012 TAF 2013 TAF 2012 TAF 2013 TAF

ATL Hartsfield-Jackson Atlanta Int’l  n/c  n/c

EWR Newark Liberty Int’l  n/c  n/c

JFK John F. Kennedy Int’l  n/c  n/c

LGA LaGuardia  n/c  n/c

PHL Philadelphia Int’l  n/c  n/c

SFO San Francisco Int’l  - - n/c

 = Capacity constrained or severe status

n/c = No change to designation

? = Uncertain

- = Not capacity constrained
FACT3: Airport Capacity Needs in the National Airspace System

D-4 January 2015

Table D-2. Sensitivity Analysis Results for 2030 Scenarios

Airports Needing Additional 

Capacity

Reference Improvements

2012 TAF 2013 TAF 2012 TAF 2013 TAF

ATL Hartsfield-Jackson Atlanta Int’l  n/c  n/c

BOS Boston Logan Int’l -  - 

CLT Charlotte Douglas Int’l  n/c  -

DFW Dallas-Ft. Worth Int’l -  - 

EWR Newark Liberty Int’l  n/c  n/c

FLL Fort Lauderdale/Hollywood Int’l  n/c n/c

IAH George Bush 

Intercontinental/Houston 

n/c n/c

JFK John F. Kennedy Int’l  n/c  n/c

LAS McCarran Int’l  n/c  n/c

LGA LaGuardia  n/c  n/c

ORD O’Hare Int’l  n/c - n/c

PHL Philadelphia Int’l  n/c - n/c

PHX Phoenix Sky Harbor Int’l  ?  ?

SFO San Francisco Int’l  n/c  n/c

 = Capacity constrained or severe status

n/c = No change to designation

? = Uncertain

- = Not capacity constrained

Overall, most of the airports that are identified by FACT3 as constrained in 2020 or 2030, 

when using the 2012 TAF, remain unchanged when the 2013 TAF is considered. This is 

particularly true for the 2020 scenarios. Since these airports are likely to be capacityconstrained under a variety of demand scenarios, this underscores the rationale to focus on 

solutions at these airports.

2020 Reference Scenario

The 2013 TAF shows a pattern of greater concentration of demand at many airports that are 

currently busy, including ATL and EWR. Both airports had previously been identified as 

needing more capacity in 2020 in the Reference scenario. Since their 2020 demand 

increases in the 2013 TAF, ATL and EWR would still need more capacity. JFK and PHL would 

still be identified as needing more capacity even though their forecasted demand for 2020 

declines slightly in the 2013 TAF. Demand at LGA is virtually unchanged, given the 

constrained forecast used in the TAF; accordingly, its status does not change. 

On the other hand, the decline in forecasted 2020 demand at SFO reduces the expected 

delays at the airport. As a result, SFO may not meet the criteria for a constrained airport.

2020 Improvements Scenario

Even though the 2020 forecast in the 2013 TAF has changed, the difference does not affect 

the list of airports expected to need additional capacity with the improvements scenario 

(i.e., midterm NextGen and runway improvements). These improvements would reduce 

delays at ATL and EWR so they would no longer be considered severely congested, despite 

higher traffic levels. JFK would not be expected to be severely delayed either due to the 

reduction in the 2020 forecast. The status of LGA and PHL does not change with the new 
FACT3: Airport Capacity Needs in the National Airspace System

D-5 January 2015

forecast. SFO was not identified as capacity constrained in this scenario at 2012 TAF 

demand levels nor at the slightly lower demand level in the 2013 TAF.

2030 Reference Scenario

Several airports that had been identified as severely congested in the 2030 Reference 

Scenario are still expected to be severely congested, as their 2030 demand levels stay the 

same, decline only slightly, or increase in the 2013 TAF. These airports include ATL, EWR, 

JFK, LGA, ORD, PHL, and SFO.

Other airports with lower forecasts in the 2013 TAF would still be capacity constrained but 

not severely so. This includes CLT, FLL, IAH, and LAS. PHX also has a lower forecast but its 

status is uncertain. 

On the other hand, BOS and DFW are expected to be constrained at the 2013 TAF demand 

levels and would no longer be in the caution category. 

2030 Improvements Scenario

Given the demand increases at ATL, EWR, and SFO in the 2013 TAF, these airports would 

still be expected to be severely congested. JFK would also be expected to be severely

congested despite a reduced demand forecast. LGA would be unchanged.

IAH, LAS, and perhaps PHX would be constrained in 2030 even with a lower demand 

forecast. CLT would no longer be considered a constrained airport due to the decrease in 

the demand forecast but would remain in the caution category.

BOS and DFW would continue to be capacity constrained even with the planned 

improvements due to the higher demand forecasts at those airports. 

Due to runway development underway or planned at FLL, ORD, and PHL, these airports will 

no longer meet the FACT3 criteria to be capacity constrained under either the 2012 or 2013 

TAF demand level.