OFF CI E OF SYSTEM CAPA

C

ITY

AND REQUIREMENTS

Federal Aviation Administration

Office of System Capacity

and Requirements

Aviation

System

Capacity

Annual Report

Expand to Meet Demand
[ 2 ]

CONTENTS

Letter from the Director..................................................................................................... 3

Introduction ...................................................................................................................... 4

Airport Development ......................................................................................................... 6

Airspace Development..................................................................................................... 10

Development of New Instrument Approach Procedures................................................... 13

Developments in Aviation Weather .................................................................................. 18

Plans for the Future ......................................................................................................... 20

Miscellaneous .................................................................................................................. 22

Footnotes ........................................................................................................................ 23
[ 3 ]

LETTER FROM THE DIRECTOR

We in the Office of System Capacity and

Requirements (ASC) are working to identify, develop, and implement initiatives that have the

potential to increase the capacity of the national

aviation system.

In the Capacity Office, we are well aware of

the importance of our job and of the need for

the entire aviation community to work together

so that we can accommodate current and projected air traffic demand at our airports with a

minimum of delay and without compromising

safety or environmental considerations.

As we all know, aircraft delays cost the airlines and their passengers many millions of dollars each year. Looking beyond the recent dip in

demand for air travel, the current FAA forecasts

project that passenger enplanements and aircraft

operations will grow at steady rates for the foreseeable future. As the number of aircraft operations increases to meet that demand, delays will

also increase, unless improvements are made to

aviation system capacity.

Expanding capacity requires an integrated,

systematic approach that develops capacityproducing improvements throughout the aviation system. Included in these efforts are airport

developments, terminal and en route airspace

improvements, enhanced air traffic control procedures, improved weather detection and dissemination, and the application of new technologies. We are developing this integrated approach with emphasis on four major areas: airport capacity, airspace capacity, approach procedures, and weather.

The Capacity Office currently produces several recurring reports.

• The Aviation System Capacity Plan is published annually and, in addition to providing

airport delay statistics, serves to identify programs that have potential for increasing capacity and reducing delay.

• Airport Capacity Enhancement Plans report

the results and recommendations of Airport

Capacity Design Team studies at individual

airports. Over 25 of these plans have been

published.

• Capacity Initiatives pamphlets describe improvements in air traffic control procedures

that have recently become available or will

be available in the next three to five years.

All of these reports, however, tend to concentrate on the future and describe potential capacity-producing initiatives. Until now, we have

not developed a publication that reports on our

accomplishments. That is the purpose of this

new report. We are calling it an Annual Report

because, like the annual reports in the corporate

world, it highlights our recent accomplishments

and provides some insight into our plans for the

future. After a brief introduction, the report will

discuss airport development, airspace development, development of new instrument approach

procedures, and developments in aviation

weather.

We seek innovative solutions to delay problems, and we want to work as closely as possible

within the FAA and with the aviation community to attain our stated goal: expand the capacity of the aviation system so that it is ready to

meet projected increases in demand.

Edward T. Harris

Director, Office of System

Capacity and Requirements

October 1993
[ 4 ]

Over the long term, the demand for commercial aviation service has been growing

steadily, and this steady growth is expected to

continue in spite of the recent dip in the demand for air travel.

Growth in demand, as measured by passenger enplanements, is related to growth in the

gross domestic product (GDP, the value of all

goods and services produced). Forecasts indicate

that both GDP and passenger enplanements will

continue to grow at steady rates for the foreseeable future.1

As demand continues to grow, the burden

placed on the national aviation system increases

accordingly.

INTRODUCTION

Night operations at Raleigh-Durham International Airport.

Forecasts indicate that passenger enplanements will

continue to grow for the foreseeable future.

Until the early 1980’s, the infrastructure of

our national aviation system, including its

airports and air traffic control system, kept

abreast of demand. By the mid 80’s, however,

airports were having increasing difficulty keeping pace with the sharply accelerating traffic

growth, particularly those serving major metropolitan areas on the east and west coasts. At our

busiest airports, serious congestion problems

have become commonplace.

Growth in Gross Domestic Product and Passenger

Enplanements, 1964 to 2004

$0

$1.0

$2.0

$3.0

$4.0

$5.0

$6.0

$7.0

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

Gross Domestic Product (trillions of 1987 $)

Enplanements (000)

Calendar Year

⇐ Historical Forecast ⇒

Enplanements (000)

Gross Domestic Product (1987 dollars)

1964 1968 1972 1976 1980 1984 1988 1992 1996 2000 2004
[ 5 ]

CAPACITY AND DELAYS

The aviation system capacity problem is

most often described in terms of aircraft flight

delays. When the capacity of an airport or the

en route airspace is reached or exceeded, flight

delays are the result.

Capacity and delay are generally determined

by one or more conditions, including weather,

mix and volume of aircraft traffic, capacity of

current runway configurations, and limitations

or rare outages in airfield and air traffic control

equipment. Weather is the most significant of

these factors.

THE COST OF DELAYS

One problem with delay as a measure of

capacity is perceptions. Mention an average

delay of 10 minutes per operation to typical

airline passengers at an airport, and they would

probably consider themselves lucky to have

arrived or departed so close to their scheduled

times. Mention this same delay to aviation

professionals, and they would immediately

recognize an airport with a capacity problem.

In fact, a few minutes of airport delay at the

beginning and end of every flight add up to

billions of dollars of increased costs to the airline

industry, the flying public, and the Federal

government.

At a typical large hub airport like SeattleTacoma International, which has about 350,000

operations per year, an average delay of 10

minutes per operation would mean more than

58,000 hours of delay per year. At

an estimated $1,600 per hour in

aircraft direct operating costs2, an

average delay of this size would

cost the airlines over $93 million

per year at this airport alone.

In 1991, 23 of the country’s

largest airports each experienced

more than 20,000 hours of annual

aircraft flight delays. By 2002, we

expect such serious delays at 10

more of our airports if no improvements in capacity are made.

With an average aircraft direct

operating cost of $1,600, each of

these airports could incur a

minimum of $32 million of delay,

for a total cost to the airlines of at

least $1.1 billion in 2001.

A few minutes of delay at the beginning and end of each flight

add up to billions of dollars in annual delay costs.

Class 1 Class 2 Class 3 Class 4

Single-engine prop 

under 12,500 lbs.

Twin-engine prop 

under 12,500 lbs.

Large aircraft under 300,000 lbs. 

and small jet aircraft

Heavy aircraft over 

300,000 lbs.

$42 per hour

$124 per hour

$1,607 per hour

$4,575 per hour

Aircraft Direct Operating Costs

(1987 dollars)
[ 6 ]

Constructing new airports or new taxiways,

ramps, runways, and runway extensions at existing airports are the obvious and most direct

actions that can be taken to improve capacity.

New airports take many years to evolve from

planning through development to actual operations.

The challenge for the aviation community is

to maximize existing airport facilities to meet

near-term demand while at the same time

developing the new facilities needed to meet

future demand.

Environmental, financial, and other factors

have restricted the development of new airports.

Denver International Airport (DIA) is the only

major new air carrier airport now under construction. An increased emphasis has been

placed on the redevelopment and expansion of

existing airport facilities. However, site restrictions, airspace considerations, or concerns about

environmental issues often make expansion of

existing airports difficult if not impossible.

Constructing new airports, implementing joint

civilian and military use of military airfields,

converting closed military facilities to civilian

use, and developing regional airport systems are

all possible alternatives. A number of planning

studies are underway in major metropolitan

areas where additional airport capacity is

AIRPORT DEVELOPMENT

New airfield construction projects are the most

direct actions to improve capacity.

Denver International Airport (DIA) — 10 years in the making

needed, such as Boston, Chicago, Seattle, and

San Diego.

AIRPORT CAPACITY DESIGN TEAMS

The Capacity Office works closely with

Airports at the FAA and with the Airports

Divisions at the FAA’s Regional Headquarters.

Since 1985, the FAA has sponsored a program of

Airport Capacity Design Teams at major airports throughout the U.S. These teams are composed of FAA personnel, airport operators, air

carriers, other airport users, and aviation industry representatives. Each Capacity Team makes

use of local and national expertise to identify

and evaluate alternatives to enhance existing

airport and airspace capacity. The recommendations

developed by the Capacity

Teams deal with airfield,

facilities and equipment,

and operational improvements. Alternatives are

examined with the assistance of computer simulations provided by the FAA

Technical Center in Atlantic City, NJ.
[ 7 ]

20 projects have been recommended to add

second, third, and fourth parallel runways.

• New taxiways to expedite the flow of ground

traffic and ease congestion. Capacity Teams

have recommended new taxiway construction at 16 airports.

• Runway and taxiway extensions, holding

areas/pads, and improved runway exits to

decrease runway occupancy times and

increase runway availability. Nearly 70 of

these projects have been recommended at

the airports studied to date.

• Improvements in precision landing system

equipment to reduce visibility minimums

and help to maintain capacity as the weather

deteriorates. Over 34 of these projects have

been recommended by the Capacity Teams.

• Implementation of improved air traffic

control (ATC) procedures designed to provide additional arrival and departure capacity. Capacity Teams have made over 50

recommendations for a variety of ATC

improvements.

Since the start of the

program, over 35 Airport Capacity Design

Teams have either

completed their studies

or have work in progress.

A typical Capacity

Team makes 20 or more

recommendations for

capacity improvements

at a specific airport. To

date, the Airport Capacity Design Teams have

made over 500 capacityproducing recommendations. The biggest

capacity gains result

from the synergistic

effect of combining recommended improvements to

the airfield with recommended improvements for new facilities and

equipment and improved approach procedures.

For example, Capacity Design Teams can

recommend:

• Additional parallel runways to ease arrival

and departure congestion. A second independent parallel runway can provide as

much as a 100 percent gain in capacity. Over

Cuba

Florida

Puerto

Rico

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HNL

Guam

ATL

BNA

CLE

FLL

IAD

LAX

MCI

MCO

MDW

MEM

MIA

MSY

OAK

ORD PHL

PHX

PIT

RDU

SAT

SEA

SFO

SJC

SLC

STL

DTW

BOS

CMH

IND

MSP

ABQ

CLT

IAH

RIC ORF

PHF } Eastern Virginia

(RIC, ORF, PHF)

Completed

Ongoing

LAS

DFW

Airport Capacity Design Teams are composed of FAA

personnel, airport operators, air carriers, other airport

users, and aviation industry representatives.

Airport Capacity Design Teams in the U.S.
[ 8 ]

Improvements recommended by the Capacity Teams become part of the master planning

process at the airports and will be implemented

when needed to meet demand. Many of the

airports studied have already begun or completed construction of recommended improvements.

CAPACITY ENHANCEMENT PROJECTS UNDER

CONSTRUCTION OR COMPLETED

The following are examples of projects

recommended by Capacity Teams that are now

under construction or have been completed and

should provide significant savings in delay costs.

Charlotte/Douglas International Airport

An extension of Runway 36R is under

construction. The extension will permit the

concurrent use of Runway 5 for departures while

traffic is arriving on Runway 36. Planned angled

taxiways on Runway 18L will reduce runway

occupancy time to increase arrivals and speed up

surface flow. The installation of ASDE would

also enhance safety and facilitate better management of surface flow to reduce congestion in

poor weather.

The extension of Runway 36R is expected to

save nearly 3,300 hours and $4.6 million in

annual delay costs3 when the airport reaches

520,000 aircraft operations per year. At 600,000

annual aircraft operations, the new taxiway is

expected to save 9,200 hours and $12.9 million

each year.

Atlanta-Hartsfield International Airport

A new taxiway is now under construction

parallel to an existing taxiway, which is currently

the only route between the north and south

runway complexes. The additional taxiway will

reduce congestion by allowing simultaneous

two-way traffic and, with the installation of

Airport Surface Detection Equipment (ASDE),

will enhance safety and improve ground operations during poor visibility.

Chicago Midway Airport

Midway’s unique location within an urban

metropolitan area where space is at a premium

severely limits its physical expansion. The

Design Team was challenged to develop initiatives that would work within the current confines of the airfield. The conversion of Taxiway

R into Runway 13L/31R for general aviation

aircraft allows for the segregation of slower

traffic from air carrier traffic and accelerates

arrival and departure streams. The rehabilitation

of Runway 13C/31C coupled with the extension

of Runway 22L has produced results similar to

building a new runway. Ground and air traffic

flows have been increased and are near maximum.

Detroit Metropolitan Wayne County Airport

An independent crosswind runway recommended in Detroit’s 1988 Capacity Team study

is under construction and should be completed

Charlotte/Douglas International Airport. by late 1993. Recommendations from that study

18R

18L

36L 36R

18W

36W

18E

36E

Old Terminal

Building

Air Carrier

Building

GA Ramp

U.S. Customs

Control Tower

⇐ 10,000 ft. ⇒

⇐ 7,501 ft. ⇒

⇐ 7,845 ft. ⇒

2,500 ft. 1,200 ft. 3,000 ft. - 

4,300 ft.

36W 36W

18W 18W

1,000 ft.

5,000 ft.

Three Independent IFR Arrival Streams OptionThree IFR Arrival Streams (one dependent) OptionTwo IFR Arrival Streams Option

2,500 ft.

Taxiway D

Taxiway C

Taxiway M

Taxiway A

Taxiway E

Taxiway M

Taxiway A

Taxiway M

Taxiway A

Taxiway C

5

23
[ 9 ]

provided a series of runway, taxiway, and holding-apron improvements for a substantial

increase in surface traffic efficiency that allowed

for a successful expansion of the main terminal.

The new crosswind runway is expected to

save 54,990 hours and $85.3 million in annual

delay costs4 when the airport reaches 409,000

aircraft operations per year. At 500,000 annual

operations, the new runway is expected to save

104,930 hours and $173.1 million each year.

In the continuing effort to meet everchanging capacity needs, Detroit is being

considered as the first in a series of Capacity

Team follow-up studies at selected airports.

Nashville International Airport

The extension and relocation of Runway 2C

is currently under construction. The runway will

be moved 400 feet to the west, and its length

will be extended to 8,000 feet. This will increase

flexibility for arrival and departure operations in

conjunction with Runway 2L. It will also allow

for a separate apron-edge taxiway for general

aviation aircraft (GA) adjacent to the GA ramp.

The new Runway 2C is expected to save

nearly 3,000 hours and $2.9 million in annual

delay costs6 when the airport reaches 417,500

aircraft operations per year. At 534,000 annual

aircraft operations, the new runway is expected

to save 7,600 hours and $7.6 million each year.

Phoenix Sky Harbor International Airport

The completion of a new crossover taxiway

between the two parallel runways has expedited

the flow of ground traffic to and from the

terminals and the north and south runway

complexes. In addition, a series of taxiway and

exit improvements, which included run-up/hold

pads, a holding area, widened fillets, and angled

exits, has reduced congestion and runway

occupancy times and improved the efficiency of

traffic flow throughout the airport

The new crossover taxiway is expected to

save about 3,400 hours and $3.7 million in

annual delay costs5 at 465,000 aircraft operations per year. At 550,000 operations, the new

taxiway is expected to save 11,000 hours and

$11.9 million each year.

Orlando International Airport

A series of taxiway improvements have

provided a bypass capability and improved the

flow of ground traffic between the east and west

sides of the airfield. In addition, a fourth parallel

runway is currently under construction.

The new runway is expected to save $1.4

million in annual delay costs7 at 400,000 aircraft

operations per year. When the airport reaches

600,000 annual aircraft operations, the new

runway is expected to save $47.3 million each

year. Procedures for triple parallel approaches

were published in May 1993. The use of three

simultaneous (independent) arrival streams is

expected to save an additional $10.8 million at

400,000 operations per year and $74.0 million at

600,000 operations per year.

Nashville International Airport.

A-3

R-1

R-5

R-4

R-3

R-2

A

R-1

A-4

A-5

B-1

E-1

G-9

E-3

E-2

E-4

E E

G-5

G-6

B

B

B

B-4

B-3

B-2

B-2A

T-1

T-2

T-4

T-5

L-1

L-2

L-3

L-4

L-5

L-6

L L L

C-9

C-8

C-7

C-5

C-4

C-3

C-2

C

C

C

A

A

A

2R 2L

20R

20L

20C

2C

13

31

Donelson Pike

1,500 - 2,500 ft.

T-6

1,000 ft.

⇐ 1,300 ft. ⇒

1,000 ft.

1,000 ft.

⇐ Existing 5,186 ft. ⇒

1,000 ft.

5,000 ft.

⇐ Relocation and extension to 8,000 ft. ⇒

⇐ 8,000 ft. ⇒

⇐ 10,000 ft. ⇒

⇐ 8,500 ft. ⇒

⇐ 7,702 ft. ⇒

700 ft.

Air National Guard

General 

Aviation
[ 10 ]

Our efforts to improve airport capacity will

not be completely effective unless the terminal

and en route airspace can handle the increased

traffic. Since 1986, we in the Office of System

Capacity and Requirements have been applying

the FAA’s Airport and Airspace Simulation

Model (SIMMOD) to large-scale airspace redesign issues. This airspace capacity design program is intended to identify and evaluate operational alternatives that have the potential to

improve efficiency, increase capacity, reduce

delay, and maintain or improve the current level

of safety.

Airspace capacity studies have been completed or are underway at 20 major areas in the

U.S. The following are examples of completed

studies and of the airspace modifications that

have been evaluated in these studies.

AIRSPACE DEVELOPMENT

NEW YORK AIRSPACE CAPACITY PROJECT

The recently completed New York study

is the most ambitious

airspace analysis project

undertaken to date. It

analyzed air traffic

operations within the

New York Air Route

Traffic Control Center

(ARTCC) and portions

of the Boston, Cleveland, and Washington

Centers and included

data from 18 approach

controls and 86 en route

sectors. The study

focused on proposed

airspace restructuring

and sector altitude

modifications aimed at

relieving the complexity

and saturation of air traffic operations. It also

examined new south arrival and departure

routing for Stewart International Airport to

support potential future traffic growth and

determine the effects on traffic loading.

SIMMOD was used to evaluate proposed operational alternatives, such as establishing a new air

traffic controller position, rerouting flights to

new sectors based on destination or aircraft

type, and changing sector boundaries and

altitudes. The results from SIMMOD provide

data on traffic loading, controller workload, and

delay time. As an example, the resectorization of

New York Center Area D could potentially save

$7.6 million in delay costs each year at the

current levels of demand and as much as $71.2

million per year at the demand levels forecast for

the year 2003.†

Northeast oblique view of radar flight tracks traversing

New York Center’s Area D in a single day.
[ 11 ]

OTHER EXAMPLES OF COMPLETED STUDIES

Kansas City Airspace Capacity Project

This study analyzed airspace improvements

proposed for the Kansas City ARTCC. The

analysis evaluated capacity and delay effects

associated with relocating arrival fixes based on

a four-cornerpost operation, implementing dual

arrival routes, and developing new departure

routes for the St. Louis Terminal Radar Approach Control (TRACON). The annual delay

cost savings†

 for these airspace realignments

would be $7 million at the baseline level of

operations and $68 million when the level of

operations increases by 22 percent. The study

also evaluated airport and airspace improvements proposed for the Kansas City TRACON to

increase capacity at Kansas City International

Airport. A third part of the study analyzed

modifications to align Kansas City ARTCC

traffic flows with the arrival and departure

changes made in the St. Louis and Kansas City

TRACONS.

Houston/Austin Airspace Project

The purpose of this study

was to evaluate quantitatively

the effect of proposed

operational alternatives in

the Houston and Fort

Worth ARTCCS, terminal

airspace operations in the

Austin TRACON, and

airfield operations at the

existing Robert Mueller

Airport and at the proposed

new Manor Airport8 in Austin. Delay-cost savings were estimated for

these changes under two assumptions, that

Austin would become a hub airport and that it

would not. At the traffic levels forecast for the

year 2000, the proposed airspace realignments

would save $19 million per year for non-hub

operations and $71 million per year for hub

operations.†

Oakland Airspace Project

The Oakland project evaluated the capacity

and delay impacts of proposed operational

alternatives within the Oakland ARTCC, the Bay

and Sacramento TRACONS, and the San Francisco, Oakland, San Jose, and Sacramento

airports. The study included an evaluation of air

traffic operations under a proposed Northern

California Metroplex Control Facility, which

would consolidate operations in the Bay, Sacramento, Stockton, and Travis approach controls.

The annual delay cost savings with this redesign

and consolidation of airspace, along with a

proposed runway extension at San Jose, would

be $45.9 million at the demand levels forecast

for the year 2000.†

Dallas-Fort Worth Metroplex Project

This project focused on an evaluation of a

new airspace design for the Dallas-Ft. Worth

Metroplex, an assessment of alternatives for

providing and utilizing new runway capacity at

Dallas-Ft. Worth International Airport, and an

evaluation of the capacity and delay impacts of

airspace interactions among

Continental U.S. Air Route Traffic

Control Centers (ARTCCs).

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[ 12 ]

traffic from various airports in the Metroplex

area. The annual delay cost savings with the

redesign of the airspace would be $32 million at

the demand levels forecast for the year 2000.†

Los Angeles Airspace Project

This study concentrated on a capacity

analysis of Los Angeles International Airport, a

delay analysis of airspace choke-points in the

Los Angeles ARTCC, and an analysis of an

airspace realignment in the Los Angeles Basin.

With the redesign of airspace, the delay cost

savings would be $23 million per year with a

nominal growth in demand level forecast for the

year 2000.†

Jacksonville Airspace Capacity Project

This study analyzed air traffic operations in

the Jacksonville ARTCC under proposed airspace

and route modifications, adjusted sector altitude

limits, and a variety of projected traffic levels.

The impact of a proposed expansion of a military operating area would result in an annual

cost penalty of $121 million at the demand

levels forecast for 2003.†

 The ability to use dual

arrival and segregated departure routes under

the proposed Orlando TRACON realignment

would result in an annual delay savings of $13

million at the same demand levels.

THE NEED FOR AN INTEGRATED APPROACH

The airspace design projects completed to

date have identified tens of millions of dollars in

delay savings, and the vast majority of the

airspace modifications evaluated in these studies

either have been or are being implemented.

The airspace capacity design effort has also

served to emphasize the “system” nature of the

delay problem and the need for an integrated

approach that coordinates the development of

capacity-producing alternatives. Airfield improvements, enhanced air traffic control procedures, and improvements in terminal and en

route airspace are frequently interrelated —

changes in one require changes in the others

before all of the potential capacity benefits are

realized.
[ 13 ]

Over half of all delays are caused by adverse

weather conditions. These delays are largely the

result of instrument approach procedures that

are much more restrictive than the visual procedures in effect during better weather conditions.

The FAA continues to install new instrument

landing systems (ILSs) and upgrade existing

systems to support continued operations during

reduced visibility. In the past few years, the FAA

has developed new, capacity-enhancing instrument approach procedures for use under instrument meteorological conditions (IMC) to take

advantage of improving technology while

maintaining or improving the current level of

safety. The goal is to have capacity during IMC

equal capacity during visual meteorological

conditions (VMC).

Publication of these procedures and development of new procedures is the result of a

cooperative effort among Air Traffic, Flight

Standards, Research and Development, Aviation Standards, and the Capacity Office.

RECENT NATIONAL STANDARDS

Several new national standards have been

published that incorporate some of these capacity-enhancing approach procedures.

• Simultaneous (independent) parallel approaches using the Precision Runway Monitor (PRM) to runways separated by 3,400 to

4,300 feet. The average capacity gain expected from this improvement is 12 to 17

arrivals per hour. PRMs are currently scheduled for installation at Raleigh-Durham,

Minneapolis, Memphis, Atlanta, and Baltimore.

National standard published November

1991. The first PRM was commissioned at

Raleigh-Durham on June 30, 1993.

• Improved dependent parallel approaches to

runways separated by 2,500 to 4,300 feet

that reduce the required diagonal separation

from 2.0 to 1.5 nautical miles. The average

capacity gain expected from this improvement is 4 arrivals per hour. Of the busiest

100 airports in the country, 22 may benefit

from this improved procedure.

National standard published June 1992.

• Reduced longitudinal separation on wet

runways from 3 to 2.5 nautical miles inside

the final approach fix (FAF). The average

DEVELOPMENT OF NEW INSTRUMENT APPROACH PROCEDURES

The PRM provides more frequent updates of aircraft positions.

2,500 - 4,300 ft.

2.88 nm

1.5 nm 1.5 nm 1.5 nm

2,500 - 4,300 ft.

3.91 nm

2 nm 2 nm

Improved separation for dependent parallel ILS operations.
[ 14 ]

capacity gain expected from this improvement is 3 to 5 arrivals per hour. Of the

busiest 100 airports in the country, 22 may

benefit from this improved procedure.

National standard published June 1992.

• Dependent Converging Instrument Approaches (DCIA) using the Converging

Runway Display Aid (CRDA). The CRDA

update to the ARTS IIIa software projects an

electronic “ghost” image of aircraft on

converging arrival paths so that separation

between aircraft can be verified by the

controller during arrival spacing. The average capacity gain expected from this improvement is 10 arrivals per hour. Of the

busiest 100 airports in the country, 40 may

benefit from this improved procedure.

National standard published November

1992.

• Triple independent parallel approaches using

current radar systems (4.8 second update

rates) to runways separated by as little as

5,000 feet at airports whose field elevation is

less than 1,000 feet. The use of triple approaches under IFR could result in a 50

percent increase in arrival capacity compared

to dual independent approaches. Of the

busiest 100 airports in the country, 6 may

benefit from this improved procedure.

National standard published May 1993.

IMPROVED APPROACH PROCEDURES

UNDER DEVELOPMENT

New approach procedures continue to be

developed to enhance operations and improve

system performance. These new procedures are

designed to provide additional capacity at

existing airports, while maintaining or improving the current level of safety in aircraft operations. The testing of these initiatives is thorough

and involves various validation methods, including real-time simulations and live demonstrations at selected airports.

• Flight Management System (FMS) transition to existing approaches. Use of FMS

computers to transition aircraft from the en

route phase of flight to existing charted

visual flight procedures (CVFP) and ILS

approaches has been demonstrated at San

Francisco International Airport and is now

in regular use there. FMS-assisted flight path

navigation procedures are expected to allow

a reduction in weather minimums and offer

alternative arrival paths for FMS-equipped

aircraft.

2 or 5 nm

2 or 5 nm

Dependent converging IFR approaches using CRDA (ghosting).

The FAA is developing capacity enhancing instrument approach

procedures to take advantage of improving technology.
[ 15 ]

• Simultaneous operations on wet intersecting

runways. Demonstrations have been underway at Boston, Pittsburgh, O’Hare,

Kennedy, Philadelphia, and Miami. At

Chicago’s O’Hare International Airport,

increases of up to 25 percent have been

experienced during wet runway operations.

Of the busiest 100 airports in the country, a

total of 60 conduct hold-short operations

and may benefit from this improved procedure.

• Simultaneous ILS and LDA approaches. Use

of an LDA approach in conjunction with an

ILS approach on adjacent, closely spaced

(700 to 2,500 feet) parallel runways allows

an additional arrival stream in weather

minimums lower than those required for

visual approaches. This procedure has been

in use for several years at St. Louis Lambert

Field and more recently at San Francisco

International Airport. St. Louis has experienced a capacity gain of about 18 arrivals per

hour. Of the busiest 100 airports in the

country, 30 may benefit from this improved

procedure.

• Simultaneous (independent) parallel approaches using the Precision Runway Monitor (PRM) (1 to 2.4 second update rates) to

runways separated by 2,500 to 4,300 feet.

National standards have been published for

independent parallel approaches using PRM

to runways that have centerline separated by

3,400 to 4,300 feet. Simulations for parallel

runways separated by less than 3,400 feet are

being conducted at the FAA Technical

Center to determine the minimum

centerline distance for independent approaches. Of the busiest 100 airports in the

country (based on passenger enplanements),

22 may benefit from this improved procedure.

• Improved operations on parallel runways

separated by less than 2,500 feet. Current air

traffic control procedures consider parallel

runways separated by less than 2,500 feet as

a single runway under IFR. The FAA’s wake

vortex program is investigating ways to

support a reduction in the 2,500 foot requirement under most meteorological

conditions. Reducing the separation required by wake vortex considerations would

improve capacity for both arrivals and

departures. Of the busiest 100 airports in

the country, 47 may benefit from this improved procedure.

• Independent and dependent approaches to

three parallel runways. Airports with spacings from 2,500 to 3,400 feet between one

set of runways and 4,300 feet or more

between the other set are limited to dual

2,500 - 4,300 ft.

No Transgression Zone (NTZ)

Simultaneous parallel instrument approaches using PRM.

700 - 2,500 ft.

ILS

LDA offset 7°

NTZ

4,300 ft.

Simultaneous ILS and LDA approaches.
[ 16 ]

runway operations. These new procedures

would allow triple operations, with dependent operations between the closest set of

parallel runways and independent operations

between the other set. Real-time simulations

of this concept will be scheduled in the

future. Of the busiest 100 airports in the

country, 10 may benefit from this improved

procedure.

• Traffic Alert and Collision Avoidance

System (TCAS) Cockpit Display of Traffic

Information (CDTI) for separation assistance. The cockpit display of traffic information associated with TCAS can provide the

means for flight crews to assist controllers in

providing separation assistance and reducing

the spacing tolerances that are maintained

between aircraft for many phases of flight. A

feasibility study for this new procedure was

published in April 1991. Data gathering is

now underway, and preliminary concept

simulations are being devised to test these

new procedures in an integrated laboratory

environment.

• Independent parallel approaches to runways

separated by as little as 4,000 feet using the

Final Monitor Aid (FMA) and radars with

4.8 second update rates that provide at least

2 milliradian accuracy (such as the MODE S

or monopulse radar system). Real-time

simulations of this new procedure are underway. Of the busiest 100 airports in the

country, 12 may benefit from this improved

procedure.

2,500 ft.

4,300 ft.

1.5 nm separation

NTZ

Independent and dependent parallel approaches.

The improved high-resolution display and computergenerated controller alerts of the Final Monitor Aid (FMA)

assist the controller in maintaining separation during

final approach.
[ 17 ]

• Simultaneous (independent) converging

instrument approaches. Improvements in

converging runway approaches must take

into account the wide variety of converging

runway configurations that are in use. This

program will investigate potential changes in

Terminal Instrument Procedures (TERPS)

and air traffic requirements in an effort to

improve efficiency of converging approach

procedures. As a preliminary step, a work

group has been formed to study the various

applications available for this new procedure.

Of the busiest 100 airports in the country,

38 may benefit from this improved procedure.

Much of the delay in the aviation system

could be reduced if the approach procedures

used during IMC were able to approximate the

operational capacity of those used during VMC.

The initiatives in instrument approach procedures we have described focus on the following

objectives:

• The use of closely spaced parallel runways

for simultaneous or near-simultaneous

arrivals.

• More efficient spacing along the final approach path.

• Increased arrival rates to converging and

intersecting runways.

• A reduction in the airspace needed to transition to and execute an approach.

NTZ

15° - 100°

45°

Triple approaches — dual parallels and one converging.

New approach procedures are thoroughly tested, often

including real-time simulations at the FAA’s Technical Center.
[ 18 ]

IMPACT ON SYSTEM CAPACITY

In 1992, about 65 percent of all significant

delays were attributed to weather. When

weather conditions reduce visibility to instrument flight rules (IFR) operations, separations

between aircraft must be increased, and arrival

rates and airport capacity decrease accordingly.

Instrument approach procedures are much more

restrictive than the visual procedures in effect

during better weather conditions.

DEVELOPMENTS IN AVIATION WEATHER

Over half of all delays are attributable to weather.

Improving our ability to forecast the weather

offers the potential for increasing system capacity more cost effectively than many other alternatives. Simply knowing when instrument

meteorological conditions (IMC) will start and

end would result in significant improvements in

capacity. Many of the delays due to weather

result from not being able to predict this information accurately. For example, because of

morning fog at Chicago O’Hare, air traffic

control (ATC) may have limited the arrival

acceptance rate to 50 percent of potential and

begun a ground hold that is expected to continue until 11:00 a.m., based on a forecast that

the fog will not lift until that time. If the fog

actually lifts at 10:00 a.m., the pipeline of

aircraft will not be filled quickly enough to

regain normal acceptance rates until at least

11:00 a.m., even if the ground hold is removed

immediately. Thus, inadequate weather information results in an unnecessary loss of 50

percent of capacity at Chicago O’Hare for the

hour between 10:00 a.m. and 11:00 a.m., and

this loss of capacity has a ripple effect throughout the national aviation system.

Improved weather information enhances

flight safety, improves flight planning and

efficiency, reduces ATC and pilot workload, and

increases system capacity. Improved flight

planning saves fuel and reduces costs.

Efforts are underway to enhance our understanding of and our ability to observe and

predict a wide range of aviation weather phenomena for both domestic and oceanic airspace.

• Aircraft icing, surface and aloft.

• En route and transition turbulence.

• Ceiling and visibility.

• Thunderstorms and microbursts.

• En route and terminal winds and

temperatures.

To better observe current weather and

generate more accurate short-term forecasts,

various models, algorithms, and meteorological

sensors are being developed. Surface-based and

airborne sensors, as well as weather radars, are

now being implemented to provide near-realtime three-dimensional weather data that is not

now available.
[ 19 ]

ACCOMPLISHMENTS

Winds and Temperatures Aloft

Knowledge of current and future winds and

temperatures aloft is critical to FAA traffic management functions and to airline flight planning

to determine optimum routing, time en route,

and fuel management. To improve the quality

and timeliness of this information, the FAA has

acquired access to automated reporting of nearreal-time observations of winds and temperatures aloft from aircraft equipped with the

ARINC Communication Addressing and Reporting System (ACARS). These observations are

then transmitted to the National Weather Service (NWS), which in turn produces a data base

and a series of products describing current and

future wind and temperature conditions aloft.

This program is called the Meteorological Data

Collection and Reporting System (MDCRS).

MDCRS is currently collecting 8,000 automated

reports per day. In FY94, the rate is expected to

increase to 16,000 reports per day. MDCRS has

already produced a 25 percent improvement in

the accuracy of forecasts of winds and temperatures aloft.

International Aviation Weather Codes

The Capacity Office led the interagency

effort (FAA, NWS, DOD, and DOS) to establish a

U.S. position on standards proposed by ICAO for

surface weather observations (METAR) and for

terminal weather forecasts (TAF). The Office

then led the effort within FAA to develop an

implementation plan. The first phase was completed on July 1, 1993, with the transmission of

METAR and TAF weather information from 250

and 80 airports respectively. Adopting a common international aviation weather code for

pilots and flight operations personnel worldwide

will reduce the cost of avionics by providing

weather information in common units and

formats, reduce training time, and reduce the

chances for any errors by misinterpreting

weather information due to code differences.

Providing aviation weather services to the

aviation industry is a joint effort of the FAA and

the NWS, with support from DOD. In response

to industry interest, a National Aviation Weather Program Plan (NAWPP) was completed and

published last November. The Capacity Office

led the interagency planning effort, under the

auspices of the Office of the Federal Coordinator for Meteorology. Other federal agencies participating in the study were NWS, DOD, NASA,

and National Transportation Safety Board

(NTSB). The focus of the NAWPP was on identifying the high-level needs of industry users for

aviation weather services and assigning priorities

for fulfilling those needs. This planning effort

employed extensive industry user involvement

and produced recommendations for action plans

in eight areas.

Initiative to Define Weather Requirements for

Safety, Capacity, and Operational Efficiency

We are now entering the second phase of

this comprehensive effort to define detailed

weather information needs for pilots, dispatchers, and air traffic controllers. This initiative is

taking advantage of extensive user participation

to help define the required access to weather

information and to address the best format for

disseminating the information, e.g., graphic

versus alphanumeric.

FAA/NWS Memorandum of Understanding

A Memorandum of Understanding between

the FAA and the NWS is in the final review

process within the FAA. This formal document

will spell out the overall division of responsibilities in providing weather service to air traffic

controllers and industry users. It will help to

reduce the confusion among users about which

agency is responsible for various aviation

weather services.

National Aviation Weather Program

Plan Published
[ 20 ]

AIRPORT TACTICAL INITIATIVES

The recommendations by Airport Capacity

Design Teams have emphasized constructing

new runways and taxiways, installing enhanced

facilities and equipment, and changing instrument approach procedures. These improvements

are normally processed through established,

long-term procedures. The Capacity Office has

recently initiated an effort to identify, evaluate,

and implement capacity improvements that are

achievable in the near term and will provide

more immediate relief for chronic delay-problem airports.

Airport Capacity Enhancement (ACE)

Action Teams, made up of representatives from

airport operators, air carriers, other airport

users, and aviation industry groups together

with FAA representatives, are now being established at selected airports to assess near-term,

tactical initiatives and guide them through

implementation.

The first of these ACE Action Teams has

been established at Los Angeles International

Airport. The team is evaluating the impact on

the crossfield taxiway system of proposed new

gates on the west side of the Tom Bradley

International Terminal immediately adjacent to

Los Angeles International Airport looking west toward the

Tom Bradley International Terminal.

PLANS FOR THE FUTURE

the taxiway system. The study will examine the

causes of delay associated with operations in the

terminal area and evaluate capacity benefits and

delay-cost savings of proposed improvements.

TERMINAL AIRSPACE STUDIES

When an Airport Capacity Design Team

study is completed, an airport has a recommended plan of action to increase its capacity.

But, this plan will do little good if the airspace

in the vicinity of the airport cannot handle the

increased traffic. For this reason, the Capacity

Office has been developing a program of Airspace Capacity Design Team studies of the

terminal and en route airspace associated with

delay-problem airports across the country. These

studies are intended to follow the Airport

Capacity Design Team studies. The first of these

Terminal Airspace Studies are currently being

planned for Philadelphia International Airport

and Seattle-Tacoma International Airport.

REGIONAL CAPACITY DESIGN TEAMS

Looking beyond the individual airport and

its immediate airspace, the Capacity Office is

planning a series of Regional Capacity Design

Team studies. These regional studies will analyze all of the major airports in a metropolitan

or regional system and model them in the same

terminal airspace environment. This regional

perspective will show how capacity-producing

improvements at one airport will affect air traffic

operations at the other airports and within the

terminal airspace. The first of these regional

studies is planned for the Los Angeles Basin

airports.
[ 21 ]

AIRSPACE DEVELOPMENT

The Airspace Capacity Design Program will

continue to undertake projects to study capacity

and delay problems and support planning efforts

related to air traffic operations. The goal is to

identify, test, and quantify capacity-enhancing

modifications to the national airspace structure

to ensure that airspace constraints are not a

limiting factor on the air transportation system.

IMPROVED INSTRUMENT APPROACH PROCEDURES

New air traffic control approach procedures

continue to be developed to take advantage of

improving technology, enhance system capacity,

and improve flight safety. The goal is to have

capacity during IMC equal capacity during VMC.

The Capacity Office will work closely with Air

Traffic, Flight Standards, Aviation Standards,

Research and Development, and the FAA Technical Center to ensure these new procedures are

thoroughly tested, to include real-time simulations and live demonstrations.

AVIATION WEATHER

The Capacity Office will continue as an

integral part of the FAA’s overall effort to improve aviation weather service. Work has begun

on developing the action plans recommended by

the National Aviation Weather Program Plan

(NAWPP), and work is continuing on implementation of international aviation weather codes

for surface observations (METAR) and terminal

forecasts (TAF).

As a part of this effort, the Capacity Office

will be hosting a National Aviation Weather

Users Forum, currently scheduled for November

30 through December 2, 1993, in the Washington, D.C. area. This public meeting, to which

aviation weather users and providers are invited,

is intended to get industry validation of detailed

user needs and priorities and to define responsibilities for aviation weather services in terms of

who provides, who pays, who sets standards,

and which services are regulated.

U.S. Weather Satellite Photo, 09/13/93, 0500 EDT.

U.S. Weather Satellite Photo, 09/13/93, 1300 EDT.

U.S. Weather Satellite Photo, 09/13/93, 1800 EDT.
[ 22 ]

CAPACITY INITIATIVES PAMPHLET

The second in a series of pamphlets on

Capacity Initiatives is being prepared now for

publication. The latest pamphlet will describe

capacity-producing improvements in air traffic

control procedures, increased utilization of

multiple runways, and new radar systems and

other technologies that have recently become

available or will be available in the next three to

five years. It should be published during the Fall

of 1993. The first pamphlet in the series, entitled Near-Term Capacity Initiatives, was published in July 1992 and reprinted in September

1992.

MISCELLANEOUS

AVIATION SYSTEM CAPACITY PLAN

The 1993 Aviation System Capacity Plan

should be published and available for distribution by the Fall of 1993. Copies of the plan will

be sent to the same distribution list as the

previous year’s plan. Please send any requests to

be included on the distribution list to the Office

of System Capacity and Requirements.

QUESTIONS, COMMENTS, REQUESTS

Any questions or comments concerning our

Annual Report or any of our efforts in the Capacity Office would be greatly appreciated.

These and any requests for publications should

be directed to:

Federal Aviation Administration

Office of System Capacity and Requirements

800 Independence Avenue, S.W.

Washington, D.C. 20591

(202) 267-7370
[ 23 ]

1 FAA Aviation Forecasts, Fiscal Years 1993–2004, FAA –

APO 93–1, February 1993. The economic scenario

used to develop the FAA Aviation Forecasts for the

period 1993 through 1998 was provided by the

Executive Office of the President, Office of Management and Budget (OMB). For the period from

1999 through 2004, the economic scenario used

consensus growth rates of the economic variables,

based on forecasts prepared by DRI/Mc Graw-Hill,

Evans Econometrics, and the WEFA Group.

2 Aircraft direct operating costs include fuel, crew,

aircraft maintenance, and the like, but not the costs

of passenger inconvenience or time lost. Actual

average aircraft operating costs depend on the mix of

aircraft types operating at each individual airport.

3 The average aircraft direct operating cost for the mix

of aircraft types operating at Charlotte/Douglas

International Airport was $1,400 per hour in 1989

dollars. This value was used to compute delay-cost

savings at all demand levels.

4 The average aircraft direct operating costs for the

mix of aircraft types operating at Detroit Metropolitan Wayne County Airport were $1,550 per hour at

409,000 aircraft operations per year and $1,649 per

hour at 500,000 operations per year (in 1989

dollars).

FOOTNOTES

5 The average aircraft direct operating cost for the mix

of aircraft types operating at Phoenix Sky Harbor

International Airport was $1,080 per hour in 1988

dollars. This value was used to compute delay-cost

savings at all demand levels.

6 The average aircraft direct operating cost for the mix

of aircraft types operating at Nashville International

Airport was $986 per hour in 1989 dollars. This

value was used to compute delay-cost savings at all

demand levels.

7 The average aircraft direct operating cost for the mix

of aircraft types operating at Orlando International

Airport was $1,657 per hour. This value was used to

compute delay-cost savings at all demand levels.

8 The city of Austin now plans to convert Bergstrom

Air Force Base, which will be transferred to the city

in 1993, into the new Austin airport and relocate all

commercial activity there in 1997–1998.

† Based on the average direct operating costs of $1,600

per hour. See page 5.