FLIGHT TRANSPORTATION LABORATORY
REPORT R94-5
DEPARMN
ANALYSIS OF AIRCRAFT SURFACE MOTION
AT BOSTON LOGAN INTERNATIONAL AIRPORT
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Robert Elias Alhanatis
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ANALYSIS OF AIRCRAFT SURFACE MOTION
AT
BOSTON LOGAN INTERNATIONAL AIRPORT
by
Robert Elias Alhanatis
B.S. Aerospace Engineering
Boston University, 1992
Submitted to the Department of Aeronautics and Astronautics
in Partial Fulfillment of the Requirements for the
Degree of
MASTER OF SCIENCE
at the
Massachusetts Institute of Technology
September 1994
© 1994 Robert Elias Alchanatis
All Rights Reserved
The author hereby grants to MIT permission to reproduce and to
distribute publicly paper and electronic copies of this thesis
document in whole or in part.
Signature of the Author.....................................................................................
Department of Aeronautics and Astronautics
July 13, 1994
Certified by..............................................................................................--.
Professor Robert W. Simpson
Director, Flight Transportation Laboratory
Thesis Supervisor
... .-A ccepted by..........................................................................................
Professor Harold Y. Wachman
Chairman, Department Graduate Committee
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ANALYSIS OF AIRCRAFT SURFACE MOTION
AT
BOSTON LOGAN INTERNATIONAL AIRPORT
by
ROBERT ELIAS ALHANATIS
Submitted to the Department of Aeronautics and Astronautics
in Partial Fulfillment of the Requirements for the Degree of Master of Science in
Aeronautics and Astronautics
ABSTRACT
The purpose of this thesis is to examine the nature of aircraft surface motion on
the airport surface during normal operations. Twelve hours of radar data, gathered by
MIT Lincoln Laboratories from Logan airport in Boston, were made available for this
study. Specifically, the data included target position reports from the ASDE-3 surface
surveillance radar and the ASR-9 radar from the near terminal airspace information. This
data covers a variety of runway configurations, weather conditions, traffic levels and high
or low visibility conditions.
The study is divided into three sections. The first one focuses on the runway, and
examines occupancy times, exit velocities, exit usage and velocity profiles of the final
approach and landing phase. The second section, analyzes fourteen runway-taxiway
intersections. Results are presented for the crossing times and usage of these
intersections. The analysis also focuses on relating crossing times and usage to crossing
direction, runway configuration and aircraft size. Finally, average taxiway velocities and
the overall taxiway usage is measured. Additionally, the role that the location of the
taxiway segment as well as its length, plays in the variation of these velocities are
examined. Where possible, this study includes means, standard deviations and sample
sizes of the variables in question.
Thesis Supervisor:
Dr. Robert W. Simpson
Director, Flight Transportation Laboratory
11IN1110111IM111w,
Acknowledgments
I would like to thank several people for their time and support throughout the process of
writing this thesis. First of all, I would like to extend my sincere gratitude to Professor
Robert Simpson, my thesis supervisor, for his constant support and guidance. I am truly
grateful for the opportunity to have worked with him.
I would also like to thank MIT Lincoln Labs for providing the data for this thesis
Jerry Welch, Ted Morin and Jim Eggert for assisting me in getting the
particular
in
and
data, answering my questions and providing me with many useful suggestions.
Additionally, I would like to thank John Pararas, Dennis Mathaisel and Husni Idris for
their help in developing the data processing software and the GMS interface.
I would also like to thank Professor Amadeo Odoni for his insightful remarks and
Professor Peter Belobaba for teaching the Airline Management and Airline Econimics
courses during my studies. I would also like to express my thanks to all my fellow
classmates. My stay at the Flight Transportation Lab has been a rewarding experience
thanks to them.
Finally, and most importantly, I would like to express my deepest gratitude to my parents
for their continues love and support.
R. A.
Cambridge, Massachusetts
July, 1994
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Table of Contents
A bstract....................................................................................................................
A cknow ledgm ents....................................................................................................
...... .... ..
Table of Contents................................................................................
List of Tables.......................................................................................................--.
..
List of Figures....................................................................................................
3
5
7
9
10
Chapter 1:
Introduction.....................................................................................
Background........................................................................
1.1
M otivation........................................................................
1.2
Scope..................................................................................
1.3
14
14
16
16
Chapter 2:
The M easurement Task.................................................................
18
2.1
2.2
2.3
2.4
Chapter 3:
D ata A nalysis................................................................................
3.1
3.2
3.3
3.4
3.5
3.6
Chapter 4:
Introduction........................................................................
The Runway and Taxiway System.....................................
D ata Collection.................................................................
Available D ata...................................................................
Introduction........................................................................
Preliminary D ata Processing.............................................
Data Irregularities..............................................................
Runway A nalysis .............................................................
3.4.1 Runway Occupancy Time During Landing...........
3.4.2 Exit U se.................................................................
3.4.3 Exit Velocities............................
3.4.4 Velocity Profiles....................................................
Landing Velocity Profiles..............
3.4.4.1
Final Approach Velocity Profiles.....
3.4.4.2
Intersection A nalysis ........................................................
3.5.1 Intersection Crossing Tim es...................................
3.5.2 Intersection U se........................................................
Taxiway A nalysis.................................................................
3.6.1 Taxiw ay A verage Velocity.......................................
3.6.2 Taxiw ay U se.............................................................
Conclusions......................................................................................
4.1
4.2
4.3
4.4
4.5
Introduction..........................................................................
Runways...............................................................................
Intersections..........................................................................
Taxiways..............................................................................
Directions for Future Research.............................................
References................................................................
. ...................
18
19
24
25
29
29
30
35
36
36
50
58
70
70
83
90
90
103
106
106
110
121
121
122
123
124
124
126
1111116111111111
ill,
List of Tables
Chapter 2
2.2
The Runway and Taxiway System
Table 2.2
Runway Configurations at Logan Airport.........................
2.4
Available Data
Runway Configuration for Data Block-1.............................
Table 2.4.1
Weather information for Data Block-I................................
Table 2.4.2
Table 2.4.3
Runway Configuration for Data Block-2.............................
Table 2.4.4
Weather information for Data Block-2................................
Runway Configuration for Data Block-3.............................
Table 2.4.5
Weather information for Data Block-3................................
Table 2.4.6
Runway Configuration for Data Block-4.............................
Table 2.4.7
Table 2.4.8
Weather information for Data Block-4................................
Table 2.4.9
Runway Configuration for Data Block-5.............................
Weather information for Data Block-5................................
Table 2.4.10
Table 2.4.11
Runway Configuration for Data Block-6.............................
Table 2.4.12
Weather information for Data Block-6................................
Runway Configuration for Data Block-7.............................
Table 2.4.13
Table 2.4.14
Weather information for Data Block-7................................
Runway Configuration for Data Block-8.............................
Table 2.4.15
Table 2.4.16
Weather information for Data Block-8................................
Table 2.4.17
Runway Configuration for Data Block-9.............................
Table 2.4.18
Weather information for Data Block-9................................
Runway Configuration for Data Block-10...........................
Table 2.4.19
Table 2.4.20
Weather information for Data Block-10..............................
21
Chapter 3
3.2
Prelimin ary Data Processing
Table 3.2.1
Typical Sample Information about a Target......................
Series of Nodes that Define the Airport Run. & Tax........
Table 3.2.2
3.4.1 Runway Occupancy Time During Landing
Table 3.4.1.1 :
Average Occupancy Time During Landing......................
Table 3.4.1.2 :
Exits Links Runways 27, 9...............................................
Table 3.4.1.3 :
Exits Links Runways 33L, 15 R.......................................
Table 3.4.1.4 :
Exits Links Runways 4L, 22R........................
Exits Links Runways 4R, 22L..........................................
Table 3.4.1.5 :
3.4.2 Exit Use
Classification of Aircraft....................................................
Table 3.4.2
3.5.1 Intersection Crossing Times
Series of Links that Corresponds to Each Intersection.........
Table 3.5.1
3.5.2 Intersection Use
Number of Aircraft Using Each Intersection......................
Table 3.5.2
30
32
36
37
37
40
40
50
92
103
List of Figures
Chapter 2
2.2
The Runway and Taxiway System
Figure 2.2.1
Boston Logan International Airport - Location Map......... 19
Figure 2.2.2 :
Runway and Taxiway Configuration - Logan Airport....... 20
Figure 2.2.3 :
Taxiway System Around the Terminal Area.................... 23
Chapter 3
3.2
Preliminary Data Processing
Figure 3.2.1 :
Logan Airport - GMS Format..............................................
Figure 3.2.2 :
N ode-Link Network.............................................................
3.4
Runway Analysis
3.4.1 Runway Occupancy Time During Landing
Figure 3.4.1.1 :
Runw ay 33L/15R.................................................................
Figure 3.4.1.2 :
Runw ay 27/9.........................................................................
Figure 3.4.1.3 :
Runways 4R/22L, 4L/22R and 15L/33R..............................
Figure 3.4.1.4 :
Aver. Occup. Time During Landing Run 4R Block 1........
Figure 3.4.1.5 :
Run 4R Block 6........
Figure 3.4.1.6 :
Run 4R Block 9........
Figure 3.4.1.7 :
Run 22L Block 8......
Figure 3.4.1.8 :
Run 22L Block 10....
Figure 3.4.1.9 :
Run 27 Block 2.........
Figure
Figure
Figure
Figure
Figure
Figure
Figure
3.4.1.10:
3.4.1.11:
3.4.1.12:
3.4.1.13:
3.4.1.14:
3.4.1.15:
3.4.1.16:
3.4.2 Exit Use
Figure 3.4.2.1 :
Exit Use per Aircraft Class
Figure 3.4.2.2 :
Exit Use per Aircraft Class
Figure 3.4.2.3 :
Exit Use All Classes
Figure 3.4.2.4 :
Exit Use All Classes
Figure 3.4.2.5 :
Exit Use per Aircraft Class
Figure 3.4.2.6 :
Exit Use per Aircraft Class
Figure 3.4.2.7 :
Exit Use All Classes
Figure 2.4.2.8 :
Exit Use All Classes
Figure 3.4.2.9 :
Exit Use per Aircraft Class
Figure 3.4.2. 10:
Exit Use per Aircraft Class
Figure 3.4.2.11:
Exit Use per Aircraft Class
Figure 3.4.2.12:
Exit Use per Aircraft Class
Figure 3.4.2.13:
Exit Use per Aircraft Class
Run 27 Block 3.........
Run 27 Block 8.........
Run 27 Block 10.......
Run 33L Block 2......
33
34
38
39
41
43
43
44
45
45
46
46
47
47
48
48
Run 33L Block 5......
Run 15R Block 4...... 49
Run 15R Block 7...... 49
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
4R Block 1........
4R Block 6........
4R Block 9........
22L Block 8......
22L Block 10....
27 Block 2.........
27 Block 3.........
27 Block 8.........
27 Block 10.......
33L Block 2......
33L Block 5......
15R Block 4......
15R Block 7......
51
51
52
53
53
54
54
55
55
56
56
57
57
Nlbhw
I
3.4.3 Exit Velocities
Run 4R Block 1........
Average Exit Vel All Classes
Run 4R Block 6........
Figure 3.4.3.2 :
Run 4R Block 9........
Figure 3.4.3.3 :
Run 22L Block 8......
Figure 3.4.3.4 :
Run 22L Block 10....
Figure 3.4.3.5 :
Run 27 Block 2.........
Figure 3.4.3.6 :
Run 27 Block 3.........
Figure 3.4.3.7 :
Run 27 Block 8.........
Figure 3.4.3.8 :
Run 27 Block 10.......
Figure 3.4.3.9 :
Run 33L Block 2......
Figure 3.4.3.10:
Run 33L Block 5......
Figure 3.4.3.11:
Run 15R Block 4......
Figure 3.4.3.12:
Run 15R Block 7......
Figure 3.4.3.13:
Average Exit Vel per Aircraft Class Run 4R Block 1........
Figure 3.4.3.14:
Run 4R Block 6........
Figure 3.4.3.15:
Run 22L Block 10....
Figure 3.4.3.16:
Run 27 Block 2.........
Figure 3.4.3.17:
Run 27 Block 10.......
Figure 3.4.3.18:
Run 33L Block 2......
Figure 3.4.3.19:
Run 33L Block 5......
Figure 3.4.3.20:
Run 15R Block 4......
Figure 3.4.3.21:
Run 15R Block 7......
Figure 3.4.3.22:
3.4.4 Velocity Profiles
Landing Velocity Profiles
3.4.4.1
Run 4R Block 1........
Landing Velocity Profiles
Figure 3.4.4.1.1:
Run 4R Block 6........
Figure 3.4.4.1.2:
Run 4R Block 9........
Figure 3.4.4.1.3:
Run 22L Block 8......
Figure 3.4.4.1.4:
Run 22L Block 10....
Figure 3.4.4.1.5:
Run 27 Block 2.........
3.4.4.1.6:
Figure
Run 27 Block 3.........
Figure 3.4.4.1.7:
Run 27 Block 8.........
Figure 3.4.4.1.8:
Run 27 Block 10.......
Figure 3.4.4.1.9:
Run 33L Block 2......
Figure 3.4.4.1.10:
Run 33L Block 5......
Figure 3.4.4.1.11:
Run 15R Block 4......
Figure 3.4.4.1.12:
Run 15R Block 7......
Figure 3.4.4.1.13:
Profiles
Velocity
Approach
Final
3.4.4.2
Run 4R Block 1........
Final Approach Velocity Profiles
Figure 3.4.4.2.1:
Run
4R Block 6........
Figure 3.4.4.2.2:
4R Block 9........
Run
Figure 3.4.4.2.3:
22L Block 8......
Run
Figure 3.4.4.2.4:
22L Block 10....
Run
Figure 3.4.4.2.5:
27 Block 2........
Run
3.4.4.2.6:
Figure
Run
27 Block 3.........
Figure 3.4.4.2.7:
27 Block 8.........
Run
Figure 3.4.4.2.8:
27 Block 10.......
Run
Figure 3.4.4.2.9:
Run
33L Block 2......
Figure 3.4.4.2.10:
33L Block 5......
Run
Figure 3.4.4.2.11:
15R Block 4......
Run
Figure 3.4.4.2.12:
Run 15R Block 7......
Figure 3.4.4.2.13:
Figure 3.4.3.1 :
3.5
Intersection Analysis
58
59
59
60
60
61
61
62
62
63
63
64
64
65
66
66
67
67
68
68
69
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
84
85
85
86
86
87
87
88
88
89
89
3.5.1 Intersection Crossing Times
Figure 3.5.1.1 :
Typical Intersection..............................................................
Figure 3.5.1.2 :
Logan's Intersections...........................................................
Figure 3.5.1.3 :
Average Intersection Crossing Times
Block 1.........
Figure. 3.5.1.4 :
Block 2.........
Figure 3.5.1.5 :
Block 3.
Figure 3.5.1.6 :
Block 4.
Figure. 3.5.1.7 :
Block 5.
Figure 3.5.1.8 :
Block 6.
Figure 3.5.1.9 :
Block 7.
Figure 3.5.1.10:
Block 8.........
Figure: 3.5.1.11:
Block 9.........
Figure: 3.5.1.12:
Block 10.......
Figure 3.5.1.13: Avg. Inters. Cros. T.In Dir
Int. 10, 11, 12, 13, 14......
Figure 3.5.1.14: Avg. Inters. Cros. T. Out Dir
Int. 10, 11, 12, 13, 14......
Figure 3.5.1.15: Avg. Inters. Cros. T. Int Dir
Int. 6................................
Figure 3.5.1.16: Avg. Inters. Cros. T. Out Dir
Int. 6................................
Figure 3.5.1.17:
Figurei 3.5.1.18:
Figure 3.5.1.19:
Figure 3.5.1.20:
3.5.2
Figure
Figure
Figure
Figure
3.6
Avg. Int..
Avg. Int..
Avg. Int..
Avg. Int..
Cros. T. per Aircraft Class
Cros. T. per Aircraft Class
Cros. T. per Aircraft Class
Cros. T. per Aircraft Class
Intersection Use
Number of Aircraft Using Each Intersection
3.5.2.1 :
Configuration :
Arr : 4R, 4L
3.5.2.2 :
Configuration :
Arr: 33L
3.5.2.3 :
Configuration :
Arr: 27, 22L
3.5.2.4 :
Configuration :
Arr: 15R
Taxiway Analysis
3.6.1
Block 1....................
Block 2....................
Block 4....................
Block 5....................
Dep
Dep
Dep
Dep
94
94
95
95
96
96
97
97
98
98
99
99
100
100
101
101
102
102
: 9, 4L................ 104
: 33L, 22R......... 104
: 22R, 22L......... 105
: 9, 15R.............. 105
Taxiway Average Velocity
Figure 3.6.1.1 :
Average Velocity in Taxiways.............................................
Figure 3.6.1.2 :
Average Velocity in Taxiways
Various Lengths.......
Figure 3.6.1.3 :
Average Velocity in Taxiways
Various Locations.....
Figure 3.6.1.4 :
Average Velocity in Taxiways
Various Loc.&Leng..
3.6.2 Taxiway Use
Figure 3.6.2.1 :
Taxiway use Inner and Outer Taxilane
Block 1.........
Figure 3.6.2.2 :
Block 2.........
Figure 3.6.2.3 :
Block 3.........
Figure 3.6.2.4 :
Block 4.........
Figure 3.6.2.5 :
Block 5.........
Figure 3.6.2.6 :
Block 6.........
Figure 3.6.2.7 :
Block 7.........
Figure 3.6.2.8 :
Block 8.........
Figure 3.6.2.9 :
Block 9.........
Figure 3.6.2.10:
Block 10.......
Figure 3.6.2.11:
Taxiway use Supporting Taxiways
Block 1.........
Figure 3.6.2.12:
Block 2.........
Figure 3.6.2.13:
Block 3.........
Figure 3.6.2.14:
Block 4.........
Figure 3.6.2.15:
Block 5.........
Figure 3.6.2.16:
Figure 3.6.2.17:
Figure 3.6.2.18:
Figure 3.6.2.19:
Figure 3.6.2.20:
90
91
Block 6.........
Block 7.........
Block 8.........
Block 9.........
Block 10.......
107
108
109
109
111
111
112
112
113
113
114
114
115
115
116
116
117
117
118
118
119
119
120
120
iih
Chapter 1
Introduction
1.1
Background
After forty years of regulation by the Civil Aeronautics Board, in 1978 Congress enacted
the Airline Deregulation Act, which phased out economic regulation of the industry. In
the years following deregulation many new carriers entered the airline industry. The old
and the new airlines soon started servicing new city-pair markets, offering expanded
services and competitive fares. These developments resulted in a significant increase in
the overall traffic levels. In order to provide higher schedule frequencies and more
efficient use of their fleet, the airlines soon abandoned the point-to-point route networks
and adopted hub and spoke network systems that concentrated traffic around hub airports.
U11111fil.,
,
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il1116
1
The increased passenger traffic coupled with the concentration of this traffic around, led
to congestion within the available airspace and subsequent delays in these hub airports.
Due to the aforementioned reasons, the need to develop means for greater
efficiencies in aircraft operations became apparent. Major efforts are undertaken today,
focusing on the use of advanced technologies for airborne and ground traffic control
systems in a concentrated effort to decrease the unused airspace and increase airport
capacity while simultaneously maintaining or even increasing safety levels. One such
area of focus is the airport surface, where especially in periods of low visibility, aircraft
experience significant delays on their way to the gate or departing runway. During the
last decade, various systems have been conceptualized and are currently under
development which deal with problems controllers and pilots face every day on the
airport surface.
The major objective of these surface traffic systems is to enhance the safety,
capacity, and productivity of these airports, while at the same time reducing delays and
the workload of both controller and pilot. This is accomplished via the development of
advanced communications, surveillance and automation techniques for use in the control
towers of major airports. Various subsystems address isolated problems such as runway
incursions, taxiway guidance and surface traffic surveillance.
Airport safety is intrinsically linked to capacity. The spacing between aircraft
necessarily reduces with increasing capacity, and safety suffers unless the reduction in
spacing is done carefully. The suggested long term solution is a surface traffic
management system that will address all these subsets of problems in an integrated
manner and safely control the airport surface area. Such a system must address the
capacity issues of ground congestion and effective departure sequencing through the
implementation of efficient routing and sequencing of aircraft on the surface, thereby the
system would decrease delays and increase airport safety. In order for such a system to be
successfully developed and implemented, information about the nature of aircraft motion
on the airport surface must be detailed.
1.2
Motivation
Few studies have been conducted to date on aircraft motion on the airport surface during
normal operations. In 1960 the Airborne Instruments Laboratory at Cornell University
published a series of reports about velocities and accelerations of aircraft at Kennedy
Airport in New York. Later, in 1972 the Flight Transportation Laboratory at MIT studied
the air-side activity of Boston Logan and Atlanta airports. Measurements were taken for
runway occupancy times, velocity profiles along the runways, taxiway speeds and
intersection delays. Unfortunately, most of the aircraft that operated during those years
are not in service today. Additionally, the data was gathered solely in periods of good
visibility and therefore the data of these reports is of little value today. It is therefore of
vital interest to measure the surface movements of today's aircraft as completely and
effectively as possible.
1.3
Scope
An aircraft engages in a series of non-uniform and complex maneuvers on its way
to the gate or the departing runway. A departing aircraft for example, after getting the
clearance to push back from the gate, has to follow a taxi route that will lead it to the
takeoff runway. This path varies depending on the layout of the taxiway system, the
Owwo
current runway configuration, and the location of the gate. It might be short or long and
might involve a considerable number of turns, stops, taxiway and runway crossings, and
varying length segments of straight taxing. Along this route, the pilot must be constantly
be aware of the position, not only of his own aircraft, but also of nearby aircraft, ground
vehicles (or even terminal buildings) in order to taxi safely and avoid any collisions. The
ability of the pilot to successfully taxi along the path depends on various factors. These
include the type (size) of aircraft that the pilot operates, the amount of traffic at that
particular instant at the airport, the surface visibility, the weather and surface conditions,
and the familiarity that the pilot might have with the specific taxiway system. We must
remember also, that the pilot during his taxi, is usually assisted by the ground controller
who directs him along his taxi route and provides him with information about
surrounding obstacles. It is important to note though, that the pilot is the one who makes
the final decisions and may override the controllers directions. For example, a controller's
request for a landing aircraft to use the first available exit can be ignored, or the pilot may
insist on taxiing to the starting end of a runway rather than start from an intermediate
point.
Such factors as the human element cannot easily be quantified and often introduce
variance into the events that we want to measure, and therefore must be taken in to
account in the final analysis. Among many surface motion variables that can be
measured, those of interest are: the approach speed of a landing aircraft, its landing speed
profile during roll-out, the runway occupancy time, the exit used, the exit velocity, the
time required to cross runway intersections, and the taxiing velocities on different
segments of the taxiway system. The analysis of these variables in conjunction with the
major factors that affect them will be the focus of this thesis.
----N-1---'---------
-
Chapter 2
The Measurement Task
2.1
Introduction
The first section of this chapter describes the existing runway and taxiway system
at Logan airport in Boston so the reader can get a better understanding of the airport
layout and better relate the measured variables. The second section, discusses the main
elements of the data collection method that was employed. Finally, the last section
provides information about the different days that the data was collected. Included in this
information, is a description of the weather and surface conditions as well as any
particular events that occurred during the collection period and which might be of interest
in the later stages of the analysis.
2.2
The Runway and Taxiway System
Boston Logan International Airport lies at the edge of Boston harbor, surrounded
by water in the majority of its perimeter. The commercial and residential area of East
Boston is adjacent to it while the Winthrop area lies across the harbor (Figure 2.2.1).
Figure 2.2.1
Logan is the dominant airport ( 70 % of the passenger traffic
1)
in a regional airport
system that also includes airports serving Hartford, Manchester, Worcester, Hyannis,
Portland, and Providence. It has five runways with four of them (4L, 4R, 33R and 27)
1 Boston Logan International Airport Capacity Enhancement Plan, October 1992 published by the FAA.
capable of handling large transport aircraft. Three of these runways (4R, 33R and 27)
have instrument landing capability. The configuration of the runways is rather complex
(Figure 2.2.2), as they intersect six times with each other.
Figure 2.2.2
Typically, peak hour demand is 100 operations per hour. The serving capability
depends on the runway operating configuration, and can vary from 46 operations per hour
during the most restrictive IFR conditions to 120 operations per hour during good VFR
weather 2 . This fluctuation is primarily due to the lack of parallel runways within
adequate spacing between them for simultaneous IFR approaches under certain weather
conditions. Consequently, at certain times all landings must be sequenced into a single
arrival stream, thus lowering the airport serving capability. The high proportion of
commuter aircraft operations at Logan further deteriorates the airport effective capacity,
as larger separations maybe needed under certain runway configurations to safely
accommodate these smaller sized aircraft due to the wake turbulence considerations
during mixed (in terms of size) operations. In addition, in order to keep the noise levels
that the nearby communities experience within reasonable levels, the Massachusetts Port
Authority has imposed certain regulations that further complicate aircraft operations.
Specifically, only certain runway configurations can be used at night and airlines are
required to conduct a specific portion of their Logan operations in Stage 3 equipment 3 .
The configurations 4 that are used most often at Logan are:
Table
2.2
IFR
VFR
Configuration
Arrivals
Departures
Arrivals
Departures
1
4L & 4R
4L, 4R & 9
4R
4L, 4R & 9
2
22L & 27*
22R & 22L
22L
22R & 22L
3
33L & 33R
27 & 33L
33L
33L
15R & 9
9, 15R & 15L*
4
These configurations employ hold-short procedures.
15R
15R & 9
2,4 Boston Logan International Airport Capacity Enhancement Plan, October 1992 published by the FAA.
3
Summary of Logan's Noise Abatement Rules and Regulations published by Massport.
Due to the complexity of the runway system, various procedures for intersection
departures and hold-short arrival are often used.
The taxiway system (Figure 2.2.3) consists of two main circumferential taxi lanes
(inner & outer) around the perimeter of the terminal building area with smaller taxiway
segments supporting the traffic towards the gate area. Longer taxiways also exist to feed
the outbound traffic to the departure runways, and the incoming traffic to the terminal
area. Runways 4R, 33L/15R and 27 have additional high speed exits conveniently located
so that the landing aircraft can vacate the runway as soon as possible, and then there are
various common taxi paths from these exits to the gate areas. For example, the high speed
exit most commonly used for runway 4R is exit 12 (link A29-A56) , and crosses runway
4L (used only for turboprop landings and takeoffs in this case) before joining taxiway N
(link A74-A75) to return to the terminal area.
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2.3
Data Collection
In the past, the techniques used to study the aircraft motion on the surface of
airports fell into two major categories : those that involved direct observation of the
traffic through a number of observers out in the airfield (the MIT study) and those
involving indirect observation through the use of radar or other types of monitoring
equipment.
Each one of the two methods has its own advantages and disadvantages. The
indirect radar method is more complex and requires expensive equipment but is fairly
accurate, imposes no interference in the traffic, and once operational can be employed for
long time periods. On the other hand, the other method (direct observation) is less
complex but requires a large number of observers, often in coordination with each other,
which involves intense manual effort and as one might suspect, and provides changing
levels of accuracy. Nevertheless, both methods require the authorization and cooperation
of the local FAA and airport authorities.
Luckily, in our case the MIT Lincoln Laboratories had installed an experimental
ground surveillance system that gathered data from Logan airport in Boston. Specifically,
the data included target position reports from the ASDE-3 surface surveillance radar and
the ASR-9 radar from the near terminal airspace traffic information. These two outputs of
the surveillance sensors were integrated by a combined tracking system that also provided
derived information about the velocity, heading and acceleration of the targets1 . A
simultaneous interface with the ARTS computer was often used and then information
about the aircraft type and flight number was made available.
2.4
Available Data
As mentioned earlier, Lincoln Laboratory had installed a surface traffic data
gathering system at Logan airport in Boston in 1993 for the development and testing of a
runway status lights network (ASTA-1) to help prevent runway incursions. As much as
ninety hours of traffic data were collected for this purpose. Approximately twelve of
these ninety hours were preprocessed by Lincoln Labs, and made available to this study
for further processing and analysis of the aircraft surface movements. These twelve hours
came in the form of 10 separate blocks of data, each corresponding to an individual data
gathering session. These blocks cover a variety of runway configurations, weather
conditions, traffic levels, and high or low visibility conditions. A brief description of the
available blocks of data follows:
Block-1
Day: Thursday, April 1, 1993
Time: 16:00-17:15 Local
Table 2.4.1
Runway Configuration
Departures Switched to Arrivals
Arrivals
4R
9, 4L
4R
Table 2.4.2
Wpthpr / ATIS
Temp Ceiling
Departures
4R
Visibility Wind
2 miles
n/a
500ft ovc
n/a
1800ft ovc 2 miles
n/a
11 00ft ovc
2 miles
Comments
50*@ 15knots Rain & Fog
Rain & Fog
-->
Thunderstorms
40*@ 20knots Rain & Fog
-->
Thunderstorms
40'@24knots
Block-2
Day: Friday, March 26, 1993
Time: 10:35-11:35 Local
Runway Configuration
Table 2.4.3
Arrivals
Departures
4
9
Switched to Arrivals
33L, 27
Weather / ATIS
Departures
33L, 22R
Table 2.4.4
Tern
Ceiling
Visibility Wind
55 * F
800ft. scat 7 miles
Comments
160*@7knots
Heavy Traffic, All Taxiways OK.
Block-3
Day:
Wednesday, April 21, 1993
Time: 17:35-18:35 Local
Runway Configuration
Table 2.4.5
Arri
Weather / ATIS
Table 2.4.6
|Temp
65 * F
Ceiling
Visibility Wind
2500ft ovc
15miles
Commients
180*@ l7knots Heavy Traffic.
Block-4
Day: Tuesday, March 26, 1993
Time: 13:15-14:15 Local
Run wvay Configuration
Table 2.4.7
IArrivals
115R
Wea. ther / ATIS
em
50
*F
IDepartures
19I
Table 2.4.8
Ceiling
Visibility
Wind
Sunny
12 miles
140*@7knots I Busy Traffic, later quieting down -M
Comments
Ph
IINNIIIIIIIII
Block-5
Day: Thursday, March 11, 1993
Time: 14:50-16:10 Local
Runway Configuration
Table 2.4.9
Arrivals
33L
Departures
122R, 33L
Table 2.4.10
Weather / ATIS
Comments
Temp Ceiling
Visibility
Wind
40 * F 5500ft
15 miles
300'@ l5knots Snow in the morning
Block-6
Day: Wednesday, March 31, 1993
Time: 19:15-20:15 Local
Table 2.4.11
Runway Configuration
IArrivals
DeNpartures
4R, 4L
9,4L
Table 2.4.12
Weather / ATIS
Temp Ceiling
Visibility Wind
420 F 6500ft
15 miles
Block-7
Day: Saturday, March 13, 1993
Time: 09:45-10:45 Local
Runway Configuration
Comments
110'@ 8knots
Snow in the morning
Table 2.4.13
De artures
vals
9,15R
Wather / ATTS
Comments
Temp Ceiling
Visibility Wind
31 *F 5000 ft
5 miles
127' @ 8knots ILS approaches 15R
33 *F 3800 ft
12 miles
110@ l7knots ILS approaches 15R, light snow
32* F 1500ftovc
1 mile
110*@ l5knots ILS approaches 4R, light snow
Day:
Wednesday, April 21, 1993
Time: 19:50-20:50 Local
Runway Configuration
Table 2.4.15
Arrivals
22L, 27
Weather / ATIS
Tern
Ceiling
Departures
22R, 22L
Table 2.4.16
Visibilit
59 * F 2500ft scat 15 miles
Wind
Comments
225 *@11knots n/a
Block-9
Day:
Tuesday, March 30, 1993
Time: 07:45-08:45 Local
Runway Configuration.
Table 2.4.17
Arrivals
4
Weather / ATIS
Tern
Ceiling
143 * F 1700 ft
Departures
9
Table 2.4.18
Visibilit
|2 miles
Wind
Comments
|40'@ l2knots Light drizzle & Fog
Block-10
Day:
Wednesday, April 21, 1993
Time: 09:00-10:02 Local
Runway Configuration
Table 2.4.19
Arrivals
ep rtures
22L, 27
Weather / ATIS
Tern
Ceiling
60 * F 2500ftovc
22R, 27
Table 2.4.20
Visibility Wind
15 miles
Comments
225@ l6knots n/a
Chapter 3
Data Analysis
3.1
Introduction
The first section of this chapter describes the preliminary data processing that was
undertaken along with various problems that were encountered due to several data
irregularities. The second section, provides a detailed runway analysis that includes
information about occupancy times, exit velocities, exit use, and landing velocities
profiles. The next section analyzes the intersection crossing times and the particular level
of use of each intersection. Finally, an analysis of the taxiway system is presented.
3.2
Preliminary Data Processing
As soon as the ten blocks of collected data were received, all the possible ways to
process and analyze the available information were considered. Each block of data
consisted of information about all the targets that were picked up by the ASDE-3 and
ASR-9 radar during each gathering session. Every target had its own ASDE and target ID
and contained among other things, position information in terms of x and y coordinates
with respect to the radar location, its derived velocity, acceleration, and heading, and the
corresponding time stamp for specific data items, measured in seconds from 0:00 GMT.
In addition, some targets included information about the aircraft type and airline flight
number (Table 3.2.1).
Tt:11584
Length: 287
Start time: 5795.3 1Endtime: 58588.6
States: DEP TAX STP
-deg-
Target ASDE
ID
ID
11584
11584
11584
11584
11584
11584
11584
11584
11584
5575
5575
5575
5575
5575
5575
5575
5575
5575
Time
Stamp State ASF
Position
(knots)
's
Heading Speed Accel.
ID
57995.375
57997.126
57998.878
58000.629
58002.382
58004.134
58005.885
58007.637
58009.388
1
2
3
4
5
6
7
8
9
TAX
TAX
TAX
TAX
TAX
TAX
TAX
TAX
TAX
3 North: -827.07
3 North: -827.22
g9 3 North: -802.69
3 North: -793.17
g76 North: -783.10
g76 North: -769.83
g76 North: -756.49
g76 North: -742.40
g76 North: -732.36
Flight Type
Num
East: 242.13
East: 249.34
East: 252.97
East: 256.41
East: 258.79
East: 263.59
East: 267.36
East: 271.39
East: 276.04
10.7
31.3
14.8
14.9
12.3
17.1
16.9
16.4
22
13.9
10.1
17.9
15.1
12.5
14
15.2
16.4
13.9
0.0874
-0.0552
0.113
0.0166
-0.042
0.0116
0.0215
0.0215
-0.0348
SR188
SR188
SR188
SR188
SR188
SR188
SR188
SR188
SR188
B747
B747
B747
B747
B747
B747
B747
B747
B747
Table 3.2.1: Typical sample information about a target inside a block of data.
The individual position reports for every target, constituted a very large amount of
information, and in order to be useful, had to be related again to the surface layout of the
airport. A graphical replay of the information of the available data was needed since it
would enable us to visualize the actual aircraft motion, check the analysis output, and
explain any possible counterintuitive findings.
MONOW1111110111WINA
Nild
HIM
NOWN1111m,
Recently, the Flight Transportation Laboratory at MIT had designed and
developed an aircraft Ground Motion Simulator (GMS) to realistically simulate airport
ground activity. The GMS simulates the environment at any arbitrary airport and provides
high quality graphic views, in color on UNIX workstations. This system has an internal
aircraft position generator that provides the simulation with motion updates. It was
decided to use the GMS system for visualization purposes, after bypassing its position
generator function and writing the necessary code to provide it with the actual aircraft
motion information from the Lincoln Laboratory data.
As a second step, the Logan airport geometrical layout along with its features
(terminal buildings, hangars, etc.) had to be inputted in the GMS system (Figure 3.2.1).
Next, the underlying network of nodes and links had to be inserted in GMS format data
files in order to define the runways and taxiways of the airport (Figure 3.2.2). Table 3.2.2
lists the series of nodes that define every taxiway. The next step was to write the
computer code that will associate every aircraft position with an airport link in order to be
able to automate the data reduction process. Various computer subroutines were also
written to perform other preliminary analyses of the recorded data. As a result, computed
values were obtained for approach speeds, exit velocities, intersections crossing times,
and various taxiway velocities. A more complete discussion of these values, and their
significance will start in the next chapter. During the analysis process various routines
had to be modified in order to overcome some irregularities in the collected data.
Taxiway
JIB08 A92
AV A93
B09
IA00IMA2
A42
A35
Series
A36I
of
Nodes
Y
INNER
OUTER
z
N2
1
02
D
NA
B
2A
01
K
L
N
A
B
00
s
101
T
A55
A97
B07
A97
A56
A98
B08
A79
A29
A80
B09
A81
A99
A95
B10
BOO
A96
A82
B01
B02
B03
B04
B05
B06
A83
A84
A85
A86
A70
A60
AOO
A10
A20
A50
A91
A92
A93
A94
A95
A96
A80
A71
A20
A37
B04
A33
A18
A73
B06
A63
A32
B03
'A21
B14
A49
A48
A98
A79
BOO
A02
A44
A04
B02
A66
A99
B05
B06
B02
B10
A72
A40
B14
A60
A32
A19
A59
A10
A64
A26
A70
A18
B13
A48
A14
A81
A77
A83
A03
A45
A05
A86
A65
A82
AOO
A50
A86
B11
N2
A38
A46
A31
A01
A39
A37
A31
A25
A24
A18
A17
A16
A12
A02
A04
A07
A90
A06
A43
A44
A09
A08
A47
A48
A23
A22
A75
A74
A73
A71
A69
A66
A63
A62
A51
A52
A43
A35
B13
A34
A33
A27
A85
A53
A78
[
Runy[~~
4R
4L
15R
22L
A61
A62
A64
A65
A57
A29
A14
A45
A09
A28
A27
A26
A25
A87
4R
22R
A68
A67
A72
A59
A54
A53
A42
A88
NI
A39
4L
33L
All
A12
A13
A01
A21
A22
A78
A77
A76
15R
33R
A58
A57
A55
A54
A74
A89
15L
27
A15
A06
A05
A03
A13
A17
A08
A38
B14
Ni
N2
9
_B11
15L
Table 3.2.2
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A49
A24
A51
A47
A46
A43
A14
A52
A53
A75
A28
A36
A34
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3.3
Data Irregularities
Due to the performance of the radar tracking system on the surface of the airport,
frequently during the gathering session, an aircraft target was dropped and then picked up
later on by the radar. The result was that in the data file, two different targets with
separate IDs (identification numbers) could in fact have been the same aircraft, and the
intermediate information about the aircraft movement between the time that the aircraft
was dropped from the radar and then picked up again was not available. Another
irregularity was the fact that not all targets had information about the aircraft type or
flight number. This limited the classification of results according to aircraft size to only
those targets where that information was available. In addition, this prevented us from
identifying targets that were not aircraft but rather other ground vehicles moving on the
airport surface and therefore might have infected our results if they were on the runways
or taxiways. Indeed, Blocks 3, 8 and 9 did not include any information about aircraft
types and flight number because the required computer tap was not in service during the
collection period.
3.4 Runway Analysis
3.4.1 Runway Occupancy Time During Landing
Runway occupancy time is the time over which a runway is effectively blocked
(occupied) to any other traffic by a single landing or departing aircraft. As such, it
potentially affects the traffic capacity of that runway. In the case when the runway is used
only for landings, the runway occupancy time and its potential variations currently do not
significantly affect the overall runway capacity as the inter-arrival radar separation
standards of the approaching aircraft cause spacing which is almost always greater than
the occupancy time. On the other hand, if the runway is used for mixed arrivals and
departures, the landing occupancy time becomes more critical. In that case, the shorter the
landing occupancy time, the more the time allowed to insert a takeoff between landings.
This results in higher runway operational capacity, and smaller delays for the departing
aircraft.
Average Occupancy Time During Landing
Runwa
4R
4L
22R
22L
27
9
33R_
33L
15R
15L
Data Block
1,6,9
n/a
n/a
8,10
2,3,8,10
n/a
n/a
2,5
4,7
n/a
igure
1,2,3
n/a
n/a
4,5
6,7,8,9
n/a
n/a
10,11
12,13
n/a
Table 3.4.1.1
The following tables (3.4.1.2 to 5) correlate each exit link of every runway from
the GMS airport layout (Figure 3.4.1.1 to 3) to an exit number for the graphs that follow.
Link
Exit Number
Runwa 27
Runwa
1
2
3
9
12
11
10
A06-A90
A05-A04
A03-A02
4
A13-AO1
5
6
7
A17-A18
A08-A09
A02-A28
A36-A15
7
6
5
A -B13
94
10
11
12
3
1
B14-A37
N1-A39
N2-A40
Table 3.4.1.2
Link
Exit Number
Runwal 33L Runway 15R
1
2
4
5
6
14
13
A12-A16
A13-A17
1
A01-A19
11
10
A21-A18
A22-A23
7I
8
7
96
10
11
12
5
4
1
14
2
1
Table 3.4.1.3
A14-A23
A14-A48
A52-A51
A53-A51
A53-A85
A75-A8
B11-B10
A78-A81
A77-A79
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Exit Number
I
Runwa 4LRunway22RI
1
14
2
13
3
12
Link
A39-N2
N1-N2
A42-A20
4
11
A43-A1O
5
6
10
9
A43-AOO
A46-A60
7
8
A47-A70
8
9
7
6
A51-A86
A53-A75
10
5
A53-A85
11
4
A54-A74
12
3
A59-A73
13
2
A72-A71
14
1
A67-69
Table 3.4.1.4
Exit Number
Runway 4R I Runway 22L
I
2___
_
3
4_ _
5LJ
13
14
16
A26-A32
14
A27-A33
13
ZA3
ZI941
11
8F
12
15
2
6
10
11
A12-A16
_____16_7_7
4-
9
97
A49-A48
=7
6
iF
4
14A48
A14-A52
_2
4I-
JL5-A6
3
=
E
Table 3.4.1.5
A57-A55
A62-A63
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The occupancy time during landing is measured from the moment the aircraft is
over the runway threshold until the time it has turned in the exit and its tail has crossed
the runway edge. Since our aircraft motion data was in the form of a series of discrete
radar hits (approximately every 1.7 sec on the surface), the time between the first hit
inside the first runway link and the first hit inside the exit link was used. In this way the
size of the error was minimized. As expected before the analysis of the results, occupancy
time tends to increase with the distance of the exit location from the runway threshold.
This is normally true except in some cases ( Figure 3.4.1.4 Exit 12 in Runway 4R and
Figure 3.4.1.7 Exit 11 in Runway 22L) where the particular angle of these exits allow
aircraft to exit with higher speeds, and therefore maintain a higher average landing
velocity resulting in occupancy times similar to exits that are located much closer to the
threshold.
Figures 3.4.1.4 through 3.4.1.16 are graphs of the average occupancy time during
landing for all aircraft types over a single runway and exit for every block of collected
data. It seems there exits a relationship between aircraft weight and occupancy time. We
observe that usually, the standard deviation of the occupancy times are quite small (5-10
seconds) for aircraft using the first exits, unlike for those using exits that are located
further down the runway. Runway 27 under configuration 2 (arrivals 27 and departures
22R) displayed the lowest occupancy time (35 seconds) for aircraft exiting at high speed
from exit 6 (Figures 3.4.1.9, 10, 12). In data block 8 (Figure 3.4.1.11), with similar weather
conditions but at night (20:00-21:00), most aircraft used exit number 8 (low speed) and
the occupancy times were significantly larger (53 seconds). The heavier aircraft tend to
land with higher velocities and require longer landing distances and therefore exit further
down the runway resulting in higher occupancy times. However aircraft using a given
exit have similar occupancy times, independent of aircraft size.
Average Occupancy Time During Landing
Block I
Runway 4R
Avg.Oc.Tim.
Stdev.
Landing Direction
m
q*
\O
knt
t-
W
ON~ 0-
C4
vE
M
kn\
Exit
Figure 3.4.1.4
Average Occupancy Time During Landing
Runway 4R
Block 6
80 -
Avg.Oc.Tim.
-
20
70 -
Stdev.
-
18
N
-
14
-
12
- 16
60 .
50
40
30
U
-I
+
+
-10
-6
Landing Direction
20 1
-4
-2
-
eI-
I
IO
U- I0 -
N-I
I
V-
Exit
Figure
1'. 3.4.1.5
U4t 4
1-
14
.1.
.4
*
-
-
4I~
I-
Average Occupancy Time During Landing
Runway 4R
Block 9
Avg. Oc. Tim.
80 -
Stdev.
-
20
-
18
-
16
- 14
50-
-
12
40 -
-
10
30 -
-8
10
-6
Landing Direction
20-
0
-
.1e~i .nr~
.t ~t
. 'I~
-
.0~O
:'
r.ON.
a U~Iu
oc
:/:
o~
Exit
Figure 3.4.1.6
44
-
~
p.e~i
I~ ~
r~
.
. -
mr~
~
.
.4
-2
~
~.C -0
. -
Average Occupancy Time During Landing
Block 8
Runway 22L
A.O.T.
- 20
- 18
Stdev.
- 16
--1 14
N
-------
-
U
12
I
-
10
-8
6
Landing
Direction
2
%O-
i
-1
e
______-
If
I
1.0
trn
~
e
en
i
-
Exit
Figure 3.4.1.7
Average Occupancy Time During Landing
Runway 22L
Block 10
I IIIIIIIIIIII
A .O .T
-20
Stdev.
- 18
-
16
U
-
14
N
- 12
U
Landing Direction
AU
- 10
-8
-6
-4
-2
0
-
I-
I-
-
I
-
I
0
I
Exit
Figure 3.4.1.8
Average Occupancy Time During Landing
Block 2
80 -
Runway 27
Avg.Oc.Tim.
- 20
-18
Stdev.
- 16
70 -
60-
- 14
--
50 -
-
12
40 -
- 10
30 -
-8
Landing Direction
20 10 0-
; -
0.
-
1
2
3
4
5
I;-- I; -- ;I -- I; -- I; -=
6
7
8
9 10 11
;
-
-6
-4
-2
*0
12
Exit
Figure 3.4.1.9
Average Occupancy Time During Landing
Block 3
80 -
Runway 27
-20
.18
Avg.Oc.Tim.
70 -
- 16
14
Stdev.
6050 -
--
N
-12
40 30
-
30 20 -
-10
-8
8
Landing Direction
-6
-p
10 r 1
2
3
- I - I
4
5
6
I 7
IN. i mi = a
8
Exit
Figure 3.4.1.10
9
10
11
12
Average Occupancy Time During LaRng
Runway 27
Block 8
80
Avg.Oc.Tim.
70
Stdev.
18
16-
N
14
50
12 *
40
10
8
6
30
Landing Direction
20
2
0
*0
1
2
3
4
5
6
7
8
9
10
11
12
Exit
Figure 3.4.1.11
Average Occupancy Time Durin Landin
Runway 27
Block 10
S
80
-
70
-
Avg.Oc.Tim.
a.
a
U
S
m
U
IS
S
50
-
40
-
-20
Stdev.
-18
- 16
60qJ
U
U
-14
N
-J
- 2
-10
-8
Landing Direction
30 20
-
-6
-4
10
-
- 2
0
1
2
3
4
4.
8 U
U
0
10
5
6
7
8
Exit
Figure 3.4.1.12
9
10
11
12
x
Aveage Occupancy Time During Landing
Block 2
80
Avg.Oc.Tim.
20
70
Stdev.
18
16
N
14
60
50
-
Runway 33L
_
_
.--
__12
40
10
30
8
Landing Direction
4
.
$
'
6
20
4
10
*
2
M
0
14
en
10
14
'r
W)j
0
1--
00
ON
0
-
en
q
Exit
Figure 3.4.1.13
Average Occupancy Time During Landing
Runway 33L
Block 5
Avg.Oc.Tim.
80
2
P
20
18
Sdoccup
70
Landing Direction
16
-N
60
__
__
_
_
_
_
_
14
_
50
12 '
40
10
-8
3020-
4
0
0ee
Exit
Figure 3.4.1.14
z '
Figure 3.4.1.15
Average Occupancy Time During Landing
Runway 15R
Block 7
Avg.Oc.Tim.
20
18
16
~~-N
Stdev.
U
U
U
14 12
U
U
0
41
*
mE-'
8~
S
Landing Direction
10
e
8
6
9
4
2
0
In
eq
W-4
0
ON
00
(l-
%O
Exit
Figure 3.4.1.16
Sn
14t
en
q
W-4
3.4.2 Exit Use
Figures 3.4.2.1 through 3.4.2.13 represent graphically the exit use both for all
aircraft that landed in every runway and for each aircraft (weight) class in every data
block that information about the aircraft types were available. If information was
available during data collection, the exit use per particular aircraft class is presented.
Each aircraft is classified according to its weight into one of the following three classes:
Class
Weight Range ('000 LB)
Heavy
300-900
Large
12.6-299
Small
0-12.5
Table 3.4.2
The major observations are that, as expected, the probability of exit is related to
the aircraft size (weight class). Hence, heavier aircraft tended to use exits that are located
further away from the runway threshold while smaller sized ones required shorter landing
distances and exited earlier.
A second factor that affected exit use was the specific turning angle of the exit.
This angle (which could have been acute, right, or obtuse) provides a measure of the
difficulty of using each exit. As a result, independent of runway, most aircraft tended to
prefer the use of obtuse angled (high speed) exits.
Exit Use per Aircraft Clases Runway 4R Block 1 37 Landings
35
Small
30
25
O Large
-
Heavy
20 .
15
10
Landing Direction
5 -
0
Exit
-
Figure 3.4.2.1
Exit Use per Aircraft Class
Runway 4R Block 6 23 Landings
35
30
25
* Small
20
o Large
Landing Direction
* Heavy
10
5
0
V-
1
CI
2
I
sr~
a
~.O
a
~
-t~2
00
O~
n
M
0
.Lp
-
e~
W-4 .
en~
Exit
Figure 3.4.2.2
t
O
W--4
Figure 3.4.2.3
Exit Us. Runway 22L Block 8 16 Landing.
40
35
30-
3AlI Classes
25
20
15
Landing Direction
10
5
t C) C i ak
00 r
Wten %4V- 0
in
0
Figure 3.4.2.4
Runway 22L Block 10 16 Landings
Exit Us. per Aircraft Class
40 -r
a Small
35 -
Large
30
t
25
Heavy
20 -
15t
Landing Direction
10
I
i
I
I
VI)
W-4
i
qqW-
i
'w-.---r--r--------- 11
P.
C1
-4
W-
W-
0"-
ON
00
Exit
Figure 3.4.2.5
11
r-
i
c
Vr)
,iten
N
-4
Exit Use per Aircraft Class Runway 27
Block 2 11 Landings
100
90
Small
80
Large
70
60
Heavy
50
40
Landing Direction
30
20
10
0
1
2
3
4
5
6
7
8
9
10
11
12
10
11
12
Exit
Figure 3.4.2.6
Exit Use Runway 27 Block 3 8 Landings All Classes
100
90
80
8E3All Classes
70
60
50
40
Landing Direction
30
20
10
1
2
3
4
5
6
7
Exit
Figure 3.4.2.7
8
9
Exit Use Runway 27 Block 8 19 Landings All Classes
100
90
80
All Classes
70
60
50
Landing Direction
40
30
20
10
0
1
2
7
6
5
4
3
12
11
10
9
8
Exit
Figure 3.4.2.8
Runway 27 Block 10 12 Landings
Exit Use per Aircraft Class
60 -r
50
M Small
-
Large
40
Heavy
30
20
Landing Direction
10
I
I
2
3
4
i
5
&- I
i
II
~
4 i
7
6
Exit
Figure 3.4.2.9
-
8
I
II
9
i
aI
10
i
11
12
Figure 3.4.2.10
Exit Use per Aicraft Class Runway 33L Block 5 37 Landings
60 ,50 -
40
E
Small
o
Large
Landing Direction
30
* Heavy
20
10
j
-IW-
eq
I
I-.
I
en
I
14
.r-1M
I
I
I
mrn
%O
t-
00
Exit
Figure 3.4.2.11
I.
I.rm I.r1" I.
0'
o
W-4e'4
i
I
en
I
q
Runway 15R Block 4 21 Landings
Exit Use per Aircraft Class
50 45 Small
40 -
0
35 -
Large
30 Heavy
25 -
20 Landing Direction
15 -
i
-l
l
10 -
5
I.
0-
I
I
~
'~
I
..4i
C,
I
I
O7,
0
I
I
N\Q
00
1~
':j*
r
2MII
I
ciI
Exit
Figure 3.4.2.12
Exit Use per Aircraft Class Runway 1SR Block 7 28 Landings
45 40 -
M Small
35 30 -
0 Large
25 -
* Heavy
20 15 -
Landing Direction
10 -
0
!
!
5W-4
!IIi
I
'
-
ci
-
|
0
O
00E
-
Eit
Figure 3.4.2.13
~.o
"~
~
ci
-
3.4.3 Exit Velocities
The angle of every exit plays a significant role in the exit velocity of the aircraft.
As figures 3.4.3.1 through 3.4.3.13 show, whenever the landing aircraft are using the
obtuse angled exits the exit velocities are significantly higher than the other ninety
degrees or acute angled exits. However, this is only true for high speed exits which are
accompanied with long exit segments and give the pilot room to brake (exit 6 runway 27:
38 knots and exit 5 runway 33L : 40 knots). Exit 8 of runway 4R, although it is obtuse
angled, the short exit segment that follows does not allow high exit velocities. Each
figure presents, using columns the average exit velocity, and with a line, one high and
one low value which corresponds to the average exit velocity plus or minus one standard
deviation (see figure legend). The letter H denotes a high speed exit.
Average Exit Velocity All Classes Runway 4R Block 1
0 Avg. Exit Vel.
O
-0
50
A.E.V. + SD
40
A.E.V. - SD
*
30
r
20
- Avg. Exit Vel.
Landing Direction
10
0
-I MI
I
14
H
H
W)
I.
r-00O
>
Exit
Figure 3.4.3.1
N
etn
O
Average Exit Velocity AD Classes Runway 4R Block 6
0 Avg. Ex.
60
Vel.
A.E.V. + SD
50
A.E.V. - SD
40
" Avg. Ex. Vel.
30
Landing Direction
20 -
10 4.
H
-
-
-
-
~
en
4
-
t
-
W
rO
O
00
m
.
mW.L....JnL....J ii...... I ti~
-
o.
0
.en
".
W-4
~*
-
i
ir~
-
\O
-
Exit
Figure 3.4.3.2
Average Exit Velocity All Classes Runway 4R Block 9
60
0 AvgExVel
50
A.E.V. + SD
40
A.E.V. - SD
30
" AvgExVel
20
Landing Direction
10
I
-
-
I
I
-
~~
C
t~~1-C-
00
Os
Exit
Figure 3.4.3.3
0
H
I~~1
-
-
W-4
.C4
11
W-4
W
rn
W-4
W-
Average Exit Velocity All Classes Runway 22L Block 8
60
0 AvgExVel
U,
0
50
A.E.V. + SD
A.E.V. - SD
40
0
~I.
30 ,,
"AvgExVel
Landing Direction
20.+
U
I-
10.
.
v
.0
.
'n
.I
. . . . . .
.
Cl4
Nt
1-4
0
ON
00
r-
.in.
\0
')
N
eE
Cxit
Exit
Figure 3.4.3.4
Average Exit Velocity All Classes Runway 22L Block 10
AvgExVel
>
50
A.E.V. + SD
40
A.E.V. - SD
30
3
-AvgExVel
Landing Direction
20
10
0
--
- -+ -
-H
-
+ -+
Exit
Figure 3.4.3.5
-
-+
-
--
Figure 3.4.3.6
Averag JExit Velocity All Classes Runway 27 Block 3
0
60 -
AvgExVel
50 .
AE.V. + SD
40
A.E.V. - SD
' AvgExVel
30
20
Landing Direction
10
a
'~
1
2
3
~
I
I
I
4
5
7
6
Exit
Figure 3.4.3.7
8
9
10
11
12
Average Exit Velocity All Classes Runway 27 Block 8
60
O AvgExVel
50
A.E.V. + SD
40
A.E.V. - SD
30
Landing Direction
" AvgExVel
20
.111.
10
U
a
-
0
-
------
1
2
4
3
5
7
6
8
9
11
10
12
Exit
Figure 3.4.3.8
Average Exit Velocity All Classes Runway 27 Block 10
6 AvgExVel
8 50
A.E.V. + SD
40
A.E.V. - SD
-
Landing Direction
:* 30
AvgExVel
S20
10
H
1
2
3
4
5
7
6
Exit
Figure 3.4.3.9
8
9
10
11
12
a
Average Exit Velocity All Classes Runway 33L Block 2
0 AvgExVel
50
A.E.V. + SD
40
A.E.V. - SD
30 ,
- AvgExVel
S20
Landing Direction
10 -H
IH
0
- 0-
al
Exit
Figure 3.4.3.10
Average Exit Velocity All Classes Runway 33L Block 5
o AvgExVel
60 .,
50
+
A.E.V. + SD
A.E.V. - SD
40AvgExVel
-
20
10
I
W-
I
N~
.T1T~u
I
M
1W
I
E-rn
~1111
.10.
*
%O0
r-
00
Exit
Figure 3.4.3.11
0*1
.
o-
I
-
IMA
i
-
i
-
-
Average Exit Velocity All Classes Rumway 1SR Block 4
6AvgExVel
A.E.V. + SD
50
A.E.V. - SD
40
" AvgExVel
30
230
20
Landing Direction
10 H
0-
't
m
-
0
-
01\
00
te'
ir
\0
rN
+
--
--
--
Exit
Figure 3.4.3.12
Average Exit Velocity All Classes Ruaway 1SR Block 7
60
0
M
0 AvgExVel
A.E.V. + SD
50
A.E.V. - SD
40
" AvgExVel
0
30
20
Landing Direction
'I
a-
10
-
0
O~
00
N
.E~J.rb.
a
I
\O
Exit
Figure 3.4.3.13
I
ur)
I
ll
1
e
5
e4
W-4
Figures 3.4.3.14 through 3.4.3.22 show the average exit velocities per aircraft class.
These velocities vary from aircraft class to aircraft class but the variation is not consistent
and no conclusions can be drawn in favor of one class or another.
Average Exit Velocity per Aircraft Class Runway 4R Block I
* Heavy
0
Large
E Small
.rflI
Landing Direction
.
---
I
I
-~
~~
-
~.
I' .
a~'J
-
Exit
Figure 3.4.3.14
C-4
-4
en
-
~J-
a
-
I
I
.
Average Exit Velocity per Aircraft Class Runway 4R Block 6
50 --
45 40
35
-
H
H
* Heavy
Landing Direction
-
0
30 -
25 -
Large
Small
2015 10 -
50*
I
i
I
I
I
i
i
H
|
|
00 ExitO-
|
0
I' 'II
r~
-I---
-
I
I
-
-
I
Ir
-
Eit
Figure 3.4.3.15
Average Exit Velocity per Aircraft Class Runway 22L BlocklO
50
Landing Direction
45
70
4035
EHeavy
30
OLarge
25
E Small
H
-20
15
l
10
0
Exit
Figure 3.4.3.16
Ic
Avenge Exit Velocity per Aircraft Class Runway 27 Block 2
50
45
40
H
35 -
U
Heavy
~30
0
Large
:
Small
25
Landing Direction
20
15
10
5
0
1
2
3
4
5
8
7
6
9
10
12
11
Exit
Figure 3.4.3.17
Average Exit Velocity per Aircraft Class Runway 27 Block 10
Landing Direction
50
45
g
40
Heavy
H
35
30
0
Large
* Small
25
20
415
10
5
< 0 -
1
2
3
4
5
- -i
--
6
7
Exit
Figure 3.4.3.18
i
*
8
9
10
11
12
Average Exit Velocity per Aircraft Class Runway 33L Block 2
50 -r
45 -
Landing Direction
40-
* Heavy
35 -
O Large
30 -
25 -
Small
Si
2015 10 -
an
5-
0-
(Nj
r~
'~1*
.
,
0,
,N
I
e'q
-.
a
e-
qW-4
T
Exit
Figure 3.4.3.19
Average Exit Velocity per Aircraft Class Runway 33L BlockS
50 45 -
* Heavy
40-
U Large
35 -
El Small
30 25 20Landing Direction
15 10 5 0 -*
*
a,1
W)
1O
-
00
Exit
Figure 3.4.3.20
68
o
-
e-i
o
I
~-
Average Exit Velocity per Aircraft Class Runway 15R Block 4
50 -
* Heavy
45 -
40
o Large
-
35 -
30
E
-
Small
25 -
20
-
Landing Direction
15 105.
I
I
I
I
0~
I
en
WW- (14
W1-4
0
all
I
r-
00
*R
I
'0
11t
mrn
eq
"..4
Exit
Figure 3.4.3.21
Average Exit Velocity per Aircraft Class Runway 15R Block 7
* Heavy
5045
-
40
-
0
Large
O Small
35 -
30 25 -
20
-
Landing Direction
15 10
-
5-
0-
t
I
bi
.Hn
i1----------------i
M%
00
t-
Exit
Figure 3.4.3.22
'.
In~
1I
qt
C
r-J
-
3.4.4 Velocity Profiles
3.4.4.1
Landing Velocity Profiles
Figures 3.4.4.1.1 through 3.4.4.1.13 show the landing profiles of all aircraft that
landed in each runway. The aircraft that used a particular exit are grouped together. We
can observe the different exit velocities and the higher or lower deceleration that occur,
depending on the angle and the location of each exit. We must note the fact that some
aircraft actually speed up after the runway threshold.
Figure 3.4.4.1.1
Landing Velocity Profile Runway 4R Block 6
1.2
X
X
0.8 ----------------------
--
X
U.X
yxX
o
X
a 0.4 ------------- X --
- -
Mean Exit 8
'
Mean Exit 12
--------
0.6 ------------------ X'--
-------------
T
h
r
e
-- 9
h
-
3
Mean Exit 13
X-
Mean Exit 14
0
----------------------------0.2
d
0(
e
en e
C'q
C1
Ni
0
Ci
-
"I
.- 1
-
cc
-4
Radar Hits from Run way Threshold
Figure 3.4.4.1.2
Landing Velocity Profile Runway 4R Block 9
1.2
1
0.8
-'
A
- ---------
0.6
-------
0.4
-X-
- ..
h
r
e
----
S
-
Mean Exit 7
Mean Exit 8
Mean Exit 11
--
-----..
-
Mean Exit 12
0.2
ON'No
C1eqC4C
en
0
r-
IR
-q
1-
1-
-1
e'i
N
00
r-
0
rM
1-
-4
Radar Hits from Runway Threshold
Figure 3.4.4.1.3
72
OONC
e
C4
Landing Velocity Profile Runway 22L Block 8
Xh
r
Mean Exit 6
Mean Exit 8
----
-
-
-- O--
Mean Exit 10
-----
Mean Exit 11
0.2
eq
0c
I~ en
Il
0
1%0
C4I
C4i N
Wc
-
I
-.
0
%o
eC4
W-
C4
.C
0
qT W0
V-
"-
Radar Hits from Runway Threshold
Figure 3.4.4.1.4
1-
NO
N
C
0
N
en
Landing Velocity Profile Rmnway 22L Block 10
1.4
1.2
.
0.8
---0.6
Mean Exit 6
-X-
0.4
Mean Exit 7
0
Mean Exit 10
-- -
Mean Exit 11
0.2
R -4
M~ M
00
C4
'n
C N
C7i% 1%0 M
-
-4
-
o
t~-
q
-
-4
eN
i)
W
Wc -
Radar Hits from Runway Threshold
Figure 3.4.4.1.5
74
-4
q
r-
0
-
-4
ei
mllililiih,
~
1111,
INM
i IIIiliii
1,101111i
Landing Velocity Profile Runway 27 Block 2
1.4
------------------------------
-----------------------
--------------
1.2
1 -
---
0.8 -
-
-
-
---
---
------
-------
-
m-----
-------
----------
--- -----
W-------------
M--
T
------------- hr
e
0.6 - ------
S
1
b
0.4
-- -- Mean Exit 6
d
0.2 -4-----------------------4------------------------------
i
i i
!i
I
I
I I
SiilIili
eq
0%
C4
-.
I I I II
I
11111a
%O~0
I
I
i i i.,
I
II
I
Ii
e
II I II II II I II II I I I II I I I II II I I
mliii
I I
-
N
ii
I
Iloa umimi
a i l
uIn
1--4
00
-
I iiiimmiiui
I I aI
"-
Radar Hits from Runway Threshold
Figure 3.4.4.1.6
I
r-
.qt
1-
I
0
N
mliii,
g o
1
1
m
C1
r4
1
Landing Velocity Profile
Runway 27
Block 3
1.2
1
>0.8
-e
.C
0.6
Z
T
h
r
-0
-------
0 0.4
---
---
0.2
o
t-
"qf
1-
eqi ci
00
-4
in
N
'-4
-4-
ON
~
*10
Radar Hits from Runway Threshold
Figure 3.4.4.1.7
cias
00
Landing Velocity Profile Runway 27 Block 8
1.2 -r----------------------------&-------------------------
1- ---------------------------- ----
1T
.
>0.8 - --------------- ----- -------- ---
eO.r
-ee
0.6
h
- --------------- ------------
-
-Mean Exit 8
0
d
0.2 ---
------------------------- ---
191
1111911 111 111 H11
0
a'
N
-
Radar Hits from Run w'ay Threshold
Figure 3.4.4.1.8
-4
00
-.
4
C4
-.
14H
I
C4
Landing Velocity Profile Runway 27 Block 10
1
0.8
0.6
h
r
e
0.4
S
-------------
0.2
Radar Hit from Runway Threshold
Figure 3.4.4.1.9
Landing Velocity Profile Runway 33L Block 2
1.6
1.4
1.2
1
0.8
3
Mean Exit 5
0
Mean Exit 8
0.6
-X-
a---------- b-.
0.4
Mean Exit 10
--
- Mean Exit 12
0
-q
0.2
.t
-4
00
kn
eq
C,
r-
0
%
rC4
in
Radar Hits from Runway Threshold
Figure 3.4.4.1.10
79
t-
0
Figure 3.4.4.1.11
80
Landing Velocity Profile Runway 1SR Block 4
1
-
0.8
C
*)
-------------
0.6
-- +--
Mean Exit 7
- Mean Exit 10
-----------------
0.4
-X-
9--
Mean Exit 11
0.2
00
e.
NRadar
e
Ca o
00
'.
".4".4".
e4
o0
H -
f
oo
e
R
R-
ei
0
Thr
c-
e
Radar Hits from Runway Threshold
Figure 3.4.4.1.12
'
o
0
o
Ce
Figure 3.4.4.1.13
82
hi"I
3.4.4.2
Final Approach Velocity Profiles
In the final approach velocity profile figures ( 3.4.4.2.1 through 3.4.4.2.13) we
observe that in most runways, there is a small deceleration during the final approach. In
some runways, 27 in particular, this deceleration is quite significant (Figure 3.4.4.2.6). In
the same runway, during night operations (Figure 3.4.4.2.8) we see much more smooth
final approach velocity. In runway 15 R, we note that even under different weather
conditions, aircraft seem to accelerate before the runway threshold.
Overall, the standard deviations of the landing velocities fall between a value of
0.2 for a period of approximately 10 radar hits before the threshold and from then on it
increases significantly. This could be due to the changing size of the available number of
data points (radar hits), as further away from the threshold some aircraft target are not
picked up by the surface radar.
Runway 4R Block 1
Final Apprch Velocity Profile
0---
10
--- --- --- --- ----------------------------- - --- .--- 09
S0.8 ----------------------------------------------------------0.7 -------------------------- ean-----------------------------'----------------------------
0.6 --------------
I
~0.18..0.3 -------------------------------------------------- --------
j----
0 .2 ---------------------------------------------
0.5-----------
-------------
--------------
0
1
2
3
4
5
6
7
8
9
10
11
12
Radar Hits from Runway Threshold
Figure 3.4.4.2.1
13
14
15
16
17
-maw"
Final Approach Velocity Profile
Runway 4R Block 6
1.2
1
1-
0.8
A
0.6
.C
0.4
0.2
0
1
2
3
4
5
6
7
8
9
10
Radar Hits from Runway Threshold
Figure 3.4.4.2.2
Final Approach Velocity Profile
Runway 4R Block 9
1.2
1
~;m.
0
0.8
-0-
U
Mean
0.6
-- --------------..
-O-*---Stdev.
0.4
- - - ------------.....................-------
-.-..-----
-.-
~1
0.2
---
--
----
-
-
----
I-
I-,
I-
0
1
2
3
4
5
6
7
8
9
Radar Hits from Runway Threshold
Figure 3.4.4.2.3
84
10
11
12
Pinal Approach Velocity Profile
1.2
S
Runway 22L Block 8
----------------------------------------------------------
--
0.8
-.
-
.-- --
---
.---
-
.......---
.-...
S.
Mean
----------------------
0.6 ----------------------
W3
Stdev.
----------------------------------- ----------- -----------
d0.2
0 r
1
2
3
4
5
6
7
8
9
11 12 13 14 15
10
16
17 18
19
Radar Hits from Runway Threshold
Figure 3.4.4.2.4
Final Approach Velocity Profile
1.2
Runway 22L Block 10
-----------------------------------------------------------
0.8 ------------------------------------------------------0-Mean
---.....---Mean-
f0.6 ------------------------
- Stdev.
-3
-----------------
-
10.4 ---------------------
0.2 ----------------------------------------------------------
0
1
2
3
4
5
6
7
8
9
10
11
12
Radar Hits from Runway Threshold
Figure 3.4.4.2.5
85
13
14
15
16
Final Approach Velocity Profile
Runway 27 Block 2
1.4 .------------------------------------------------------------
-------------------
0.8
0.6
-S-----------...---
0.4
....... -
0.2
----
-- -- -- -- -
-=..---
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- ---
.1.2
Mean
-
Stdev.
--
...- --..---..
---- .. -...--.-- ..-- --
-----
- -
.--- - ----
-
------- m--------------------------------------------------0~~~~3
0
1
2
4
3
5
.
6
7
8
............
9
10
11
i
I
12
13
I
14
15
I
16
17
I
18
19
20
Radar Hits from Runway Threshold
Figure 3.4.4.2.6
Final Approach Velocity Profile
1.2
Runway 27 Block 3
---------------------------------------------------------1
---
-m-
-'"''=
-=--'-
===-:.3-;:=.-----.-
- - - - - - - - - - - - - - - - - - - -
- - - - - --
AI
.------------------- ------------------------------------
S0.8
---o---Mean
0.6 ------------------ --
-3-
-----------------------
Stdev.
-----------------------
e0.4 --------------m------
0.2 .-----------------------------------------------------------0
1
2
34
5
6
7
8
9
10
11
12
13
14
Radar Hits from Runway Threshold
Figure 3.4.4.2.7
86
15
16
17
18
19
Pinal Approach Velocity Profile
Runway 27 Block It
1
--
- --
--------
--
--
--
--
--
--
--
----
-
-
-
-
-
-
-
-
-
-
-
-
-
0.9
----------------------m-----------------------------0.8
------------- ----- --------m---------------------m----------0.7
0.6
.--------------------- N
e n ---------------------0.5 ----------------- - - -- -- Stdev.-m
0.4
-------------------------------------------------------0.3
0.2 -----------------------------------------------------------------
-
---
0.1
---------------------------Ma
---
- --
---
---.---
-----------------
--------
0
1
2
7
8
9
10
11
12
Radar Hits from Runway Threshold
Figure 3.4.4.2.8
Final Approacb Velocity Profile
Runway 27 Block 10
1.2
----------------------------------------------------------
0.8
---------------------
---------------------
8
0.4
-
Mean
-O--
Stdev.
------------------------
S0.2 ------------------ ---------------- ----------------------0
1
2
3
4
5
6
7
8
9
10
11 12
13 14
15 16 17
Radar Hits from Runway Threshold
Figure 3.4.4.2.9
87
18 19 20
Final Approach Velocity Profile
1.2
Runway 33L Block 2
-------------------------------..----....----...---..--..--.-
8
.---
--.
I"
0.8
------------------------------------------------------------ ---
S0.6 --------------------
Mean
-------------------
---
---O--Stdev.
o0.4 ---------------------
.---------------
d .2
- -.
---------------------------------
-
-.
----...
.........--
...-
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Radar Hits from Runway Threshold
Figure 3.4.4.2.10
Final Approach Velocity Profile
1.2
.
--------------------1- - --
'c 0.8
---
Runway 33L Block 5
--.---..-..--..-....---..-------...
--------------------...-
-
-.------.--
-- -- -- - --------- - m- -- - --- -----
0.6 ------------
-
m---.- --
--- - --....--
..----
...--- -
.--
-Mean
---
----.---.-- .. m---...----
Stdev.
e0.4 --------------------S 0.2 . -------------- --
-.
- ..----...
--
--
.
-------------
- -
-------
0
1
2
3
4
5
6
7
8
9
10
11
12
Radar Hits from Runway Threshold
Figure 3.4.4.2.11
88
13
14
15
16
17
Final Approach Velocity Profile
Runway 1SR Block 4
1.4 ------------------------------------------------------------
31
.---------------------------------------------------------
0.8
--- ------------------------ -----------
----------------
-------
--------------
0.6 -- -----------------e---Mean
0.4 -- ---------------
------------------------13
Stdev.
-0 ---------------0
i
2
1
3
4
-------------------------
7
6
5
9
8
10
11
12
13
Radar Hits from Runway Threshold
Figure 3.4.4.2.12
Final Approach Velocity Profile
Runway 1SR Block 7
1.4 ------------------------------------------------------------
---..
- : :...
--.
- - 1.2~~~~
.2
-----------------------------------------
.. =......-----
---
0.8 - --- -------------------------- -----
-
0.6 ---- ---------------------------- ----
--- D--
Mean
------
Stdev.- ------
0.4 -- ------------------------------ -------------------------
=0.2
---
-- -------------------------------
-------------------
0
1
2
3
4
7
6
5
8
9
Radar Hits from Runway Threshold
Figure
3.4.4.2.13
89
10
11
12
13
3.5 Intersection Analysis
3.5.1 Intersection Crossing Times
When an aircraft approaches an intersection it is either cleared to cross it by the
ground controller, or it is instructed to stop or slow down to allow another aircraft to
cross in front of it. Occasionally, in periods of heavy traffic a pilot will have to wait in a
queue to cross a particular intersection or possibly wait for a queue of aircraft to pass
through an intersection.
Figure 3.5.1.1: Typical Intersection
Due to the complexity of the runway and taxiway system at Logan airport, a
departing or arriving aircraft has to cross a significant number of intersections in its way
to the gate or departing runway. In order to measure the intersection crossing time as
C
-AA
Cat
accurately as possible a distance of fifty meters before and after the intersecting runway
or taxiway centerline was chosen. Since the radar hits are skin returns from the center of
the aircraft' s fuselage, such a distance would ensure that the calculated crossing time
would include the initial crossing of the front part of the aircraft and will end after its tail
has cleared the crossing runway or taxiway (Figure 3.5.1.1).
The calculated crossing time was split in two segments. The first (time 1) being
the time from the start until the aircraft crosses the intersecting centerline and the second
segment (time 2) from the centerline until the aircraft clears the runway or taxiway. The
following table lists the series of airport links corresponding to each intersection number.
Intersection
Series of Links
1
A16 A17 A18
2
A02 A01 A19
3
A22 A23 A48
4
A18 A24 A46
5
A08 A09 A44
6
A74 A75 A83
7
A52 A51 A86
8
A48 A47 A70
9
A24 A46 A60
10
A44 A43 A00
11
A44 A43 A10
12
A35 A43 A00
13
A35 A43 AlO
14
A35 A42 A20
Table 3.5.1
Figures 3.5.1.3 through 3.5.1.12 show the average crossing times along with the
standard deviations for every intersection in the ten blocks of collected data. As figures
3.5.1.13 and 14 show there is a significant difference in average crossing time depending
in the runway configuration and thus in the direction of use of some intersections. For
example, when intersections 10, 11, 12, 13 and 14 are used in the inbound direction
(towards the terminal area), usually after arrivals in runway 27, the crossing times seem
to be much smaller compared to those of departing aircraft which use the same
intersections but in the opposite direction (outbound), and often have to form a queue
while waiting to depart from runway 9 and thus cross these intersections very slowly.
Similarly in intersection 6 the inbound direction of crossing is much quicker (aircraft
landing on runway 4R) that the outbound one (aircraft waiting to depart from 22L and
22R).
Comparing the crossing times of the two different segments of each intersection
(time 1 and time 2), we observe that usually when an intersection is used in the inbound
direction time 2 is larger than time 1 and when it used in the outbound time 1 is larger.
This could be possibly due to the fact that when a pilot is on his way to the gate, after
crossing the intersection it has to slow down since the connecting taxiway segments
A75-A83, A51-A86, A47-A70 etc. are short as they intersect with the circuferential outer
taxi lane which is often congested. On the other hand, in the outbound direction usually
time 2 is smaller than time 1 probably because the connecting taxiways that lead away
from the terminal area are longer and therefore the pilot accelerates faster.
Figures --- through --- show the average crossing times per aircraft class (size) for
intersections where ten or more aircraft crossed them. Larger aircraft are heavier and
logically should have longer crossing times but the graphs show this is the case only in
few blocks of data (block 1).
Block 1
Average Intersection Crossing Times
50
45
40
35
-
-
L-r-
E3 Mean Time 1
-
o Mean Time 2
-
IfI
30
Stdev Time 1
25
20
* Stdev Time 2
-
15
-
10
-
5
0
L7-[L77HI~bn
....
-
C1
M
~' t
I
V)
tr-
'
00
ON
0
I
c~
-
-
-
-
Intersection Number
Figure 3.5.1.3
Average Intersection Crossing Times
Block 2
62
E) Mean Time 1
EMean Time 2
Stdev Time 1
Stdev Time 2
LFE~
I e
I
I
~
n
n
j
_r.fl- A,,
Lm F-J
-. -"
r--r---i
m1--Ir~
~
~0
r---
00
0~
0
r'-r---
-
e'~
-
Intersection Number
Figure 3.5.1.4
94
-
Figure 3.5.1.5
Average Intersection Crossing Times
W-
eq
e
t
n
00
M\
Intersection Number
Figure 3.5.1.6
0W-
Block 4
V-
-
C4I
-
en
V-
qt
W-
Average Intersection Crossing Times
Block 5
50
liEl Mean Time 1
45
4035._
O
Mean Time 2
E Stdev Time
25
*30.
1
--- -
Stdev Time 21
20s
0
0
15 10q
-
M~
lq
In
%0
00
(ON
0
1 enI
-
Intersection Number
Figure 3.5.1.7
Average Intersection Crossing Times
50
45
ii
40
Block 6
Mean Time 1
o- Mean Time 2
35
30
Stdev Time 1
25
20
15
10
-
W-4
C14
Stdev Time 2
M
It
kn
O
t-
00
ON
Intersection Number
Figure 3.5.1.8
-
-
-
-
-
Average Intrsection Crossing Times
Block 7
50
45
40
* 35
30
25
20
15
10
5
0
q
-
en
'
o
(
00
o
0
-
e
rn
Intersection Number
Figure 3.5.1.9
Average intersection Crossing Times
Block 8
50
45
Eii mean Time 1
40
35
30
0
Mean Time 2
Eil Stdev Time 1
25
20
15
SStdev Time 2
10
5
0
T-
CMJ CO
e
LO)
Co
,.
co
o0
0
1v-
Intersection Number
Figure 3.5.1.10
1-
C
CO
r
1
Averge Intersection Crossing Times Block 9
68
0
Mean Time 2
E
Mean
Time
2
Stdev Time 1
Stdev Time 2
4
nt er s0ei
en
00 Nme
o
-
-
-
Intersection Number
Figure 3.5.1.11
Average Intersectio Crossing Times
50
45
Mean Time 1
40
DE
Mean Time 2
35 30
E
-
Stdev Time 1
25 -
202Stdev
Time 2
15
10-
0Intersct
Nu m b
N~~
t
in
r-
0-ON
Intersection Number
Figure 3.5.1.12
Block 10
-
Average Intersection Crossing Time
Inbound Direction
O Block3
Tim. 1
o Block3 Tim. 2
Block8 Tim. 1
Block8 Tim. 2
BlocklO Tim. 1
BlocklO Tim. 2
'4
11
14
12
Intersection
Figure 3.5.1.13
Outbound Direction
Average Intersection Crossing Time
O Block1
Tim. 1
Blocki Tim. 2
Block4 Tim. 1
Block4 Tim. 2
Block6 Tim. 1
O Block6 Tim.
2
E Block9 Tim. 1
10
11
12
13
Intersection
Figure 3.5.1.14
14
il
Block9 Tim. 2
Average Intersection Crossing Time
Inbound Direction
50.
45.
OiBlock1 Tim. 1
40-
O Block1 Tim. 2
35
30.
Block6 Tim. 1
25.
Block6 Tim. 2
20.
15
Block9 Tim. 1
10.
5-
0.
-
-r-iA
IJ Block9 Tim. 2
.................
I
6
Intersection
Figure 3.5.1.15
Average Intersection Crossing Time
Outbound Directic
ii
Block2 Tim. 1
o Block2 Tim. 2
50 ,
45 -
Block3 Tim. 1
40 35 .
30 -
* Block3 Tim. 2
Block5 Tim. 1
25 -
E Block5 Tim. 2
20 15
M Block8 Tim. 1
10 -
M Block8 Tim. 2
5-
M, 111111 RM VIA,
0-
BlocklO Tim. 1
6
Intersection
Figure 3.5.1.16
100
* BlocklO Tim. 2
per Aircraft Cia
Average Intersection Crossing Times
Block 1
15
12-
0
*
6
8
Intersection
Figure 3.5.1.17
Average Intersection Crossing Times
per Aircraft Class
* Avg. T1 Heavy
o Avg. T2 Heavy
Block 2
Stdev T1 Heavy
Stdev T2 Heavy
Avg. Ti Large
0
Avg. T2 Large
Stdev T1 Large
-x
Stdev T2 Large
Avg. T1 Small
E Avg. T2 Small
Intersection
Figure 3.5.1.18
101
* Stdev T1 Small
Average Intersection Crossing Times
per Aircraft Class
Block 4
O
Avg. TI Heavy
Avg. T2 Heavy
Stdev TI Heavy
Stdev T2 Heavy
Avg. Ti Large
E Avg. T2 Large
* Stdev T1 Large
Stdev T2 Large
Avg. Ti Small
4
Avg. T2 Small
9
Intersection
Stdev T1 Small
Figure 3.5.1.19
Average Intersection Crossing Times
per Aircraft Class
Block 5
N Avg. TI Heavy
E3 Avg. T2 Heavy
Stdev Ti Heavy
Stdev T2 Heavy
Avg. TI Large
Ei Avg. T2 Large
E Stdev Ti Large
01 Stdev T2 Large
* Avg. T1 Small
3
7
8
Intersection
Figure 3.5.1.20
102
* Avg. T2 Small
* Stdev T1 Small
3.5.2 Intersection Use
The following table provides information about the number of aircraft that used
each intersection. Figures 3.5.2.1 through 3.5.2.4 show the intersection use under the four
most popular runway configurations at Logan airport. As we can see, the use of a specific
exit is closely related to the operating runway configuration.
Number of Aircraft Using Each Intersection
Intersection Block Block Block Block Block Block Block Block Block Block
1
2
3
4
5
6
7
8
9
10
1
0
2
0
0
6
0
0
0
1
0
2
0
15
0
0
23
0
0
0
0
0
3
0
5
0
4
21
0
-7
0
0
0
4
0
2
0
12
1
0
9
0
0
5
0
13
3
0
1
0
0
1
0
0
4
6
13
4
25
2
7
26
0
36
6
45
7
0
18
0
7
16
1
6
1
1
1
8
11
6
3
5
20
3
11
3
11
4
9
8
30
0
11
50
0
11
2
6
10
0
9
2
0
1
0
0
3
0
3
1
11
0
3
2
0
0
0
1
4
0
5
12
11
0
6
25
0
9
7
8
9
3
13
4
0
1
4
1
3
2
7
1
6
14
11
1
1
11
0
10
3
5
8
0
Table 3.5.2
103
Number of Aircrafts Using Each Intersection
Configuration:
Arrivals 4R, 4L and Departures 9. 4L
Block1
0Block6
Block9
I
C14
en
IT
I
M
%10
W
t-
00
a
I
0
Ch
-
".4
-
-4
Intersection Number
Figure 3.5.2.1
Number of Aircrafts Using Each Intersection
Configuration:
Arrivals 33L and Departures 33L, 22R
50
45 40-
-
Block2
35 -
0 Block5
30.
25
20
-
15 10 -
ft I
0
I
-
I
e~
~
-
~
-i
I
~
I
mr~
iE~
I
~.O
t-=
00
Intersection Number
Figure 3.5.2.2
104
0
-
I
1
M
111111111111101110111111,
M1111,ji
I H III d
. ...
Number of Aircrafts Using Each Intersection
III
Configration:
Arrivals 27, 22L and Departures 22R, 22L
i
______________________________________
________________________________
I MBlock3
Block8
BlocklO
Z ru..11 J MJ I
"-
e.14 en
%n~
1.0
t-
00
ON
0-
.4
-
1
-
M~e
-
V-
Intersection Number
Figure 3.5.2.3
Number of Aircrafts Using Each Intersection Configuration:
Arrivals 15R and Departures 9, 15R
50
45,,
U
40m
Block4
35
.E3 Block7
30
25
-
S20
E 15
S10
1
5
Intersection Number
Figure 3.5.2.4
105
W
IiII
3.6 Taxiway Analysis
3.6.1 Taxiway Average Velocity
The average velocity of an aircraft moving on an airport taxiway system depends
on many factors. Before the analysis of the collected data, we expected that the distance
of the taxiing segment would be a significant determinant of this velocity. Usually when
pilots are moving on a short segment, prefer to taxi slowly since they expect soon to
arrive at an intersection and might be instructed by the controller to stop for crossing
traffic. On the other hand when a pilot sees that he has a long stretch in front of him with
no imminent intersection, he taxies at higher speeds.
The location of the taxiway segment should also play an important role. Taxiways
far away from the terminal area are more likely to exhibit higher average velocities since
they tend to be less congested and their surrounding areas are usually free of obstacles.
Other variables that affect the taxiway velocities, are the complexity of the taxiway
system at the particular airport and the level of familiarity that each pilot, who operates
there, has with the system. The first variable usually remains constant while the second
one can vary, and cannot be very easily quantified.
Trying to test if the taxiway length and location relates to the average taxiway
velocity, we categorized each taxiway link that did not belong to a runway or was not an
exit link, into two groups. Those links that were shorter than 500 meters were assigned a
letter S and those that were longer a letter L. Each taxiway was also assigned either a
letter C (close) if it was located inside the outer taxilane, or a letter F (far) otherwise.
106
Id
1,14 ,
,
j1
'1411
11,
1,111"
'1
Figure 3.6.1.1 shows the average velocity of all taxiways for each data block
independent of segment length or location. The velocities range between 7 and 16 knots.
However, standard deviations vary from 6 to 22 knots. Data block 3 exhibits the lowest
average velocity for its taxiways (7 knots), possibly due to the heavy traffic of that time
period. To traffic congestion can be also attributed the low velocities that we observe in
data block 4. Bad weather conditions (thunderstorms and fog) are the probable reasons
for low velocities in blocks 1 and 9.
Average Velocity in Taxiways
35
30.
Mean
25
Stdev.
20
1
2
3
4
5
6
7
8
9
10
Data Block
Figure 3.6.1.1
The results of the previous taxiway categorization can be seen in figures 3.6.1.2
and 3.6.1.3. Longer segments almost always display higher average velocities than the
shorter ones. We must note though that in periods of heavy traffic the differences in speed
between longer and shorter taxiways become smaller. As figure 3.6.1.3 shows, taxiways
that are located far from the terminal area, in data blocks 1, 6, 9, 4 and 7, have higher
average velocities while in the other blocks lower. It is interesting to note that blocks that
have higher velocities, the runway configuration is the same (block 1, 6, 9 arrivals in 4R
107
departures from 9). The same pattern (same configuration for all blocks that exhibit
similar velocity characteristics) occurs in the other blocks of data, where the combination
(higher velocity - taxiway location) is opposite.
I
Length : Short I Long
Average Velocity in
Taxiways
35
0
30
25
20
4
I
II
o Sd Short
I
15
,
* Mean Short
I
I
Mean Long
S10
Sd Long
5
0
.3
N en~
IT
in
vC
r-
00
o
0
Data Block
Figure 3.6.1.2
Figure 3.6.1.4 shows two groups of taxiways. In the first group, belong taxiways
that are located close to the terminal area and are short in length, while in the second one
the taxiways that are located further away and are longer. Here, the differences in
velocities between the far and long and the close and short becomes even larger in favor
of the longer and further away ones compared to the previous two figures. However,
these differences, in the blocks where close and short taxiways have higher velocities,
become smaller.
Overall, we can conclude that there exist a close relationship between the length
of the taxiway and the taxiing velocity. The location of the taxiway segment seems to be
also critical. We must also note that traffic congestion has a more deleterious effect on the
average taxiing velocity than bad weather conditions.
108
Average Velocity in Taxiways
Location
Close / Par
i0
Mean Close
Sd Close
Mean Far
0
* Sd
Sd Far
Fa
'U
Eu
0
W-4
Cq
n
"t
Dtna- Bo
%0
00
0
Data Block
Figure 3.6.1.3
Average Velocity in Taxiways Location: Close I Par Length:
Short / Long
35
W
130-
Mean C &S
S25-
0 Sd
S20-
15-
Mean F &L
n
asU
&S
t0
SdF&L
S5
0
Data Block
Figure 3.6.1.4
109
3.6.2 Taxiway Use
Figure 3.6.2.1 through 3.6.2.10 present the use of the taxiway segments that
constitute the inner and outer taxilanes. All data blocks show an almost identical taxiway
use no matter what is the runway configuration. The most often used taxiway links are
B03-B04 and B04-B05 of the inner taxilane. Only block 3 demonstrates a higher
percentage wise use of the outer taxilane, probably due to the heavy surface traffic of that
day.
In figure 3.6.2.11 through 3.6.2.20 the use of the supporting taxiways is presented.
As supporting taxiways are classified all the taxiway links that do not belong to either a
runway or the inner and outer taxilanes, but feed traffic to the terminal and runway areas.
A very strong relationship between the use of the these taxiway links and the particular
runway configuration seem to exist, as figures of data blocks with the same configuration
seem identical.
110
'TI
B08A92
B09A93
A50A20
A35A42
A97A98
A98A80
A80A99
A99B00
BOOBO
BO1B02
B02B03
B03B04
B04B05
B05B06
B06B07
B07B08
B08B09
B09A95
A95A96
A97A79
A79A81
A81BIO
B10A82
A82A83
A83A84
A84A85
A85A86
A86A70
A70A60
A60AOO
AOOA1O
A1OA20
A50A91
A91A92
A92A93
A93A94
A94A95
Number of Aircraft
B08A92
B09A93
A50A20
A35A42
A97A98
A98A80
A80A99
A99B00
BOOBO
BOIB02
B02B03
B03B04
B04B05
B05B06
B06B07
B07B08
B08B09
B09A95
A95A96
A97A79
A79A81
A81B1O
B10A82
A82A83
A83A84
A84A85
A85A86
A86A70
A70A60
A60AOO
AOOA1O
A1OA20
A50A91
A91A92
A92A93
A93A94
A94A95
0)
tA
0
U
Number of Aircraft
r
..
A79A81
A81B10
B10A82
...
A82A83
A83A84 ----A84A85 ...
A85A86
A86A70
A70A60....x.
A60A0O
AOOAO ....
A1OA20
A50A91 ...
A91A92
A92A93
A93A94
A94A95
A97A79
B08B09
B09A95
A95A96
B07B08
B05B06
B06B07
B03B04
B04B05
B09A93
A50A20
A35A42
A97A98
A98A80
A80A99.......
A99B00
BOOBOI
B01B02
B08A92
Number of Aircraft
9
-
0%
~
-
~1.
B08A92
B09A93
A50A20
A35A42
A97A98
A98A80
A80A99
A99B00
BOOBOI
BO1B02
B02B03
B03B04
B04B05
B05B06
B06B07
B07B08
B08B09
B09A95
SA95A96
A97A79
t
A79A81
A81BIO
B10A82
A82A83
A83A84
A84A85
A85A86
A86A70
A70A60
A60AOO
AOOA1O
A1OA20
A50A91
A91A92
A92A93
A93A94
A94A95
C: 8
s
8
C8t
Number of Aircraft
B08A92
B09A93
A50A20
A35A42
A97A98
A98A80
A80A99
A99B00
BOOBOI
BO1B02
B02B03
B03B04
B04B05
B05B06
B06BO7
B07B08
B08B09
B09A95
A95A96
A97A79
A79A81
A8B1O
B1OA82
A82A83
A83A84
A84A85
A85A86
A86A70
A70A60
A60AOO
AOOA1O
A1OA20
A50A91
A91A92
A92A93
A93A94
A94A95
... ..... .. . . .
" . """""""""......
...................................................
Number of Aircraft
to
-
96
-
C
-I
O|l
x
t
S
A79A81
A81B1O
B10A82
A82A83
A83A84
A84A85
A85A86
A86A70
A70A60
A60A00
AOOA10
A1OA20
A50A91
A91A92
A92A93
A93A94
A94A95
A97A79
B02B03
B03B04
B04B05
B05B06
B06B07
B07B08
B08BO9
B09A95
A95A96
B01B02-
B08A92
B09A93
A50A20
A35A42
A97A98
A98A80
A80A99
A99B00
B300B301
BOOBOI
----
-----
-====..-.-..
.......
.
Number of Aircraft
(D
::
I
m
"
g
A95A96
A97A79
A79A81
A8iBIO
B10A82
A82A83
A83A84
A84A85
A85A86
A86A70
A70A60
A60AOO
A00A1
A1OA20
A50A91
A91A92
A92A93
A93A94
A94A95
SB09A95
B053B06
B06B07
B07B08
B08B09
B
--------...
-.........----..........--.
--.
...............
BO8A92
B09A93
A50A20 .------A35A42 -----A97A98
A98A80
A80A99.
A99B00 .
B00301 .........
B01B02 ....
B302B03
--
Number of Aircraft
*
-
-j
A80B10
A20A40
A39A37
A37A31
B04A60
A18A24
A16A17
A33A32
A32A31
A18A19
A02AO1
A02A04
A04A07
A07A90
B06A1O
A35A43
A44A43
B03A70
A48A47
B14B13
A98A81
B00A83
A74A73
A73A71
A71A69
A67A66
A66A63
B02A86
A99A82
B05AOO
A35B13
A34A33
B06A50
..........
o C0L C
*-
ssa e s :
Pt
o
0
~J
------------------------------------
LA-/
Number of Aircraft
-
-
B06A50
A34A33
A35B13
B05AOO
A99A82
B02A86
A66A63
A67A66
-
-
-
-
-
-
-
A73A71
A71A69
-
A74A73
-
A98A81
B00A83
B14B13
A48A47
B03A70
A44A43 *
A35A43
A07A90 "
B06A1O
A02AO1
A02A04
A04A07
A18A19 "
A32A31
A33A32
B04A60
A18A24
A16A 17
A37A31
ASOB1O
A20A40
A39A37
"g
p
0
I
U
.A
o
~
k~
0
~Jm
Number of Aircraft
0
~Ju
-
9
~1.
A80BO
A20A40
A39A37
A37A31
B04A60
A18A24
A16A17
A33A32
A32A31
A18A19
A02AO1
A02A04
A04A07
A07A90
B06AIO
A35A43
A44A43
B03A70
A48A47
B14B13
A98A81
B00A83
A74A73
A73A71
A71A69
A67A66
A66A63
B02A86
A99A82
B05AOO
A35B13
A34A33
B06A50
Ig
.:.:.;
........
U
0.A0
IN)3
0
~A
0
~A
-------------MM
tJm
-
Number of Aircraft
0
A80B1O
A20A40
A39A37
A37A31
B04A60
A18A24
A16A17
A33A32
A32A31
A18A19
A02AO1
A02A04
A04A07
A07A90
B06A1O
A35A43
A44A43
B03A70
A48A47
B14B13
A98A81
B00A83
A74A73
A73A71
A71A69
A67A66
A66A63
B02A86
A99A82
B05AOO
A35B13
A34A33
B06A50
0
~A
0
I
M
~
3
RON Pg
1-"
Number of Aircraft
00
-*9
021
A80B1O
A20A40
A39A37
A37A31
B04A60
A18A24
A16A17
A33A32
A32A31
A18A19
A02AO1
A02A04
A04A07
A07A90
B06A10
A35A43
A44A43
B03A70
A48A47
B14B13
A98A81
B00A83
A74A73
A73A71
A71A69
A67A66
A66A63
B02A86
A99A82
B05AOO
A35B13
A34A33
B06A50
0
~
I
o
-
U
U
~A
LA
0
----------
0)
Number of Aircraft
A8OB10
A20A40
A39A37
A37A31
B04A60
A18A24
A16A17
A33A32
A32A31
A18A19
A02AO1
A02A04
A04A07
A07A90
B06A1O
A35A43
A44A43
B03A70
A48A47
B14B13
A98A81
B00A83
A74A73
A73A71
A71A69
A67A66
A66A63
B02A86
A99A82
B05AOO
A35B13
A34A33
B06A50
U
ti
i
~
[
I
............
.............
U
7:.....
7 ........
.
..................
.... .
..........
........
.. ........ ............
.......
.............
-
Number of Aircraft
A18A24
A16A17
A33A32
A32A31
A18A19
A02AO1
A02A04
A04A07
A07A90
B06A10
A35A43
A44A43
B03A70
A48A47
B14B13
A98A81
B00A83
A74A73
A73A71
A71A69
A67A66
A66A63
B02A86
A99A82
B05AOO
A35B13
A34A33
B06A50
B04A60
A80BIO
A20A40 I
A39A37
A37A31
I
*
I-
U
-
Number of Aircraft
T_
A35B13
A34A33
B06A50
B05AOO
A99A82
B02A86
A66A63"
A71A69
A67A66
A73A71
-
-
-
-
A80B1O
A20A40
A39A37
A37A31
B04A60
A18A24
A16A17
A33A32
A32A31 7
A18A19
A02AO1
A02A04
A04A07
A07A90
B06A10
A35A43
A44A43
B03A70
A48A47
B14B13 "
A98A81
B00A83
A74A73
Z
Ot)
00O)
-I.."
:MEMO
I II
CA
Number of Aircraft
A73A71
A71A69
A67A66
A66A63
B02A86
A99A82
B05AOO
A35B13
A34A33
B06A50
A74A73
A48A47
B14B13
A98A81
B00A83
B03A70
A07A90
BO6A10
A35A43
A44A43
A04A07
A02A04
A16A17
A33A32
A32A31
A18A19
A18A24
A80B1O
A20A40
A39A37
A37A31
B04A60
Aircraft
..............
Number
F
pr
A8OB1O
A20A40
A39A37
A37A31
B04A60
A18A24
A16A17
A33A32
A32A31
A18A19
A02AO1
A02A04
A04A07
A07A90
BO6A1O
A35A43
A44A43
B03A70
A48A47
B14B13
A98A81
B00A83
A74A73
A73A71
A71A69
A67A66
A66A63
B02A86
A99A82
B05AOO
A35B13
A34A33
B06A50
I
p
&
Number of Aircraft
Chapter 4
Conclusions
4.1
Introduction
In this chapter the major observations of the previous analyses are discussed and
final conclusions are drawn. These conclusions are divided into three sections; runways,
intersections and taxiways. Finally, the last part provides some directions for future
research.
121
4.2
Runways
The runway analysis showed some interesting results. The occupancy time on
landing does vary, as expected, with aircraft size but this variation is mainly due to the
fact that heavier aircraft tend to exit further down the runway, resulting in higher
occupancy times. However, aircraft using a given exit have similar occupancy time,
independently of aircraft size. The particular angle of the exit used also plays a very
significant role. Aircraft that use obtuse angled exits, usually exit at higher speeds, and
therefore maintain a higher average landing velocity resulting in similar occupancy times
compared to exits that are located much closer to the runway threshold. The standard
deviation of the occupancy time is usually smaller for aircraft using the first exits, than
those exiting further down the runway. Visibility also affected the occupancy time,
mainly due to the increased use of exits located further down the runway. In similar
weather conditions, aircraft using exit 6 (high speed) of runway 27, in day light had
average occupancy times of 35 seconds (lowest overall), while at night, in similar
weather conditions, most aircraft used exit 8 (low speed) and their occupancy times were
significantly increased (53 seconds).
In the analysis of exit usage, as mentioned above, heavier aircraft tend to use exits
located further away from the threshold, while smaller sized ones require shorter landing
distances and exit earlier. The specific turning angle of the exit was also a determinant
factor of its use. As a result, independently of runway, most aircraft tended to prefer the
use of obtuse angled (high speed) exits.
Exit velocities, as expected, were closely related to the angle of the exit, and
whenever aircraft where using obtuse angled exits they exited at significantly higher
speeds. However, this was only true, for high speed exits that were accompanied with
122
long exit segments and allowed the pilot enough distance to brake. The exit velocity did
not vary uniformly between aircraft classes and it seemed that exit velocity does not
depend on aircraft size.
The landing velocity profiles showed a close relationship between the amount of
deceleration and the type of exit (high or low speed) used after landing. In the final
approach, we observed a slight deceleration as the aircraft were approaching the
threshold. Data from runway 27, illustrated the importance of visibility, as in day light,
this deceleration was quite significant whereas during night operations we saw a much
smoother final approach profile. In runway 15R, under different weather conditions,
aircraft seem to even accelerate before the threshold.
4.3
Intersections
There is a significant difference in average crossing time depending in the runway
configuration and thus in the direction of use of some intersections. For example, when
intersections 10, 11, 12, 13 and 14 are used in the inbound direction (towards the terminal
area), usually after arrivals in runway 27, the crossing times seem to be much smaller
compared to those of departing aircraft which use the same intersections but in the
opposite direction (outbound), and often have to form a queue while waiting to depart
from runway 9 and thus cross these intersections very slowly.
Comparing the crossing times of the two different segments of each intersection
(time 1 and time 2), we observe that usually when an intersection is used in the inbound
direction time 2 is larger than time 1 and when it used in the outbound time 1 is larger.
This could be due to the fact that often pilots slow down and approach the terminal area
123
cautiously, while on their way to the departing runway, they accelerate faster out of an
intersection since the taxiways that lead away from the terminal are usually longer.
Aircraft size did not seem to be a determinant of crossing times as larger size aircraft had
longer crossing times only in few blocks. Exit usage was closely tied to the operating
runway configuration.
4.4
Taxiways
In the taxiway analysis we saw that there exists a close relationship between the
length of the taxiway and its velocity. Taxiways far away from the terminal almost
always exhibit higher average velocities since they tend to be less congested and free of
surrounding obstacles. We must note though, that in periods of heavy traffic the
differences in speed between longer and shorter taxiways become smaller. The use of the
inner and outer taxilanes under different configurations is almost identical. However, a
very strong relationship between the use of the supporting taxiways around the terminal
area, and the particular runway configuration seems to exist.
4.5
Directions for Future Research
Although after the analysis of the data many questions regarding the motion
characteristics of aircraft moving on the surface of Logan airport have been answered,
many more have been raised. More research should be done on the factors that affect
airport surface traffic in order to successfully develop and implement future surface
124
traffic automation systems. This study was limited to only Logan airport but a future one
should include and compare data from a wide variety of airports.
Such a study could include analysis of other variables that affect surface traffic
such as congestion and examine in further detail their potential effects. Most importantly,
a much larger size of data must be gathered. This requires some form of radar
surveillance at the airport. In our case, even though almost 12 hours of airport operation
data were made available for this study, after the breakdown of all aircraft by aircraft
type, runway and exit used we were left with very small sample for each variable that we
wanted to measure, limiting the accuracy of our results. There is much more data
available for Logan if further confidence in the measurements is required.
Hopefully, the content of this thesis will act a catalyst in attracting interest and
consequently, more studies will be under taken in the future, for a more complete
understanding of the surface traffic variables and a more efficient use of the airport
surface.
125
References
1.
Bussolari, Steven (1991), Real-Time Control Tower SimulationforEvaluation of
Airport Surface Traffic Automation, International Symposium on Aviation
Psychology Proceedings Vol. 1 (A92-4401)
2.
Harrison, Michael (1993), Airport Surface Traffic PlannerDesign Concept,
Systems Engineering and Development FAA, 19 April 1993.
3.
Lyon, Ervin F. (1991), Airport Surface Traffic Automation, The Lincoln
Laboratory Journal, Volume 4, Number 2, pp. 151-187.
4.
Marquis, Douglas (1991), A PreliminaryDescriptionof the Airport Surface
Traffic Automation (ASTA) System, ATC Project Memorandum No 41PMASTA-0006, Lincoln Laboratory, 9 January 1991.
5.
Mathaisel, Dennis F. (1994), A Simulation of Aircraft Motion on the Airport
Surface, MIT Flight Transportation Laboratory, 16 March 1994.
6.
Swedish, William (1972), Some Measures of Aircraft Performanceon the
Airport Surface, MIT FTL Report R72-4, May 1972.
7.
Weiss, W. E., Analysis of Runway Occupancy Time and SeparationData
Collected atLaguardia,Boston, and Newark Airports, MTR-84W228
MITRE.
8.
Flight Transportation Associates (1982), Airfield CapacityAnalysisfor BostonLogan InternationalAirport, for Massport, November 1982.
9.
Airborne Instruments Laboratory (1960), Runway Characteristicsof Jet
Transports in Routine Operation,Report No 5791-15, Federal Aviation
Agency, March 1960.
10.
Airborne Instruments Laboratory (1960), Use of Exit Taxiways at New York
International Airport, Supplement to Report No 7601-1, July 1960.
11.
Boston Logan InternationalAirport CapacityEnhancement Plan, Airports
Division FAA, October 1992
12.
A Report on Noise Abatement, Massachusetts Port Authority Noise Abatement
Office, January 1994.
126