Air Travel at the Edge of Chaos
George L. Donohue, Ph.D.
Professor Systems Engineering and Operations Research
Director of the Center for Air Transportation Systems Research
Volgenau School of Information Technology and Engineering
NEXTOR Workshop 28 Sept, 2007
CENTER FOR AIR TRANSPORTATION SYSTEMS RESEARCH
© George L. Donohue 2007
Outline
• How bad and widespread is the Problem
• Passenger QOS
• Economic Impact
• What are the Underlying Causes
• Too Many Scheduled Flights into Too Few Runways
• Why the Airlines cannot fix the Problem Themselves
• Prisoners Dilemma and Curse of the Commons
• Government (Congress/DOT/FAA) Measures Required
to Fix the Problem
• Airport Arrival Time Slot Auctions
• NEXTGEN ATM system
• Larger Aircraft Fleet Implications for the Environment
2
CATSR
Air Transportation System (ATS) is a CAS
Network with 6 Interacting Layers
•The ATS is a Public - Private Partnership with
conflicting objective functions:
•Public – Commerce and safety; interest groups
•Private – Profit maximization
Passenger/Cargo Layer (Delays, Cancellations)
Airline Layer (Routes, Schedules, A/C size)
TSA/FAA Layer (ATC Radar, Radios, Ctr’s, Unions)
Weather Layer (Thunderstorms, Ice Storms)
Physical Layer (i.e. Cities, Airports, Demographics)
Government Regulatory Control Layer
3
CATSR
Background: Air Transportation System
Passenger Tier Performance = f (Vehicle Tier Performance, Passenger
Factors)
4
CATSR
Passenger Total Delay – Airports
• 29% of the OEP-35 airports  50% Total EPTD
• some airports significantly impact EPTD more than others (e.g.
ORD, ATL, DFW and MCO)
50%
Close Network of OEP35 Airport in 2004
5
CATSR
200 Routes generate 50% of Total EPTD
• 17% of the 1044 routes between OEP-35 airports  50% Total EPTD
• LGA, JFK, EWR, PHL connected Routes  11 out of top 20 routes
50%
Close Network of OEP35 Airport in 2004
6
CATSR
Top 20 Worst Airports in the US:
Passenger Quality of Service Metric
Year
Rank
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
7
2004
Airports
ORD
EWR
LGA
PHL
ATL
MIA
FLL
MCO
DFW
LAS
BOS
SFO
IAD
JFK
CLE
SEA
TPA
STL
PDX
BWI
Prob. Of
PaxDelay
>45 min
14%
14%
13%
12%
11%
9%
9%
9%
9%
9%
9%
9%
9%
9%
9%
8%
8%
8%
8%
8%
2005
Prob. Of
PaxDelay
Airports >45 min
18%
EWR
17%
LGA
14%
ATL
13%
PHL
13%
BOS
12%
ORD
12%
FLL
12%
JFK
11%
MIA
11%
SFO
10%
SEA
10%
IAD
10%
TPA
10%
MCO
9%
BWI
9%
PIT
9%
PDX
9%
DTW
9%
LAS
9%
DCA
2006
Airports
ORD
EWR
LGA
PHL
JFK
IAD
MIA
ATL
MDW
DTW
DFW
BOS
DEN
CLT
IAH
CLE
PIT
DCA
MEM
SFO
Prob. Of
PaxDelay
>45 min
17%
16%
15%
15%
14%
12%
12%
12%
12%
12%
12%
11%
11%
10%
10%
10%
10%
10%
10%
10%
CATSR
Average of 2004 to 2006
Airports
EWR
LGA
ORD
PHL
ATL
JFK
BOS
MIA
FLL
IAD
DFW
SFO
DTW
MCO
LAS
CLE
PIT
SEA
MDW
DCA
Prob. Of
PaxDelay >45
min
16%
15%
15%
13%
12%
11%
11%
11%
10%
10%
10%
10%
9%
9%
9%
9%
9%
9%
9%
9%
D. Wang, GMU PhD. In Progress
Many Highly Congested Airports can Shift
Passengers to other Large Airports
Connecting
Airport
Passengers
%
Chicago O'Hare
59
Newark NJ
32
NY LaGuardia
8
NY JFK
40
Philadelphia
38
Atlanta
66
Boston
15
Miami
55
Washington Dulles
53
Dallas/Fort Worth
60
8
FAA 2006 NPIAS
CATSR
Airline Load Factors are Increasing
Percent Aircraft Seats Occupied (Average)
90
Load Factor
(Anticipated)
85
80
Load Factor ATA
Historical Data
75
70
65
60
55
50
45
1960
1970
1980
1990
Year
9
2000
2010
CATSR
GMU Model Projects Passenger Delays to Greatly
Exceed 2000 delays by 2010
Total Passenger Delays
160
Delayed Flights
Cancelled Flights
Poly. (Delayed Flights)
Poly. (Cancelled Flights)
Hours (millions)
140
120
100
80
60
40
20
1998
2000
2002
2004
2006
2008
2010
2012
Year
10
D. Wang 2007
CATSR
Annual Passenger Enplanements Predicted to be
Lost: FAA Forecast to 2025
CATSR
Annual Projected Enplanements Foregone
Because of Airport Capacity Constraints
25
ORD
20
JFK
2025
2015
15
2005
EWR
10
LGA
Airports
STL
TPA
SLC
SEA
SFO
PIT
SAN
PHL
PHX
PDX
ORD
MIA
MSP
MEM
MCO
MDW
LAX
LGA
LAS
IAH
JFK
IAD
FLL
HNL
DTW
EWR
DEN
DFW
DCA
CLT
CVG
BWI
CLE
ATL
5
0
11
Optimistic: All
Planned Airport
Improvements
Occur
All available landing slots fully
utilized regardless of congestion
BOS
Annual Enplanements Lost (Millions)
30
FAA 2005 TAF & 2004 Benchmark
Estimated Annual Cost to US (Lost Consumer Surplus,
2005$) due to Expected Airport Capacity Limitations
Annual Cost to US Economy ($B)
$25
$20
$15
$10
--FAA Assumptions on
Growth in Airport
Operations
--Boeing Passenger
Growth Assumptions:
3.6% per year
--Aircraft Upgage: 5% in
2015, 10% in 2025
CY2015, All A/P
Improvements
CY2015, No A/P
Improvements
Assumes:
$200/segment ticket
Price Elasticity = -1
CY2025, All A/P
Improvements
$5
CY2025, No A/P
Improvements
$0
100%
12
95%
90%
85%
Usable NAS Capacity (%)
80%
Shaver 2007
CATSR
Minimum Congestion Cost is a function of NEXTGEN
Technology Effectiveness and Network Efficiency
Annual Congestion Cost ($B)
$20
Caution: Some Costs Not Included
Sum of Costs ($B)
$15
Costs Resulting from Passenger
Delays and Flight Cancellations
$10
$5
Consumer Surplus Costs Resulting
From Limiting Airport Slots
$0
0.8
0.85
0.9
Congestion Factor
13
0.95
1
CATSR
Outline
• How bad and widespread is the Problem
• Passenger QOS
• Economic Impact
• What are the Underlying Causes
• Too Many Scheduled Flights into Too Few Runways
• Why the Airlines cannot fix the Problem Themselves
• Prisoners Dilemma and Curse of the Commons
• Government (Congress/DOT/FAA) Measures Required
to Fix the Problem
• Airport Arrival Time Slot Auctions
• NEXTGEN ATM system
Larger Aircraft Fleet Implications for the Environment
14
CATSR
Severe Congestion at NY Area Airports:
A 40-year-old Reality
CATSR
Timeline recap of congestion management measures
HDR at EWR, LGA, JFK,
DCA, ORD
Perimeter rule at LGA,
DCA
1969
- Limited #IFR slots
during specific time
periods
- Negotiation-based
allocation
15
early 1970s
Deregulation
1978
Removal of HDR
at EWR
Introduction of Huband-Spoke Network
System
Slot
ownership
AIR-21
1985
4.2000
Use-it-orlose-it rule
based on
80% usage
Exempt from
HDR at LGA,
JFK, ORD
certain flights
to address
competition
and small
market access
NYNJ comparison to Comparable
European Airports
Airport
Frankfurt, Gr (FRA)
London, UK (LHR)
Newark (EWR)
Amsterdam, NL (AMS)
New York Laguardia (LGA)
Munich (MUC)
New York Kennedy (JFK)
Madrid, Sp (MAD)
Total
Movements
2005
490,147
477,884
437,402
420,736
404,853
398,838
<353,000
415,677
Data taken from ACI-NA,
EC PR2006 and FAA ASPM
16
2000
458,731
466,815
450,187
432,480
384,554
<384,000
<384,000
Total
Passengers
2005
52,219,412
67,915,403
33,999,990
44,163,098
<29,000,000
<29,000,000
41,885,104
41,940,059
2000
49,360,630
64,606,826
34,188,468
39,606,925
<28,000,000
32,856,220
32,893,190
CATSR
Average Delays
Minutes
2006
2.7
3
28.8
0.7
23.4
1.8
24.3
1.8
EWR a NYNJ Airport with No Slot Controls:
Delays 2006
Delay per Flight (minutes)
EWR
80
60
40
20
35 Airport BN Model
0
Summer 2006 Data
-20
-40
(N. Xie GMU 2007)
0
5
10
15
Time of Day (hour)
Passenger Quality of
Service Metric that
Includes Flight
Cancellations & Missed
Connections
(D. Wang GMU 2007)
17
20
CATSR
Calculated Capacity (Today) and Actual Throughput
Optimum Rate
CATSR
80
Calculated Capacity - Today
Facility Reported Rate - EWR
(arrivals, departures per hr)
Arrivals per Hour
42, 42
60
EWR :
DoT/FAA
40
Infrequent
2004 Capacity
Benchmark Report
Most Frequent
20
Each symbol represents actual
traffic during a single hour
0
0
20
40
60
80
Departures per Hour
Marginal Rate
IFR Rate
80
60
Arrivals per Hour
Arrivals per Hour
80
40, 40
40
20
33, 33
40
20
0
0
0
18
60
20
40
60
Departures per Hour
80
0
20
40
60
Departures per Hour
80
EWR Free-Market Fleet Mix Appears to be
Far from Optimum
19
CATSR
New York LaGuardia Airport:
Case Study of a Slot Controlled Airport
Data (2005):
• Throughput:
•
•
•
•
20
404,853 flights/yr
Average flight delay:
38 min
Revenue passengers:
26,671,787
Average aircraft size:
96 passenger
Average inter-city fare:
$133
CATSR
NYNJ Airport with Current Slot Controls:
LGA 2004 – 2006 (DOT Data)
CATSR
Calculated Capacity (Today) and Actual Throughput
LGA
60
Calculated Capacity - Today
60
39,39
40
Arrivals per Hour
Delay per Flight (minutes)
Optimum Rate
80
20
0
Facility Reported Rate - LGA
(arrivals, departures per hr)
40
Infrequent
20
-20
-40
Most Frequent
Each symbol represents actual traffic
during a single hour
0
0
5
10
15
20
0
Time of Day (hour)
20
40
60
Departures per Hour
Marginal Rate
IFR Rate
60
60
37,37
Arrivals per Hour
Arrivals per Hour
37,37
40
20
0
21
40
20
0
0
20
40
Departures per Hour
60
0
20
40
Departures per Hour
60
Current Government Rules at LGA
Lead to Poor Use of Runway Resources
• Inefficient use of
resources
CATSR
Airports win
Airlines win
(High Load
Factor/Large
Aircraft)
Airports lose
Airlines lose
(Low load
factor/Small
Aircraft)
22
LGA High Frequency Flights:
Current and 90% of Optimum
Boston Logan
Washington DC Reagen Nat
Chicago O'Hare
Atlanta Hartsfield
Fort Lauderdale Fl
Raueigh/Durham NC
Detroit Mi
Charlotte NC
Columbus OH
Dallas Ft Worth
23
Market Daily
Freq
BOS
73
DCA
69
ORD
62
ATL
48
FLL
43
RDU
37
DTW
32
CLT
32
CMH
26
DFW
26
A/C
seats
106
108
138
156
157
46
122
102
46
148
Model Model Normalized
Freq
seats
Freq
60
208
0.8
68
131
1.0
56
139
0.9
32
145
0.7
26
181
0.6
22
95
0.6
22
175
0.7
30
97
0.9
22
102
0.8
26
146
1.0
CATSR
Rank
Seats
2.0
1.2
1.0
0.9
1.2
2.1
1.4
1.0
2.2
1.0
1
2
3
4
5
6
7
8
9
10
Outline
• How bad and widespread is the Problem
• Passenger QOS
• Economic Impact
• What are the Underlying Causes
• Too Many Scheduled Flights into Too Few Runways
• Why the Airlines cannot fix the Problem Themselves
• Prisoners Dilemma and Curse of the Commons
• Government (Congress/DOT/FAA) Measures Required
to Fix the Problem
• Airport Arrival Time Slot Auctions
• NEXTGEN ATM system
• Larger Aircraft Fleet Implications for the Environment
24
CATSR
Why do the Airlines Schedule beyond the Maximum Safe
RW Capacity with Flights that Loose Revenue?
CATSR
• There is no government regulation to limit schedules for
safety or compensate passengers for delays and
cancellations
• These were errors in the 1978 Deregulation Act
• Passenger surveys indicate that frequency and price are
the most desirable characteristics of a flight
• Passengers are not told of consequences of schedule to
travel predictability
• If any one airline decided to offer rational schedules, their
competition will offer more frequency to capture market
share
• Thus, still producing delays and cancellations for all
• In Game Theory, this is called the Prisoner’s Dilemma
25
A Natural Question? Is There an Optimal
Allocation of Scarce Runway Resources?
• What would happen if schedules at major airports were
capped by predictable runway capacity and allocated by a
market mechanism?
• What markets would be served?
• How would airline schedules change?
– Frequency
– Equipment (#seats per aircraft)
• How would passenger demand change?
– At airport
– On routes
• How would airfares change?
– What would happen to airline profit margins?
• How would airport and network delays be altered?
26
CATSR
Outline
• How bad and widespread is the Problem
• Passenger QOS
• Economic Impact
• What are the Underlying Causes
• Too Many Scheduled Flights into Too Few Runways
• Why the Airlines cannot fix the Problem Themselves
• Prisoners Dilemma and Curse of the Commons
• Government (Congress/DOT/FAA) Measures Required
to Fix the Problem
• Airport Arrival Time Slot Auctions
• NEXTGEN ATM system
Larger Aircraft Fleet Implications for the Environment
27
CATSR
Modeling Approach and Assumptions
• Port Authority of NY&NJ has the ability to
Determine and Set an Optimum Schedule to:
• Operate at Competitive Profit Margins
• Maximize Passenger Throughput
• Ensure an Airline Operating Profit (Max, 90%,80%)
• All Current Origin and Destination Markets are
Considered
• 67 Scheduled Daily Serviced Markets
• Current Market Price Elasticity Remains
Constant
28
CATSR
NY LGA Has 67 Daily Markets
29
CATSR
Airline Competitive Scheduling:
Modeling Framework
Auction 32
Slots/Hr
Demand-Price Elasticity
$
ASPM, BTS
databases
S1
S2
D
#
Network Flow
Optimization Problem
Flight schedules
Fleet mix
Average fare
Flight delays
Delay Network
Simulation
30
(Le, 2006)
CATSR
Model Estimate of Aircraft Gauge Change
Estimate of Aircraft Up-Gauging
300
Current Fleet Allocation - 1010 Flts
90% Optimum Fleet Allocation - 806 Flts
Number of Daily Flights
250
200
150
100
50
0
19 to 37 44 to 50 69 to 77
31
88 to
110
117 to
133
138 to
158
Aircraft Seating Capacity
166 to
181
194 to
225
CATSR
Unprofitable daily markets at LGA
CATSR
• Three markets (13 Flights) that are not
profitable to operate on a daily basis are
identified to be:
•
•
•
Lebanon-Hanover, NH (LEB),
Roanoke Municipal, VA (ROA),
Knoxville, TN (TYS).
Runway Cap. Market seats/AC Fare Passengers RPM Yield Flights/day
unconstrained LEB
19
$153
50
$0.72
6
10,9,8,7
ROA
37
$186
77
$0.46
5
6,5,4
TYS
50
$125
85
$0.19
2
32
Research Results – Win Win
CATSR
Airlines adapt with aircraft size and frequency to congestion
constraint:
Positive impacts on passengers, airports, airlines, and ATC
•Airlines
• Reduced frequency with
larger aircraft
• Most Markets Retained
• More Profitable (90% of
Optimum)
•Passengers
33
• Markets served: Little
change
• Airfares no change
• Improved Predictability
• Airports
• Increased passenger
throughput
• Reduced delays (70%)
•Air Traffic Control
• Reduced delays
– Demand within capacity
– Reduced Prob. SRO
Outline
• How bad and widespread is the Problem
• Passenger QOS
• Economic Impact
• What are the Underlying Causes
• Too Many Scheduled Flights into Too Few Runways
• Why the Airlines cannot fix the Problem Themselves
• Prisoners Dilemma and Curse of the Commons
• Government (Congress/DOT/FAA) Measures Required
to Fix the Problem
• Airport Arrival Time Slot Auctions
• NEXTGEN ATM system
• Larger Aircraft Fleet Implications for the Environment
34
CATSR
The Predicted Growth in Aviation Demand is based on
Passenger Demand NOT Aircraft Operations
CATSR
• Larger Aircraft will be required to meet X2 or X3 demand
• Business Jet and VLJ Air Taxi Service will emerge to
compete with Commercial aviation due to current System
Failure
• May not be able to put the Geni back in the Bottle
• Environmental Implications?
• New Aircraft (e.g. B 787) should be Environmentally
Friendly (Emissions/passenger/mi.?)
• US airlines are not currently ordering them due to poor financial
position
• New Public Policy will be needed to Deal with these
Complex Adaptive System Problems
• NEXTGEN System not addressing these issues
35
Center for Air Transportation System Research
Publications and Information
• http://catsr.ite.gmu.edu
– Other Useful Web Sites
• http://mytravelrights.com
• http://gao.gov
• http://www.airconsumer.ost.dot.gov
36
CATSR
CATSR
BACKUP Material
37
Summary of European Passenger Bill of Rights http://news.bbc.co.uk/1/hi/business/4267095.stm
CATSR
• Overbooked Flights
•
•
Passengers can now get roughly double the existing compensation if they are bumped off a
flight.
– Compensation must be paid immediately.
– These passengers must also be offered the choice of a refund, a flight back to their
original point of departure, or an alternative flight to continue their journey.
May also have rights to meals, refreshments, hotel accommodation if necessary even free emails, faxes or telephone calls.
• Cancelled Flights
•
•
•
•
•
Offered a refund of your ticket, along with a free flight back to your initial point of
departure, when relevant. Or, alternative transport to your final destination.
Rights to meals, refreshments, hotel accommodation if necessary, even free e-mails or
telephone calls.
– Airlines can only offer you a refund in the form of travel vouchers if you agree in
writing
Refunds may also be paid in cash, by bank transfer or cheque
If the reason for your flight's cancellation is "within the airline's control", it must pay
compensation.
Compensation for cancellations must be paid within seven days.
• Delayed Flights
•
38
•
Airline may be obliged to supply meals and refreshments, along with accommodation if an
overnight stay is required.
If the delay is for five hours or more, passengers are also entitled to a refund of their ticket
with a free flight back to your initial point of departure if this is relevant.
Air Transportation is Characterized as a
Complex Adaptive System (CAS)
Fleet
Attributes
Fleet
Costs
Trips flown
by fleet
CATSR
Fleet
Revenue
Effect on
GDP
Passenger
Delays
Delays
Airport
Capacity
Enroute
Capacity
Flight Delays
&
Cancellations Offered
Schedule
Inconven
ience
Reference
demand
39
Airline
Profits
Effective
Price
Flights by
Fleet
Market
Clearing
Ticket
price
Aircraft
Fleets
Active
fleet
Effective
price by
length of trip
Baseline
Demand
Bengi Mezhepoglu, PhD
in progress