Current Status of the Airport / Airline Industry Dr. Richard de Neufville Professor of Engineering Systems and Civil and Environmental Engineering Massachusetts Institute of Technology Airport Systems Planning & Design / RdN ©

Current Status of the Air Transport Industry y Objective: To define 4 current

situation and major new factors

y Airline and Airport Rankings y Major Trends • • • • •

Shrinking, Bankruptcy of Legacy Airlines Losses in Transfer Hubs: St Louis, Pittsburgh Rise of Innovative Carriers: Southwest, Fedex And Secondary A/Ps: Providence, Ft Lauderdale Demand for Low Cost Buildings at Airports Airport Systems Planning & Design / RdN ©

Major Recent Events y Disappearance of Major Airlines 4

TWA, Swissair, Sabena, Varig

y Mergers Japan Airlines and Japan Air Systems (2002) 4 Air France and KLM (2004) 4 America West and US Airways (2005) 4

y Major Bankruptcies 4

United, US Airways, Air Canada, Delta, Northwest

y Surge by Low-Cost, Chinese, Cargo Carriers Air Tran, Ryanair, easyjet, AirAsia 4 Cathay Pacific, China Airlines, EVA 4

Airport Systems Planning & Design / RdN ©

Electronic Ticketing y Big Savings – up to $3 billion for air transport industry 4 Less

staff, less space, less rent… 4 $1 per E ticket vs. ~$10 per paper ticket

y Status 4~

40 % of all tickets worldwide (Nov. 2005) 4 Over 80% in Canada 4 ~ 73% in UK, ~1/3 in Asia Pacific 4 Some airlines at 100%: Southwest, Ryanair Source: IATA WATS

Airport Systems Planning & Design / RdN ©

Principal drivers of air transportation industry y Long-term annual decrease in air fares: 4

Driving comparable annual worldwide traffic growth – aircraft size, engines, composite materials

y Low-cost carriers 4 4

Southwest, AirTran, Jet Blue, Westjet, Ryanair, easyjet, AirAsia New business practices

y Commercialization: 4

market economy management replaces… government ownership and economic regulation

y Globalization: 4

transnational airline alliances and airport groups

y Technical innovation: 4

e-commerce, RJs, satellite-based navigation Airport Systems Planning & Design / RdN ©

Annual Decrease in Air Fares

Relative cents/Revenue Pax-KM

Estimated Real Yields 110 100 90 80 70 60 1993

1997

2001

2005

Year

Source: IATA WATS Airport Systems Planning & Design / RdN ©

IATA Members’ Traffic, Revenues, Yield, and CPI Traffic

Revenues

Yield

Inflation

250

Percent of 1991

200

150

100

50

03

02

01

00

99

98

97

96

95

94

93

92

04 20

20

20

20

20

19

19

19

19

19

19

19

19

19

91

0

Source: IATA World Air Transport Statistics Airport Systems Planning & Design / RdN ©

World Traffic, (Pax-Km x 109) World and IATA Year Pax-km, Billions IATA Annual Growth % IATA World share, % IATA World 2005 3400 4001 85 10 7 2004 3082 3722 82.8 13 13.6 2003 2704 3236 83.5 (0.4) 1 2002 2770 3196 86 (1) (1) 2001 2652 2912 91 (4) (4) 2000 2757 3018 91 4 (2) 1999 2657 3074 86 6 6 1998 2514 2888 87 7 4 1990 1600 2186 73 18 8 1987 1042 1763 59 9 8 1982 712 1263 56 4 4 1977 600 1036 58 Source: IATA World Air Transport Statistics Note: Changed Series; now includes charter travel Airport Systems Planning & Design / RdN ©

Non-IATA Members y As of 2005, many airlines in the top 50 worldwide were not in IATA… 4 Southwest,

Jetblue, AirTran, Spirit, Continental Express 4 Westjet 4 Ryanair, easyjet 4 Frontier, Hawaiian, Skywest 4 Condor Airport Systems Planning & Design / RdN ©

Interpretation of Trends y Over past 13 years… 4 Yields

(revenues/unit distance) have dropped about 20% 4 While inflation has risen about 50% 4 So: costs on a constant basis cut in half 4 Thus: traffic doubled 4 Implying price elasticity about -1.3 > -1.0 4 So total revenues grow as price drops Airport Systems Planning & Design / RdN ©

Airports by millions of pax, 2005 (ACI + FAA data; US- Bold, hubs- italics) Airport Atlanta Chicago / OHare London / Heathrow Tokyo / Haneda Los Angeles / Internatl Dallas / Ft. Worth Paris / de Gaulle Frankfurt / Main Amsterdam / Schiphol Las Vegas Madrid Denver / International Phoenix Bangkok New York / Kennedy Houston / Bush Minneapolis / St. Paul Hong Kong / C L K Beijing / Pudong Detroit / Metro Orlando / International New York / Newark London / Gatwick San Francisco / Internatl Tokyo / Narita

2005 84.8 72.4 67.9 61.1 58.7 56.1 53.8 52.2 44.2 42.8 41.9 41.6 40.6 40.4 38.1 35.9

35.2 33.2 32.8 32.8 32.1

2004 83.6 75.4 67.3 62.3 60.7 59.4 50.9 51.1 42.5 41.4 38.5 42.4 39.5 38.0 37.4 36.5 36.8 36.7 34.9 35.2 31.1 31.8 31.5 33.5 31.1

Millions of Passengers 2003 2002 2001 78.8 76.6 75.9 69.4 66.5 66.8 63.2 63.0 60.7 63.2 61.1 58.7 55.0 56.2 61.0 53.2 52.8 55.2 47.9 48.1 48.0 48.1 48.1 48.6 39.8 40.6 39.5 36.3 35.0 35.2 35.4 33.7 34.0 37.5 35.7 36.1 37.4 35.6 35.5 29.1 30.5 30.6 31.7 28.9 29.4 34.1 34.4 34.8 33.2 32.6 35.2 26.4 33.5 32.6 24.4 27.2 24.2 32.7 32.4 32.3 27.3 26.7 28.2 29.6 29.0 30.5 29.9 29.5 31.2 28.8 30.7 34.6 23.5 25.8 25.4

2000 80.2 72.1 64.6 56.4 68.5 60.7 48.2 49.4 39.6 36.9 32.8 38.7 35.9 29.6 32.8 35.2 36.7 32.7 21.7 35.5 30.8 34.2 32.1 41.2 27.4

1993 47.8 65.1 47.6 41.5 47.8 49.7 25.7 31.9 20.1 22.5 17.3 32.6 23.5 17.1 26.8 20.3 23.4 24.4 * 24.2 21.5 25.8 20.1 32.0 20.0

Annual % 2000 - 05 1.1 0.1 1.0 1.7 -2.9 -1.5 2.3 1.1 2.3 3.2 5.5 1.5 2.6 NA 4.6 1.6 -0.4 NA NA -0.2 1.6 -0.8 0.4 -4.4 NA

Airport Systems Planning & Design / RdN ©

Airports by millions of pax, 2004 4 In

2005, airport traffic stagnated at most major airports

4 Big increases in • New Hubs – such as Madrid, Philadelphia • Secondary airports – London/Stansted • Asia, especially China, Thailand 4 Thus,

significant changes in ranking over last several years Airport Systems Planning & Design / RdN ©

Airports by millions of pax, 2005 (ACI + FAA data; US- Bold, hubs- italics) Philadelphia Singapore Miami / International Seattle / Tacoma Toronto / Pearson Rome / Fuimicino Sydney Munich Charlotte Barcelona Boston / Logan Jakarta Washington / Dulles New York / LaGuardia Seoul/Incheon Paris / Orly Mexico City Manchester (UK) Cincinnati Dubai Shanghai/Pudong Kuala Lumpur London/Stansted Miami/ Fort Lauderdale Washington/Baltimore St. Louis / Lambert Pittsburgh

30.8 30.7 30.2 28.7 28.6 28.6 28.0 27.1 26.4 26.1 26.0 24.9 22.7 22.5

22.0 21.5 19.7 13.7 10.4

28.5 30.4 30.2 28.7 28.7 28.1 28.1 26.8 24.7 24.5 26.1 25.7 22.7 24.4 24.2 24.0 23.0 21.5 22.0 21.7 21.1 21.1 20.9 21.0 20.7 * *

24.7 23.1 29.6 26.7 24.7 25.8 24.2 24.0 23.1 22.5 22.8 18.6 17.0 22.5 * 22.4 21.7 19.5 21.2 * * * 18.7 * 19.7 20.4 14.2

24.4 27.4 30.1 26.7 25.9 25.0 23.4 23.0 23.6 21.2 22.6 * 21.3 * 23.1 20.3 18.6 20.9 * * * * * 19.0 25.6 18.0

23.9 28.1 31.7 27.0 28.0 25.6 24.3 23.6 23.2 20.7 24.2 * 17.9 21.9 * 23.0 20.6 19.5 17.3 * * * * * * 26.7 19.9

24.9 28.6 33.6 28.4 28.8 25.9 23.5 23.1 23.1 19.8 27.4 * 20.0 25.2 * 25.4 20.7 22.5 * * * * * * 30.5 19.8

16.5 18.8 28.7 18.8 20.5 18.8 16.6 12.5 17.3 * 24.0 * * 19.8 * 25.3 * 12.8 12.3 * * * * * * 19.9 18.5

4.7 1.5 -2.0 0.2 NA 2.1 NA 4.8 4.2 7.4 -0.7 NA NA 0.6 NA -0.4 NA NA 0.0 NA NA NA NA NA NA -11.0 -8.8

Airport Systems Planning & Design / RdN ©

Changes in Transfer Hubs y Big changes in recent years y New Hubs Big: Paris/de Gaulle, Amsterdam, Madrid 4 Medium: Dubai; London/Stansted, Munich 4

y “Close” of old hubs Pittsburgh (US Airways shrunk to Philadelphia) 4 St Louis (TWA merged out of existence) 4 Zurich (collapse of Swissair) 4

Airport Systems Planning & Design / RdN ©

Current Major Airport Projects 4 Atlanta,

Toronto Airport Makeovers 4 Bangkok, Kobe Major New Airport 4 Osaka/Kansai; Tokyo/Haneda Runway landfills 4 Singapore Massive new Terminal 4 Shanghai/Pudong New Runway, Teminal 4 Paris/de Gaulle; DFW Pax Buildings, APM 4 London/HRW Terminal 5 ($8 billion) 4 Frankfurt A380 base (and T3?) 4 Madrid ; Miami/Intnatl Runway, Buildings 4 Doha (Qatar); Dubai Major Projects Airport Systems Planning & Design / RdN ©

Airline Rankings (Pax-Km, billions) Airline American United Delta Northwest Air France Lufthansa British Continental Southwest JAL Singapore Qantas Air Canada KLM Cathay Pacific USAirways China Southern Emirates ANA Air China Thai

2005 222 183 167 122 116 113 111 109 97 94 81 74 71 68 65 65 60 59 56 52 50

Source: IATA WATS

2004 209 184 158 118 107 109 106 101 87 95 77 74 66 63 57 65 54 * 55 * 51

2003 193 167 144 110 99 97 100 91 77 76 64 69 59 57 43 61 * * 52 * 45

2002 196 176 153 116 99 94 99 91 71 83 74 73 69 59 49 64 * * 54 * *

1995 165 180 137 101 50 62 94 57 * 70 48 52 * 44 * 61 * * 43 * *

1992 157 149 130 94 37 49 72 69 22 55 37 31 * 31 * 56 * * 38 * *

Annual % 02-05 4.4 1.3 3.1 1.7 5.7 6.7 4.0 6.6 12.2 4.4 3.2 0.5 1.0 5.1 10.9 0.5 NA NA 1.2 NA NA

Airport Systems Planning & Design / RdN ©

Airline Rankings (Passengers, millions) Airline American Southwest Delta United Northwest JAL Lufthansa ANA Air France China Southern Continental US Airways British Ryanair China Eastern Air China Iberia eastjet SAS Alitalia Air Canada Qantas America West KLM Korean Westjet

2005 98 88 86 67 58 51 49 48 48 43 43 42 36 33 30 28 27 26 25 24 24 23 22 22 21 9

2004 92 81 87 71 56 52 48 46 45 39 41 42 35 28 * 24 26 22 20 22 21 24 21 20 21 8

2003 89 66 84 67 53 34 44 43 44 * 38 41 35 23 * * 25 22 20 22 20 24 20 * 21 7

2002 94 64 90 69 54 34 44 44 43 21 40 47 34 21 * * 24 21 23 22 23 24 19 * 22 6

1995 80 * 87 79 49 29 33 38 * * 35 58 32 * * * * * 19 21 * * 17 * 22 *

1992 86 28 83 67 44 24 27 35 14 * 38 55 25 * * * * * 14 20 * * 15 * 20 *

Annual % 02-05 1.4 12.5 (1.5) (1.0) 2.5 16.7 3.8 3.0 3.9 34.9 2.5 (3.5) 2.0 19.0 NA NA 4.2 7.9 2.9 3.0 1.4 (1.4) 5.3 NA (1.5) 16.7

Airport Systems Planning & Design / RdN ©

Source: IATA WATS

Airline Rankings (Freight Tonne-Km, Billions) Airline Fedex UPS Korean Lufthansa Singapore Cathay Pacific China Airlines Air France EVA Cargolux Japan British KLM Emirates Northwest American Air China United Malaysian Asiana Nippon

2005 14.4 9.1 8.1 7.7 7.6 6.5 6.0 5.5 5.3 5.1 4.8 4.8 4.6 4.2 3.2 2.9 2.7 2.6 2.6 2.4 2.4

2004 14.6 7.4 8.3 8.0 7.1 5.9 5.6 5.4 5.5 4.7 4.9 4.8 4.5 3.5 3.3 2.9 2.6 2.6 * 2.7 2.4

2003 13.2 6.7 6.9 7.3 6.7 5.2 4.7 4.9 4.7 4.3 4.4 4.2 4.1 2.6 3.0 2.6 * 2.4 * 2.6 2.3

2002 13.0 6.6 6.0 7.2 6.8 4.8 4.5 4.9 4.1 4.2 4.4 4.1 4.0 * 3.0 2.6 * 2.8 * 2.6 2.2

1995 7.0 * 4.3 5.8 3.7 2.8 * 4.4 * * 3.8 3.3 3.6 * 2.8 2.4 * 2.5 * * 1.5

1992 5.8 * 2.7 4.3 2.9 1.7 * 3.3 * * 3.2 2.5 2.4 * 2.7 1.6 * 1.9 * * 1.1

% Change 02-05 3.6 12.6 11.7 2.3 3.9 11.8 11.1 4.1 9.8 7.1 3.0 5.7 5.0 NA 2.2 3.8 NA (2.4) NA (2.6) 3.0

Source: IATA World Air Transport Statistics

Asian Cargo airlines have surged over past three years

Airport Systems Planning & Design / RdN ©

Airline Rankings (Freight Tonne, millions) Airline Fedex UPS United Korean China Airlines Singapore Japan Airlines Lufthansa Cathay Emirates EVA China Eastern Air France China Southern Air China Northwest British EAT Asiana Cargolux ANA KLM Thai American Malaysian

2005 6.97 4.20 1.65 1.49 1.34 1.21 1.16 1.14 1.12 0.93 0.84 0.82 0.78 0.74 0.72 0.71 0.70 0.66 0.64 0.63 0.62 0.57 0.56 0.54 0.53

2004 7.00 4.02 1.61 1.52 1.74 1.13 1.19 1.15 0.97 0.79 0.86 0.68 0.77 0.67 0.65 0.75 0.71 0.60 0.69 0.57 0.61 0.56 0.54 0.54 0.55

2003 6.50 3.28 1.18 1.75 1.08 1.04 0.97 1.02 0.88 0.62 0.74 * 0.69 0.58 0.55 0.67 0.63 0.52 0.68 0.52 0.59 0.52 0.51 0.51 *

2002 6.41 3.21 1.03 1.26 1.00 1.03 0.92 1.03 0.85 * 0.62 * 0.68 * * 0.65 0.61 0.55 0.56 0.45 0.54 0.52 0.53 0.51 *

1995 3.40 * 0.53 0.85 * 0.59 0.84 0.98 0.52 * * * 0.66 * * 0.72 0.52 * * 0.43 0.46 0.55 0.38 0.64 *

1992 2.80 * 0.49 0.57 * 0.39 0.69 0.74 0.35 * * * 0.53 * * 0.48 0.39 * * * 0.38 0.37 0.24 0.51 *

Annual % 02 - 05 2.9 10.3 20.1 6.1 11.3 5.8 8.7 3.6 10.6 NA 11.8 NA 4.9 NA NA 3.1 4.9 6.7 4.8 13.3 4.9 3.2 1.9 2.0 NA

Source: IATA W orld Air Transport Statistics

Airport Systems Planning & Design / RdN ©

Main Freight Airports Airport Memphis Hong Kong Tokyo/Narita Anchorage Seoul/Incheon Los Angeles Internatl. Frankfurt/Main Singapore Miami Louisville Taipei New York/Kennedy Chicago/O'Hare Shanghai/Pudong Paris/de Gaulle Amsterdam London/Heathrow Dubai Bangkok Indianapolis New York/Newark Atlanta Dallas/Fort Worth San Francisco/Oakland San Francisco/Internatl Philadelphia Los Angeles/Ontario Cincinnati/Covington

Tons,Millions 3.6 3.1 2.4 2.6 2.1 1.9 1.8 1.8 1.8 1.8 1.7 1.7 1.5 1.6 1.6 1.5 1.4 1.2 1.1 0.99 0.95 0.77 0.74 0.59 0.59 0.55 0.52 0.25

Sources: ACI “Top 30 Airports” 2004 FAA CY 2005 Cargo Landings

Hubs in Blue.

Airport Systems Planning & Design / RdN ©

Airline Market “Caps” (=price/share x shares) US $/Share Airline Symbol Market Capitalization 2005 2001 Feb-03 Aug-04 Sep-05 Sep-06 US $, billions, Sep 06 UPS UPS 55 59 72 70 70 75.3 Fedex FDX 42 52 82 81 100 30.7 Southwest LUV 18 13 15 14 16 12.9 Singapore SPAAF.PK 6.6 6.9 8.8 11.5 est Ryan Air * RYAAY 25 39 30 46 57 8.8 British BAB 48 19 41 51 77 8.7 Lufthansa DLAKY.PK * 9 11.5 13 19.5 7.5 est GOL GOL * * * 32 34 6.6 Air France AF1.PA * * 16 17 19.7 5.0 est easyjet EJETF.PK 3 4 3 5.4 8.9 3.5 est Continental CAL 44 6 10 12 25 2.2 Jet Blue * JBLU 6 13 10 10 1.7 American AMR 32 3 9 12 10 1.7 Alaska ALK 33 19 22 31 37 1.5 Virgin Blue VBA.AX 1.6 1.6 1.4 est AirTran AAI 12 11 9 0.9 JAL JALSY.PK 6 11 14 14 10 0.7 est Westjet * WJA.TO 18 11 13 11 10 0.4 est Airasia AIABF.pk 0.3 est Hawaiian HA 3 2 7.8 3 4 0.2 ~0 Alitalia AZA.MI 0.9 Delta DALRQ.pk 38 9 4 0.7 0.7 0.15 USAirways UAIRQ.OB 13 0.2 2 0.16 0.3 0.1 Northwest NWACq.pk 21 6 10 0.5 0.8 0.05 Air Canada Ace-rv.TO 6 3 0.07 0 0.06 0 United 33 1 0 0 Sources: Yahoo Finance and Google *Adjusted for Stock Split

Airport Systems Planning & Design / RdN ©

Airport Market “Caps” (=price/share x shares) Share Price, Local Money 2001 2002 2003 2004 2005 BAA (UK) 6.13 6.2 5.1 5.5 5.95 Fraport * 25.6 19.6 23 31 Copenhagen 770 589 460 885 1312 AIAL (New Z.) 3.46 4.54 5.27 6.75 1.9 Beijing 2.03 1.82 1.65 2.33 2.9 Vienna 39.1 34.6 31.5 43.8 50.3 ASUR (Mexico) 18.1 13.4 13.9 18.4 32.9 Zurich 201 124 34 101 174 Malaysia 1.54 2.15 1.46 1.41 1.7 Florence * * 15.8 9.8 31.1 Source: Jane's Airport World, Summer issues and market quotes Airport

2006 9.32 60 240 2.0 5.3 63.3 39.1 NA NA NA

US$, Billions 2006 (or 2005) 18.98 6.99 0.35 1.82 2.58 1.71 1.18 0.71 0.49 0.12

Many airports are economically more powerful than airlines!

Airport Systems Planning & Design / RdN ©

Airline Alliances Star Alliance -- United, Lufthansa, Air Canada, Thai, US Airways, ANA, Singapore, LOT, SAS, Air New Zealand, Swiss, TAP, Bmi, Varig, South African, Asiana, Austrian, Spanair

oneworld

American, British, Aer Lingus, Finnair, Iberia, Qantas, Cathay Pacific, Lan Chile

SkyTeam

Air France + KLM, Alitalia, Czech, Korean, Continental, Delta, Northwest, Aeromexico, Aeroflot

Airport Systems Planning & Design / RdN ©

Alliances’ Market Shares 2004 Market Share of Systems

Alliance

Pax-km % millions of world Star 752 25 Skyteam 642 21 oneworld 530 18 Alliances 1924 64 Total 2989 Source: !ATA World Air Stats. Airport Systems Planning & Design / RdN ©

New Types of Airlines y Cargo Integrators 4 UPS,

Fedex, DHL 4 Role of “Post Offices” ??

y Low-Cost Carriers 4 Point-to-point:

Southwest, Jetblue, Ryanair 4 “Network”: Easyjet, AirTran 4 Quasi-Network: Southwest??

y The innovators are the most profitable and valuable airlines Airport Systems Planning & Design / RdN ©

Challenge to Traditional Network Carriers y Is their business model working? 4 Will

people pay enough for convenience of

• easy connection at hubs • big expensive passenger buildings • travel agents

y If not, what will they do? 4 Squeeze

out costs (wages, standards) and survive on a more modest scale? 4 Manage by having “cheap” partners • Delta -- Song; United -- Ted… (hasn’t worked) 4 Or

disappear? TWA, Sabena, Swissair… Airport Systems Planning & Design / RdN ©

Airline Seat-Mile Costs, 06 Q1

Ai rw on ays tin e N nta or l th w es t D el ta U ni te d Al as Am ka Am er er ica ica n W es t Fr on tie Ai r rT ra n Sp So iri t ut hw es Je t tB lu e C

U

S

Cemts per Sea-Mile

20.0 18.0 16.0 14.0 12.0 10.0 8.0 6.0 4.0 2.0 0.0

Source: US DOT, BTS, www.bts.gov/press_releases/ 2006 Airport Systems Planning & Design / RdN ©

Airline Seat-Mile Costs, 05

Cents

18.0 16.0 14.0 12.0 10.0 8.0 6.0

Legacy

Source: US DOT, BTS, www.bts.gov/press_releases/ 2005

JetBlue

ATA

Southwest

Spirit

America West

Air Tran

Frontier

Continental

Alaska

Northwest

United

American

Delta

US Airways

4.0 2.0 0.0

LCC Airline Airport Systems Planning & Design / RdN ©

Effect of Low-Cost Carriers y Market Share becoming dominant 4 US:

About 45% 4 Europe: 12% + 20% charters = 1/3 of total 4 Inter-Asia: only 6% as of summer 2004

y Real Yields have dropped by 1/3 in past decade Source: IATA WATS and McKinsey and Co. Airport Systems Planning & Design / RdN ©

Consequences for Traffic y Cheaper travel will increase traffic y Where will it go? 4 To

traditional hubs of legacy majors? 4 To/from leisure locations and homes? • Yucatan, Malaga, Bali, etc 4 To

secondary airports?

• Miami/Ft. Lauderdale, Los Angeles/Ontario, London/Stansted, Frankfurt/Hahn, Rome/Ciampino, etc.

y Airport customers likely to demand new locations, cheaper facilities Airport Systems Planning & Design / RdN ©

Consequences for Airports (1) y “Low cost airlines” are causing the development of “low cost airports” 4 Secondary

airports: Boston/Providence, Miami/Fort Lauderdale, London/Luton 4 Inexpensive terminals, designed for new ways of handling passengers – such as Jetblue facility at New York/Kennedy • (see discussion by Regine Weston) • Compare Boston Delta and Jetblue facilities Airport Systems Planning & Design / RdN ©

Consequences for Airports (2) y Struggle of “low cost” and “legacy” airlines extending to competition between “low cost” and traditional main airports 4 Boston/Providence

vs. Boston/Logan 4 Miami/International vs Miami/Ft Lauderdale 4 London/Heathrow vs. London/Stansted

Airport Systems Planning & Design / RdN ©

Bottom Line ... y The nature of the Airport Business is changing dramatically y Not clear that airport professionals fully recognize full implications y Strong professional tensions … 4 Some

examples (not for publication) Airport Systems Planning & Design / RdN ©