Airport and Cargo
Hanzhang Guo
February 2023
1
Introduction
An airport is an airdrome with extended facilities, mostly for commercial air
transport
An airdrome is a location from which aircraft flight operations take place, regardless of whether they involve air cargo, passengers, or neither, and regardless
of whether it is for public or private use. Aerodromes include small general aviation airfields, large commercial airports, and military air bases
1.1
operations in an airport
• Gate assignment
• Aircraft taxiing
• Departure/arrival scheduling
• Cargo Handling
1.2
Airport identifiers
International Air Transport Association (IATA)
cell4
cell7
1.3
International Civil Aviation Organization (ICAO)
cell5
cell8
Revenue Passenger Kilometer (RPK)
RPK is product of number of transported passengers (who generate revenue)
and distance flown.
1.4
Relevance of airports
• airports are transport interchanges (multimodality) and allow global transportation for people or goods
• airports create employment
1
• airports act as business gateways - global companies and business
• airports are main driver for tourism growth
• airports are economic engines that generate economic development on
their own
1.5
Types of airports (important)
• airfields (general aviation, sporadic traffic)
• OD airports (mostly origins or destinations of passenger flows)
• hubs (mostly transfer points)
2
Landside
2.1
What is landside
Landside: subject to fewer special laws and is part of the public realm, while
access to the airside zone is tightly controlled. Landside facilities may include
publicly accessible airport check-in desks, shops and ground transportation facilities
2.2
Landside of an airport
• The terminal is the actual interface between landside and airside
• Landside access interface: curbside, parking, public transport, airport city
• Processing system: passenger and baggage flows (arrivals, departures, transfer)
• Airside access interface: apron, gates
2.3
Requirements for a terminal building
Requirements for a passenger building stem from different sources, mostly due
to expected traffic in the airport
• airline types
• passenger types
• route network
• aircraft sizes and mix
• peak behaviour (number of waves, popular arrival/departure slots
These are intertwined aspects that determine the type of airport and, hence,
the type of terminal(s) required
2
2.4
Types of airport
• international Hub airport
• international airport
• regional airport
2.5
Types of airlines
• flag-carriers - often hub traffic, many destinations, heterogeneous fleet,
price and service diversification.
• charter carriers - seasonal schedule (mostly point-to-point), holiday destinations.
• low-cost carriers - point-to-point short-haul homogeneous fleet, no price
and service diversification.
2.6
Types of passengers
• domestic/international
• arriving/departing/transfer
• leisure/business
2.7
Terminal configurations (important)
• linear piers
• finger piers
• satellites
• midfield (linear or X-shaped)
• transporter
2.7.1
linear piers
advantage: short walking distance for OD passengers, efficient aircraft taxiing
disadvantage: long walking distance for transfer pax, decentralized concept
(more staff and facilities needed)
2.7.2
finger piers
advantage: more centralized facilities, increased attractiveness and profitability of retail opportunities.
disadvantage: long walking distance for transfer pax.
3
2.7.3
satellite
advantage: if connection is below ground, aircraft can move freely around
satellites.
disadvantage: more complicated logistics.
2.7.4
midfield concourses (linear)
advantage: allows for (almost) single-airline operations (e.g., UA in DEN).
Efficient taxiing and parking
disadvantage: more complicated logistics. Need for underground Automated
People Mover
2.7.5
midfield concourses (X-shaped)
Counter-intuitively, the average walking distance for passengers is higher w.r.t.
linear concourses. In addition, issues with stands at the corners and aircraft
maneuvering
2.7.6
transporter
advantage: limit construction costs, free aircraft from docking operations
disadvantage: transporters are expensive, require highly trained people, increase the turnaround time by 10/15 minutes, passengers face weather and
increased discomfort
2.8
Terminal configurations
• walking distance: geometrical measures might be doomed to fail
• aircraft taxiing around buildings: entails substantial costs and might affect
competitiveness of an airport
• transporter economics: are they a cost-effective complement to terminals?
• flexibility: easiness to adapt to different types of traffic
3
Airside
Airside: portion of an airport between the boarding gates and the airspace.
Major elements of the airside are runways, taxiways, aprons, ramps, and navigational systems.
Might take up to 90% of the total land occupied by an airport. Highly dependent on number and direction of runways, geometric configuration of runways
(and taxiways), dimensional standards for which the airport is designed.
4
3.1
3.1.1
Airside of an airport
Design questions
• How much land to acquire or reserve?
• What should be the overall geometric layout of runways, taxiways and
aprons?
• What size of aircraft should the airport be designed for?
• How should the construction of airside facilities be phased?
3.1.2
Potenrial mistake
• No flexibility allowed for future developments
• overbuilding during the initial stages
• Adopting a hierarchical, non-integrated design approach that fails to consider interactions
• No thorough analysis of the economic implications of the design choices
3.2
Airport layout factors
• number, layout, geometry of the runways. Features such as runway length,
separation between parallel runways, angle between non-parallel runways,
ARCs selected are also crucial
• location of landside facilities relative to airside facilities
• additional reserve land area considered for future expansion
3.2.1
Region difference
• Asian: Most of the traffic is intercontinental
• North America: Most of the traffic is domestic, or feeder to large aircraft
• Europe is in between
3.3
Wind coverage
Takeoffs and landing operations should occur into the wind and with limited
crosswind
• 19 km/h for airplanes whose reference field is 1, 200 m,
• 24 km/h for airplanes whose reference field is in the range (1, 200, 1, 499]
m
• 37 km/h for airplanes whose reference field is 1, 500 m,
5
3.4
3.4.1
Runway systems
single runway
Many major (non-hub) and secondary airports have only a single runway. In
many cases, this is due to space restrictions. Their geometric layout is generally
quite simple
In single-runway airports, length of the runway is key to determine traffic
3.4.2
parallel runways
With two parallel runways (quite common configuration), the separation between runway is paramount to define the allowed volume of traffic
• close runways: centerline separation is less than 762 m (760 m according
to ICAO). Movements occurring on the 2 runways must be coordinated
Arrival dependent, Departure dependent
Not allow building in between
• independents runways: centerline separation is more than 1, 310 m.
Movements across runways are independent
Arrival independent, Departure independent
Allow building in between
• medium-spaced runways: centerline separation is in between the previous values. Independent departures are allowed, as well as “segregated”
operations (one runway for departures, one for arrivals). Arrivals are not
independent instead
Arrival dependent, Departure independent
Not allow building in between
3.4.3
independent runways
advantage:
• Efficient utilization of area between runways
• Proximity of passengers to all runways
• Good airfield traffic circulation
disadvantages:
• Ground connections to/from city requiring taxiway bridges
• Further expansion of landside building(s) hindered by runway system itself
6
3.4.4
staggered runways
advantages:
• additional vertical separation for pair of landing aircraft
• reduced taxiing distance when one runway is for departures and the other
ones for arrivals
disadvantage: more space required.
3.5
Runway design of length
• weight of aircraft and settings of lift- or drag-increasing devices → more
weight requires longer runway
• stage length to be flown → longer route requires more fuel, hence
more weight, hence → see above
• weather (temperature and surface wind) → stronger headwinds favor takeoffs (shorter runway). High temperature lowers density, resulting
in lower thrust and lift (longer runway)
• elevation of airport → at higher elevations, density if lower, hence
→ see above
• runway characteristics (such as runway gradient) → an uphill gradient
requires a longer runway
3.6
steps of design runway
• length of runway
• depends on type of traffic (local (worst) weather condition and aircraft
(most demanding aircraft)
• Airport Performance Manuals (APMs) used given.
3.7
APMs
• takeoff at zero wind, zero runway slope, and standard atmosphere (15◦C)
• temperature of 32◦C
3.8
Declared distances
• TakeOff Run Available (TORA): length of runway declared available
for ground run of airplane taking off
• TakeOff Distance Available (TODA): TORA plus length of clearway,if available
7
• Accelerate-Stop Distance Available (ASDA): TORA plus length of
stopway,if available
• Landing Distance Available (LDA): length of runway declared available for ground run of airplane landing
• Clearway(CWY): rectangular area beginning at end of runway over
which aircraft can make the initial part of their flight on takeoff (can
be on ground or water). Minimum width: 500 ft, maximum length:
1, 000 ft
• Stopway(SWY): rectangular area beginning at end of runway where aircraft can be stopped in case of aborted takeoff without structural damages.
Minimum width: 500 ft, maximum length: 1, 000 ft
• Runway threshold: beginning of portion of runway that is suitable for
landing. The threshold is often displaced from the physical beginning of
the runway for a plethora of reasons
CWY and SWY partially overlap (SWY CWY) if both are present.
In addition, the 4 distances defined a couple of slides ago might change according
to the orientation of use of a runway (asymmetry)
3.9
3.9.1
Runway capacity
Factors affecting capacity
• Number and geometric layout of runways
• Separation requirements imposed by ATM system
• Visibility
• Wind direction and strength
• Mix of aircraft
• Mix of movements per runway
• Type and location taxiways
• State and performance of ATM system
• Noise- and environmentally-related considerations
3.9.2
Number and configuration of runways
Important to distinguish
• number of runways available
• number of runways that are (or can be) simultaneously operated
8
3.10
Classes of aircraft based on Maximum TakeOff Weight
(MTOW)
• Class H: MTOW ¿ 116 ton
• Class L: 19 ton ¡ MTOW ¡ 116 ton
• Class S: MTOW ¡ 19 ton
Most wide-body jest are H, most narrow-body are L, general aviation aircraft
are generally S
3.11
Capacity of an airport
A useful way to visualize overall (hourly) capacity of an airport is a Capacity
Coverage Chart (CCC) → how much overall runway capacity is available for
what percentage of time given
• operations mix is 50% departures and 50% arrivals
• runway configuration in use at any given time is the one providing highest
capacity given prevailing weather conditions
3.12
Single runway model
• r: length of common final approach path
• vi : speedonf inalapproachof aircraf ti(assumedconstant)oi : runwayoccupancytimeof aircraf ti(f romwhenit
4
Gate Assignment
4.1
4.1.1
Introduce the Gate Assignment Problem (GAP)
What is gate assignment
A gate is an area in an airport terminal that controls access to a passenger aircraft. While the exact specifications vary from airport to airport
and country to country, most gates consist of a seated waiting area, a counter
and a doorway leading to the aircraft.
5
A complex problem, with different stakeholders and contrasting interests
5.0.1
Why complicated
• different airport size
• different airport roles (transfer passengers)
• different stakeholders
9
5.0.2
Different stakeholders
• airline operators: easy access to terminals, short ground times
• passengers: quick and smooth boarding, short walking distances, easy
access to airport amenities
• airport operators: increase in revenue, maximization of efficiency of
airport resources, minimization of congestion, delays, etc.
6
A basic MILP formulation
6.0.1
Sets of modelling
• Set of gates G = 0,1,...,m, indexed by g.
Gate 0 is a fictitious gate, i.e., the airport apron, with infinite capacity
• Set of aircraft A = 1,...,n, indexed by i or j
As an aircraft generally performs consecutive flights, we consider the arrival
time of the first flight Ai andthedeparture timeof thesecondf lightDi
6.0.2
Parameters of modelling
Parameters of gates distance:
• D0,g : walkingdistancebetweencheck−inarea(0)andgategDg1,g2 : walkingdistancebetweengatesg1andg2Dg,0
Parameter of passengers number:
• Pi,j : numberof passengersbetweenaircraf ti(inboundf light)andaircraf tj(outboundf light)P0,i : numberof pas
Different airports have a different distribution across the three types of passengers
6.0.3
Decision Variables
xi,g := 1if aircraf tiisassignedtogateg
6.0.4
Basic Constraints
6.0.5
Objective
If we focus on passengers, one option is to minimize the overall traveled distance (or time, assuming constant speed)
6.1
situations where such formulation might be limiting
6.2
linked the GAP to the Stand Allocation Problem (SAP)
6.3
some practical considerations
We assume aircraft i is the leading aircraft L and aircraft j is the
trailing aircraft T. We also know that Sij is the minimum space sep10
aration they need to satisfy (recall previous slides)
Our goal is to determine Tij, i.e., the minimum time separation between them
11