This document provides information on geometric design considerations for airport runways, taxiways, and terminals. It discusses factors that influence runway orientation such as wind conditions and aircraft performance. It also describes guidelines for determining basic runway length based on elevation, temperature, and aircraft characteristics. Additional topics covered include runway configuration, geometry standards for length, width, gradients and sight distances, taxiway design standards, and concepts for terminal area layout and space requirements.

1. 1

2. GEOMETRIC DESIGN
 Runway
1. Runway orientation
2. Basic Runway length
3. Runway configuration
4. Runway Geometrics
 Taxiway
 Exit taxiway
Terminal Design
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3. RUNWAY
 A runway is a rectangular area on the airport surface prepared
for the takeoff and landing of aircraft.
 An airport may have one runway or several runways which are
sited, oriented, and configured in a manner to provide for the
safe and efficient use of the airport under a variety of
conditions.
 Several of the factors which affect the location, orientation,
and number of runways at an airport include local weather
conditions, particularly wind distribution and visibility, the
topography of the airport and surrounding area, the type and
amount of air traffic to be serviced at the airport, aircraft
performance requirements, and aircraft noise.
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4. RUNWAY ORIENTATION
 Runway are always oriented in the direction of prevailing
winds.
 The reason behind this is to utilize the maximum force of
the wind at the time of take-off and landing of an aircraft.
 Following points need to be considered while orienting the
runways:
 Avoiding delay in the landing, taxing and take-off operations.
 Providing the shortest taxi distance possible from the terminal
area to the ends of runway.
 Making provision for maximum taxiways so that the landing
aircraft can leave the runway as quickly as possible to the
terminal area
 Providing adequate separation in the air traffic pattern 4

5.  Data required for runway orientation
 Map of area and contours
 Wind data
 Wind Direction: Tail Wind, Cross Wind & Head Wind
 Fog characteristics
 ICAO recommends maximum allowable cross wind
components as
Field Length Maximum CW component
1500 or over 37 km/hr
1200 to 1499 m 24 km/hr
Less than 1200 m 19 km/hr
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6.  Wind Coverage
 Wind coverage of airport is the percentage of time in a year
during which the cross wind component remains within the
limit or runway system is not restricted because of excessive
cross wind. ICAO recommends minimum wind coverage of
95%
 Calm Period
 This is the period for which the wind intensity remains below
6.4 km/hr
 Wind Rose Diagram
 Type 1: Duration and Direction of wind
 Type 2: Duration, Direction and Intensity of wind
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7. BASIC RUNWAY LENGTH
 The FAA’s procedure for estimating runway length is based
on the following data:
1. Designation of a critical aircraft.
2. The maximum takeoff weight of the critical aircraft at the
airport.
3. The airport elevation.
4. The mean daily maximum temperature for the hottest
month at the airport.
5. The maximum difference in elevation along the runway
centerline.
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8. Correction for Elevation
As the elevation increases, the air density reduces. This in
turn reduces the lift on the wings of the aircraft and the
aircraft requires greater ground speed before it can rise into
the air. To achieve greater speed, longer length of runway is
required.
ICAO recommends that the basic runway length should be
increased at the rate of 7% per 300m rise in elevation above
MSL.
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9. Correction for Temperature
The rise in airport reference temperature has the same effect
as that of the increase in elevation. Airport reference
temperature is defined as the monthly mean of average daily
temperature (Ta) for the hottest month of the year plus one
third of the difference of this temperature and the monthly
mean of the maximum daily temperature (Tm)
Airport reference temperature = Ta + [(Tm – Ta)/3]
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10.  ICAO recommends that the basic runway length after having been
corrected for elevation, should be further increased at the rate of 1%
for every 10 C rise of airport reference temperature above the
standard atmospheric temperature at that elevation.
 The standard atmospheric temperature at the site can be determined
by reducing the standard sea level temperature of 150 C at the rate of
6.50 C per 1000 m rise in elevation.
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11.  Check for Total Correction for Elevation and Temperature
ICAO further recommends that, if the total correction for
elevation plus temperature exceeds 35% of the base runway
length, these corrections should then be further checked up by
conducting specific studies at the site by model tests.
Correction for Gradient
Steeper gradient results in greater consumption of energy and as
such longer length of runway is required to attain the desired
ground speed. FAA recommends that the runway length after
having being corrected for elevation and temperature should be
further increased at the rate of 20% for every 1% of effective
gradient.
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12. RUNWAY LENGTH CURVE
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13. Basic Runway Length
 Normal Landing
 The aircraft should come to a stop within 60% of landing
distance assuming that the pilot makes an approach at the
proper speed and crosses the threshold of the runway at a
height of 15m.
 The runway of full strength is to be provided for the entire
landing distance
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14.  Normal Take-off
 The take-off distance must be 115% of the actual distance
the aircraft uses to reach a height of 10.5 m.
 It requires a clearway at the end of the runway in the
direction of take-off. This should not be less than 15m wide.
The upward slope of clearway from the end of the runway
shall not exceed 1.25%
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15. 15

16.  Stopping in Emergency
 Require either clearway or a stopway, or both.
(Stopway: Used for decelerating the aircraft and bringing it
to a stop during an aborted take-off.)
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17. RUNWAY CONFIGURATION
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18. RUNWAY GEOMETRICS
 Length of runway
 Width of runway
 Sight distance
 Longitudinal and effective gradient
 Rate of Change of longitudinal gradient
 Transverse gradient
 Safety area
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19. Length and Width of Runway
 Classifications of airports as per ICAO
Airport Type
Basic Runway Length (m) Width of
Runway
Pavement
(m)
Maximum
Longitudinal
Gradient
(%)Maximum Minimum
A Over 2100 2100 45 1.5
B 2099 1500 45 1.5
C 1499 900 30 1.5
D 899 750 22.5 2.0
E 749 600 18 2.0 19

20. Sight Distance
 No sight distance restrictions, as the longitudinal gradients
for the runway are less.
 Adherence to runway longitudinal gradient standards
provides adequate line of sight.
Airport Category Y (m) X
ICAO code letter A 1.5
Half runway
length
ICAO code letter B 2.1
Half runway
length
ICAO code letter C,D
and E
3.0
Half runway
length
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21. Longitudinal Gradient
 The longitudinal gradient increases in required runway
length.
 It also affects the aircraft performance.
 These should be as flat as possible to avoid excessive
engine thrust
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22. Change of Longitudinal Gradient
 The abrupt grade change may cause premature lift-off of
aircraft during take off.
 The change in gradient should be smooth through the
provision of vertical curves.
 No vertical curve is required if the grade change is less
than 0.4 %.
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23. Transverse Gradient
 Provided for quick disposal of surface water.
 Ponding of water is hazardous for aircraft operation.
 Minimum recommended transverse slope is 1%.
 For rigid pavement it may be kept as low as 0.5.
 Slope up to 2% are permitted for runways that serve smaller
classes of aircraft. For other runways maximum transverse slope
is 1.5%.
 For shoulders slope of 3-5% is recommended.
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24. Safety Area
 The safety area is an area which is cleared, drained and
graded. It includes the structural pavement, shoulders on
either side of runway and the additional width.
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25. TAXIWAY
 Taxiway are defined as paths on the airfield surface for the
taxing of aircraft and are intended to provide linkage
between one part of the airfield.
 Aircraft movement on taxiways are essentially ground
movements and are relatively slow.
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26.  Types of taxiway
 Apron taxiway: Located on the periphery of an
apron to provide uninterrupted taxing of aircraft
across the apron.
 Dual parallel taxiway: Two parallel taxiways on
which aircraft can taxi in opposite directions.
 Terminal taxiway: It is a portion of an apron
intended to provide access to only aircraft stands or
gate positions.
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27. Taxiway Geometrics
 Length
 As short as possible
 It will increase as number of taxiways have to be provided along the
runway.
 Longitudinal Gradient
 Level taxiways are operationally more desirable
 If gradient is steep it affects fuel consumption
 As per ICAO gradient of 3% for A and B types of airport and 1.5%
for C, D and E types of airport. 27

28.  Width of taxiway
 Width of taxiway is lesser than runway, as aircraft is not
airborne and speeds are small.
 There is not much variability in the maneuverability of
aircraft and nose of aircraft follows the taxiway centerline.
 Width varies between 22.5 and 7.5
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29.  Sight distance
 As speed of aircraft on taxiway is lower than the speed on
runway, the smaller value of sight distance will be sufficient
on the taxiway.
Airport Type Y (m) X (m)
A 1.5 150
B 2.0 200
C, D and E 3.0 300
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30.  Turning Radius
 Change in aircraft path is done by providing a horizontal
curve.
 The design should be such that the aircraft can negotiate the
curve without significantly reducing the speed.
 Relationship between exit speed and radius of curve
Radius = V2/125f;
V is in Kmph and f is coefficient of friction =0.13
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31. • ICAO has indicated the relationship between aircraft speed and the radius of
curvature of taxiway curves as illustrated in Table.
TAXIING SPEED(kmph) RADIUS OF EXIT CURVE
(m)
16 15
32 60
48 135
64 240
80 375
96 540
Source: International Civil Aviation Organization
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32. Radii of curvature and entrance curves for
Taxiways
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33. EXIT TAXIWAY
 The function of exit taxiways, or runway turnoffs as they
are sometimes called, is to minimize runway occupancy
by landing aircraft.
 Exit taxiways can be placed at right angles to the runway
or some other angle to the runway.
 When the angle is on the order of 30°, the term high-speed
exit is often used to denote that it is designed for higher
speeds than other exit taxiway configurations.
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34. HIGH SPEED EXIT TAXIWAY
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35. COMMON EXIT TAXIWAY
CONFIGURATION
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36. FAA Taxiway Curvature Dimensional
Standards (ft)
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37. TERMINAL AREA
 It is portion of an airport other than landing area.
 It serves as a focal point for the activities on the airport.
 Terminal area includes
 Terminal and operational buildings
 Vehicle parking area
 Aircraft service hangars
 Facilities for cargo handling and storage
 Facilities for passengers
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38. 38

39.  Terminal building usually refers to a building mainly, used for
passengers, airline and administration facilities.
 Its layout is such as to offer the enplaning passengers, the
convenient and direct access from the vehicle platform or street
side of the building, through booking and waiting rooms, to the
aircraft loading positions on the apron.
 Deplaning passengers are also provided with a direct route from
the aircraft to the baggage claim counter and then to the vehicle
platform.
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40. GENERAL AIRPORT TERMINAL
LAYOUT
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41. CONCEPTFOR TERMINAL DESIGN
 Horizontal distribution concept
1. Pier or finger concept
2. Satellite concept
3. Linear concept
4. Transporter concept
 Vertical distribution concept
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42. Horizontal distribution concept
 Pier or finger concept:
 The pier concept has an interface with aircraft along piers
extending from the main terminal.
 Aircraft are usually arranged around the axis of the pier in a
parallel or nose-in parking alignment.
 Each pier has a row of aircraft gate positions on both sides,
with a passenger concourse along the axis which serves as
the departure lounge and circulation space for both
enplaning and deplaning passengers.
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43.  Satellite concept:
 The satellite concept consists of a building, surrounded by
aircraft, which is separated from the terminal and is
usually reached by means of a surface, underground, or
above ground connector.
 The aircraft are normally parked in radial or parallel
positions around the satellite.
 Linear concept:
 The simple linear terminal consists of a common waiting
and ticketing area with exits leading to the aircraft parking
apron.
 It is adaptable to airports with low airline activity which
will usually have an apron providing close-in parking for
three to six commercial passenger aircraft
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44.  Transporter concept:
 Aircraft and aircraft servicing functions in the
transporter concept are remotely located from the
terminal.
 The connection to the terminal is provided by vehicular
transport for enplaning and deplaning passengers.
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45. Terminal
Types
Linear
Curvilinear
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46. Finger Piers
Satellite
Transporter
Satellite
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47. VERTICAL DISTRIBUTION CONCEPT
 The basis for distributing the primary processing
activities in a passenger terminal among several levels
is mainly to separate the flow of arriving and departing
passengers.
 The decision concerning the number of levels a
terminal facility should have depends primarily on the
volume of passengers and the availability of land for
expansion in the immediate vicinity.
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48. VERTICAL DISTRIBUTION CONCEPT: (a)single level (b)second level loading (c)two
level system. (FAA)
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49.  The operational category includes control tower, weather bureau and other
government services related to the aviation. In many cases terminal building
fulfils the function of the operational building as well
 The various facilities provided in the airport buildings are as follows:
• Booking counter
• Baggage claim section
• Enquiry counter
• Space for cargo processing
• Public telephone booth
• Waiting hall
• Sanitation facilities
• Restaurants/Hotels
• First aid room
• General store and gift shops
• Space for magazines, news
papers etc
• Office space for airport
staff
• Weather bureau
• Post office and banking
facilities
• Custom control
• Passport and health control
• Control tower
FAA suggests that the terminal
building area should be based on the
present and future peak-hour
passenger activities projected over a
period of 10 years.
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50. TERMINAL BUILDING SPACE
REQIREMENT
Component
Space Required in meter square Typical Peak
Hour per Passenger
Ticket lobby 1.0
Baggage claim 1.0
Departure lounge 2.0
Waiting rooms 1.5
Immigration 1.0
Customs 3.0
Amenities 2.0
Airline operations 5.0
Total gross area
Domestic 25.0
International 30.0
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51. REFERENCE
 Planning and design of airports.
 Robert horonjeff.
 Francis x. makelvey.
 William j. sproule.
 Seth b. young.
 Airport system.
 Richard de neufville
 Amedeo R. odoni
 Transportation engineering
 Paul H. wright
 Norman J. ashford
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