Last reviewed 16 Sept 2026 · Facts as of 16 Sept 2026 · 11 min read
Aircraft characteristics affecting airport design
| Characteristic | Influence on design |
|---|---|
| Type of propulsion (piston, turboprop, jet) | Runway length, noise, jet blast |
| Size — wingspan, fuselage length, height | Runway and taxiway widths, separation, apron and hangar size, gate positions |
| Minimum turning radius | Taxiway curves, apron layout |
| Minimum circling radius in flight | Airspace, spacing between airports |
| Speed | Airspace use, runway exit design |
| Capacity (passengers, cargo) | Terminal building and apron facilities |
| Weight (maximum take-off weight, landing weight) and gear configuration (wheel base, tread) | Pavement thickness, runway length |
| Jet blast, fuel spillage, noise | Blast fences, pavement type near aprons, land-use planning |
Airport site selection
Factors considered:
- Regional plan and airport type (domestic/international, civil/military).
- Proximity to other airports — non-interference of air traffic patterns.
- Ground accessibility — travel time from the city; road and rail links.
- Topography — level land, minimum earthwork; freedom from flooding.
- Obstructions — hills, towers and tall buildings must not penetrate approach and other imaginary surfaces.
- Visibility — freedom from fog, smoke and haze (industrial areas).
- Wind direction and intensity — for runway orientation.
- Noise nuisance — away from dense residential areas; compatible land use.
- Soil and drainage — good bearing capacity, low water table.
- Future expansion — adequate land.
- Utilities — water, power, telecommunications.
- Economy — land cost, construction cost.
- Bird hazard — away from garbage dumps, slaughterhouses and water bodies attracting birds.
ICAO aerodrome reference code
The code relates aircraft characteristics to aerodrome facilities.
| Code number | Aeroplane reference field length |
|---|---|
| 1 | Less than 800 m |
| 2 | 800 m to less than 1200 m |
| 3 | 1200 m to less than 1800 m |
| 4 | 1800 m and above |
| Code letter | Wingspan |
|---|---|
| A | Up to (but less than) 15 m |
| B | 15 m to less than 24 m |
| C | 24 m to less than 36 m |
| D | 36 m to less than 52 m |
| E | 52 m to less than 65 m |
| F | 65 m to less than 80 m |
E.g. 4E for large wide-body jets; 4C for narrow-body jets such as common single-aisle airliners.
Components of an airport
Airside: runways, taxiways, holding bays, aprons, hangars, fuel facilities, air traffic control tower, navigational and visual aids, fire and rescue services. Landside: terminal building, car parks, access roads, cargo terminals, utilities, administrative buildings.
Runway orientation
Runways are oriented along the direction of prevailing winds so that aircraft take off and land into the wind (increasing lift, reducing ground run) and crosswind components are within safe limits.
Wind rose diagram
- Type I — shows direction and duration (percentage of time) of winds; radial lines proportional to wind duration in each direction; runway placed along the longest line.
- Type II — shows direction, duration and intensity; concentric circles for wind speed ranges; a transparent strip of width equal to twice the permissible crosswind component is rotated over the diagram to find the orientation giving maximum wind coverage (usability).
Crosswind component ( = wind speed, = angle between wind direction and runway).
ICAO recommendations: runway usability factor at least 95%, with maximum permissible crosswind components of about 37 km/h (20 knots) for aircraft needing a reference field length of 1500 m or more, 24 km/h (13 knots) for 1200–1500 m, and 19 km/h (10 knots) for less than 1200 m.
Runway designation: runway ends are numbered by their magnetic bearing divided by 10, rounded (e.g. a runway oriented 272° magnetic is "27", its reciprocal end "09"); parallel runways add L, C, R.
Runway configurations
Single runway, parallel runways (close, intermediate or wide spacing), intersecting runways, open-V runways, and combinations — selected based on traffic volume, wind coverage and land availability.
Runway length
Basic runway length
The length required under standard conditions: airport at mean sea level, standard atmosphere (15 °C at sea level), zero effective gradient, no wind, aircraft at maximum take-off/landing weight. Considered cases:
- Normal landing — aircraft must stop within a proportion of the runway.
- Normal take-off — with a margin.
- Engine failure — the runway must allow either continued take-off or aborted (rejected) take-off and stopping; this defines the balanced field length.
Clearway — an area beyond the runway end, free of obstacles, over which the aircraft makes its initial climb. Stopway — a paved area beyond the runway end that can support an aircraft during an aborted take-off.
Corrections to basic runway length (ICAO/FAA)
1. Elevation: increase by 7% for every 300 m of elevation above mean sea level.
2. Temperature: the elevation-corrected length is increased by 1% for every 1 °C by which the airport reference temperature (ART) exceeds the standard atmospheric temperature at that elevation:
= monthly mean of average daily temperatures for the hottest month; = monthly mean of maximum daily temperatures for the same month.
If the combined elevation and temperature correction exceeds 35% of the basic length, a specific study is recommended.
3. Effective gradient (FAA): increase the corrected length by 20% for every 1% of effective gradient (difference between highest and lowest runway elevations ÷ runway length).
Runway geometric elements
- Runway width — depends on code letter/number (wider for larger aircraft).
- Longitudinal gradient — limited (ICAO: about 1.25% maximum for code number 4 runways, 1.5% for code 3, 2% for codes 1 and 2), with limits on changes of gradient and sight distance along the runway.
- Transverse slope — for drainage (typically about 1–1.5%).
- Runway shoulders, runway strip (graded area around the runway), runway end safety area (RESA), blast pads.
Taxiways
Taxiways connect runways with aprons, hangars and terminals. Design considerations: shortest practicable routes, avoid crossing active runways, adequate width and separation, smooth curves, sight distance.
Exit taxiways
- High-speed (rapid) exit taxiways allow landing aircraft to leave the runway at higher speeds, increasing runway capacity.
- Commonly angled at about 30° to the runway (ICAO range about 25°–45°).
Radius for an exit taxiway at a given turn-off speed:
( in m, in km/h.)
Horonjeff's formula for the radius of taxiway curves (to keep the main gear on the pavement):
= wheel base (m); = taxiway width (m); = distance between the midway point of the main gears and the edge of the taxiway pavement (m).