Runway

A runway is a defined rectangular area on an aerodrome prepared for the landing and take-off of aircraft. Runways are identified by number (magnetic heading rounded to the nearest 10°, divided by 10 — e.g., Runway 27 faces approximately 270° magnetic) and by suffix (L, C, R for parallel runways).

Runway Dimensions

Runway dimensions vary enormously. A grass strip for ultralights may be 300 m long and 20 m wide. A major international airport’s primary runway may be 3,658 m (12,000 ft) long and 60 m wide. Landing distance calculations must account for the actual declared distances: TORA (Take-Off Run Available), TODA (Take-Off Distance Available), ASDA (Accelerate-Stop Distance Available), and LDA (Landing Distance Available).

Runway Markings

• Runway designator: numbers and letters painted in white at each end
• Centreline: dashed white line along the runway length
• Threshold: transverse white bars marking the beginning of the landing surface
• Touchdown zone: white bars indicating the first 3,000 ft from the threshold
• Fixed-distance markers: at 500 m intervals
• Precision runway markings include all of the above plus aiming point markings

Related Terms

See also: Active Runway, Threshold, Displaced Threshold.