Runway

A runway (also abbreviated to RWY) is a strip of land on an airport, on which aircraft can take off and land. Runways may be a man-made surface (often asphalt, concrete, or a mixture of both) or a natural surface (grass, dirt, or gravel).

Aerial picture of a runway of Chennai International Airport, Chennai, India

Sections of a runway

• The Runway Safety Area is the cleared, smoothed and graded area around the paved runway. It is kept free from any obstacles that might impede flight or ground roll of aircraft.
• The Runway is the surface from threshold to threshold, which typically features threshold markings, numbers, centerlines, but not overrun areas at both ends.
• Blast pads, also known as overrun areas or stopways, are often constructed just before the start of a runway where jet blast produced by large planes during the takeoff roll could otherwise erode the ground and eventually damage the runway. Overrun areas are also constructed at the end of runways as emergency space to slowly stop planes that overrun the runway on a landing gone wrong, or to slowly stop a plane on a rejected takeoff or a take-off gone wrong. Blast pads are often not as strong as the main paved surface of the runway and are marked with yellow chevrons. Planes are not allowed to taxi, take-off or land on blast pads, except in an emergency.

• Displaced thresholds may be used for taxiing, takeoff, and landing rollout, but not for touchdown. A displaced threshold often exists because obstacles just before the runway, runway strength, or noise restrictions may make the beginning section of runway unsuitable for landings. It is marked with white paint arrows that lead up to the beginning of the landing portion of the runway.