Airport Runway………….

Airport Runway

Rectangular-shaped, paved surface on an airport, designed for the landing or takeoff of airplanes.
Runways may be a man-made surface (often asphalt-concrete, or a mixture of both) or a mixture of both) or a natural surface (grass, dirt, gravel, ice or salt).

Runway Designations

Runway Incursion Avoidance

“Any occurrence at an airport involving an aircraft, vehicle, person, or object on the ground ground that creates a collision hazard or results in loss of separation with an aircraft taking off or intending to land”.
Prinarily caused by errors associated with clearances, communication, airport surface movement, and positional awareness.

Runway Length

A runway at least 6000ft (1800m) in length is usually adequate for aircraft weights below approximately 200000lb (90000kg).
Larger aircraft including wide bodies will usually require at least 8000ft (2400m) at sea level and somewhat more at higher altitude airport.
International wide body flights, which carry substantial amounts of fuel and are therefore heavier, may also have landing requirements of 10000ft (3000m) or more and takeoff requirements of 13000ft (4000m).
At sea level 10000ft(3000m) can be considered an adequate length to land virtually any aircraft.
An aircraft will need a longer runway at a higher altitude due to decreased density of air at higher altitudes, which reduces lift and engine power, requiring higher take-off and landing speed.

Runway Surface Marking

The runway centerline is a broken white stripe which indicates the center of the runway and provides alignment guidance for aircraft.
The runway edge-line is an unbroken white stripe indicating the edges of the runway, and the edges of the full-strength pavement.
Runway threshold marking identify the beginning of the runway which is available for landing.
Displaced Threshold
A threshold that is moved back usually due to obstructions, such as trees, powerlines, or buildings off the end of the runway.
This might prohibit you from making a normal descent to landing on the initial portion of the pavements.
Blast Pad/Stopway Area
Sometimes referred to as an overrun, it is different from the area preceding a displaced threshold because it cannot be used for landing, takeoff, or taxiing.
The blast pad is where propeller or jet blast can dedicate without creating a hazard to others.
The “overrun” aspect comes in the fact that the blast pad is paved, allowing aircraft more room to come to a stop after an aborted takeoff.

Runway Edge Lights

Single row of white boarding each side of runway and lights identifying the runway threshold.
Three intensity Levels: High intensity (HIRLs), Medium Intensity runway lights (MIRLs), and Low intensity runway lights (LIRLs).
Elevated edge-lights identify the runway edges during adverse visibility conditions.
Some are Pilot controlled, aimed ATC controlled.

Approach Lighting Systems

In-Runway Lighting
Some precision approach lighting systems have lights mounted flush with the surface of the runway.
The runway centerline lighting system (RCLS) is white until the last 3000ft.
From the 3000ft. point to the 1000ft. point, alternating red and white lights appear.
The remaining 1000ft. are red lights.
Touchdown Zone Lighting
Two rows of transverse light bars on either side of the runway centerline starting at 100ft. from the threshold and extending 3000ft. or to the midpoint of the runway.

Taxiway

A paved surface designed for the movement of aircraft from one part of the airport to another.
All taxiway surface markings are yellow.
Taxiway centerline marking indicate the center of the taxiway.
Double yellow taxiway edge-lines indicate the edges of the taxiway as well as the edge of full-strength pavement.
Taxiway shoulder marking consist of transverse stripes extending from the taxiway edge marking into paved areas which are not intended for aircraft use.
Paved areas which are unsuitable for aircraft may be painted green.
Runway hold lines are located on taxiway which intersect runways.
All aircraft and vehicles must hold short of the runway at the hold line.

Active Runway

The active runway is the runway at an airport that is in use for takeoffs and landings. Since takeoffs and landings are usually done as close to “into the wind” as possible, wind direction generally determines the active runway.
At controlled airports, the active is usually determined by a tower supervisor.
At major airport with multiple runways, the active could be any of a number of runways.
At major airports, the active runway is based on weather conditions (visibility and ceiling), as well as wind, and runway conditions such as wet/dry or snow covered), efficiency, traffic demand and time of day.

Runway Safety

Runway excursion- an incident involving only a single aircraft, where it makes an inappropriate exit from the runway.
Runway overrun- a type of excursion where the aircraft is unable to stop before the end of the runway.
Runway incursion- an incident involving incorrect presence of a vehicle, person or another aircraft on the runway.
Runway confusion- an aircraft makes use of the wrong runway for landing or take-off.

Pavement

The choice of material used to construct the runway depends on the use and the local ground consitions.
For a major airport, where the ground conditions permit, the most satisfactory type of pavement for long-term minimum maintenance is concrete.
Although certain airports have used reinforcement in concrete pavements, yhis is generally found to be unnecessary, with the exception of expansion joints across the runway where a dowel assembly, which permits relative movement of the concrete slabs, is placed in the concrete.
Post-tensioning concrete has been developed for the runway surface. This permits the use of thinner pavements and should result in longer concrete pavement life.

CONCRETE CIVIL