7.2 Runway Design
7.2.1 Runway Length:
Airplanes today operate on a wide range of available runway lengths. Various factors, in
turn, govern the suitability of those available runway lengths, most notably airport
elevation above mean sea level, temperature, wind velocity, airplane operating weights,
takeoff and landing flap settings, runway surface condition (dry or wet), effective runway
gradient, presence of obstructions in the vicinity of the airport. In summary, the goal is to
construct an available runway length for new runways or extensions to existing runways
that is suitable for the forecasted critical design airplanes.
Assumptions:▪ Design Assumptions: The assumptions used by this design are approaches and departures with
no obstructions, zero wind, dry runway surfaces, and zero effective runway gradient.
▪ Critical Design Airplanes: The airplane that results in the longest recommended
runway length is a large airplane of 60,000 pounds weight (27,200 kg) or more. When
the maximum takeoff weight is over 60,000 pounds, the recommended runway length
is determined according to individual airplanes. The largest airplane in the world,
Airbus A- 380 - 800, will be the critical design airplane.
▪ Design Conditions:
a- Airport Elevation: At mean sea level (0.00 ft).b- The mean daily maximum temperature of the hottest month at the airport
(Table 3-1) is 40.2 C (104.36F).