Assignment 5: Geometric Design Standards

CEE 4674 Homework 5 Spring 2009Aircraft Group Parameters ResultsSmall single-engine GAaircraftBusiness jetsMedium-size transportaircraftApproach speed = 110 knotsTouchdown location = 275metersAverage deceleration = -1.3 m/s-sFree roll time = 2.5 secondsApproach speed = 125 knotsTouchdown location = 350meters Average deceleration =-1.4 m/s-sFree roll time = 2.0 secondsApproach speed = 140 knotsTouchdown location = 420meters Average deceleration =-1.4 m/s-sFree roll time = 2.0 secondsFlare distance = 275 metersTransition distance = 135.6 metersBraking distance = 980.6 metersTotal Distance to Runway Exit = 1391.2metersFlare distance = 350 metersTransition distance = 123.0 metersBraking distance = 1188.5 metersTotal Distance to Runway Exit = 1661.5metersFlare distance = 420 metersTransition distance = 137.7 metersBraking distance = 1510.5 metersTotal Distance to Runway Exit = 2068.2metersThe solution to the problem assumes a typical exit speed of 8 knots. This is consistent with observed values for rightanglerunway exits. Since the runway is 9000 feet long (2744 meters), we can sketch the following diagrams. Figure 11shows the recommended solution to the problem using the runway from both directions. Note that a single runway exitis located at the midpoint (1372 meters) to service small aircraft. This location is 20 meters from the optimal locationand seems a reasonable tradeoff to avoid two runway exits 40 meters apart. Figure 12 illustrates a solution with 3runway exits.Figure 10. One Direction Runway Exit Locations. Locations in Meters from Runway Threshold.Figure 11. Bi-Directional Runway Exit Locations. Locations in Meters from Each Runway Threshold. Five Runway ExitsPlus two Runway End Exits. 7