Page 275 - Planning and Design of Airports
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236     Airp o r t  D e sign


                     10.  Sufficient distance must be provided to comfortably deceler-
                        ate an aircraft after it leaves the runway. It is suggested that
                        for the present this distance be based on an average rate of
                        deceleration of 3.3 ft/s . This applies only to transport cate-
                                           2
                        gory aircraft. Until more experience is gained with this type
                        of operation the stopping distance should be measured from
                        the edge of the runway.
                    A chart showing the relationship of exit speed to radii R  and R ,
                                                                   1      2
                 and length of transition curve L  is given in Fig. 6-33.
                                           1
                    ICAO has indicated the relationship between aircraft speed and
                 the radius of curvature of taxiway curves as illustrated in Table 6-22.
                 For high-speed exit taxiways ICAO recommends a minimum radius

                4000


                3600

                               L       R 2
                3200           1
                               R
                                1
                2800                                               350
                            R  = radius of entrance curve
                             1
                            L  = length of entrance curve
                            1
                2400                                               300
                            R 2  = radius of central curve  Length L 1
               Radius in feet  2000                                250  L 1 , in feet



                1600                       Radius R 1              200


                1200                                               150
                                           Radius R 2
                 800                                               100


                 400                                               50


                   0                                               0
                    0     10     20    30     40    50     60     70
                                   Speed, in miles per hour
            FIGURE 6-33  Radii of curvature and entrance curves for taxiways.
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