RNG PULL SCAN PUSH ON BRT PROC CRSR MSG OBS ALT NRST CLR ENT D MENU DTK 060 TK 0.3nm 108 kt LEG APT VOR NDB INT USR ACT FPL SET AUX NAV 1 0.01nm :5.0nm 00:10 WPT Turn anticipation advises you to begin your turn to  the desired track to the next waypoint in the flight  route. Turn anticipation is indicated on this computer  when the WPT message stops flashing. 0 3 Waypoint alerting provides a flashing message when you approach the vicinity of the active waypoint. Fly-by Fly-over Figure 3-19. Fly-by and fly-over waypoints. Figure 3-18. Waypoint alerting and turn anticipation. Waypoint Alerting Turn Anticipation Waypoint Sequencing RNG PULL SCAN PUSH ON BRT PROC CRSR MSG OBS ALT NRST CLR ENT D MENU DTK 051 049 TK 18.2 nm 110 kt LEG APT VOR NDB INT USR ACT FPL SET AUX NAV 1 0.01nm :5.0nm WPT 18 2 The waypoint sequencing function makes the next waypoint in the flight plan sequence the new active waypoint. Figure 3-20. Waypoint sequencing. Awareness: Making Waypoint Callouts The first service performed by the sequencing mode  is waypoint alerting. Just prior to reaching each active  waypoint, waypoint alerting advises the pilot of imminent  arrival at the active waypoint. Waypoint alerting is illustrated  in  Figure 3-18. The second service performed by the sequencing mode is  turn anticipation. During waypoint alerting and prior to  reaching the active waypoint, the FMS indicates that it is  time to begin the turn to fly the desired track to the new  active waypoint. The timing of turn anticipation is based on  the aircraft’s observed groundspeed and the angle of the turn  required to track to the next waypoint. If a standard rate turn  is begun when the waypoint alerting indication is presented,  the pilot should roll out on course when the aircraft reaches  the center of the desired track to the new active waypoint.  Turn anticipation is also illustrated in  Figure 3-18. The third service performed by sequencing mode is waypoint  sequencing. Once the aircraft reaches the active waypoint,  the FMS automatically makes the next waypoint in the flight  plan sequence the new active waypoint. Waypoint sequencing  is illustrated in  Figure 3-20. When turn anticipation is used, the aircraft does not fly  directly over the active waypoint. Rather, the computer  commands a turn that “rounds the corner” to some degree,  giving priority to having the aircraft roll out on the new  desired track to the new active waypoint. This function is  illustrated in the upper illustration in  Figure 3-19. Turn anticipation occurs only when the active waypoint is  designated as a fly-by waypoint. A fly-by waypoint is one  for which the computer uses a less stringent standard for  determining when the aircraft has reached it. By contrast,  some waypoints are designated as flyover waypoints. The  FMS will not use turn anticipation for a fly-over waypoint;  instead, the navigation will lead the aircraft directly over the  waypoint (hence the name). A missed approach waypoint is a  typical example of a fly-over waypoint. A fly-over waypoint  is illustrated in  Figure 3-19. To help you stay in touch with the progress of the flight while  the FMS automatically performs the navigation task, it is  a good practice to announce your arrival (mentally, single  pilot; or orally, to the flight crew) at each waypoint in the  programmed route. For example, when arriving at SUNOL  intersection, you might announce, “Arriving at SUNOL.  3-15