Joined: 11 Dec 2005
|Posted: Wed Aug 15, 2012 5:04 pm Post subject: FMC Descent
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Shows Climb, Cruise and Descent Pages
Speed Transition (SPD TRANS)
The transition speed is usually 10 knots less than the destination airport limiting speed from the navigation database. When no airport limit speed exists, the default speed of 240 knots displays.
The transition altitude is the point the transition speed is active for the destination airport. When no altitude exists in the navigation database, the default of 10,000 feet displays.
Flight Path Angle, Vertical Bearing, and Vertical Speed (FPA, V/B,V/S)
• FPA - displays the current airplane flight path angle whenever the airplane descends
• V/B - displays vertical bearing from current position to the displayed waypoint and altitude
• V/S - displays required vertical speed to maintain the vertical bearing
Descend To (DES TO)
The waypoint for a direct–to descent. Usually, this is the E/D waypoint from the active route.
Manual entry of waypoints on or off of the route are allowed.
The DTG calculations are for a descent direct to the selected waypoint.
A clean circle assumes no drag devices are used for descent.
TO CLEAN distance is the distance to the clean descent circle.
If the distance is negative it means that clean circle is already crossed and a clean descent is not possible.
A direct descent to the DES TO waypoint at a SPD/ALT constraint is possible when the airplane is outside the clean circle.
The clean circle displays on the ND when the DISPLAY prompt is ON.
A drag circle assumes speedbrakes are UP for descent.
TO DRAG distance is the distance to the drag descent circle.
If the distance is negative it means the drag circel is already crossed and a drag descent is no longer possible.
A direct descent to the DES TO waypoint at a SPD/ALT constraint is possible when the airplane is outside the drag circle.
The drag circle displays on the ND when the DISPLAY prompt is ON and the airplane is inside the clean circle.
Clean and Drag Circles
Automatically changes to OFF within 150 feet of the waypoint constraint altitude.