Flytec 5020 v1.18 * - Manual (Page 16)

Flytec 5020 technical manual
Following different types of Glide ratio can be selected within the user-selectable fields.
• Glide ratio through the air:
L/D air =TAS / Sink True airspeed divided by sink
• Glide ratio over the ground:
L/D gnd = GS/Sink Ground speed divided by sink
• Required glide ratio in order to reach the chosen destination from the present
position.
L/D req. = Distance to the waypoint divided by the height difference to the waypoint.
Best glide 8
Act. Distance to goal 5.45 km
Best glide –leave
point 931m over
goal
Akt. Höhe
956m
Alt a BG
275m
681m
2km
L/D req 5.7
• Required glide ratio in order to reach the goal of an active route, from the present
position.
L/D r.Gl. = Distance to the goal over the next waypoints of a route divided by the height
difference to the waypoint. This userfield is only active if a route is active. With this L/D the
pilot can decide if he would fly directly to the goal or if he need to take altitude in a thermal.
The calculation does not take into account if one ore more waypoints between the actual
position and goal are higher than the direct beam from the actual position into goal. The
distance to goal is calculated as described in chapter 7.10.
7.6 Head, Cross and Tail Winds; the Wind Component
During a goal flight or in calculating a final glide, it is the wind component (i.e. the difference
between Ground speed and Air speed) that is important. In most cases the wind does not
blow directly from the front or from behind, but from the side. If the wind component “Spd-
Diff’ (in the user defined fields) is positive, then the pilot will fly with a tail wind and the glide
ratio over the ground will improve. If it is negative the glide ratio will worsen. The Flytec 5020
takes the wind into consideration when calculating the final glide. (In order to find the correct
angle between the destination and the wind when a strong cross wind is present, please
refer to the section Goto function.) The calculated wind speed can be displayed in a user
selectable field.
Note: If the wind sack covers the wind directions N E S or W, the letter disappears.
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