Digifly VI100, Руководство пользователя

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Observing the diagram, you can detect different values of STF related to different
air conditions. The X-axis shows horizontal speed, the Y-axis shows sink rate; in a
front wind or sink conditions, the best glide speed increases. In order to find the
optimum STF in sink, you simply add the sink of the air to the polar of your aircraft,
drawing a new polar and a new tangent line from the initial point of axes. The new
tangent OD meets the polar at the point giving a higher optimum flying speed VD
than the original optimum flying speed VB.
This function is shown on the display by 4 triangular arrows, placed 2 over and 2
under the circle of the compass; to attain STF, you have to fly at an air speed so all 4
STF arrows are not displayed. When upper arrows are displayed, you have to
speed up; when lower arrows are displayed, you have to slow down.
An acoustic STF indication can be activated by n.17
parameter, submenu
setup (1=activated); when the speed is optimal, no tones are emitted. When the
acoustic STF is activated, the acoustic sink vario is automatically disconnected.
To activate this function, go to the n. 17
parameter, submenu setup, and press
the value starts to flash; change the value using or (1=activated;
0=deactivated) and press to memorize the value.
To come back at multifunction display, press key; after beep, press key
again.
The STF has 2 adjustable
steps (n.18
parameter,
submenu setup: 1 arrow;
n.19
parameter,
submenu setup: 2 arrows)
showing speed correction
level, which is based on the
difference between your
real air speed and STF.
The following picture shows
how the VL100 display
works according on the STF
steps (STF1 step=3 km/h;
STF2 step=10 km/h).
stfs
stf1
stf2
stfs
wind
These values can be set up as explained in the section which deals with the
instrument setup.
The STF in order to work uses vario, anemometer and the wind speed and other
parameters already in memory. The wind speed can be manually inserted before
the departure (estimated wind) through the parameter wind.
It can be also calculated in real time through the graviter campass, the
anemometer and GPS setting param 20
= 0. In this case the STF is more
precise.
3.9 Ground speed
The ground speed is received from the GPS. It’s displayed on the third display from
the top of the screen when the gs icon appears. The pressure of
key, selects ias /
wind / gs display, respectively, indicated air speed, wind speed and ground speed.
Pag.15
GS