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Trio Pro Pilot Manual 4.1
11
Chapter 2
Vertical Navigation Overview (VNAV)
The
V NAV
function of the Pro Pilot controls the pitch axis of the aircraft. It provides commands to the
pitch servo that attaches to the elevator control system. The
V NAV
system uses a rate gyro, pressure
sensors, airspeed sensors and accelerometers as primary references in controlling the pitch attitude of
the aircraft. The V NAV system does not depend upon a GPS signal for its functions.
Operation
While the Pro Pilot also has several vertical functions, the basic mode is that of “
ALTITUDE HOLD.
” A
manual climb to altitude desired and a single press of the
V NAV
button will engage the pitch servo and
maintain that altitude.
Three vertical navigation modes allow the pilot to maintain altitude, climb/descend at a selected vertical
rate (in feet per minute) and preselect a target altitude. An additional pilot controlled steering capability
allows the pilot to choose airspeed instead of vertical speed for the climb/descent by use of a button on
the stick or yoke.
Basic V NAV Operation Modes
The capabilities of the
V NAV
system comprise three basic modes:
1. Altitude
hold
2. Vertical climb and descent rates, and airspeed capture and control
3. Altitude pre-select, which can be used in conjunction with the vertical modes
Minimum and maximum safe airspeed management modes are also included to prevent stalling and
over-speeding the aircraft.
Altitude Hold
To operate the altitude hold, fly to the desired altitude and level the aircraft in trim. Press the
V NAV
button to engage the pitch servo and the aircraft will hold at that altitude. Press the
V MODE
button and
then rotate the encoder knob for minor adjustments to accommodate barometer updates.
Manually fly the plane to the desired altitude and
engage the Altitude hold