Trio Avionics Pro Pilot - Manual (Page 32)

Trio Pro Pilot Manual 3.8
32
Chapter 8
Vertical Operation
Vertical Navigation (V NAV)
Generally speaking, except for warnings and alerts,
the display screen will present the Vertical Navigation
information on the right hand half of the display
screen when the encoder has been assigned to the
VNAV functions.
To view and control the vertical functions it is
necessary to press the V MODE button one time to
transfer encoder control to the V NAV functions.
Pressing the V NAV button once will dedicate the
right hand half of the display to the V NAV functions
(and the mid upper arrow will point to the right). No
navigation changes will occur.
Altitude Hold (ALT HLD)
In the example shown the pilot has pushed the V MODE button one time to transfer encoder control to
the V NAV functions (arrow points to the right).
Here, the “V” LED is illuminated, indicating that the pilot has pressed the V NAV button and the autopilot
pitch servo is engaged and holding altitude. Additionally, the ALT HLD green LED will illuminate to show
that the autopilot is in the Altitude Hold mode.
Rotating the encoder knob will then adjust the altitude up or
down by about 5 feet per “click” on the encoder (Rotate
clockwise to go up and rotate counterclockwise to go down).
The message “ALT ADJ” will then appear on the screen to indicate that a slow altitude change is
underway. In addition, the ALT HLD green LED will flash while the altitude change is in progress. The
“UP/DN message will change to read either “UP” or “DN” depending upon which direction the knob was
rotated.
Once the commanded altitude has been reached, the LED will stop flashing and the display will revert
back to showing normal ALT HLD message.
NOTE: This function is used only for slight changes in altitude, such as adjusting for a change in
barometric pressure on a cross country flight. After adjusting the primary aircraft altimeter, the
Pro Pilot may be slightly off altitude.
Minor altitude adjustments will be made at about 100 fpm. If the required altitude correction is more
than 30 or 40 feet, the pilot may simply rotate the encoder knob slowly a couple of times to initiate the
gradual climb or descent and then, when the desired altitude is reached, press the encoder knob
momentarily to once again hold the current altitude.