Trio Avionics Pro Pilot - Manual (Page 43)

Trio Pro Pilot Manual 3.8
43
Approaches
 The approach will normally begin with the Pro Pilot in the ALT HLD (Altitude Hold) mode,
although the autopilot VS mode or externally (EFIS) generated vertical navigation may be active.
 When the vertical data signal becomes valid, the blue GPSV LED will blink and the autopilot will
be forced automatically to the ALT HLD mode. The blinking blue GPSV LED indicates that the
Pro Pilot has identified the ARINC vertical tracking data.
 At this time, the display screen will show the vertical
distance to the descent path into the airport. The
screen shown here illustrates that the descent line is
just 420 feet above the aircraft as it intercepts. The
aircraft will command a “bend over” pitch down just
prior to intercept so that it doesn’t overshoot the line.
When the aircraft intercepts the descent line,
 The
GPSV LED will glow steadily.
 The
autopilot V MODE indicator will automatically change to the AS/VS mode (AS/VS LED will
illuminate) and begin the descent.
 The display screen will continue to show the vertical and horizontal tracking accuracy.
In most cases, ATC will assign your intercept altitude well below the glideslope descent line. The aircraft
flight path will be such that the aircraft intercepts the descent path from below the line.
However, the autopilot will allow as much as a 500 foot above the line intercept condition. In this case
the ARINC vertical tracking data will become active when the aircraft is positioned above the descent
path. The autopilot will now command an immediate “bend over” to intercept the descent path.
NOTE: If the aircraft path is more than 500 feet above the descent path the approach will be immediately
terminated, and the autopilot will flash an abort message and enter ALT HLD until the vertical
servo is disengaged.