Van's Aircraft HB-YMT, Flight Manual

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Airplane Flight Manual HB-YMT
01/00 Description of the Airplane and its Systems 7–59
7.13 Autopilot
The Trutrak Flight Systems Digiflight II VSGV (AFS Version) is
an advanced 2-axis flight control system. It is capable of
controlling the airplane through most of its envelope with
low speed and high speed protections. It uses GPS ground
track as a primary means of reference for the lateral modes,
with a backup wing leveler in case of loss of GPS signal (from
the Garmin puck). For the vertical functions it relies on
barometric pressures through the pitot/static system. The
autopilot will NO
NO NO NOT TTT directly command trim controls command trim controls command trim controls command trim controls, but
indicates on the display to the pilot in which direction the
aircraft should be trimmed.
CAUTION It is possible, that upon autopilot disconnection, the aircraft
might be in an out of trim state.
A button on each control stick gives direct access to the CWS
CWS CWS CWS
(Control Wheel Steering) (Control Wheel Steering) (Control Wheel Steering) (Control Wheel Steering) and Autopilot disconnect Autopilot disconnect Autopilot disconnect Autopilot disconnect
functions. Pressing the button for longer than 2s will engage
the autopilot with the current track and vertical speed. Upon
release, the autopilot will continue on the last track and
vertical speed.
Pressing the stick button shortly while engaged will cause
the autopilot to disconnect.
Pressing the “EFIS
EFIS EFIS EFIS” button button button button on the autopilot will engage the
autopilot, slaved to the EFIS Flight Director both vertically
and laterally.
The data from the EFIS is received through the AFS
ARINC429 extender box, which is powered by the “Aux Box”
circuit.
For further instructions regarding the operation of the
autopilot, please refer to the Trutrak Digiflight II Operations
manual.