
Climb-out/Enroute
3-5
ALTITUDE HOLD (ALT) MODE
Altitude Hold mode is entered by pressing the “ALT” button on the
autopilot control panel. The system will light up the control panel
button in green, sync the altitude bug on the altimeter to the
nearest 10 feet to current altitude (Avidyne PFD) or current
altitude (Aspen PFD) and turn it solid, and hold the altitude at the
time of mode entry.
If the barometric setting is subsequently adjusted, the airplane will
automatically climb or descend as required to reacquire the
selected altitude.
If the altitude bug is moved more than 50’ away from the holding
altitude, it will turn hollow. The autopilot does not command an
aircraft altitude change at this point and it provides a means for a
new future altitude target to be preset.
The only place to set the Altitude bug is via the PFD.
The autopilot modes annunciator indication is green “
ALT
”.
INDICATED AIRSPEED (IAS) HOLD MODE
Indicated Airspeed Hold mode is entered by pressing the “IAS”
button on the autopilot control panel. The system will light up the
control panel button in green, and adjust the aircraft pitch as
required to achieve the bugged indicated airspeed target and turn
the IAS bug solid. If already in IAS mode, any subsequent
adjustments to the IAS bug sets a new IAS target for the system
and aircraft pitch is automatically adjusted to achieve that new
IAS target.
In aircraft equipped with pitch trim only (no separate pitch servo),
this mode is still functional but may feel less precise than those
aircraft that also have a pitch servo. In these cases, the aircraft
IAS may vary by as much as 5 knots around the target IAS as the
trim system works to hold the target IAS.
The minimum settable IAS bug is V
so
and the maximum settable
IAS bug is V
ne
.
The primary location to set the IAS bug is via the dedicated IAS
knob on the autopilot control panel. The knob has a push-to-sync
capability that will sync the target IAS to the current aircraft IAS.
Change 3