Garmin G1000 Cockpit Reference Manual page 76

SECTION 6 – AUTOMATIC
FLIGHT CONTROL
Changing the Airspeed Reference
The Airspeed Reference (shown in both the AFCS
Status Box and above the Airspeed Indicator) may be
adjusted by:
• Using the NOSE UP/DN Wheel
• Pressing the CWS Button, hand-flying the
aircraft to attain a new Airspeed Reference,
then releasing the CWS Button
Vertical Navigation Modes (VPTH, ALTV)
NOTE: VNV is disabled when parallel track or
Dead Reckoning Mode is active. Refer to the
Navigation section for more information on VNV
flight plans.
NOTE: The Selected Altitude takes precedence
over any other vertical constraints.
Vertical Navigation (VNV) flight control is available for
enroute/terminal cruise and descent operations when VNV
flight planning is available. Conditions for availability
include, but are not limited to:
• The selected navigation source is GPS.
• A VNV flight plan (with at least one altitude-
constrained waypoint) or vertical direct-to is active.
• VNV is enabled (VNV ENBL Softkey pressed on the
MFD).
• Crosstrack error is valid and within certain limits.
• Desired/actual track are valid or track angle error is
within certain limits.
• The VNV Target Altitude of the active waypoint is no
more than 250 ft above the current aircraft altitude.
The flight director may be armed for VNV at any time,
but no target altitudes are captured during a climb. The
Command Bars provide vertical profile guidance based on
specified altitudes (entered manually or loaded from the
6-10
Garmin G1000 Cockpit Reference Guide for the Socata TBM 850
database) at waypoints in the active flight plan or vertical
direct-to. The appropriate VNV flight control modes are
sequenced by the flight director to follow the path defined
by the vertical profile. Upon reaching the last waypoint
in the VNV flight plan, the flight director transitions to
Altitude Hold Mode and cancels any armed VNV modes.
Vertical Path Tracking Mode (VPTH)
NOTE: If another vertical mode key is pressed
while Vertical Path Tracking Mode is selected,
Vertical Path Tracking Mode reverts to armed.
NOTE: Pressing the CWS Button while Vertical
Path Tracking Mode is active does not cancel
the mode. The autopilot guides the aircraft back
to the descent path upon release of the CWS
Button.
When a vertical profile (VNV flight plan) is active and
the VNV Key is pressed, Vertical Path Tracking Mode is
armed in preparation for descent path capture. 'VPTH' (or
'/V' when Glidepath or Glideslope Mode is concurrently
armed) is annunciated in white in addition to previously
armed modes. If applicable, the appropriate altitude
capture mode is armed for capture of the next VNV
Target Altitude (ALTV) or the Selected Altitude (ALTS),
whichever is greater.
Figure 6-11 Vertical Path Tracking Armed Annunciations
Prior to descent path interception, the Selected Altitude
must be set below the current aircraft altitude by at least
75 feet. For the flight director to transition from Altitude
Hold to Vertical Path Tracking Mode, acknowledgment is
required within five minutes of descent path interception
by:
190-00708-00 Rev. A