The VDP location is defined by:
.
Distance from a VOR-DME or LOC-DME;
or,
.
Time from the FAF.
The VDP should be considered as the last point from which a stabilized visual descent to the runway can be conducted.
Flying Constant-Angle Non-Precision Approaches
Page 2
Benefits of a Constant-Angle Final Approach
Step-down approaches are based solely on an obstacle-clearance profile; step-down approaches are not optimized for modern commercial jetliners.
Flying a constant-angle approach profile:
.
Provides a more stabilized flight path;
.
Reduces the workload during this critical flight phase; and,
.
Eliminates the risk of error in step-down distances / altitudes and the need for a level-off at the MDA(H).
This reduces the risk of CFIT.
Figure 3
Constant-angle Final Approach
Strategies and Options
Planning a non-precision or RNAV (aRea NAVigation) approach requires defining strategies and options for:
. Lateral guidance :
. use of selected modes (selected heading mode and localizer mode); or,
. use of FMS lateral navigation (NAV mode), until LOC interception or down to MDA(H).
. Vertical guidance :
. use of selected modes (altitude hold mode and V/S mode); or,
. use of FMS vertical navigation down to the FAF (or beyond, as applicable, in accordance with the FCOM).
. Final descent from FAF (or final descent fix):
. use of a step-down descent with level off at MDA(H); or,
. use of a continuous constant-angle descent with decision before or when reaching MDA(H).
Notes :
The requirement to make the decision before or when reaching the MDA(H) – i.e. the allowance to descend below the MDA(H) during the go-around maneuver (dip thru) – depends upon the applicable operational regulation.
On a constant-angle non-precision approach, the MDA(H) may be considered as a DA(H) only if the approach has been surveyed and approved by the state navigation agency and/or operational authorities.
. Use of inertial flight path vector (as available), with or without the autopilot (AP) engaged.
Flying Constant-Angle Non-Precision Approaches
Page 3
AIRBUS INDUSTRIE
Flight Operations Support
A non-precision approach may be conducted using either:
.
Lateral navigation guidance, with monitoring of raw data;
or,
.
Raw data only;
or,
.
Raw data supported by the use of the flight path vector (as available).
A non-precision approach may be conducted with the AP engaged:
.
Using FMS guidance with:
. lateral navigation until LOC interception or down to the MDA(H); and,
. vertical navigation down to the FAF (or beyond, as applicable in accordance with the FCOM), then using vertical speed mode down to the MDA(H); or,
. Using selected guidance: heading mode and altitude hold or vertical speed modes, after leaving the IAF and down to the MDA(H).
The autothrottle/autothrust system should be engaged, in the speed mode.
CFIT Awareness
During the final descent to the MDA(H), PF and PNF should monitor the vertical flight path and lateral flight path, and should not descend to the next step-down altitude before reaching the associated descent fix (DME distance or other reference).
In IMC or at night, flight crews should respond immediately to any GPWS or EGPWS / TAWS warning.
Descending Below MDA
During a non-precision approach the PF is engaged in either handflying the aircraft or supervising the AP operation, the PNF is in charge of acquiring and announcing the visual references.
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