Description The APP mode produces a non precision approach similar to an ILS approach when using a non localizer
based approach from the data base with FMS selected as the Primary Navaid (LNAV button on
DC).
The Vertical Glide Path (VGP) is anchored at the BOD (Bottom of Descent) —ie 50 ft above the running
threshold— with an angle equal to that specified in the Jeppesen data base at the corresponding
waypoint.
Aircraft axes control is performed via:
• roll attitude for LNAV lateral steering
• collective input for VGP
Engagement
• Arming:.................... Press APP button on Guidance Controller
• VGP mode is armed
• HDG mode is automatically engaged and the present heading held
Conditions for arming VGP mode:
• FMS is selected as Primary Navaid and a published non-Localizer approach is selected as Arrival
in the Active FPL
• FMS is not in DR (Dead Reckoning) mode
• Helicopter is within 30 nm of destination
• Altitude and angle constraint values have not been changed
• If there is an altitude constraint at the FAF (Final Approach Fix), the helicopter must be at the
FAF altitude
• No vertical direct-to the FAF has been executed
NOTE
If APP pushbutton is pressed when Primary Navaid is FMS and VGP is not available, the VGP
UNAVAILABLE message is displayed in the MCDU scratchpad.