Honeywell SPZ-8000 Pilot's Manual page 212

Vertical Path (VPTH) Mode -- VPTH mode is used to fly a fixed
D
flightpath angle to a vertical waypoint during descent. The VPTH
mode engages whenever the FMS initiates a path descent, which
can occur while in VFLC or VALT modes. When the mode captures,
VPTH is displayed on the EADI. The mode annunciator flashes for
5 seconds to indicate the transition from arm to capture.
displayed on the advisory display in reverse video for 5 seconds,
then changes to normal text. VPTH mode is cancelled by VASL
mode capture. To fly the VPTH mode, the following parameters are
entered on the FMS control display unit (CDU):
— The desired aircraft altitude
— The distance TO/FROM the waypoint
— An angle of descent (if the pilot wants to fly a particular flightpath
angle).
All of the other normally entered VNAV parameters, such as station
elevation and DME distance to station are automatically input
through the navigation computer, or they are called up from the FMS
database.
For a complete description of VNAV operation, refer to the
applicable Flight Management System Pilot's Operating Manual.
NOTE: VNAV must be disengaged below 400 feet AGL.
A28--1146--055
REV 2
SPZ--8000 Digital Integrated Flight Control System
VPTH is
Modes of Operation
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