Honeywell SPZ-8000 Pilot's Manual page 209

SPZ--8000 Digital Integrated Flight Control System
The altitude preselect mode is automatically armed, as shown in Figure
8--38, when the following conditions exist:
— Selected altitude is more than 250 feet from present altitude
— Vertical speed toward the selected altitude is greater than 1.3
feet/second for 3 seconds
— Autopilot is engaged or a flight director mode is active
— Glideslope is not in capture or track.
Modes of Operation
8-48
Altitude Preselect Mode
Figure 8--38
AD--58159@
A28--1146--055
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