Radio Altimeter System - Honeywell SPZ-8000 Pilot's Manual

The navigation computer can interface with three long--range sensors
through ARINC 429 buses. The interface to the air data, MFD, EFIS,
and DIFCS is over the ASCB. The interconnect to the IRS is through
a separate data bus for position information and ASCB for heading
data. Flight plans are also transferred between navigation computers
over the ASCB, while the link to the CDU is over an RS--422 private--line
interface. The navigation computer gives high--accuracy, long--range
navigation by connecting to the IRS, GPS, VLF/omega sensors, and
VOR/DME. With links to the on--board navigation sensors, the
navigation computer computes an FMS position based on a blend of the
sensors. The FMS does not directly display navigation maps on the
CDU. However, the FMS is the source of map data for other cockpit
displays such as EFIS or MFD. An internal navigation database is the
source of the displayed map data. A large portion of the navigation
database is subject to updating on a 28--day interval. The data loader
is used for this purpose.
The navigation part of the FMS is considered an area navigation
(RNAV) system. This system outputs navigation information that is
relative to a geographic point. The crew can define a route from the
aircraft's present position to any point in the world using the navigation
management software. The system outputs advisory information and
steering signals that the pilot or DIFCS uses to steer the aircraft along
the desired route. Routes are defined from the aircraft present position
to a destination waypoint through a direct great circle route or through
a series of great circle legs connected by intermediate waypoints.

RADIO ALTIMETER SYSTEM

The radio altimeter system consists of the following components:
Radio altimeter receiver/transmitter
D
Antennas (not supplied by Honeywell).
D
The radio altimeter system displays the following:
An absolute altitude from 0 to 2500 feet
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Decision height (DH) selection
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Failure annunciator
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Internal self--test information.
D
A28--1146--055
REV 2
SPZ--8000 Digital Integrated Flight Control System
System Description
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