Technical data

Product Specification
HIF-2121/R5 CAGE CODE: 97896 SCALE: NONE SIZE: A DWG NO: 965-1176-601 REV: B SHEET 107
Installations that use a cockpit selection switch for each display may use these outputs to directly control relays that make the
switch between weather and EGPWD. The EGPWS will read each connected cockpit selection switch and output the
corresponding selection. The EGPWS may also be optionally configured to pop-up the terrain display when an EGPWS alert
is detected thereby overriding the crew selections.
Systems with Multi-function Displays (MFD) such as an EFIS will prefer to control Wx/EGPWD selection from the MFD.
When the MKVIII EGPWS is configured for this type of display, these discrete outputs serve as pop-up discretes for each
display. These systems may then optionally include the EGPWS alert pop-up discrete in their internal selection logic to
override the crew selection during a terrain threat.
6.9.4.2.2 EGPWD Status
EGPWD status data is available on an ARINC-429 broadcast output bus. This data includes the current EGPWD status,
range scale selections, EGPWD alert pop-up discrete status, and a 6-character status message for use by external multi-
function displays such as an EFIS (see section 6.7.4.5).