BendixKing KTA 910 System KTA 970 - Manual (Page 47)

KTA 870/KMH 880 Pilot’s Guide
Rev 2 006-18265-0000
EGPWS Functions and Features
39
GA-EGPWS FUNCTIONS AND FEATURES
AIRCRAFT POSITION
The GA-EGPWS uses Global Positioning System (GPS) information
from either an aircraft-installed GPS receiver, or an internal GPS receiver
contained in the GA-EGPWS computer itself. It is good for the pilot to be
aware of the actual position source being used by the system, as the
internal GPS is not used for navigation of the aircraft.
GPS signals arrive at an antenna on the aircraft and are then processed
by the GA-EGPWS computer to provide both horizontal (lateral) and ver-
tical position (altitude) information. This position in space is then com-
pared to the terrain, obstacle and runway database information con-
tained in the GA-EGPWS computer to produce a “virtual” picture which
can then be displayed to provide Situational Awareness for the pilot.
Other GPS information such as true track, groundspeed, vertical velocity,
N/S and E/W velocity, and signal accuracy measurements are also
processed by the GA-EGPWS computer to provide a complete picture of
not only the aircraft position in three dimensions, but also an excellent
picture of the aircraft’s flight path.
This total package of information is then used to provide the Terrain
Display for the pilot, and to provide alerting and warning functionality to
protect the pilot and passengers from possible conflicts with terrain,
known obstacles, and other scenarios associated with the dangers of
Controlled Flight Into Terrain (CFIT).