Garmin GPS 500, Installation Manual

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Page 4-24 500 SERIES INSTALLATION MANUAL
Rev Q 190-00181-02
4.11 TERRAIN AWARNESS AND WARNING SYSTEM (TAWS) AND
TERRAIN
The terms “TAWS” and “TERRAIN” are used to identify two different configurations of 500 Series unit
Main Sub-System. The “TAWS” configuration complies with the Terrain Awareness and Warning System
(TAWS) requirements of TSO-C151b for Class B, whereas the “TERRAIN” configuration provides a
subset of the functionality of “TAWS”.
The following table identifies the high-level differences between TAWS, TERRAIN, and those units with
neither (None):
Function TAWS TERRAIN None
TSO-C151b Class B Certified Yes No No
TAWS/TERRAIN Display
( Shows terrain elevations relative to the aircraft )
Yes Yes No
Visual Alerting
( Includes popup alerting )
Yes Yes No
Aural Alerting Yes No No
External Visual Alerting Capability Yes No No
Reduced Terrain Clearance (RTC) Avoidance
( Forward Looking Terrain Avoidance (FLTA) sub-
function )
Yes Yes No
Imminent Terrain Impact Avoidance
( Forward Looking Terrain Avoidance (FLTA) sub-
function )
Yes Yes No
Premature Descent Alert (PDA) Yes Yes No
Excessive Rates of Descent Alert
( Ground Proximity Warning System (GPWS) Alerting
sub-function )
Yes No No
Negative Climb Rate/Altitude Loss After Takeoff
( Ground Proximity Warning System (GPWS) Alerting
sub-function )
Yes No No
“Five Hundred” Voice Callout
( Ground Proximity Warning System (GPWS) Alerting
sub-function )
Yes No No
Inhibit Capability
( Inhibits FLTA and PDA visual and aural alerting )
Yes Yes No
TAWS Test System Capability Yes No No
Worldwide Terrain Database Yes Yes No
Airport Layer Database Yes Yes No
Obstacle Database Yes Yes No
500 Series TERRAIN functionality is a subset of the TAWS functionality and has been certified as a non-
TSO-function. As such, a subset of the TSO-C151b specification is used as the requirement basis.
500 Series TERRAIN and TAWS functionality is not designed nor approved for use in helicopters.