User Guide
Garmin G1000 Pilot’s Guide for the Columbia 350/400
190-00552-00 Rev. A6-42
HAZARD AVOIDANCE
TERRAIN AWARENESS & WARNING SYSTEM (TAWS) CLASS B (OPTIONAL)
NOTE: TAWS data is not displayed when the aircraft latitude is greater than 75 degrees north or 60 degrees
south.
The Terrain Awareness and Warning System (TAWS) is an optional feature to increase situational awareness
and aid in reducing Controlled Flight Into Terrain (CFIT). It provides look-ahead capability that gives automatic
aural and visual warnings of potential terrain hazards above and beneath the aircraft. TAWS requires the
following components to operate properly:
• Valid 3D GPS position
• Valid Terrain/Obstacle Database
The G1000 GPS provides TAWS with horizontal position and altitude. GPS altitude is derived from satellite
position. GPS altitude is then converted to a mean sea level (MSL)–based altitude (GPS–MSL Altitude) and
is used to determine terrain and obstacle proximity and TAWS alerts. GPS-MSL Altitude accuracy is affected
by satellite geometry but is not subject to variations in pressure and temperature that normally affect pressure
altitude sensors. GPS–MSL Altitude does not require local altimeter settings to determine MSL Altitude. GPS
Altitude is a reliable MSL altitude source to calculate terrain and obstacle location.
TAWS uses terrain and obstacle databases that are referenced to mean sea level. Using the GPS position
and altitude, TAWS portrays a 2D picture of the surrounding terrain and obstacles relative to the position and
altitude of the aircraft. The GPS position and GPS-MSL Altitude are used to calculate and predict the aircraft’s
flight path in relation to the surrounding terrain and obstacles. In this way, TAWS can provide the pilot with
advance alerts of predicted dangerous terrain and obstacle conditions.
Terrain elevation is shown relative to the aircraft altitude in Figure 6-48. Terrain and obstacles that are above
the aircraft or less than 100 feet below the aircraft altitude are shown in red. Those between 100 feet and
1000 feet below the aircraft altitude are shown in yellow. Terrain and obstacles lower than 1000 feet below the
aircraft altitude are shown in black
.
Figure 6-48 Terrain Proximity Indications