Garmin G1000 Piper PA32 - Manual (Page 325)

190-00692-00 Rev. B Garmin G1000 Pilot’s Guide for Piper PA32 6-45
HAZARD AVOIDANCE
TAWS utilizes terrain and obstacle databases that are referenced to mean sea level (MSL). Using the GPS
position and GPS-MSL altitude, TAWS displays a 2-D picture of the surrounding terrain and obstacles relative
to the position and altitude of the aircraft. Furthermore, 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
manner, TAWS can provide advanced alerts of predicted dangerous terrain conditions. Detailed alert modes
are described later in this section.
BARO-CORRECTED ALTITUDE VERSUS GPS-MSL ALTITUDE
Baro-corrected altitude (or indicated altitude) is derived by adjusting the altimeter setting for local
atmospheric conditions. The most accurate baro-corrected altitude can be achieved by frequently updating
the altimeter setting to the nearest reporting station along the flight path. However, because actual atmosphere
conditions seldom match the standard conditions defined by the International Standard Atmosphere (ISA)
model (where pressure, temperature, and lapse rates have fixed values), it is common for the baro-corrected
altitude (as read from the altimeter) to differ from the GPS-MSL altitude. This variation results in the aircraft’s
true altitude differing from the baro-corrected altitude.
USING TAWS
During G1000 power-up, the terrain/obstacle database versions are displayed along with a disclaimer to the
pilot. At the same time, TAWS self-test begins. One of the following aural messages is generated:
• “TAWS System Test OK”
• “TAWS System Failure”
TAWS information can be displayed on the following pages:
• TAWS Page • AUX - Trip Planning Page
• Navigation Map • Flight Plan Pages
• PFD Inset Map
TAWS can also be displayed on the PFD Inset Map by selecting the INSET Softkey, then the TERRAIN
Softkey. TAWS display may also be deselected from the Inset Map without affecting the display on the MFD
maps.
To display TAWS data on any page other than the TAWS Page, press the MAP Softkey, then press the TERRAIN
Softkey. Terrain and obstacles with heights greater than 200 feet above ground level (AGL) are displayed in
yellow and red (Table 6-7). The G1000 adjusts colors automatically as the aircraft altitude changes.