display screen, then pressing the "Telephone" button, and then turning off each
participant. Telephone volume settings control both the in call volume as well
as the ringer volume.
The GMA 35 can operate in split mode which allows the pilot to communicate
on one COM while the co-pilot simultaneously communicates on a second
COM. When split mode is activated intercom distribution between pilot, copilot
and passengers is turned off. Upon exiting split mode intercom distribution is
restored to the settings active prior to entering split mode.
TERRAIN PROXIMITY
Terrain Proximity refers to the display of terrain information and comprises of a
2-D picture of the surrounding terrain and obstacles relative to the position and
altitude of the rotorcraft, however it does not provide any alerts.
Relative terrain elevation is depicted using a five color scale in which terrain
that is at or above the helicopter's current altitude is depicted in orange and red
while terrain within 250 feet of the helicopter's current altitude is shown in
yellow.
Obstacles are depicted using a three color scale in which obstacles whose top is
at or above the helicopter's current altitude are shown in red while obstacles
within 250 feet of the helicopter's current altitude are shown in yellow.
The terrain page scale depicts the terrain scale but does not depict the obstacle
scale.
NOTE
Terrain Proximity and HTAWS are separate features. If "HTAWS"
is shown on the bottom right of the dedicated terrain page, then
HTAWS is installed.
HTAWS
The GTN can include an optional Helicopter Terrain Awareness and Warning
System (HTAWS) which includes visual depictions of terrain and obstacles
relative to helicopter altitude as well as visual and aural alerts if terrain or
obstacles are a threat to the safe flight of the helicopter.
This installation includes Terrain Proximity. No aural or visual alerts for
terrain or obstacles are provided.
This installation includes HTAWS. Aural and visual alerts will be provided.
HTAWS is an alerting system. The system does NOT guarantee successful
recovery from a conflict due to factors such as pilot response, aircraft
performance, and database limitations. No standardized recovery technique is
defined as recovery maneuvers may vary. HTAWS protection is provided at
groundspeeds above 30 knots.
190-01007-J4 Rev. 1
RFMS, Bell 407 GTN GPS/SBAS System
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