Garmin Bell 407 GTN User manual

190-01007-J4 Rev. 1 RFMS, Bell 407 GTN GPS/SBAS System
Page 2 of 22 FAA APPROVED
LOG OF REVISIONS
Page
Revision
Number
Date
Number
Description
FAA Approved
1
10/23/2013
All
Complete Supplement
See page 1

RFMS, Bell 407 GTN GPS/SBAS System 190-01007-J4 Rev. 1
FAA APPROVED Page 3 of 22
Table of Contents
SECTION PAGE
GENERAL INFORMATION 5
Garmin GTN Navigators 5
Capabilities 7
Definitions 7
Section 1. LIMITATIONS 8
1.1 Kinds of Operation 8
1.2 Applicable System Software 8
1.3 SD Card 8
1.4 Ground Operations 8
1.5 Terrain Proximity Function (All Units) 8
1.6 HTAWS Function (Optional) 9
1.7 Datalinked Weather Display (Optional) 9
1.8 Traffic Display (Optional) 9
1.9 Flight Planner/Calculator Functions 9
1.10 Glove Use / Covered Fingers 10
1.11 Demo Mode 10
1.12 Telephone Audio 10
Section 2. NORMAL PROCEDURES 11
2.1 Unit Power On 11
2.2 Before Takeoff 11
2.3 Telephone & SMS Text (Optional) 11
2.4 HTAWS INHIBIT 11
Section 3. EMERGENCY / MALFUNCTION PROCEDURES 12
3.1 HTAWS 12
3.2 COM RADIO 12
3.3 AUDIO PANEL 13
3.4 OTHER 13
Section 4. PERFORMANCE 14
Section 5. WEIGHT AND BALANCE 14
SYSTEM DESCRIPTIONS 15
Pilot’s Guide 15
Power 15
Lighting Controls 15
GMA 35 Audio Panel (Optional) 15
TERRAIN PROXIMITY 16
HTAWS 16
Traffic System (Optional) 18
Datalinks (Optional) 19
Databases 19
External Switches 20
Map Orientation 20
Airspace Depiction and Alerts 21
Fuel Planning Page 21
Charts (Optional) 22

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Transponder Control (Optional) 22
Telephone Audio (Optional) 22

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GENERAL INFORMATION
Garmin GTN Navigators
The Garmin GTN navigation system is a GPS system with a Satellite Based
Augmentation System (SBAS), comprised of one or more Garmin TSO-C146c
GTN 625, 635, 650, 725, or 750 navigator(s) and one or more Garmin approved
GPS/SBAS antenna(s).
GTN system functions are shown in Table 1.
GTN 625
GTN 635
GTN 650
GTN 725
GTN 750
GPS SBAS Navigation
X
X
X
X
X
VHF Com Radio, 118.00 to 136.990, MHz, 8.33 or 25 kHz
increments
X
X
X
VHF Nav Radio, 108.00 to 117.95 MHz, 50 kHz increments
X
X
LOC and Glideslope non-precision and precision approach
guidance, 328.6 to 335.4 MHz tuning range
X
X
Moving map including topographic, terrain, aviation, and
geopolitical data
X
X
X
X
X
Display of datalink weather products, SiriusXM, Connext ( all
optional)
X
X
X
X
X
Display of terminal procedures data (optional)
X
X
Display of traffic data
X
X
X
X
X
Display of marker beacon annunciators (optional)
X
X
Remote audio panel control (optional)
X
X
Remote transponder control (optional)
X
X
X
X
X
Remote audio entertainment datalink control (optional
X
X
X
X
X
TSO-C194 HTAWS (optional)
X
X
X
X
X
Supplemental calculators and timers
X
X
X
X
X
Control of GSR 56 Iridium Satellite Phone and SMS Text
(optional)
X
X
X
X
X
Table 1 –GTN Functions
The GPS navigation functions and optional VHF communication and navigation
radio functions are operated by dedicated hard keys, a dual concentric rotary
knob, or the touchscreen.
The GTN requires a reasonable degree of familiarity to avoid becoming too
engrossed at the expense of basic see-and-avoid in VMC. Garmin provides
training tools with the Pilot’s Guide and PC based simulator. Pilots should take
full advantage of these training tools to enhance system familiarization.

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Page 6 of 22 FAA APPROVED
Figure 1 - GTN 750 Control and Display Layout
Figure 2 - GTN 635/650 Control and Display Layout

RFMS, Bell 407 GTN GPS/SBAS System 190-01007-J4 Rev. 1
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Capabilities
The following GTN equipment is installed in this aircraft:
GTN 750
GTN 725
GTN 650
GTN 635
GTN 625
The GTN system and associated navigation interface in this aircraft have the
following capability, in addition to the core GPS navigation and display
capability:
VHF Communication Radio
VHF Navigation
HTAWS
Definitions
The following terminology is used within this document:
GPS: Global Positioning System
GTN: Garmin Touchscreen Navigator
HTAWS: Helicopter Terrain Awareness and Warning System
IFR: Instrument Flight Rules
LOC: Localizer
NOTAM: Notice to Airmen
RMT: Remote
SBAS: Satellite Based Augmentation System
SD: Secure Digital
TAS: Traffic Awareness System
TCAS: Traffic Collision Avoidance System
TFR: Temporary Flight Restriction
TIS: Traffic Information Service
VCO: Voice Call Out
VHF: Very High Frequency
VFR: Visual Flight Rules
VMC: Visual Meteorological Conditions
XFR: Transfer

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Page 8 of 22 FAA APPROVED
Section 1. LIMITATIONS
1.1 Kinds of Operation
This model helicopter shall only be operated under VFR conditions in
accordance with 14 Code of Federal Regulations Part 91 and/or Part 135. This
RFM supplement does not grant approval for IFR operations to aircraft limited
to VFR operations.
1.2 Applicable System Software
Use of this RFMS is limited to the software versions shown in Table 2.
Software Item
Software Version
(or later FAA Approved versions for this STC)
Main SW Version
4.00
Table 2 - Software Versions
The Main software versions are displayed on the start-up page immediately after
power-on. All software versions displayed in Table 2 can be viewed on the
System –System Status page.
1.3 SD Card
The SD card shall be present in the unit at all times.
1.4 Ground Operations
SafeTaxi or Chartview functions shall not be used as the sole basis for ground
maneuvering.
SafeTaxi and Chartview functions do not comply with the requirements of AC
20-159 and are not qualified to be used as an airport moving map display
(AMMD). SafeTaxi and Chartview may be used by the flight crew to orient
themselves on the airport surface to improve flight crew situational awareness
during ground operations.
1.5 Terrain Proximity Function (All Units)
Aircraft maneuvers and navigation shall not be predicated upon the use of the
terrain display.
The terrain display is intended to assist the pilot with maintaining awareness of
the proximity of terrain and obstacles to the rotorcraft. By itself, the terrain
display may not provide either the accuracy or the fidelity on which to base
decisions and plan maneuvers to avoid terrain or obstacles.

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1.6 HTAWS Function (Optional)
HTAWS shall NOT be used for navigation purposes.
HTAWS shall only be inhibited when in visual contact with terrain and when
the pilot can be assured of maintaining clearance from terrain and obstacles.
RP Mode shall only be used when in visual contact with terrain.
External HTAWS annunciators installed in the aircraft shall be fully functional
in order to use the HTAWS system.
The external “HTAWS ALERT ACK” switch shall be used in lieu of the Alert
Acknowledge function under the Terrain page menu to minimize pilot workload
during alert conditions.
NOTE
Terrain Proximity and HTAWS are separate features and
mutually exclusive. If “HTAWS” is shown on the bottom
right of the dedicated terrain page, then HTAWS is installed.
1.7 Datalinked Weather Display (Optional)
This limitation applies to datalinked weather products from SiriusXM via a
GDL 69/69A and Connext via a GSR 56.
Data link weather information shall not be used for maneuvering in, near, or
around areas of hazardous weather.
The indicated data link weather product age shall not be used to determine the
age of the weather information shown by the data link weather product.
Information provided by data link weather products may not accurately depict
current weather conditions. Due to time delays inherent in gathering and
processing weather data for data link transmission, the weather information
shown by the data link weather product may be significantly older than the
indicated weather product age.
Data link services shall not be the sole means used to obtain Temporary Flight
Restriction (TFR) or Notice to Airmen (NOTAM) information. Not all TFRs
and NOTAMS may be available on the GTN.
1.8 Traffic Display (Optional)
The display of traffic is an aid to visual acquisition and shall not be utilized for
aircraft maneuvering.
1.9 Flight Planner/Calculator Functions
The Fuel Planning page shall not be used as a means to determine actual fuel on
board the aircraft.

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1.10 Glove Use / Covered Fingers
No article shall be used to cover fingers used to operate the GTN unless the
Glove Qualification Procedure located in the Pilot’s Guide/Cockpit Reference
Guide has been successfully completed. The Glove Qualification Procedure is
specific to a pilot / glove / GTN 725, 750 or GTN 625, 635, 650 combination.
1.11 Demo Mode
Demo mode shall not be used in flight under any circumstances.
1.12 Telephone Audio
Telephone audio shall not be turned on to the pilot or co-pilot unless a phone
call is active.
Failure to turn off telephone audio when the telephone is not in use may result in
telephone ringer or text message aural notifications being received during
critical phases of flight.

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Section 2. NORMAL PROCEDURES
Refer to the Cockpit Reference Guide or the Pilot’s Guide defined in Systems
Description section of this document for normal operating procedures and a
complete list of system messages and associated flight crew actions. This
includes all GPS operations, VHF communication and navigation, traffic, data
linked weather, HTAWS, and Multi-Function Display information.
2.1 Unit Power On
Database.......................................................... REVIEW EFFECTIVE DATES
Self Test....................................VERIFY OUTPUTS TO NAV INDICATORS
Self Test - HTAWS Remote Annunciator:
HTAWS (Red)....................................................................ILLUMINATED
HTAWS (Yellow)...............................................................ILLUMINATED
HTAWS N/A (Yellow).......................................................ILLUMINATED
AURAL MESSAGE..................................................... VERIFY VOLUME
Self Test - HTAWS Annunciator on G500H(if installed):
HTAWS TEST ...................................................................ILLUMINATED
2.2 Before Takeoff
System Messages and Annunciators............................................CONSIDERED
2.3 Telephone & SMS Text (Optional)
Audio from the GSR 56 Iridium datalink is routed through your aircraft’s audio
panel. The primary indications of an incoming phone call or SMS text are the
visual indications on the GTN.
2.4 HTAWS INHIBIT
The HTAWS functions may be inhibited to prevent alerting, if desired. Refer to
GTN Cockpit Reference Guide for additional information. When HTAWS is
inhibited, all HTAWS aural and visual alerting is suppressed, but VCOs remain
available. HTAWS shall only be inhibited when in visual contact with terrain
and when the pilot can be assured of maintaining clearance from terrain and
obstacles.
To Inhibit HTAWS:
Home Hardkey............................................................................................PRESS
Terrain Button.............................................................................................PRESS
Menu Button...............................................................................................PRESS
HTAWS Inhibit Button....................................................PRESS TO ACTIVATE

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Section 3. EMERGENCY / MALFUNCTION PROCEDURES
3.1 HTAWS
3.1.1 HTAWS WARNING
Red annunciator and aural “TERRAIN”or “OBSTACLE”:
Aircraft Controls.........................................INITIATE ESCAPE MANUEVER
3.1.2 HTAWS CAUTION
Yellow annunciator and aural “TERRAIN”or “OBSTACLE”:
VERIFY THE AIRCRAFT FLIGHT PATH
AND CORRECT, IF REQUIRED.
3.1.3 HTAWS N/A and HTAWS FAIL
If the amber external HTAWS N/A status annunciator is displayed, the system
will no longer provide HTAWS alerting or display relative terrain and obstacle
elevations. The crew must operate the aircraft in a manner to ensure minimum
safe terrain and obstacle separation.
3.2 COM RADIO
3.2.1 LOSS OF COM RADIO TUNING FUNCTIONS
If alternate COM is available:
Communications ........................................................USE ALTERNATE COM
If no alternate COM is available:
GTN VOLUME KNOB.......................PRESS AND HOLD FOR 2 SECONDS
OR
COM Remote Transfer Button ............PRESS AND HOLD FOR 2 SECONDS
NOTE
This procedure will tune the active COM radio to the
emergency frequency, 121.5, regardless of what frequency is
displayed on the GTN. Certain failures of the tuning system
will automatically tune 121.5 without flight crew action.

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3.3 AUDIO PANEL
3.3.1 LOSS OF AUDIO PANEL FUNCTIONS (GMA 35 Only)
Audio Panel Circuit Breaker........................................................................PULL
NOTE
This procedure will force the audio panel into fail safe mode
which provides only the pilot with communications and only
on a single COM radio. If any non GTN 750 COM is
installed, communication will be only on that radio. If only
a GTN 750 is installed in the aircraft, then the pilot will have
only the GTN 750 COM available. No other audio panel
functions including the crew and passenger intercom will
function.
3.4 OTHER
3.4.1 DATA SOURCE - HEADING SOURCE INOPERATIVE OR
CONNECTION TO GTN LOST MESSAGE
Without a heading source to the GTN, the following system limitations will be
imposed:
Map cannot be oriented to Heading Up.
All overlaying traffic data from a TAS/TCAS I cannot be displayed on the
main map display. The flight crew must use the dedicated traffic page on
the GTN system to display TAS/TCAS I traffic data.
3.4.2 DATA SOURCE –PRESSURE ALTITUDE SOURCE
INOPERATIVE OR CONNECTION TO GTN LOST MESSAGE
Without a barometric altitude source to the GTN, the following system
limitations will be imposed:
Automatic leg sequencing of legs requiring an altitude source. The flight
crew must manually sequence altitude legs, as prompted by the system.

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Section 4. PERFORMANCE
No change.
Section 5. WEIGHT AND BALANCE
See current weight and balance data.

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SYSTEM DESCRIPTIONS
Pilot’s Guide
The Garmin GTN 6XX or GTN 7XX Pilot’s Guide, part number and revision
listed below, contain additional information regarding GTN system description,
control and function. The Pilot’s Guides do not need to be immediately available
to the flight crew.
GTN 6XX Pilot’s Guide P/N 190-01004-03 Rev F or later
GTN 7XX Pilot’s Guide P/N 190-01007-03 Rev F or later
Power
Power to the GTN is provided through a circuit breaker labeled GPS or
NAV/GPS. If more than one GPS or NAV is installed then the label will
have a 1 or 2 to designate the unit receiving power.
Power to the optional GTN COM is provided through a circuit breaker
labeled COM. If more than one COM is installed then the label will also
have a number to designate the unit receiving power.
Power to the optional GMA 35 is provided through a circuit breaker labeled
AUDIO.
Lighting Controls
Control of the GTN backlight and bezel may be provided by either the built in
photocell or via the aircraft instrument dimmer switch. For this installation
dimming of the GTN is controlled by:
The GTN photocell.
The aircraft instrument dimmer switch.
If installed, the external HTAWS status annunciator is dimmed via a dedicated
HTAWS bright/dim switch. The HTAWS WARN/CAUTION annunciator can
be operated at two fixed brightness levels as controlled by the aircraft
BRIGHT/DIM switch.
GMA 35 Audio Panel (Optional)
The GTN 725 and 750 can interface to a GMA 35 remotely mounted audio
panel and marker beacon receiver. Controls for listening to various radios,
clearance playback control, and marker beacon are accessed by pressing the
“Audio Panel” button on the GTN display screen. Volume controls for the audio
panel, telephone, and music are accessed by pressing the “Intercom” button on
the GTN display screen.
If an optional GSR 56 is installed, when an incoming phone call is received it is
necessary to turn on the telephone audio to desired recipients. Press the
“Intercom” button on the GTN display screen, press the “Telephone” button,
and then press the buttons for those who will participate in the call. Telephone
volume can be adjusted using the controls on this page. Upon completion of the
call, turn off the telephone audio by pressing the “Intercom” button on the GTN

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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.

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The Obstacle Database contains only KNOWN obstacles and does not contain
ALL existing obstacles. The Obstacle Database does not contain the location of
power line poles or wires.
HTAWS aurals may be selected to be in Male or Female voice. Selecting the
voice gender is accomplished using Audio button under the Systems page.
HTAWS also includes pilot selectable Voice Callouts (VCOs) of helicopter
height above terrain from 500 feet AGL to the surface.
If HTAWS is not installed, then the GTN will provide Terrain Proximity
functions which only provide visual depictions of terrain and obstacles on the
map page but provides no alerting or VCOs.
TERRAIN AND OBSTACLE DEPICTION
Terrain and obstacle elevations relative to aircraft altitude are depicted on the
Terrain page and may also be selected by the pilot for display on the Map page.
HTAWS NORMAL MODE
The GTN will power on with HTAWS in Normal Mode. Normal Mode
provides for separation from terrain and obstacles appropriate for enroute, night,
and operations where the pilot is not in visual contact with terrain.
HTAWS REDUCED PROTECTION MODE
The “RP MODE” menu selection on the terrain page is used to activate the
Reduced Protection (RP) functionality. RP Mode reduces alerting thresholds
and suppresses aural and visual cautions to allow operation in closer proximity
to terrain and obstacles while continuing to provide protection from terrain and
obstacles. An optional “RP MODE” external switch installation on the
instrument panel is allowed to toggle Reduced Protection mode in the same
manner as using the Terrain Menu selection.
HTAWS INHIBIT
The “INHIBIT” menu on the terrain page is used to inhibit visual and aural
HTAWS terrain and obstacle alerts. VCOs will still be provided. HTAWS shall
only be inhibited if the pilot is certain of the ability to maintain separation from
terrain and obstacles.
HTAWS TEST
The “HTAWS TEST” menu selection on the Terrain Page is used to activate a
manual test which verifies proper operation of the aural and visual annunciations
of the system. The aural message “HTAWS System Test, OK” is played if the
system passes the test, if the system fails the test “HTAWS System Failure” is
played. HTAWS test is only available while on the ground.
VOICE CALL OUTS
Voice callouts (VCOs) provide voice annunciation of the aircraft height above
terrain when that altitude is descended through. VCOs may be enabled by the
pilot in 100ft increments from 500 feet above ground level to the surface. If a

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radar altimeter is interfaced with the GTN then VCOs are provided based on
radar altitude and an additional VCO is provided at 50 feet above ground. If no
radar altimeter is interfaced with the GTN then VCOs are provided based on
GPS altitude above terrain and no 50 foot call is available. Selecting the altitude
above ground at which VCOs begin is accomplished using the Audio button
under the Systems page.
ALERT ACKNOWLEGE
The Alert Acknowledge function is used to mute an active HTAWS caution or
when operating in RP Mode to muffle an active HTAWS warning. Muting of a
caution will last for the duration of the caution alert. Muffling of an RP Mode
warning will last 10 seconds at which time the pilot may elect to re-muffle the
alert.
HTAWS ANNUNCIATORS
When HTAWS is installed, HTAWS Mode and Status annunciations are
provided at the lower left corner of the HTAWS enabled GTN unit. In addition,
HTAWS Mode and Alert annunciators external to the GTN will be present.
If an optional G500H system is installed in the helicopter then all HTAWS
mode and status annunciators from the GTN will be provided on the Primary
Flight Display of the G500H.
If no G500H system is installed, then two HTAWS mode and status
annunciators from the GTN will be installed in the eyebrow panel adjacent to
the aircraft annunciator panel. One annunciator provides visual alerts for
HTAWS warning (red) and caution (yellow) conditions. The second
annunciator indicates whether HTAWS protection is being provided by means
of a dual color HTAWS N/A indication. When HTAWS N/A is illuminated in
amber HTAWS protection is not being provided as the result of either a system
failure or loss of a required input. When HTAWS N/A is illuminated in white
HTAWS protection is not being provided as the result of either automatic
inhibiting below 30 knots groundspeed or pilot inhibiting of HTAWS alerting.
Traffic System (Optional)
Traffic may be displayed on the GTN when connected to an approved optional
TCAS I, TAS, or TIS traffic device. These systems are capable of providing
traffic monitoring and alerting to the flight crew. Traffic shown on the display
may or may not have traffic alerting available.
Garmin GTN 6XX or GTN 7XX Cockpit Reference Guide or Garmin GTN
6XX or GTN 7XX Pilot’s Guide provides additional information regarding the
functionality of the traffic device.

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The GTN is configured for the following type of traffic system:
No traffic system is interfaced to the GTN.
A TAS/TCAS I traffic system is interfaced to the GTN.
A TIS traffic system is interfaced to the GTN.
A TCAD traffic system is interfaced to the GTN.
Datalinks (Optional)
The GTN is configured for the following type of datalinks. The Garmin GTN
6XX or GTN 7XX Cockpit Reference Guide or Garmin GTN 6XX or GTN
7XX Pilot’s Guide provides additional information regarding the functionality
of the datalink device.
No datalink is interfaced to the GTN.
A GDL 69/69A Sirius/XM datalink is interfaced to the GTN.
A GSR 56 Iridium datalink is interfaced to the GTN.
Databases
Database versions and effective dates are displayed on the start-up page
immediately after power-on. Database information can also be viewed on the
System –System Status page.
HTAWS terrain databases are regionalized. When operating out of the terrain
coverage area HTAWS protection will be unavailable and will be indicated by
an HTAWS N/A annunciator, blue cross hatching the terrain map, and aural
“HTAWS NOT AVAILABLE” Message. The coverage area for the terrain
database can be determined by the name of the database and the coverage table
provided in the GTN Pilot’s Guide. The Obstacle Database coverage area
includes the United States and Europe.

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External Switches
External switches may be installed and interfaced to the GTN. Table 3 lists the
switches and function they perform:
Switch Label
Description
COM CHNL DWN
Located on the cyclic. Toggles down through the
user com frequencies.
COM CHNL UP
Located on the cyclic. Toggles up through the
user com frequencies.
COM XFER
Located on the cyclic. Transfers the com active /
standby frequencies.
HTAWS ALERT
ACK
Located on the cyclic. Press to mute an active
HTAWS caution when in Normal Mode or
muffle an active warning for 10 seconds when in
RP Mode.
MOT
Located on the instrument panel or center
console. Press to create a user waypoint at the
present position.
PTT
Located on the cyclic. Press and hold to transmit
on the selected COM.
RP MODE
Located on the instrument panel or center
console. Press to turn ON or OFF HTAWS
Reduced Protection Mode. This mode is used for
VFR operations when in visual contact with
terrain.
Table 3 –External Switches
Map Orientation
The Map and Weather Pages on the GTN can be selected by the pilot to be
oriented Heading Up, Track Up, or North Up. When installed in an aircraft with
a heading source the Heading Up orientation will be available and is
recommended for use.