Page 1 GNC 420(A) Pilot’s Guide and Reference...
Page 3 Revision Date of Revision 7/99 8/00 5/03 8/06 9/06 2/07 10/07 05/08 08/08 12/09 190-00140-20 Rev. K Description Initial Release Revised and Redrawn Added FDE Section, update for SW 4.0 Changed to 8 inch x 8.5 inch format. Added TERRAIN, TIS, Weather interface info, and misc.
Page 4 Garmin®, AutoLocate®, and PhaseTrac12® are registered trademarks of Garmin Ltd. or its subsidiaries and may not be used without the express permission of Garmin. GDL™, GNC™, GTX™, and Spell’N’Find™ are trademarks of Garmin Ltd. or its subsidiaries and may not be used without the express permission of Garmin.
Page 5: Table Of Contents
SECTION 1: INTRODUCTION ... 1-1 1.1 Accessories and Packing List ... 1-1 1.2 Key and Knob Functions ... 1-2 1.3 Takeoff Tour ... 1-5 SECTION 2: COM ... 2-1 2.1 Communicating Using the GNC 420 ... 2-1 SECTION 3: NAV PAGES ...
Page 6 Terrain data is obtained from third party sources. Garmin is not able to independently verify the accuracy of the terrain data.
Page 7 CAUTION: The Garmin GNC 420 does not contain any user-serviceable parts. repairs should only be made by an authorized Garmin service center. Unauthorized repairs or modifications could void both the warranty and the pilot’s authority to operate this device under Faa/FCC regulations.
Page 8 Center; and 90 days for factory repaired or newly-overhauled products exchanged at Garmin in lieu of repair. Within the applicable period, Garmin will, at its sole option, repair or replace any components that fail in normal use. Such repairs or replacement will be made at no charge to the customer for parts or labor, provided that the customer shall be responsible for any transportation cost.
Page 9: Section 1: Introduction
• Warranty Registration Card • GNC 420 Simulator CD-ROM 190-00140-20 Rev. K The Garmin dealer installs and configures the GNC 420. The GNC 420 is secured in the installation rack with the proper wiring connections. A Garmin dealer can answer...
Page 10: Key And Knob Functions
SECTION 1 INTRODUCTION 1.2 KEy AND KNOB FUNCTIONS The GNC 420 is designed to make operation as simple as possible. The key and knob descriptions (Figure 1-1) provide a general overview of the primary function(s) for each key and knob. The takeoff tour (Section 1.3) is intended to provide a brief overview of the primary functions of the GNC 420.
Page 11 Left-hand Keys and Knobs (1) COM Power/Volume Knob – Controls unit power and communications radio volume. Press momentarily to disable automatic squelch control. (2) COM Flip-flop Key – Used to swap the active and standby COM frequencies. Press and hold to select emergency channel (121.500 MHz).
Page 12 SECTION 1 INTRODUCTION NOTe: Data is entered using the large and small right knobs (Figure 1-2). experiment with them to become efficient at entering data. This will greatly reduce the amount of time spent operating the GNC 420 in flight. Figure 1-2 Blank Direct-to Page NOTe: When the GNC 420 displays a list of information that is too long for the display...
Page 13: Takeoff Tour
Service staff is available during normal business hours (U.S. Central time zone) at the phone and fax numbers listed on page ii. Garmin can also be reached by mail (page ii) or at our website address, www.garmin.com. Powering up the GNC 420 The GNC 420’...
Page 14 SECTION 1 INTRODUCTION The Database Versions Page (Figure 1-5) appears next, which shows the current database information on the NavData Card and Terrain Data cards. Database information highlighted in yellow indicates the database is not within its effective dates. The NavData database is updated every 28 days and must be current for approved instrument approach operations.
Page 15 Figure 1-7 Fuel Flow Selected The Instrument Panel Self-test Page includes selections to set fuel on board (FOB) to full capacity and access the Checklists Page. This allows the pilot to quickly set fuel to full limits and display any checklists that have been entered, such as start up or takeoff checklists.
Page 16 Returning to the previous page after viewing a message: Press the MSG Key again. NOTe: The GNC 420 utilizes certain software algorithms to ensure reliable GPS receiver operation. receiver autonomous integrity Monitoring (raiM) and Fault Detection and exclusion (FDe) are two examples. These features allow navigation during Oceanic/remote legs of a flight using the GNC 420.
Page 17 Selecting COM Frequencies While the GNC 420 is acquiring a position, take a minute to dial in the active and standby frequencies to be used for the first phase of the flight. The GNC 420’ s display (Figure 1-12) is divided into separate windows (or screen areas), including a COM Window, data field (distance), and the GPS Window (the right side of the display).
Page 18 SECTION 1 INTRODUCTION Page Groups Page Groups NAV Group WPT Group AUX Group NRST Group see Section 3 see Section 7 see Section 9 Table 1-1 Page Groups The bottom right corner of the screen (Figure 1-14) indicates which page group (Table 1-1) is currently being displayed (NAV, WPT, AUX, or NRST), the number of pages available within that group (indicated by square icons), and the placement of the current page within that...
Page 19 Map Page After the GNC 420 acquires satellites and computes a position, the Map Page (Figure 1-15) appears automatically. Map Display Desired Track Map Range Present Position Figure 1-15 Map Page The Map Page displays the present position (using an airplane symbol) relative to nearby airports, VORs, NDBs, intersections, user waypoints, and airspace boundaries.
Page 20 SECTION 1 INTRODUCTION Press the ENT Key to confirm the identifier. The ‘Activate?’ function field is highlighted (Figure 1-17). Figure 1-17 ‘Activate?’ Highlighted Press the ENT Key to activate a direct-to course to the selected destination. Once a direct-to destination is selected, press and hold the CLR Key to display the Default NAV Page.
Page 21 NAV/COM Page From the Default NAV Page, turn the small right knob until the NAV/COM Page (Figure 1-21) is displayed. Departure, Enroute, or Frequency List Arrival Airport Frequency Type Figure 1-21 NAV/COM Page The NAV/COM Page displays the available frequencies (communications and navigation) for the departure airport, any enroute airports which are included in the flight plan, and the final destination airport.
Page 22 SECTION 1 INTRODUCTION IFR Procedures Once the direct-to or flight plan is confirmed, the whole range of instrument procedures is available to the pilot. Departures (SIDs), arrivals (STARs), and non-precision and precision approaches are stored within the NavData Card and are available using the PROC (procedures) Key. Displaying the Procedures Page: Press the PROC Key (Figure 1-23).
Page 23 Nearest (NRST) Pages The NRST Page Group provides detailed information on the nine nearest airports, VORs, NDBs, intersections, and user-created waypoints within 200 nm of the current position. In addition, pages are also provided to display the five nearest center (ARTCC/FIR) and Flight Service Station (FSS) points of communication, plus alert the pilot to any nearby special-use or controlled airspaces.
Page 24 SECTION 1 INTRODUCTION Viewing additional information for a nearby airport: Press the small right knob to activate the cursor. Turn the large right knob to select the desired airport from the list. Press the ENT Key to display waypoint (WPT) information pages for the selected airport (Figure 1-27).
Page 25 Nearest (NRST) Airspace Page The last page in the NRST Page Group, the Nearest Airspace Page (Figure 1-29), provides information for up to nine controlled or special-use airspaces near or in the flight path. Airspace information appears on this page based on the same criteria used for airspace alert messages: •...
Page 26 SECTION 1 INTRODUCTION Flight Plans (FPL) The GNC 420 lets the pilot create up to 20 flight plans, with up to 31 waypoints in each flight plan. Flight plans are created, edited, and activated using the FPL Key. The FPL Page Group includes two pages: the Active Flight Plan Page and the Flight Plan Catalog Page (Figures 1-31 and 1-32).
Page 27 Repeat steps 5 and 6 until all waypoints for the flight plan have been entered (Figure 1-34). Figure 1-34 Enter Flight Plan Waypoints Once the flight plan is created, it may be activated from the Flight Plan Catalog Page Menu. Activating the flight plan places it into ‘flight plan 00’...
Page 28 SECTION 1 INTRODUCTION Blank Page 1-20 GNC 420(A) Pilot’s Guide and Reference 190-00140-20 Rev. K...
Page 29: Section 2: Com
SECTION 2: COM 2.1 COMMUNICATING USING THE GNC 420 The GNC 420 features a digitally-tuned VHF COM radio that provides a seamless transition from communication to navigation, bringing the two most important functions in flying together in one panel-mounted unit. The GNC 420’...
Page 30 SECTION 2 While receiving a station, an ‘RX’ indication (Figure 2-1) appears in the upper right corner of the COM Window to the immediate right of ‘COM’. A ‘TX’ indication appears at this location when transmitting (Figure 2-2). ‘TX’ Transmit Indication Figure 2-2 ‘TX’...
Page 31 Auto-Tuning The GNC 420’ s auto-tune feature allows the pilot to quickly select any database frequency in the GPS Window as the standby frequency. Any COM frequency displayed in the GPS Window can be transferred to the standby COM frequency field, with a minimum of keystrokes required.
Page 32 SECTION 2 Selecting a COM frequency for a nearby flight service station (FSS) or center (ARTCC): Turn the large right knob to select the NRST Page Group. Turn the small right knob to select the Nearest Center or Nearest Flight Service Page (Figure 2-7).
Page 33 Selecting a COM frequency for any airport in the database: Turn the large right knob to select the WPT Page Group. Turn the small right knob to select the Airport Frequencies Page (Figure 2-9). Figure 2-9 Airport Frequencies Page Press the small right knob to place the cursor on the airport identifier field.
Page 34 SECTION 2 Stuck Microphone As mentioned previously in this section, when the GNC 420 is transmitting, a ‘TX’ indication appears in the COM Window. If the microphone key is stuck, or accidentally left in the on position, or the microphone continues to transmit after the key is released;...
Page 35: Section 3: Nav Pages
SECTION 3: NAV PAGES 3.1 MAIN PAGE GROUPS The GNC 420’ s main pages are divided into four separate page groups: NAV, WPT, AUX, and NRST (Table 3-1). Each page group is comprised of multiple pages. The page groups are selected using the large right knob. The individual pages are selected using the small right knob.
Page 36: Nav
SECTION 3 NAV PAGES 3.2 NAV PAGE GROUP The NAV Page Group includes seven pages (Figure 3-2). While viewing any NAV page, turn the small right knob to select a different NAV page. The pilot may find this selection process convenient to cycle between the Default NAV Page and the Map Page, two of the most frequently used pages.
Page 37 NOTe: The GNC 420 always navigates TO a waypoint unless the OBS switch is set (preventing automatic waypoint sequencing), or the aircraft has passed the last waypoint in the flight plan. Directly below the CDI appears the active leg of the flight plan, or the direct-to destination when using the Direct-to Key.
Page 38 SECTION 3 NAV PAGES Selecting a different data item for any data field: Starting with the Default NAV Page, press the MENU Key to display the Default NAV Page Menu (Figure 3-4). Figure 3-4 Default NAV Page Menu The ‘Change Fields?’ option is already highlighted, so press the ENT Key to select this option.
Page 39: Map Page
A ‘Crossfill?’ option is also provided for the Default NAV Page. This option transfers a direct-to destination or flight plan to a second Garmin 400/500-series unit. See Section 9.2, Flight Planning: Crossfill for additional details on using the crossfill option.
Page 40 SECTION 3 NAV PAGES The symbols in Table 3-3 are used to depict the various airports and NAVAIDs on the Map Page. Symbol Description Airport with hard surface runway(s); (primary runway shown) Airport with soft surface runway(s) only Private Airfield Heliport VOR/DME Localizer...
Page 41 The ‘Setup Map?’ option (described in Section 3.4) allows the pilot to define the maximum range at which each map feature appears. This provides the pilot with complete control to minimize screen clutter. The pilot can also quickly remove items from the map using the CLR Key.
Page 42 SECTION 3 NAV PAGES When the target pointer is placed on an object, the name of that object is highlighted (even if the name wasn’t originally displayed on the map). This feature applies to airports, NAVAIDs, user-created waypoints, roads, lakes, rivers, almost everything displayed on the map except route lines.
Page 43 Airspace Information on the Map When a special-use or controlled airspace boundary appears on the Map Display, the pilot can quickly retrieve information (such as floor/ceiling limits and controlling agency) directly from the map. Viewing airspace information for an on- screen special-use or controlled airspace: Use the panning function (‘Map Panning’...
Page 44 SECTION 3 NAV PAGES Map Setup Many of the GNC 420’ s functions are menu driven. Each of the main pages has an options menu, allowing customization of the page to the pilot’ s preferences and/or selection of special features which specifically relate to that page.
Page 45 Changing map orientation: From the Map Page Menu, turn the large right knob to highlight ‘Setup Map?’ (Figure 3-16) and press the ENT Key. Turn the small right knob to select ‘Map’ (Figure 3-17) and press the ENT Key. Figure 3-17 Map Setup Window Turn the large right knob to highlight the ‘Orientation’...
Page 46 SECTION 3 NAV PAGES Automatic Zoom The automatic zoom feature automatically adjusts the map range from 2000 nm through each lower range, stopping at 1.0 nm when approaching the destination waypoint. Enabling/disabling automatic zoom: From the Map Page Menu, turn the large right knob to highlight ‘Setup Map?’...
Page 47 Displaying airspace boundaries, highways, roads, railroad lines, track log data, active flight plan course lines, and lat/long grid lines: From the Map Page Menu, turn the large right knob to highlight ‘Setup Map?’ and press the ENT Key. Turn the small right knob to select the appropriate group name (per Table 3-2) and press the ENT Key.
Page 48 SECTION 3 NAV PAGES Turning the data fields off/on: Turn the large right knob to highlight ‘Data Fields Off?’ (or ‘Data Fields On?’) and press the ENT Key. Selecting Desired On-Screen Data ‘Change Fields?’ allows the pilot to choose the data displayed on the four user-selectable data fields along the right-hand side of the Map Page.
Page 49: Terrain Page
3.5 TERRAIN PAGE NOTe: The TerraiN Page does not appear on GNC 420 units that are not properly equipped with or configured for TerraiN. See Section 9 for a full description of TerraiN functions. TERRAIN Page To display the TERRAIN Page, select the NAV Page Group and turn the small right knob until the TERRAIN Page is displayed (Figure 3-26 and 3-27).
Page 50 SECTION 3 NAV PAGES To display a 360˚ view: Select the TERRAIN Page and press the MENU Key. Select ‘View 360˚?’ (Figure 3-28). Figure 3-28 TERRAIN Page Menu Press the ENT Key. To switch back to a 120˚ view, repeat step 1, select ‘View 120˚?, and press the ENT Key.
Page 51: Inhibit Mode
Inhibit Mode TERRAIN has an inhibit mode that deactivates the FLTA/PDA visual alerts. Pilots should use discretion when inhibiting TERRAIN and always remember to enable the system when appropriate. See Section 10.3 for more information on TERRAIN alerts. To inhibit TERRAIN: Select the TERRAIN Page and press the MENU Key.
Page 52: Nav/Com Page
SECTION 3 NAV PAGES 3.6 NAV/COM PAGE The NAV/COM (navigation communications) Page (Figure 3-34) provides a list of the airport communication and navigation frequencies at the departure, enroute, and arrival airports. The NAV/COM Page makes selection of the frequencies needed along the flight plan quick and convenient.
Page 53 Scrolling through the list of frequencies: Activate the cursor, if not already active, by pressing the small right knob. Turn the large right knob to move the cursor through the list of frequencies. If there are more frequencies in the list than can be displayed on the screen, a scroll bar along the right-hand side of the screen (Figure 3-36) indicates which part of the list is currently being...
Page 54: Position Page
SECTION 3 NAV PAGES 3.7 POSITION PAGE The Position Page displays the present position (by default, in latitude and longitude) and altitude. The Position Page (Figure 3-39) also displays the current track, ground speed, time, and a reference waypoint field. These fields are user-selectable to configure the page to the pilot’...
Page 55 Press the ENT Key to select the desired data item and return to the Position Page. Press the small right knob momentarily to remove the cursor from the page. The Position Page also features a reference waypoint field, located at the bottom of the page, to indicate the bearing and distance to/from a selected waypoint.
Page 56 SECTION 3 NAV PAGES Press the ENT Key to select the desired type and return to the Position Page. To select between ‘bearing FROM’ or ‘bearing TO’ to the reference waypoint, turn the small right knob to select the desired bearing reference (Figure 3-45) and press the ENT Key.
Page 57: Satellite Status Page
Position of Current Page within Current Page Group 190-00140-20 Rev. K As the GPS receiver locks onto satellites, a signal strength bar appears for each satellite in view, with the appropriate satellite number (01-32) underneath each bar. The status of satellite reception is shown as follows: •...
Page 58 (Figure 3-47) also displays the messages listed in Table 3-5 under the appropriate conditions. The GPS receiver is searching the sky for ANY visible satellites. The Searching Sky pilot is informed of this status with a ‘Searching the Sky’ message.
Page 59: Vertical Navigation Page
3.9 VERTICAL NAVIGATION PAGE The GNC 420’ s Vertical Navigation Page (the last NAV page, see Figure 3-49) allows the pilot to create a three-dimensional profile which guides the pilot from the present position and altitude to a final (target) altitude at a specified location.
Page 60 SECTION 3 NAV PAGES Turn the small right knob to select ‘Above Wpt’ (AGL) or ‘MSL’, (Figure 3-52) and press the ENT Key. ‘Above Wpt’ uses the altitude of a destination airport as stored in the Jeppesen NavData Card. ‘MSL’ lets the pilot set a specific target altitude for any waypoint category: airport, VOR, NDB, intersection, or user waypoint.
Page 61 With the profile set, the vertical speed required (VSR) is displayed on the Vertical Navigation Page. Expect the following to occur when using the vertical navigation feature: • At one minute prior to reaching the initial descent point, a message ‘Approaching VNAV Profile’ occurs.
Page 62 SECTION 3 NAV PAGES Blank Page 3-28 GNC 420(A) Pilot’s Guide and Reference 190-00140-20 Rev. K...
Page 63: Section 4: Direct-To Navigation
SECTION 4: DIRECT-TO NAVIGATION 4.1 OVERVIEW The GNC 420’ s direct-to function provides a quick method of setting a course to a destination waypoint. Once a direct-to is activated, the GNC 420 establishes a point-to-point course line (great circle) from the present position to the selected direct-to destination.
Page 64 SECTION 4 DIRECT-TO NAVIGATION Selecting a Destination by Facility Name or City In addition to selecting a destination by identifier, the Select Direct-to Waypoint Page (Figure 4-4) also allows the pilot to select airports, VORs, and NDBs by facility name or city location.
Page 65 Selecting a direct-to destination from the active flight plan: Press the Direct-to Key. The Select Direct-to Waypoint Page appears, with the waypoint identifier field highlighted. Turn the large right knob to highlight the flight plan (FPL) field (Figure 4-6). Figure 4-6 Highlighted Flight Plan Field Turn the small right knob to display a window showing all waypoints in the active flight plan (Figure 4-7).
Page 66 SECTION 4 DIRECT-TO NAVIGATION Shortcuts Shortcuts are available when using the Direct-to Key, allowing the pilot to bypass the use of the small and large right knobs to enter the destination waypoint’ s identifier. A direct-to can be performed from any page displaying a single waypoint identifier (such as the WPT pages for airports and NAVAIDs).
Page 67 Selecting a Direct-to destination from the Map Page Direct-to destinations may also be selected from the Map Page. If no airport, NAVAID, or user waypoint exists at the desired location, a waypoint named ‘+MAP’ is automatically created at the location of the panning pointer.
Page 68 SECTION 4 DIRECT-TO NAVIGATION Specifying a Course to a Waypoint When performing a direct-to, the GNC 420 sets a direct great circle course to the selected destination. The course to the destination can also be manually defined using the ‘CRS’ course field on the Select Direct-to Waypoint Page. Manually defining the direct-to course: Press the Direct-to Key.
Page 69: Section 5: Flight Plans
SECTION 5: FLIGHT PLANS The GNC 420 lets the pilot create up to 20 different flight plans, with up to 31 waypoints in each flight plan. The Flight Plan Page Group consists of two pages (Active Flight Plan Page, Figure 5-1, and Flight Plan Catalog Page, Figure 5-2), accessed by pressing the FPL Key.
Page 70 SECTION 5 FLIGHT PLANS A blank Flight Plan Page appears for the first empty storage location (Figure 5-4). Use the small and large right knobs to enter the identifier of the departure waypoint and press the ENT Key. Figure 5-4 Flight Plan Page Repeat step 4 to enter the identifier for each additional flight plan waypoint.
Page 71 Deleting a waypoint from an existing flight plan: Press the FPL Key and turn the small right knob to display the Flight Plan Catalog Page. Press the small right knob to activate the cursor. Turn the large right knob to highlight the desired flight plan and press the ENT Key.
Page 72 SECTION 5 FLIGHT PLANS Activating Flight Plans Once a flight plan is defined through the Flight Plan Catalog Page (using the steps outlined previously in this section), it may be activated for navigation. Activating the flight plan places it into ‘flight plan 00’ and overwrites any previous information at that location.
Page 73 Copying Flight Plans To save a flight plan currently located in ‘flight plan 00’, be sure to copy it to an open catalog location (1-19) before the flight plan is cancelled, overwritten, or erased. Copying a flight plan to another flight plan catalog location: From the Active Flight Plan Page, press the MENU Key to display the Active Flight Plan...
Page 74 400/500-series Garmin unit. Some crossfill operations can be done automatically. If both units are set to ‘auto’, a change in the direct-to destination or active flight plan on one unit is seen on the other.
Page 75: Deleting All Flight Plans
The ‘Cross-side’ field allows the pilot to designate the sending and receiving units in a crossfill operation. Turn the large right knob to select the ‘Cross-side’ field, then turn the small right knob to select ‘To’ or ‘From’ (Figure 5-15). Press the ENT Key to confirm the selection.
Page 76: Active Flight Plan Page
SECTION 5 FLIGHT PLANS • ‘Sort List By Number?’/’Sort List by Comment?’ - Allows the pilot to sort numerically by the flight plan number or alphanumerically based upon the comment assigned to each flight plan. When one option is selected, the other option appears on the Flight Plan Catalog Page Menu.
Page 77 Activates/reactivates the flight plan and selects the highlighted leg as the ‘active leg’ (the leg Activate Leg which is currently used for navigation guidance). Allows the pilot to transfer the active flight plan between two 400/500-series Garmin units in Crossfill a dual unit installation. See Section 9.2, Flight Planning: Crossfill for additional information on this feature.
Page 78 SECTION 5 FLIGHT PLANS The data fields for DTK and DIS are user-selectable and may be changed to display cumulative distance (CUM) to each waypoint, estimated time of arrival (ETA), estimated time enroute (ETE), or enroute safe altitude (ESA). Changing a data field on the Active Flight Plan Page: With the Active Flight Plan Page displayed, press the MENU Key to display the Active Flight...
Page 79 Selecting an approach for a direct-to or flight plan destination airport: Choose the ‘Select Approach?’ option from the Active Flight Plan Page Menu (Figure 5-24) and press the ENT Key. Figure 5-24 Active Flight Plan Page Menu A window appears listing the available approaches (Figure 5-25) for the destination airport.
Page 80 SECTION 5 FLIGHT PLANS Selecting an arrival for a direct-to or flight plan destination airport: Select the ‘Select Arrival?’ option from the Active Flight Plan Page Menu (Figure 5-27) and press the ENT Key. Figure 5-27 Active Flight Plan Page Menu A window appears listing the available arrivals (Figure 5-28) for the destination airport.
Page 81 Removing an approach, arrival, or departure from the active flight plan: Select the ‘Remove Approach?’, ‘Remove Arrival?’ or ‘Remove Departure?’ option from the Active Flight Plan Page Menu (Figure 5-30) and press the ENT Key. Figure 5-30 Active Flight Plan Page Menu A confirmation window appears listing the procedure to be removed.
Page 82 SECTION 5 FLIGHT PLANS Shortcuts A number of shortcuts are available to save time when using the Active Flight Plan Page. These shortcuts speed the process of removing approaches, departures, and arrivals, and aid in selecting a specific flight plan leg for navigation guidance.
Page 83 The ‘Activate Leg?’ option is discussed previously in this section, which allows the pilot to specify which leg of the flight plan is used for navigation guidance. A shortcut also exists for this operation, using the Direct-to Key. Activating a specific leg of the active flight plan: Press the small right knob to activate the cursor and turn the large right knob to...
Page 84 SECTION 5 FLIGHT PLANS Blank Page 5-16 GNC 420(A) Pilot’s Guide and Reference 190-00140-20 Rev. K...
Page 85: Section 6: Procedures
SECTION 6: PROCEDURES 6.1 APPROACHES, DEPARTURES, AND ARRIVALS The GNC 420 allows the pilot to fly non-precision and precision approaches to airports with published instrument approach procedures. All available approaches are stored on the Jeppesen NavData Card, and are automatically updated when the new card is inserted into the GNC 420.
Page 86 GPS use. When selecting an approach, a ‘GPS’ designation to the right of the procedure name (Figure 6-4) indicates the procedure can be flown using the GPS receiver. Some procedures do not have this designation, meaning the GPS receiver may be used for supplemental navigation guidance only.
Page 87: Non-Precision Approach Operations
6.2 NON-PRECISION APPROACH OPERATIONS The GNC 420 provides non-precision approach guidance using its built-in GPS receiver. The GPS receiver can also be used as a supplemental aid for precision approaches, but external localizer and glideslope receivers must be used for primary approach course guidance.
Page 88 SECTION 6 PROCEDURES Select Destination ‘Select’ and ‘Load’ the approach ‘Activate’ the approach DO NOT USE FOR NAVIGATION Figure 6-8 Sample Approach Approach operations on the GNC 420 typically begin with the same basic steps (refer to Figure 6-8 for the following steps): Select the destination airport using the Direct- to Key, or as the last waypoint in the active...
Page 89 The steps required to set up and fly the approach are detailed below (refer to Figure 6-9 for the following steps): Prior to departing KFDK, the destination (KLYH) is selected using the Direct-to Key or by creating a flight plan terminating at Lynchburg Regional.
Page 90 SECTION 6 PROCEDURES Flying the Procedure Turn      DO NOT USE FOR NAVIGATION Figure 6-13 Sample Approach with Procedure Turn Refer to Figure 6-13 for the following steps: Within 30 nm of the destination airport, the GNC 420 switches from ‘enroute’...
Page 91 Figure 6-16 Waypoint Alert Fly the outbound course. Approximately one minute after passing the FAF (LYH), the alert message ‘START PROC TRN’ appears in the lower right corner of the screen. Initiate the procedure turn at any time after receiving this alert message. DO NOT USE FOR NAVIGATION ...
Page 92 SECTION 6 PROCEDURES 11) After crossing the FAF, the destination sequences to the MAP (‘RW03’, the runway threshold, see Figure 6-19). Fly toward the MAP. Figure 6-19 Sequence to MAP NOTe: When viewing the Map Page, note that the final course segment is displayed in magenta (the active leg of the flight plan always appears in magenta) and a dashed line extends the course beyond the MaP.
Page 93 The OBS Key is used to initiate the missed approach, as follows (refer to Figure 6-21 for the following steps): Press the OBS Key. The missed approach holding point (MAHP; in this case ‘SWARM’ intersection) is automatically offered as the destination waypoint (Figure 6-22).
Page 94 SECTION 6 PROCEDURES Flying an Approach with a Hold Starting where the previous example left off, assume weather conditions resulted in a missed approach at Lynchburg Regional. The pilot has decided to divert to Farmville Regional (KFVX) instead (refer to Figure 6-25 for the following steps).
Page 95 Figure 6-29 Active Flight Plan Page  Figure 6-30 Terminal Mode Refer to Figure 6-30 for the following steps. As in the last example, within 30 nm of the airport, the GNC 420 switches from enroute to terminal mode, and the CDI scale transitions from 5.0 to 1.0 nm, full scale deflection.
Page 96 SECTION 6 PROCEDURES NOTe: if the pilot needs to lose extra altitude or speed by going around the holding pattern again, press the OBS Key to manually suspend waypoint sequencing before crossing the holding waypoint the second time. if this waypoint has already been passed, re-activate the holding pattern using the steps described in Section 5.2.
Page 97 13) When approaching the FAF, a waypoint alert (‘NEXT DTK 209°’) appears in the lower right corner (Figure 6-35). Make any course adjustments necessary for the final course segment (FAF to MAP). Figure 6-35 Final Approach 14) After crossing the FAF, the destination sequences to the MAP (‘RW21’, the runway threshold).
Page 98 SECTION 6 PROCEDURES Flying a DME Arc Approach The GPS overlay for a DME arc approach uses additional Jeppesen-provided waypoints to define the arc. These waypoints are indicated by ‘D’ as the first letter in the waypoint name. This is followed by three numbers which indicate the radial the waypoint lies on.
Page 99 Figure 6-40 Approach Window DO NOT USE FOR NAVIGATION      Billard Muni (Topeka, KS) VOR or GPS Rwy 22 Figure 6-41 Terminal Mode Refer to Figure 6-41 for the following steps. Within 30 nm of KTOP, the GNC 420 switches from enroute mode to terminal mode and the CDI scale transitions from 5.0 to 1.0 nm, full scale deflection.
Page 100 SECTION 6 PROCEDURES The next point in the approach is an intermediate fix, labeled ‘D025G’. When approaching this intermediate fix, a waypoint alert (‘NEXT DTK 205°’) appears in the lower right corner of the screen (Figure 6-44). As the distance to this fix approaches zero, the alert is replaced by a turn advisory (‘TURN TO 205°’).
Page 101 10) After crossing the FAF, the destination sequences to the MAP (‘RW22’, the runway threshold). With the needle centered, fly toward the MAP, observing the altitude minimums dictated by the approach plate. When viewing the Map Page, note that the final course segment is displayed in magenta (the active leg of the flight plan always appears in magenta) and a dashed line extends the course...
Page 102 SECTION 6 PROCEDURES Selecting ‘VECTORS’ from the Transitions Window: Select Billard Municipal (KTOP) as the destination, using the Direct-to Key, or as the last waypoint in a flight plan. Press the PROC Key and select the ‘VOR 22’ approach using the steps outlined in Section 6.1.
Page 103 DO NOT USE FOR NAVIGATION     Figure 6-52 Terminal Mode In this example, we’ll assume ATC vectors result in a rectangular course to intercept final, as follows (refer to Figure 6-52 for the following steps): Within 30 nm of KTOP, the GNC 420 switches from enroute mode to terminal mode and the CDI scale transitions from 5.0 to 1.0 nm, full scale deflection.
Page 104 SECTION 6 PROCEDURES      DO NOT USE FOR NAVIGATION Figure 6-56 Approach Mode Refer to Figure 6-56 for the following steps. At 2.0 nm from the FAF (TOP VOR), the GNC 420 switches from terminal mode to approach mode (Figure 6-57).
Page 105 Course From Fix Flight Plan Legs Certain approach, departure, and arrival procedures in the Jeppesen database contain course from fix flight plan legs. The GNC 420 is able to load these legs into the flight plan along with the rest of the procedure data, and provide navigation along these legs.
Page 106 SECTION 6 PROCEDURES Figure 6-62 Default NAV Page Figure 6-63 Map Page At 13.0 nm from the FAF, a waypoint alert (‘NEXT DTK 265°’) appears in the lower right corner of the screen. Turn to intercept the final approach course and watch for the CDI needle to begin to center.
Page 107 Course from fix to altitude legs show the specific target altitude on the Active Flight Plan Page (Figure 6-64) and the Default NAV Page (Figure 6-65). The missed approach sequence for the Palmdale VOR/DME RWY 25 approach includes a course from fix to altitude leg. Figure 6-64 Active Flight Plan Page Figure 6-65 Default NAV Page 190-00140-20 Rev.
Page 108 SECTION 6 PROCEDURES Fly the outbound course. The Map Page depicts the flight path extending indefinitely from PMD VOR (Figure 6-67). The distance (DIS) on the Default NAV Page, the Map Page, and the Active Flight Plan Page increases, indicating the distance back to PMD VOR.
Page 109 Course from fix to manual sequence legs appear on the Active Flight Plan Page and the Map Page with ‘man seq’ in place of a waypoint identifier. An example of this type of course leg appears in the COASTAL ONE DEPARTURE from Westfield, Massachusetts (Barnes Municipal).
Page 110: Points To Remember For All Approaches
SECTION 6 PROCEDURES Fly the outbound course. Once cleared to sequence to the next leg, press the OBS Key. Confirm that ‘SUSP’ no longer appears directly above the OBS Key. An alert (‘NEXT DTK 186°’) appears in the lower right corner of the screen (Figure 6-72) to provide guidance to the next waypoint (HFD VOR).
Page 111: Section 7: Wpt Pages
SECTION 7: WPT PAGES 7.1 WPT PAGE GROUP Section 2 introduced the GNC 420’ s main page groups (Table 7-1)—NAV, WPT, AUX, NRST—and described each page in the NAV group. This second page group (WPT) provides information for the thousands of airports, VORs, NDBs, intersections, runways, frequencies, and procedures stored on the Jeppesen NavData Card.
Page 112 SECTION 7 WPT PAGES Entering a waypoint identifier: Select the desired WPT page and press the small right knob to activate the cursor. Turn the small right knob to select the first character of the waypoint’s identifier. Turn the large right knob to select the next character field.
Page 113 Duplicate Waypoints Once the identifier, facility name, or location is entered, all six airport pages display information for the selected airport. When entering an identifier, facility name, or location, the GNC 420’ s Spell’N’Find feature scrolls through the database, displaying those waypoints matching the characters that have been entered to that point.
Page 114: Airport Location Page
SECTION 7 WPT PAGES 7.2 AIRPORT LOCATION PAGE The Airport Location Page (Figure 7-8) displays the latitude, longitude, and elevation of the selected airport. The Airport Location Page also displays facility name and location, as well as fuel availability, available approaches, radar coverage, and airspace type.
Page 115: Airport Runway Page
7.3 AIRPORT RUNWAy PAGE The Airport Runway Page (Figure 7-9) displays runway designations, length, surface type, and lighting for the selected airport. A map image of the runway layout and surrounding area is also displayed on the Airport Runway Page. The map image range appears in the lower left corner and is adjustable using the RNG Key.
Page 116: Airport Frequency Page
SECTION 7 WPT PAGES Adjusting the range of the map image: Press the down arrow of the RNG Key to display a smaller map area. Press the up arrow of the RNG Key to display a larger map area. The following descriptions and abbreviations are used on the Airport Runway Page: •...
Page 117 Turn the large right knob to scroll through the list, placing the cursor on the desired frequency (Figure 7-13). If there are more frequencies in the list than can be displayed on the screen, a scroll bar (Figure 7-12) along the right-hand side of the screen indicates the cursor’s position within the list.
Page 118: Airport Approach Page
SECTION 7 WPT PAGES The following descriptions and abbreviations are used on the Airport Frequency Page: • Type - Usage type: Public, Heliport, Military, or Private • Frequency - Communication frequencies which may include restrictions: Approach Arrival Class C Terminal Communication frequencies without restrictions: ATIS ASOS...
Page 119 GPS use. When selecting an approach, a ‘GPS’ designation to the right of the procedure name indicates the procedure can be flown using the GPS receiver. Some procedures do not have this designation, meaning the GPS receiver may be used for supplemental navigation guidance only.
Page 120 SECTION 7 WPT PAGES Airport Approach Page Options The available options for the Airport Approach Page, can be displayed (Figure 7-21) by pressing the MENU Key: ‘Load into Active FPL?’ - Allows the pilot to load the selected approach into the active flight plan without activating it.
Page 121: Airport Arrival Page
7.6 AIRPORT ARRIVAL PAGE The Airport Arrival Page (Figure 7-22) shows the available Airport Standard Terminal Arrival (STAR) procedures for the selected airport. Where multiple transitions or runways are associated with the arrival procedure, that information may also be displayed. A map image provides a layout diagram for each arrival, transition, and runway.
Page 122 SECTION 7 WPT PAGES Turn the small right knob to display a window of available runways (Figure 7-25). Continue turning the small right knob to select the desired runway. ‘ALL’ may appear in the runway field, indicating the arrival procedure applies to all runways.
Page 123: Airport Departure Page
7.7 AIRPORT DEPARTURE PAGE The Airport Departure Page (Figure 7-27) shows the available Airport Standard Instrument Departure (SID) procedures for the selected airport. Where multiple runways or transitions are associated with the departure procedure, that information may also be displayed. A map image provides a layout diagram for each departure, runway, and transition.
Page 124: Intersection Page
SECTION 7 WPT PAGES Airport Departure Page Options The following option is available for the Airport Departure Page, by pressing the MENU Key: Load into Active FPL? allows the pilot to load the selected departure into the active flight plan. This is identical to loading a departure procedure from the Procedures Page, as described in Section 6.1.
Page 125: Ndb Page
7.9 NDB PAGE The NDB Page displays the facility name, city, region/country, latitude, and longitude for the selected NDB (Figure 7-32). The NDB Page also displays the frequency and a weather broadcast indication (if applicable). As mentioned in Section 7.1, NDBs may be selected by identifier, facility name, or location (city).
Page 126: User Waypoint Page
SECTION 7 WPT PAGES 7.11 USER WAyPOINT PAGE In addition to the airport, VOR, NDB, and intersection information contained in the Jeppesen NavData Card, the GNC 420 allows the pilot to store up to 1,000 user- defined waypoints. The User Waypoint Page (Figure 7-34) displays the waypoint name (up to five characters long), identifier, radial from two reference waypoints, and distance from one reference waypoint, along with the user...
Page 127 Turn the large right knob to highlight the position field at the bottom of the page. Use the small and large right knobs to enter the position coordinates for the new waypoint (Figure 7-37). Figure 7-37 Present Position Field Selected Press the ENT Key to accept the selected position.
Page 128 SECTION 7 WPT PAGES Turn the large right knob to highlight ‘Create?’ (Figure 7-39) and press the ENT Key. Figure 7-39 ‘Create?’ Highlighted Press the small right knob to remove the flashing cursor. Creating Reference Waypoints The GNC 420 allows the pilot to create a new user waypoint at a defined radial and distance from the present position.
Page 129 Press the ENT Key to capture the position and display the User Waypoint Page (Figure 7-41). Figure 7-41 User Waypoint Page A four-digit name is automatically assigned to the waypoint. To change this name, turn the large right knob to highlight the name field, then use the small and large right knobs to select a new name.
Page 130 SECTION 7 WPT PAGES Modifying a user waypoint by changing reference waypoint information: With the User Waypoint Page displayed, press the small right knob to activate the cursor. Use the small and large right knobs to enter the name of the desired waypoint and press the ENT Key.
Page 131 User Waypoint Page Options The following User Waypoint Page options are available by pressing the MENU Key: ‘View User Waypoint List?’ displays a list of all user waypoints currently stored in memory. Viewing a list of all user waypoints: From the User Waypoint Page, press the MENU Key to display the User Waypoint Page Menu.
Page 132 SECTION 7 WPT PAGES User Waypoint List The User Waypoint List (Figure 7-49) allows the pilot to review, modify, rename, or delete a selected user waypoint, or to delete all user waypoints currently stored in memory. The top of the page shows the number of waypoints used and available memory.
Page 133 Deleting a user waypoint from the User Waypoint List: Select the User Waypoint List, as described in this section. Turn the large right knob to highlight the desired user waypoint. Press the CLR Key to display a ‘delete waypoint’ confirmation window (Figure 7-52). Figure 7-52 Delete Waypoint Window With ‘Yes?’...
Page 134 SECTION 7 WPT PAGES Blank Page 7-24 GNC 420(A) Pilot’s Guide and Reference 190-00140-20 Rev. K...
Page 135: Section 8: Nrst Pages
SECTION 8: NRST PAGES 8.1 NRST PAGE GROUP Section 3.1 introduced the GNC 420’ s main page groups (Table 8-1)—NAV, WPT, AUX, NRST—and described each page in the NAV group. This fourth page group (NRST) provides detailed information for the nine nearest airports, VORs, NDBs, intersections, and user waypoints within 200 nm of the current position.
Page 136 SECTION 8 NRST PAGES Not all nine nearest airports, VORs, NDBs, intersections, or user waypoints can be displayed on the corresponding NRST page at one time. The Nearest Airport Page displays detailed information for three nearest airports, with a scroll bar along the right-hand side of the page indicating which part of the list is currently being viewed.
Page 137 Navigating to a Nearby Waypoint The NRST pages can be used in conjunction with the GNC 420’ s direct-to function to quickly set a course to a nearby facility, and can provide navigation to the nearest airport in case of an in-flight emergency. Selecting a nearby airport, VOR, NDB, intersection, or user waypoint as a direct- to destination:...
Page 138: Nearest Airport Page
SECTION 8 NRST PAGES 8.2 NEAREST AIRPORT PAGE The Nearest Airport Page displays the identifier, symbol, bearing, and distance to the nine nearest airports (within 200 nm of the present position). For each airport listed, the Nearest Airport Page also indicates the best available approach, common traffic advisory frequency (CTAF), and the length of the longest runway (Figure 8-8).
Page 139 Press the COM Flip-flop Key to activate the selected frequency (Figure 8-11). Figure 8-11 Frequency Moved to Active Field Press the small right knob to remove the flashing cursor. Additional communication frequencies, runway information, and more is available from the Nearest Airport Page by highlighting the identifier of the desired airport and pressing the ENT Key.
Page 140: Nearest Intersection Page
SECTION 8 NRST PAGES 8.3 NEAREST INTERSECTION PAGE The Nearest Intersection Page (Figure 8-15) displays the identifier, symbol, bearing, and distance to the nine nearest intersections (within 200 nm of the present position). To view additional information for a nearby intersection, start from the Nearest Intersection Page and follow the preceding steps 2 through 4.
Page 141: Nearest Vor Page
8.5 NEAREST VOR PAGE The Nearest VOR Page (Figure 8-17) displays the identifier, symbol, bearing, and distance to the nine nearest VORs (within 200 nm of the present position). For each VOR listed, the nearest VOR Page also indicates the frequency of the nearby VOR for reference in tuning a VOR receiver.
Page 142: Nearest Center (Artcc) Page
SECTION 8 NRST PAGES 8.7 NEAREST CENTER (ARTCC) PAGE The Nearest Center Page (Figure 8-20) displays the facility name, bearing to, and distance to the five nearest ARTCC points of communication (within 200 nm of the present position). For each ARTCC listed, the Nearest Center Page also indicates one or more frequencies and may be used to quickly tune the COM transceiver to the center’...
Page 143: Nearest Flight Service Station (Fss) Page
8.8 NEAREST FLIGHT SERVICE STATION (FSS) PAGE The Nearest Flight Service Station Page (Figure 8-23) displays the facility name, bearing to, and distance to the five nearest FSS points of communication (within 200 nm of the present position). For each FSS listed, the Near- est Flight Service Station Page also indicates one or more frequencies and may be used to quickly tune the COM transceiver to the FSS’...
Page 144: Nearest Airspace Page
SECTION 8 NRST PAGES Press the ENT Key to place the selected frequency in the standby field of the COM (Figure 8-26). Figure 8-26 Frequency Moved to Standby Field Press the COM Flip-flop Key to activate the selected frequency. Press the small right knob to remove the flashing cursor.
Page 145 • If the aircraft has entered an airspace, the message ‘Inside Airspace’ appears (Figure 8-28). The Nearest Airspace Page shows ‘Inside of airspace’. Figure 8-28 Airspace Messages Note that the airspace alerts are based on three- dimensional data (latitude, longitude, and altitude) to avoid nuisance alerts.
Page 146 SECTION 8 NRST PAGES Turn the large right knob to scroll through the list, highlighting the desired airspace (Figure 8-31). Figure 8-31 Airspace Highlighted Press the ENT Key to display the Airspace Page for the selected nearby airspace (Figure 8-32). Airspace Name Status and Floor/Ceiling...
Page 147 To return to the Airspace Page, turn the large right knob to highlight ‘Done?’ and press the ENT Key (or press the CLR Key). To return to the Nearest Airspace Page, turn the large right knob to highlight ‘Done?’ and press the ENT Key (or press the CLR Key).
Page 148 SECTION 8 NRST PAGES Blank Page 8-14 GNC 420(A) Pilot’s Guide and Reference 190-00140-20 Rev. K...
Page 149: Section 9: Aux Pages
SECTION 9: AUX PAGES 9.1 AUX PAGE GROUP Section 3.1 introduced the GNC 420’ s main page groups (Table 9-1)—NAV, WPT, AUX, NRST—and described each page in the NAV group. The third page group (AUX) allows the pilot to change unit settings. The AUX pages (Figure 9-1) also provide trip planning, fuel planning, density altitude, true airspeed, and winds aloft calculations.
Page 150: Flight Planning Page
SECTION 9 AUX PAGES 9.2 FLIGHT PLANNING PAGE The Flight Planning Page (Figure 9-4) provides access (via ‘menu options’) to E6B functions for fuel planning, trip planning, density altitude/true airspeed/winds aloft calculations, and a ‘Crossfill’ function to transfer flight plans/user waypoints to a second GNC 420. When a menu option is selected, the corresponding page appears providing additional information and features.
Page 151 • Crossfill - Allows the pilot to transfer the active flight plan, any stored flight plan, a user waypoint, or all user waypoints between two 400/500-series Garmin units in a dual-unit installation. See Section 5.1, Flight Plan Catalog Options and information following in this section for details.
Page 152 SECTION 9 AUX PAGES Flight Planning Page: Fuel Planning Performing fuel planning operations: Select ‘Fuel Planning’ from the Flight Planning Page, using the steps described in Section 9.2. The current fuel planning ‘mode’ is displayed at the top of the page (Figure 9-7): ‘POINT TO POINT’...
Page 153 If the fuel management system does not enter the data automatically, turn the large right knob to highlight the fuel on board (FOB) field (Figure 9-11). Figure 9-11 FOB Highlighted Use the small and large right knobs to enter the amount of fuel on board. Press the ENT Key when finished.
Page 154 SECTION 9 AUX PAGES Fuel planning figures can be entered and displayed based upon one of three possible configurations: • No fuel sensors connected - In this instance fuel flow is manually entered and is used to calculate fuel on board. When fuel flow or fuel on board is manually entered, the figures are retained the next time the page is displayed (with fuel on board continuously recalculated).
Page 155 Turn the large right knob to highlight the departure time (DEP TIME) field. Use the small and large right knobs to enter the departure time. Press the ENT Key when finished. Departure time may be entered in local or UTC time, depending upon unit settings, see Section 9.4, Setup 1 Page: Date/Time.
Page 156 SECTION 9 AUX PAGES The flashing cursor moves to the barometric pressure (BARO) field. Use the small and large right knobs to enter the barometric pressure (altimeter setting). Press the ENT Key when finished. The flashing cursor moves to the total air temperature (TAT) field.
Page 157 Turn the small right knob to select ‘Auto’ or ‘Manual’ (Figure 9-23). ‘Auto’ automatically transfers any selection of (or any change to) a direct-to destination or active flight plan to a second 400/500-series Garmin unit. 190-00140-20 Rev. K Figure 9-23 Crossfill Method Window NOTe: Crossfill requires both 400/500-series units to have the same Jeppesen NavData database cycle number.
Page 158 SECTION 9 AUX PAGES • Active Flight Plan - Transfer the active flight plan to/from a second 400/500-series Garmin unit in a dual unit installation. This option is the default when selecting ‘Crossfill’ from the Active Flight Plan Page. • Flight Plan - Transfer any stored flight plan to/from a second 400/500-series unit, by selecting the flight plan by number.
Page 159 The flashing cursor moves to the type field under the new message (Figure 9-27). Turn the small right knob to display a window of available options (Figure 9-28): Event, One Time, Periodic. Press the ENT Key to select. Figure 9-27 Type Field Highlighted Figure 9-28 Type Window The flashing cursor moves to the time/date field.
Page 160: Utility Page
SECTION 9 AUX PAGES 9.3 UTILITy PAGE The Utility Page (Figure 9-29) provides access (via menu options) to checklists, a count down/up timer, trip timers, trip statistics, RAIM (Receiver Autonomous Integrity Monitoring) prediction, sunrise/sunset time calculations, software versions, database versions, and terrain database version information.
Page 161 An ‘INTEG’ annunciation at the bottom left corner of the screen (Figure 9-32) indicates that satellite coverage is insufficient to pass built-in RAIM tests. When this occurs, the GPS receiver continues to provide navigation information, but should not be used for primary navigation guidance. Use an alternate navigation source.
Page 162 SECTION 9 AUX PAGES Utility Page: Checklists Creating a checklist: Select ‘Checklist’ from the Utility Page (Figure 9-33), using the steps described at the beginning of this section (9.3). Press the ENT Key to display a list of checklists. Figure 9-33 Checklists Highlighted Press the MENU Key to display an options menu.
Page 163 Inserting a checklist step into an existing checklist: With the Checklists Page displayed, turn the large right knob to select the desired checklist and press the ENT Key. Turn the large right knob to highlight the existing checklist entry which immediately follows the new checklist step.
Page 164 SECTION 9 AUX PAGES For a count down timer, turn the large right knob to highlight the time field. Use the small and large right knobs to enter the count down time—in hours, minutes, and seconds. Press the ENT Key when finished. To stop the generic timer, turn the large right knob to highlight ‘Stop?’...
Page 165 Utility Page: Trip Statistics Resetting trip statistics readouts: Select ‘Trip Statistics’ from the Utility Page (Figure 9-40), using the steps described at the beginning of this section. Figure 9-40 Trip Statistics Highlighted Press the MENU Key to display the Trip Statistics Page Menu with several reset options (Figure 9-41): •...
Page 166 SECTION 9 AUX PAGES The flashing cursor moves to the arrival date field. Use the small and large right knobs to enter the date for which the pilot wants to determine RAIM availability. Press the ENT Key when finished. The flashing cursor moves to the arrival time field.
Page 167 Press the ENT Key to calculate sunrise and sunset times for the selected location and date (Figure 9-47). Figure 9-47 Sunrise/Sunset Page Utility Page: Software Versions The Software Versions Page (Figure 9-48) displays software version information for each of the various subsystems contained within the GNC 420.
Page 168: Setup 1 Page
SECTION 9 AUX PAGES 9.4 SETUP 1 PAGE The Setup 1 Page provides access (via menu options) to airspace alarms, CDI scale adjustment, an arrival alarm, units of measure settings, position formats, map datums, and settings for local or UTC time display. When a menu option is selected, the corresponding page appears providing access to the various unit settings.
Page 169 True, Auto, or User-defined. If ‘Auto’ is selected, all track, course and heading information is corrected to the magnetic variation computed by the GPS receiver. The ‘True’ setting references all information to true north, and the ‘User’ setting corrects information to an user-entered value.
Page 170 SECTION 9 AUX PAGES • ‘Position/Map Datum’ - Configures position readout information to the desired position format. The map datum used in the GNC 420 is WGS 84. Note that using a map datum that does not match the charts can result in significant differences in position information.
Page 171 To change the altitude buffer, turn the large right knob to highlight the ‘Altitude Buffers’ field (Figure 9-57). Use the small and large right knobs to enter the desired buffer distance. Press the ENT Key when finished. Figure 9-57 Buffer Distance Field Selected NOTe: When an approach has been loaded into the active flight plan, airspace alert messages are disabled within 30nm of the destination...
Page 172 SECTION 9 AUX PAGES Setting the arrival alarm and alarm distance: Select ‘CDI/Alarms’ from the Setup 1 Page, using the steps described at the beginning of this section. Turn the large right knob to highlight the ‘On’/’Off’ field (directly below ‘Arrival Alarm’). Turn the small right knob to select ‘On’...
Page 173 Changing the units of measure: Select ‘Units/Mag Var’ from the Setup 1 Page, using the steps described at the beginning of this section. Turn the large right knob to highlight the desired units of measure category (Figure 9-63). Figure 9-63 Units Mag/Var Page The following categories, and corresponding units of measure, are available: •...
Page 174 SECTION 9 AUX PAGES Displaying the map datum: Select ‘Position Format/Map Datum’ from the Setup 1 Page, using the steps described at the beginning of this section. The WGS 84 map datum is displayed, this field cannot be changed. Figure 9-66 Map Datum Field Highlighted Setup 1 Page: Date/Time Displaying local time or UTC: Select ‘Date/Time’...
Page 175: Setup 2 Page
Restoring Factory Settings When making changes to any Setup 1 Page option, a ‘Restore Defaults?’ menu selection allows the pilot to restore the original factory settings (for the selected option only). For example, with the Airspace Alarms Page displayed, the ‘Restore Defaults?’ option restores all Airspace Alarms Page settings to the original factory values.
Page 176 SECTION 9 AUX PAGES Turn the large right knob to select the desired menu option (Figure 9-71), and press the ENT Key (Figure 9-72). Figure 9-71 Nearest Airport Criteria Highlighted Figure 9-72 Nearest Airport Criteria Page The following menu options are available: •...
Page 177 Setup 2 Page: Display Changing the backlighting intensity: Select ‘Display’ from the Setup 2 Page (Figure 9-73), using the steps described at the beginning of this section (9.5). Figure 9-73 Display Highlighted The flashing cursor highlights the backlight mode field. Turn the small right knob to select the desired mode: Auto or Manual (Figure 9-74).
Page 178 SECTION 9 AUX PAGES Setup 2 Page: Nearest Airport Criteria Setting the minimum runway length and runway surface: Select ‘Nearest Airport Criteria’ from the Setup 2 Page, using the steps described at the beginning of this section. The flashing cursor highlights the runway surface field (Figure 9-76).
Page 179 Setup 2 Page: Data Field Configuration Configuring the Data Fields: Select ‘Data Field Configuration’ from the Setup 2 Page, using the steps described at the beginning of this section. The flashing cursor highlights the data field (Figure 9-79). Figure 9-79 Upper Data Field Highlighted Turn the small right knob to select the desired data type (Figure 9-80).
Page 180 SECTION 9 AUX PAGES Turn the small right knob to select an option from the Auxiliary Configuration Window (Figure 9-82). Figure 9-82 AUX CONFIG Window Selecting ‘Config Fields’ configures the data field to display user selectable data information. Selecting ‘Traffic’ configures the data field to display thumbnail traffic information (Figure 9-83).
Page 181: Section 10: Terrain
TERRAIN uses terrain and obstacle information supplied by government sources. The data undergoes verification by Garmin to confirm accuracy of the content, per TSO-C151b. However, the displayed information should never be understood as being all-inclusive. GNC 420(A) Pilot’s Guide and Reference...
Page 182 SECTION 10 TERRAIN TERRAIN Alerting TERRAIN uses information provided from the GPS receiver to provide a horizontal position and altitude. GPS altitude is derived from satellite measurements. GPS altitude is converted to a mean sea level (MSL)-based altitude (GPS-MSL altitude) and is used to determine TERRAIN alerts.
Page 183: Terrain Page
10.2 TERRAIN PAGE See Section 3.5 for a complete description of the TERRAIN Page and its operation. TERRAIN Symbols The symbols and colors in Figure 10-1 and Table 10-1 are used to represent obstacles and potential impact points on the TERRAIN Page. TERRAIN uses yellow (caution) and red (warning) to depict terrain information relative to aircraft altitude.
Page 184: Terrain Alerts
SECTION 10 TERRAIN 10.3 TERRAIN ALERTS TERRAIN Alerts are issued when flight conditions meet parameters that are set within TERRAIN software algorithms. TERRAIN alerts typically employ either an ADVISORY or a CAUTION alert severity level, or both. When an alert is issued, visual annunciations are displayed.
Page 185 Table 10-2 shows the possible TERRAIN alert types with corresponding annunciations. Alert Type TERRAIN Failure TERRAIN Inhibited TERRAIN Not Available Required Terrain Clearance (RTC) Advisory Required Terrain Clearance (RTC) Caution Imminent Terrain Impact (ITI) Advisory Imminent Terrain Impact (ITI) Caution Required Obstacle Clearance (ROC) Advisory Required Obstacle Clearance (ROC) Caution Imminent Obstacle Impact (IOI) Advisory...
Page 186 SECTION 10 TERRAIN Table 10-3 shows system status annunciations that may also be issued: Alert Type TERRAIN System Test Fail TERRAIN Alerting is disabled No GPS position or excessively degraded GPS signal System Test in progress System Test pass Forward Looking Terrain Avoidance The Forward Looking Terrain Avoidance (FLTA) alert is used by TERRAIN and is composed of: •...
Page 187 Premature Descent Alerting A Premature Descent Alert (PDA) is issued when the system detects that the aircraft is significantly below the normal approach path to a runway (Figure 10-5). PDA alerting begins when the aircraft is within 15 nm of the destination airport. PDA alerting ends when the aircraft is either: •...
Page 188 SECTION 10 TERRAIN TERRAIN NOT AVAILABLE ALERT TERRAIN requires a 3-D GPS navigation solution along with specific vertical accuracy minimums. Should the navigation solution become degraded or if the aircraft is out of the database coverage area, the annunciation ‘TER N/A’ is generated in the annunciation window and ‘TERRAIN NOT AVAILABLE’...
Page 189: Database Information For Terrain
General Database Information Garmin TERRAIN uses terrain and obstacle information supplied by government sources. The data undergoes verification by Garmin to confirm accuracy of the content, per TSO-C151b. However, the displayed information should never be understood as being all- inclusive. Pilots must familiarize themselves with the appropriate sectional charts for safe flight.
Page 190 (compare database cycle numbers to determine if a newer version is available). Updated terrain data cards may be obtained by calling Garmin at one of the numbers listed in the front of this document. Updating terrain/obstacle databases: Acquire a new terrain data card from Garmin.
Page 191: Section 11: Additional Features
TIS Traffic display is available to aircraft equipped with a Mode S Data Link, such as the Garmin GTX 330 Transponder. TIS traffic information from a GTX 330 Transponder can then be displayed on a GNC 420 unit.
Page 192 11-2 TIS Limitations NOTe: This section on TiS Limitations is not comprehensive. Garmin recommends the user review the TiS Limitations section of the 3,500 ft aeronautical information Manual, Section 1-3-5.
Page 193 comes between the transponder antenna (usually located on the underside of the aircraft) and the ground-based radar antenna, the signal may be temporarily interrupted. Other limitations and anomalies associated with TIS are described in the AIM, Section 1-3-5. TiS is unavailable at low altitudes in many areas of the U.S., particularly in mountainous regions.
Page 194 SECTION 11 ADDITIONAL FEATURES TIS Audio Alerting The TIS audio alert is generated when the number of Traffic Advisories (TA) on the GNC 420 display increases from one scan to the next. For example, when the first TA appears on the TIS display, the user is alerted audibly. As long as a single aircraft remains on the TIS display, no further audio alert is generated.
Page 195 Altitude Deviation Traffic Type Figure 11-4 Traffic Symbol Components Traffic Type Description Traffic This symbol (solid yellow circle) is generated Advisory (TA) when an intruder aircraft approaches on a course that projects to intercept (defined by a 0.5 nm horizontal radius and a relative altitude of ±...
Page 196 SECTION 11 ADDITIONAL FEATURES • DATA FAIL - ‘DATA FAIL’ is displayed when data is being received from GTX 330 (Figure 11-7), but there was a failure detected in the data stream. The pilot should see the installer for corrective action.
Page 197 Figure 11-11 Traffic Removed Banner • UNAVAIL - When a 60 second period elapses with no data, TIS is considered to be unavailable. This state is indicated by the text ‘UNAVAIL’ (Figure 11-12). The pilot should be aware that ‘UNAVAIL’ could indicate a TIS coverage limitation due to a line-of-sight situation, a low altitude condition, or a result of flying directly over the radar site...
Page 198 SECTION 11 ADDITIONAL FEATURES Traffic Page Display Range Various display ranges can be selected for optimal display of TIS traffic information. Changing the display range on the Traffic Page: Press the RNG Key to zoom through the range selections which are: 12/6 nm, 6/2 nm, and 2 nm.
Page 199 Thumbnail Traffic on Map Page The Map Page can display traffic in a thumbnail format in any of the top three data fields on the right-hand side of the Map Page. Displaying Thumbnail Traffic on the Map Page: Turn the small right knob to select the Map Page.
Page 200 SECTION 11 ADDITIONAL FEATURES Power-Up Test The TIS interface performs an automatic test during power-up. • If the system passes the power-up test, the Standby Screen appears on the Traffic Page. • If the system passes the power-up test and the aircraft is airborne (as determined by system configuration at the time of installation, see the installer for detailed criteria information), traffic is...
Page 201: Gts 8Xx Traffic Systems
11.2 GTS 8XX TRAFFIC SySTEMS Introduction All information in this section pertains to the display and control of the Garmin GNC 420/GTS 8XX interface, refer to the 400/500 Series Display Interfaces Pilot’ s Guide Addendum (190-00140-10) when interfacing with non-Garmin products...
Page 202 SECTION 11 ADDITIONAL FEATURES Pilots should be aware of TAS/TCAS system limitations. If an intruder transponder does not respond to interrogations due to antenna shading or marginal transponder performance, it will not be displayed, or display may be intermittent. Pilots should remain vigilant for traffic at all times when using TAS/TCAS systems for non-transponder equipped airplanes or unresponsive airplanes.
Page 203 Aural Alerts A TA consists of a displayed traffic symbol (solid yellow circle) and an aural alert. The aural alert announces “traffic”, followed by the intruder aircraft’ s position, altitude relative to own aircraft (“high”, “low”, or “same altitude”), and distance from own aircraft; e.g. “traffic, 12 o’clock, high, 3 miles”.
Page 204 SECTION 11 ADDITIONAL FEATURES Switching Between Standby and Operating Modes The unit must be in operating mode for traffic to be displayed. The ability to switch out of standby into operating mode on the ground is especially useful for scanning the airspace around the airport before takeoff.
Page 205 Altitude Display Mode The GTS 8XX has four altitude display modes (Figure 11-24); Normal (±2,700 ft), Above (-2,700 ft to +9,000 ft), Below (-9,000 ft to +2,700 ft), and Unrestricted (±9,900 ft). The GTS 8XX continues to display up to 30 intruder aircraft within its maximum surveillance range, regardless of the altitude display mode selected.
Page 206 SECTION 11 ADDITIONAL FEATURES Traffic Warning Window When the unit is not on the traffic page and the GTS issues a Traffic Advisory, the Traffic Warning Window (Figure 11-26) is displayed, which shows a small thumbnail map. When the Traffic Warning Window is displayed, press the ENT Key to display the Traffic Page, or press the CLR Key to return to the previous page.
Page 207 10) Return to the Map Page by pressing the CLR Key. Thumbnail Traffic on Map Page Traffic in a thumbnail format can be displayed in any of the three data fields on the right side of the Map Page (Figure 11-29). Displaying Thumbnail Traffic on the Map Page Turn the small right knob to select the Map...
Page 208: Weather Data Link Interface
ADDITIONAL FEATURES 11.3 WEATHER DATA LINK INTERFACE This section is written for: • Garmin GNC 420 Main System Software Version 5.01 and later • GDL 49 Main Software Version 2.03 and later • GDL 69/69A Main Software Version 2.14 and later...
Page 209 Weather Products The following weather products are available for display on the GNC 420 unit via the Weather Data Link interface: • NEXRAD Data • Graphical METAR Data • Text-based METAR Data • Graphical Temperature/Dewpoint Data • Graphical Wind Data NEXRAD Description WSR-88D weather surveillance radar or NEXRAD (NEXt generation RADar) is a Doppler radar system that...
Page 210: Nexrad Intensity
SECTION 11 ADDITIONAL FEATURES NEXRAD Intensity Colors are used to identify the different NEXRAD echo intensities (reflectivity) measured in dBZ (decibels of Z). Reflectivity (designated by the letter Z) is the amount of transmitted power returned to the radar receiver. The dBZ values increase as returned signal strength increases.
Page 211 Requesting NEXRAD Data NEXRAD data can be requested from the Data Link Page or the Map Page. Requesting NEXRAD data from the Data Link Page: Select the Data Link Page from the AUX Page Group. Press the small right knob to activate the cursor.
Page 212 SECTION 11 ADDITIONAL FEATURES • Auto Request (GDL 49 Only) - This field is used to set the time interval for the GDL 49 to automatically send a NEXRAD data request. The time options are OFF, 10 min, 15 min, 20 min, 30 min, 45 min, and 1 hour.
Page 213 Displaying NEXRAD Data on the Weather Page To display NEXRAD Data on the Weather Page: Select the NAV Weather Page (Figure 11-34) using the small and large right knobs. When the GNC 420 unit is configured with the Data Link interface, the Weather Page is the third page in the NAV Page Group (it is the fourth page if a traffic sensor is also configured).
Page 214 SECTION 11 ADDITIONAL FEATURES Displaying NEXRAD Data on the Map Page When NEXRAD data is received, it is displayed on the Map Page, in addition to the Weather Page and the Default NAV Page. Customizing NEXRAD Data on the Map Page The pilot can customize NEXRAD data on the Map Page by using the Page Menu.
Page 215 The pilot may use the ‘NEXRAD Off?’ and ‘NEXRAD On?’ fields in the Page Menu (Figure 11-36) to turn off the display of NEXRAD data from the Map Page. Figure 11-36 Map Page Options Menu NOTe: if the GNC 420 is configured for Weather Data Link interface with a GDL 49 or GDL 69, pressing the CLR Key while viewing the Map Page reduces the NeXraD density one...
Page 216 SECTION 11 ADDITIONAL FEATURES Data Link Request Log Page (GDL 49 Only) The Data Link Request Log Page (Figure 11-38) is used to display the data that was requested. When a request is received, a check mark is placed in the box. Viewing the Data Link Request Log Page: Use the small and large right knobs and select the Data Link Page from the AUX Group of...
Page 217 • Auto Request - This field is used to set the time interval for the system to automatically send the position. The time options are OFF, 10 min, 15 min, 20 min, 30 min, 45 min, and 1 hr. When an auto request time is selected, the first report is sent after the specified time has elapsed from when the field was set (as opposed to immediately sending a...
Page 218 SECTION 11 ADDITIONAL FEATURES NOTe: Textual MeTars can only be requested by identifier or by flight plan (if the flight plan contains a MeTar station identifier). • Center - This field allows the pilot to specify reference points for the request. The following five options are available for the ‘Center’...
Page 219 Requesting graphical or textual METARs from the Map Page: Select the Map Page. Press the MENU Key. The Map Page Options Menu is displayed (Figure 11-44). Figure 11-44 Map Page Menu Select ‘Request METAR’ and press the ENT Key. The METAR Request Page is displayed. There are four user-selectable parameter fields: Format, Center, Radius, and Position (see preceding pages for detailed information).
Page 220 SECTION 11 ADDITIONAL FEATURES Weather Legend Page The symbology unique to Graphical METAR, Winds, and Temperature/Dewpoint data is displayed on the Weather Legend Page. The Weather Legend is accessed from the Weather Page. NOTe: all MeTar, Wind, and Temp-Dewpoint symbols are depicted at the end of this section. Displaying the Weather Legend: Select the Weather Page and activate the cursor.
Page 221 Entering an identifier: Select the Data Link Page. Highlight ‘TEXTUAL METAR’ and press the ENT Key. Turn the small right knob and scroll through the list of four letter identifiers. Highlight the desired identifier and press the ENT Key. The text box displays the METAR data for the selected identifier.
Page 222 SECTION 11 ADDITIONAL FEATURES Monitoring the Data Link The Data Link Status Page provides an indication of the integrity of the Data Link. The Data Link Page allows the pilot to monitor the system and determine the possible cause of a failure. View the Data Link Status Page: From the AUX Page Group, select the Data Link Page.
Page 223 The GDL 69 Datalink Status Page shows the following fields: • Sat ID/Connectivity - This field shows the current activation status and signal strength of the XM Satellite Radio weather service. Table 11-10 lists the messages that may be shown in the Sat ID field.
Page 224 SECTION 11 ADDITIONAL FEATURES Standard Aviation Forecast Abbreviations The standard aviation forecast abbreviations are listed in Table 11-12. STANDARD AVIATION FORECAST ABBREVIATIONS ‘+’ – (Heavy) ‘-’ – (Light) ‘/’ – (Missing or separator) Axxxx – Altimeter setting (xxxx are numbers) AFT –...
Page 225 Ceiling and Visibility - Flight Rules Marginal VFR (green bars) (green bars) (yellow bars) Table 11-15 Ceiling and Visibility Graphics Ceiling Precipitation Data Age Station Identifier Figure 11-48 METAR Symbol Winds Wind Vector - The wind vector indicates the direction of the surface wind to the nearest 30˚ increment (e.g.
Page 226 SECTION 11 ADDITIONAL FEATURES Temp - Dewpoint Display Ranges (Blank) Table 11-18 Temp-Dewpoint Ranges This symbol in Figure 11-50 displays the difference between the reported temperature and dewpoint as 7-10 degrees Fahrenheit at KSPW. Temperature Dewpoint Figure 11-50 Temp-Dewpoint Symbol 11-36 Unknown 11°+...
Page 227: Section 12: Fault Detection And Exclusion
SECTION 12: FAULT DETECTION AND EXCLUSION Fault Detection and Exclusion (FDE) is incorporated in the Garmin GNC 420 main and GPS software version 3.00 and higher. FDE algorithms provide a basis for approval per the requirements for “GPS as a Primary Means of Navigation for Oceanic/Remote Operations”, FAA Notice...
Page 228: Pre-Departure Verification Of Fde
The trainer software and the document “400/500-series FDE Prediction Instructions” (190-00643-00) are available on Garmin’ s website for free download (www.garmin.com). Figure 12-2 Garmin 400-Series Trainer Software GNC 420(A) Pilot’s Guide and Reference...
Page 229: Section 13: Messages, Abbreviations, And Nav Terms
Or, the data was being received, but has been interrupted. If a grey code altitude input is available, it is used instead. If the problem persists, contact a Garmin dealer and check the installation and installation settings. When this message occurs, no...
Page 230 Garmin dealer for service. The GNC 420 has detected a failure in its communications transceiver. The COM transceiver may still be usable, but the unit should be returned (at earliest convenience) to a Garmin dealer for service.
Page 231 The GNC 420 has detected a problem with the NavData Card. The data is not usable and Data card failure the card should be returned to Jeppesen or to a Garmin dealer. An attempt to transfer flight plan data during a unit-to-unit crossfill was cancelled. The host Data transfer cancelled unit is busy or unable to communicate.
Page 232 The GNC 420 has detected a failure in its GPS receiver. The GPS receiver may still be usable, but the unit should be returned (at the earliest convenience) to a Garmin dealer for service. Satellite almanac, ephemeris and time data have been lost due to a memory battery failure, system reset, or data expiration (data over six months old).
Page 233 Garmin dealer for service. The internal battery that sustains user memory is low and should be replaced by a Garmin Memory battery low dealer as soon as possible. Failure to do so may result in loss of stored data, including flight plans, user waypoints, unit settings, and satellite data.
Page 234 The user-entered scheduler message time has expired, and the scheduler message is displayed. The GNC 420 is searching the sky for GPS satellite almanac data or the GPS receiver is in AutoLocate Mode. Allow the unit to complete data collection (approximately five minutes) before turning it off.
Page 235 The terrain functionality self-test has failed. The operational status of the terrain components Terrain has failed is unknown and the unit should be returned to a Garmin dealer for service. Timer has expired The count down timer has reached zero.
Page 236: Abbreviations
SECTION 13 – MESSAGES, ABBREVIATIONS, & NAV TERMS 13.2 ABBREVIATIONS The following is a list of abbreviations used on the GNC 420 and their meanings: ACTV Active Altitude APPRCHING Approaching Approach Airport ARSPC Airspace ARTCC Air Route Traffic Control Center ARVL Arrival Auxiliary...
Page 237 Glideslope Gallons Global Positioning System Ground Speed Heading Inches of Mercury Horizontal Uncertainty Level Highway Identifier Imperial Gallons Instrument Landing System Indicated Intersection INTEG Integrity Kilograms Kilohertz Kilometers Kilometers Per Hour Knots LAT/LON Latitude/Longitude Pounds Local LFOB Left-over Fuel On Board Localizer LRES Left-over Fuel Reserve Time...
Page 238 SECTION 13 – MESSAGES, ABBREVIATIONS, & NAV TERMS P.POS Present Position PROC Procedure(s) PROV Province Power Radial RAIM Receiver Autonomous Integrity Monitoring Reference Required/Requirements RESTRICTD Restricted Range Receive Standard Instrument Departure Small Speed Squelch SRFC Surface STAR Standard Terminal Arrival Route Special Use Airspace °T Degree True...
Page 239: Navigation Terms
13.3 NAVIGATION TERMS The following navigation terms are used on the GNC 420 and in this Pilot’ s Guide. Refer to Figures 13-1 and 13-2 for graphic representation of navigation terms. NORTH WPT 1 Figure 13-1 Illustrated NAV Terms Term ALT (altitude) Height above mean sea level (MSL).
Page 240 SECTION 13 – MESSAGES, ABBREVIATIONS, & NAV TERMS Term A measure of fuel consumption, expressed in distance per fuel units (e.g., nautical miles per EFF (efficiency) gallon). ENDUR (endurance) Flight endurance, or total available flight time based upon available fuel. EPE (estimated A measure of satellite geometry quality and additional factors, expressed as a horizontal position error)
Page 241: Appendix Adata Card Use
APPENDIX A: DATA CARD USE The Jeppesen NavData Card, and the Terrain Data Card (if applicable) supplied with the GNC 420 can be installed or removed when the GNC 420 is on or off. If the NavData Card is not present when the unit is turned on, a ‘No Jeppesen Aviation Database - Limited to user defined waypoints’...
Page 242 APPENDIX A DATA CARD USE Removing the NavData or Terrain Data Card (Figure A-2): Gently press on the tab—using a slight upward motion—at the front center of the data card. This partially deploys the swing arm handle. Rotate the swing arm handle upward (and outward) until it locks into place, perpendicular to the face of the GNC 420 unit.
Page 243: Appendix B: Specifications
Fuel Sensor; Fuel/Air Data * Earlier versions of the 420 were designed to be used with 28 Vdc power only. For questions on a particular installation, please refer to a Garmin authorized service center. GNC 420(A) Pilot’s Guide and Reference...
Page 244 APPENDIX B SPECIFICATIONS Blank Page GNC 420(A) Pilot’s Guide and Reference 190-00140-20 Rev. K...
Page 245: Appendix C: Troubleshooting Q & A
If, after reading through the appropriate reference section, the answer cannot be found, please see an authorized dealer or contact Garmin directly at the address or phone numbers listed on page ii. Garmin is dedicated to supporting its products and customers.
Page 246 APPENDIX C TROUBLESHOOTING What happens when I select an approach? Can I store a flight plan with an approach, departure, or arrival? When loading an approach, departure, or arrival into the active flight plan, a set of approach, departure, or arrival waypoints is inserted into the flight plan—along with a header line describing the instrument procedure (Figure C-2).
Page 247 NORMAL (no ‘OBS’ annunciator) Automatic sequencing of Manual sequencing- ‘holds’ waypoints on selected waypoint Change in HSI does not Manually select course to affect CDI deflection next waypoint from HSI Always navigates ‘TO’ the Indicates ‘TO’ or ‘FROM’ active waypoint waypoint Must be in this mode for Cannot be set for final...
Page 248 APPENDIX C TROUBLESHOOTING When should I use the OBS key to return to auto sequencing, and what happens when I do? The most common application for using the OBS Key is the missed approach. The GNC 420 suspends automatic waypoint sequencing (indicated by a ‘SUSP’ annunciation directly above the OBS Key;...
Page 249 When does turn anticipation begin, and what bank angle is expected? The GNC 420 smooths adjacent leg transitions based upon a nominal 15º bank angle (with the ability to roll up to 25º) and provide three pilot cues for turn anticipation: 1) A waypoint alert (‘NEXT DTK ###°’) flashes in the lower right corner of the screen 10 seconds before the turn point (Figure C-6).
Page 250 APPENDIX C TROUBLESHOOTING Why does my CDI not respond like a VOR when OBS mode is active? Unlike a VOR, the CDI scale used on GPS equipment is based on the cross-track distance to the desired course, not an angular relationship to the destination (Figure C-8).
Page 251 Abbreviations 7-4, 7-6, 7-8, 7-14, 7-15, 7-16, 13-8 Accessories 1-1 Activate an existing flight plan in reverse 5-4 Activate leg 5-10, 5-15, C-4 Activate the approach 6-4, 6-10, C-6 Activating flight plans 5-3 Active flight plan options 5-8, 5-10, 5-11, 5-12, 5-13 Active frequency 1-9, 2-1, 2-2, 2-5 Active leg 1-12, 3-3, 5-9, 6-7, 6-8, 6-11, 6-13, 6-17, 6-18, 6-21, 6-26, C-4...
Page 252 GDL 49 11-18 GDL 69/69A 11-18 Generic timer 9-15, 9-16 GPS iv GPS receiver status 3-23, 3-24 GPS Window 1-9 Graphic “track” indicator 3-20 Ground speed 1-11, 1-12, 3-3, 3-7, 3-14, 3-20, 3-24, 6-24, 6-26, 9-3, 9-5, 9-7, 9-12, 9-16, 9-17, 13-12...
Page 253 Locked waypoints 13-2 Magnetic variation 7-15, 9-21, 9-24 Main page groups 8-1, 9-1 Manual sequence 6-21, 6-25 MAP (missed approach point) 4-1, 6-3 Map datums 9-20 Map direct-to 3-8 Map orientation 3-10, 3-11 Map Page 1-11, 3-5, 3-6, 3-7, 3-10, 3-14, 4-5, 6-7, 6-8, 6- 13, 6-17, 6-18, 6-24, 7-16, 7-18, 9-20, 13-5 Map page options 3-10 Map panning 3-7...
Page 254 INDEX Radar coverage 7-4 RAIM prediction 9-17 RAIM protection limits 9-18 Reference waypoint 3-20, 3-21, 3-22, 3-26, 5-9, 5-13, 7-16, 7-17, 7-18, 7-20, 7-22 Remove the data card A-2 Removing approaches 5-14 Renaming a user waypoint 7-22 Requesting Graphical METARS 11-27 Request METAR 11-25 Request NEXRAD 11-25 Right-hand keys and knobs 1-3...
Page 255 INDEX Vectors-To-Final 3-3 Vectors-to-final 6-17 Vertical navigation 3-25, 13-1, 13-2, 13-10 VNAV (Vertical Navigation) Page 3-25 Volume 1-3, 1-5, 2-1 VORs 1-11, 1-15, 3-10, 3-16, 4-2, 7-1, 7-15, 8-1, 8-2, 8-7 VOR Page 7-15 VSR (vertical speed required) 3-3, 3-27, 13-10 Warranty vi Waypoint alerts C-5 Waypoint entry 7-2...
Page 256 Blank Page...
Page 258 Hounsdown Business Park Southampton, SO40 9RB, U.K. p: +44/ (0) 870.8501241 f: +44/ (0) 870.8501251 Garmin Corporation No. 68, Jangshu 2nd Road Shijr, Taipei County, Taiwan p: 886/2.2642.9199 f: 886/2.2642.9099 www.garmin.com 190-00140-20 Rev. K © 2009 Garmin Ltd. or its subsidiaries...

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Gnc 420 Gnc 420w

Garmin GNC 420(A) Pilot's Manual & Reference

Section 1: Introduction

Section 2: Com

Section 3: Nav Pages

Section 4: Direct-To Navigation

Section 5: Flight Plans

Section 6: Procedures

Section 7: Wpt Pages

Section 8: Nrst Pages

Section 9: Aux Pages

Section 10: Terrain

Section 11: Additional Features

Section 12: Fault Detection and Exclusion

Section 13: Messages, Abbreviations, and Nav Terms

Appendix Adata Card Use

Appendix B: Specifications

Appendix C: Troubleshooting Q & a

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