250 real 7/14/98 9:31 AM Page i OWNER’S MANUAL & REFERENCE ACTV STBY GNC 250 CLR ENT CRSR SQ NRST RTE WPT NAV MSG TM GNC 250 Pilot’s Guide ®
50 real 7/14/98 9:31 AM Page ii
250 real 7/14/98 9:31 AM Page i INTRODUCTION Foreword Software Version 2.06 or above © 1995 GARMIN International 9875 Widmer Road, Lenexa, KS 66215, USA Romsey House, Station Approach Romsey, Hampshire, UK S051 8DU All rights reserved. No part of this manual may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, for any purpose without the express written permission of GARMIN.
250 real 7/14/98 9:31 AM Page ii INTRODUCTION Cautions CAUTION NOTE: This device complies with Part 15 of the FCC limits for Class B digital devices. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. Furthermore, there is no guarantee that interference will not occur in a particular installation.
250 real 7/14/98 9:31 AM Page iii INTRODUCTION Accessories & Packing List Accessories and Packing List Congratulations on choosing the finest, most advanced panel mount VFR GPSCOM available. The GNC 250 represents GARMIN’s commitment to provide an accurate, easy-to-use GPS for all of your aviation needs. Before installing and getting started with your unit, please check to see that your package includes the following items.
250 real 7/14/98 9:31 AM Page iv INTRODUCTION Warranty Every GARMIN GPS is built to exacting standards to provide years of trouble-free service. GARMIN warrants this product to be free from defects in materials and workmanship for one year from the date of purchase. To obtain warranty service, see your local dealer or call the GARMIN Customer Service department for a returned merchandise tracking number.
250 real 7/14/98 9:31 AM Page v PART ONE: INTRODUCTION INTRODUCTION Table of Contents Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .i Cautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ii Accessories/Packing List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iii Capabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
250 real 7/14/98 9:31 AM Page vi INTRODUCTION Table of Contents Section 6: Messages and Unit Settings ( M key) . . . . . . . . . . . . . . . . . .71 Appendix A: NavData® and User Data Card Use . . . . . . . . . . . . . . . . .81 Appendix B: Installation and Maintenance of the GNC 250 . . . . . . . . . .83 Appendix C: Simulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84 Appendix D: GNC 250 Abbreviations and Messages . . . . . . . . . . . . . . .
250 real 7/14/98 9:31 AM Page vii INTRODUCTION Key and Knob Functions B Q D Key and Knob Functions The power/volume knob controls unit power and radio volume. The squelch button activates automatic squelch control. The direct-to key performs an instant direct-to, allows you to enter a waypoint, and sets a direct course to the destination. T The nearest key is used to obtain information on the 9 nearest airports, VORs, NDBs, intersections, user waypoints and 2 nearest FSSs.
250 real 7/14/98 9:31 AM Page viii INTRODUCTION Key and Knob Functions This manual will describe entering data using the K and O knobs. Experiment with them and become efficient in entering data with the concentric knobs. This will greatly reduce the amount of time required to navigate with the GNC 250. viii M The message key is used to view system messages. The M key is also used to access the GNC 250’s unit settings. See Section 6 for more information on messages and unit settings.
250 real 7/14/98 9:31 AM Page 1 The GARMIN GNC 250 is a powerful navigational tool that provides pilots with accurate navigational data and communication capability, along with a host of database information at your fingertips. The Takeoff Tour is designed to familiarize you with the operation of the GNC 250, including powering up the unit, changing frequencies, entering data and performing a simple direct-to, and a limited introduction to the ‘Nearest’ functions.
250 real 7/14/98 9:31 AM Page 2 TAKEOFF TOUR Acquiring Satellites Once the database has been acknowledged, the satellite status page will appear, and the GNC 250 will begin to collect satellite information. An ‘Acquiring’ status will be displayed on the Satellite Status page, and the signal values on the bottom line of the page will begin displaying numeric values. This is a good indication that you are receiving signals, and satellite lock will occur.
250 real 7/14/98 9:31 AM Page 3 While the GNC 250 is acquiring a position, let’s take a minute to dial in the active and standby frequencies you’ll be using for the first phase of your flight. The GNC 250’s display can be broken down into two separate ‘windows’, the comm window (the top line of the display) and the GPS window (the bottom three lines of the display).
250 real 7/14/98 9:31 AM Page 4 TAKEOFF TOUR Position Page After the GNC 250 acquires satellites and computes a position, the position page will appear automatically, and you’ll be informed with a ‘Ready for navigation’ message on the message page. Altitude, MSA or ESA Position (lat/lon) Reference Waypoint Field The position page displays your present latitude and longitude, altitude and a reference waypoint field.
250 real 7/14/98 9:31 AM Page 5 The GNC 250 uses direct point-to-point navigation to guide you from takeoff to touchdown in the VFR environment. Once a destination is selected, the unit will provide speed, course and distance data based upon a direct course from your present position to your destination. A destination can be selected from any page with the direct-to ( D ) key. TAKEOFF TOUR Direct-To Navigation To select a direct-to destination: 1. Press the D key.
250 real 7/14/98 9:31 AM Page 6 REFERENCE TAKEOFF TOUR Nearest Airport Info & CDI & NAVCOM Pages Navigation Diagram In addition to the destination field and graphical CDI, the GNC 250 CDI page features four selectable fields for various navigation data so that the page may be configured to your own preferences (see Section 1 for more information).
250 real 7/14/98 9:31 AM Page 7 Once a direct-to is activated, the CDI page will provide navigation to the destination until the direct-to is cancelled or another direct-to destination is activated. To cancel a direct-to from the CDI page: TAKEOFF TOUR Cancelling a Direct-To Nearest Waypoints 1. Press the C key twice to activate the cursor in the destination field. 2. Press \. 3. Press E.
250 real 7/14/98 9:31 AM Page 8 REFERENCE TAKEOFF TOUR NearestAcquisition Airports Satellite Shutting Down Once the nearest airport (or any other nearest waypoint) page is displayed, the selected waypoint can be quickly reviewed or selected as a direct-to destination. To review the selected waypoint from the nearest waypoint list: 1. Press C twice to activate the waypoint field. 2. Press E to display the waypoint identification page. 3. Rotate O to view any additional waypoint information available. 4.
250 real 7/14/98 9:31 AM Page 9 REFERENCE NAV KEY Section 1 Navigation Key NAV Overview key overview SECTION 1 The GNC 250 features six navigation pages to provide various position, course, speed, status and planning information. The pages may be viewed by pressing the NAV key and rotating the outer knob, or by pressing the NAV key repeatedly.
250 real 7/14/98 9:31 AM SECTION 1 Page 10 REFERENCE NAV KEY Position Page CDI Page The GNC 250’s CDI page provides you with the important information needed to navigate directly to your destination. The destination field, located at the bottom left of the page, displays the current destination waypoint or active route leg being navigated. If no direct-to destination or route is being navigated, the destination field will remain blank.
7/14/98 9:31 AM Page 11 REFERENCE NAV KEY The following functions may be displayed in the ground speed field: SECTION 1 Proximity Field Configuring the CDI Page • gs— Your present speed over the ground. • str— Steer direction and distance, or digital crosstrack error. An ‘L’ or ‘R’ indicates which direction to steer, while the distance value indicates how far you are off course.
250 real 7/14/98 9:31 AM SECTION 1 Page 12 REFERENCE NAV KEY Waypoint CDI & NAVCOM Pages Communication To change any of the selectable fields on the CDI page: 1. Press C twice to activate the cursor in the GPS window. 2. Rotate O to highlight the field you would like to change. 3. Rotate K to change the field to display the desired information. 4. Rotate O to highlight another field, or C to finish.
250 real 7/14/98 9:31 AM Page 13 If a frequency has sector or altitude restrictions, the frequency will be followed by a ‘brg?’ indication. To view restrictions on a frequency: REFERENCE NAV KEY WaypointPage NAVCOM Communication SECTION 1 1. Press C twice to activate the cursor in the GPS window. 2. Rotate O to highlight the ‘brg?’ next to the frequency you wish to view. 3. Press E to begin viewing restrictions.
250 real 7/14/98 9:32 AM SECTION 1 Page 14 REFERENCE NAV KEY CDI Page Position Page The GNC 250 position page displays your present latitude and longitude, altitude and a reference waypoint field. The altitude and reference waypoint fields are selectable to configure the page to your own preferences and current navigation needs. Altitude, MSA or ESA Position (lat/lon) Reference Waypoint Field Position page displaying MSA.
0 real 7/14/98 9:32 AM Page 15 The position page also features a reference waypoint field, located at the bottom of the page, to indicate your bearing and distance from a selected waypoint.
250 real 7/14/98 9:32 AM SECTION 1 Page 16 REFERENCE NAV KEY NAV Menu 1 & Trip Satellite Status Page Planning The GNC 250’s satellite status page provides satellite information to monitor GPS coverage and receiver performance. This is helpful when you may be experiencing low signal levels due to poor coverage or installation problems. To view the satellite status page: 1. Press N and rotate O until the satellite status page appears.
250 real 7/14/98 9:32 AM Page 17 To change the DOP/EPE field: 1. Press N and rotate O to display the satellite status page. REFERENCE NAV KEY Density Altitude/ Receiver True Air Speed Status Field 2. If the desired field (EPE or DOP) is not displayed, press C twice. SECTION 1 3. Use K to change between ‘epe’ and ‘dop’. Press C to finish.
250 real 7/14/98 9:32 AM SECTION 1 Page 18 REFERENCE NAVPlanning KEY Fuel Satellite Data Page The second and third lines of the satellite status page provide the satellite number and signal strength of each satellite in view. Additional information regarding each satellite’s azimuth, elevation and other data is also available. To view individual satellite information: 1. Press N and use O to display the satellite status page. 2. Press C twice to activate the cursor in the GPS window. 3.
250 real 7/14/98 9:32 AM Page 19 In addition to the other four pages, the GNC 250 features two menu pages to perform a host of planning and navigation functions. NAV Menu 1 provides access to the following functions: • Trip Planning • Density altitude/true air speed calc. • Fuel Planning • Winds aloft calculations • VNAV Planning • Checklists REFERENCE NAV KEY Winds Aloft & NAV Menu 1 VNAV Trip Planning Calculations SECTION 1 To display NAV Menu 1: 1. Press N. 2.
250 real 7/14/98 9:32 AM SECTION 1 Page 20 REFERENCE NAV KEY VNAV Checklists Density&Altitude & True Airspeed The density altitude/true airspeed function is also accessed from NAV Menu 1. Density altitude is the altitude at which your aircraft will perform depending on several environmental conditions, including air pressure and total air temperature (the temperature including the effect of speed, read on a standard outside temperature gauge on most aircraft). True airspeed considers the same factors.
250 real 7/14/98 9:32 AM Page 21 To perform fuel planning operations: 1. Press N and rotate O until NAV Menu 1 is displayed. 2. Press C twice and rotate O until ‘Fuel Plan?’ is highlighted. Press E. REFERENCE NAV KEY SECTION Checklists, NAV NAV Menu 1 Fuel Planning Menu 2& 1 3. Rotate K to select either ‘wpt’ for direct navigation or the desired route number. Press E. 4. For waypoint-waypoint navigation, use K and O to enter the ‘to’ and ‘from’ waypoints. Press E to accept the waypoints.
250 real 7/14/98 9:32 AM SECTION 1 Page 22 REFERENCE NAV KEY Date &Aloft Time, Winds & Trip Timer VNAV Functions The GNC 250’s winds aloft function is used to calculate the true direction and speed of the any winds, and indicates whether you are flying with a head wind or tail wind, and the wind speed. To calculate winds aloft: 1. Press N and rotate O until NAV Menu 1 is displayed. 2. Press C twice and rotate O until ‘Winds?’ is highlighted. Press E. 3.
250 real 7/14/98 9:32 AM Page 23 You will now notice that the vertical speed field has been calculated, based on your present speed. If you desire a more rapid climb or descent: 8. Use K and O to enter the new desired vertical speed, or press E to accept the calculated value. REFERENCE NAV KEY GPS NAVPlanning Menu 1 VNAV & Checklists SECTION 1 9. Press E to activate the vertical navigation function.
250 real 7/14/98 9:32 AM SECTION 1 Page 24 REFERENCE NAV KEY Scheduler, Checklists Sunrise & Timer Sunset Approach To execute a checklist: 1. Press N and rotate O until NAV Menu 1 is displayed. 2. Press C twice and rotate O until ‘Chklist?’ is highlighted. Press E. 3. Use O to highlight the checklist you would like to see. Press E. 4. Press E to check off list items. To delete a checklist item or an entire checklist: 1. To delete a checklist item, highlight the desired item and press \, followed by E.
250 real 7/14/98 9:32 AM Page 25 When the count down timer reaches zero, you will be informed with a ‘Timer expired’ message. The timer will then begin to count up, keeping track of how long it has been since it expired. The timers run, if not altered, anytime the GNC 250 is on.
250 real 7/14/98 9:32 AM SECTION 1 Page 26 REFERENCE NAV KEY CommPrediction Features RAIM Scheduler The RAIM Prediction function allows you to confirm that GPS coverage is available for a specific location or waypoint any day of the year. Receiver Autonomous Integrity Monitoring performs checks to ensure that the GNC 250 will have adequate satellite geometry to work with during your flight. RAIM availability will be near 100% in Oceanic, En route and Terminal phases of flight.
250 real 7/14/98 9:32 AM Page 27 The scheduler function will display reminder messages after a certain elapsed time such as Change oil, Switch fuel tanks, Overhaul, etc. For example, if you enter ‘Change Oil’ to be displayed in 30 hours, the message ‘Change Oil’ will be displayed after the GNC 250 has been on in Normal operating mode for 30 hours. After appearing, the message will be displayed each time the GNC 250 is turned on until it is changed or deleted.
250 real 7/14/98 9:32 AM SECTION 1 Page 28 NAV KEY Sunrise/Sunset Calculations The GNC 250’s sunrise/sunset planning function allows you to calculate the time of sunrise or sunset at any waypoint or your present position for a specified date. To calculate sunrise and sunset times at a waypoint or at your present location: 1. Press N and rotate O until NAV Menu 2 is displayed. 2. Press C twice and rotate O to highlight ‘Sunrise?’. Press E. 3.
250 real 7/14/98 9:32 AM Page 29 Section 2 Communicating with the GNC 250 REFERENCE COMM FEATURES SECTION Waypoint Overview Information 2 The GNC 250 features a digital VHF radio that provides a seamless transition from communication to navigation, bringing the two most important functions in flying together in one panel-mount unit. The GNC 250 operates in the aviation voice band, from 118.000 to 136.975 MHz, in 25 kHz steps.
250 real 7/14/98 9:32 AM SECTION 2 Page 30 REFERENCE COMM FEATURES Entering Waypoints Overview/ Auto-Tuning During the course of navigating with the GNC 250, there may be times when you need to quickly select a comm frequency while you are entering data in the GPS window. Whenever data entry in the GPS window is interrupted by activating the standby frequency field, the GPS field in use will become ‘splatted’, or blocked out. To auto-tune from the nearest airport page, press ENT.
250 real 7/14/98 9:32 AM Page 31 To auto-tune a frequency from a list displayed in the GPS window: 1. Press C twice to activate the cursor in the GPS window. 2. Rotate O to highlight the desired frequency. REFERENCE COMM FEATURES Airport Auto-Tuning/ Volume & Squelch Information SECTION 2 3. Press E to make the selected frequency the standby frequency.
250 real 7/14/98 9:32 AM SECTION 2 Page 32 COMM FEATURES Emergency Channel Selection The emergency channel will appear in the active field. The GNC 250’s emergency channel select feature provides a quick method of selecting the 121.5 MHz frequency as the active frequency in the event of an in-flight emergency. The emergency channel select is available whenever the unit is on, regardless of GPS or cursor status, or loss of the display. To automatically tune for emergency transmission: 1.
250 real 7/14/98 9:32 AM Page 33 Section 3 Waypoint and Database Information REFERENCE WPT KEY SECTION Airport Overview Communication 3 The GNC 250 uses a Jeppesen NavData® card to provide position and facility information for thousands of airports, VORs, NDBs and intersections. Each facility in the database is stored as a waypoint with its own latitude/longitude, identifier (up to five letters and/or numbers), and other pertinent information.
250 real 7/14/98 9:32 AM Page 34 SECTION REFERENCE WPT KEY 3 Waypoint AirportCategories Runway Information & Menu Page The GNC 250 organizes waypoints into one of five waypoint categories for your convenience. Each waypoint category provides different types of detailed information for a selected facility: • Airports - Identifier, city/state, country, facility name, position (lat/lon), elevation, fuel services and communications frequencies.
250 real 7/14/98 9:32 AM Page 35 After a waypoint category is selected, information for a waypoint may be viewed by entering the identifier or name of the desired waypoint. Airports, VORs and NDBs may be entered by either the identifier, name or the location (city) of the facility. Intersections and user waypoints must be entered by the identifier. REFERENCE WPT KEY VOR Information Entering Waypoints SECTION 3 To enter a waypoint identifier: 1.
250 real 7/14/98 9:32 AM SECTION 3 Page 36 REFERENCE WPT KEY VOR Position Page Airport Information Once a waypoint category and identifier have been selected, the GNC 250 will provide extensive information through a set of waypoint pages for the selected category. We’ll now go through the pages available for each waypoint category in the order they appear on the waypoint menu page: airports, VORs, NDBs, intersections and user waypoints.
250 real 7/14/98 9:32 AM Page 37 REFERENCE WPT KEY The GNC 250 features five airport pages: airport identification— allows entry of desired airport by identifier, facility name or city; displays region and/or country of facility. Airport Pages NDB Information SECTION 3 airport position— allows entry of desired airport by identifier; displays latitude, longitude and elevation; indicates usage and fuel availability; displays available approaches and airport control/radar capability.
250 real 7/14/98 9:32 AM Page 38 REFERENCE WPT KEY SECTION 3 The airport position page displays the latitude, longitude and elevation of the selected airport, as well as usage or fuel availability, available approaches and airport control/radar capability. The following descriptions and abbreviations are used on the airport position page: Airport & Intersections Position Page User Waypoints 1 2 Elevation— In feet or meters Usage/Fuel— If the airport is for military use, it will display ‘military’.
250 real 7/14/98 9:32 AM Page 39 The airport communication page displays the radio frequencies and usage for the selected airport, as well as sector and altitude restrictions. To view the communication page from any of the airport information pages: REFERENCE WPT KEY User Airport Waypoints Communications Page SECTION 3 1. Rotate O with the flashing cursor removed to display the communication page. 2. Rotate K in the direction of the arrow prompt to view additional frequencies.
250 real 7/14/98 9:32 AM SECTION 3 Page 40 REFERENCE WPT KEY Autostore Airport™ & User Comments Runway Page The airport runway page displays runway designations, length, surface and lighting for the selected airport, as well as ILS/localizer and/or pilot-controlled lighting frequencies. To view the runway page from any of the airport information pages: 1. Rotate O with the flashing cursor removed to display the runway page. 2.
250 real 7/14/98 9:32 AM Page 41 VOR Information The GNC 250 features three VOR waypoint pages: REFERENCE WPT KEY Proximity VOR Information Waypoints SECTION 3 VOR identification— allows entry of desired VOR by identifier, facility name or city; displays region and/or country of facility. VOR position— allows entry of desired VOR by identifier; displays latitude, longitude and frequency; provides magnetic variation, weather broadcasts and DME/TACAN information.
250 real 7/14/98 9:32 AM SECTION 3 Page 42 REFERENCE WPT Waypoints KEY Proximity NDB Information NDB Information & NDB Position Page The GNC 250 also uses identification, position and comments pages for NDB information. The NDB waypoint pages are used in the same manner as VOR pages: NDB information is accessed by entering the desired facility’s identifier, city or name (see page 35) on the NDB identification page. To scroll through the NDB pages: NDB Identification Page 1.
250 real 7/14/98 9:32 AM Page 43 Intersection Information REFERENCE WPT KEY UserIntersection Waypoints & Waypoint Information Comment Catalog SECTION 3 Intersection Position Page The last database waypoint category available is intersections. Two intersection pages are available: intersection position and intersection comments. Intersections may be entered by identifier only (not city or name) on either intersection page. To scroll through the Intersection pages: 1.
250 real 7/14/98 9:32 AM SECTION 3 Page 44 REFERENCE WPT &KEYLocked Duplicate User Waypoint Information User Waypoints Waypoints In addition to the airport, VOR, NDB and intersection waypoints contained in your NavData® card, the GNC 250 allows you to store up to 1,000 user-defined waypoints.
250 real 7/14/98 9:32 AM Page 45 If the waypoint identifier entered does not exist in the database, you will be prompted to select a method to enter the new waypoint’s position into the database. If the waypoint exists (you’re just reviewing or editing a user waypoint), skip step 4 and move on to the next set of instructions. REFERENCE WPT KEY Route Overview Creating User Waypoints SECTION 3 4. Select the desired waypoint entry method using O and press E.
250 real 7/14/98 9:32 AM SECTION 3 Page 46 REFERENCE WPT KEY Route Information Reference Waypoints To enter/edit a user waypoint position from a reference waypoint: 1. Use K and O to enter the reference waypoint’s identifier. 2. Press E. The waypoint’s position will appear. 3. Use K and O to enter the bearing from the reference waypoint. 4. Press E. 5. Use K and O to enter the distance from the reference waypoint. 6. Press E. The latitude and longitude will be calculated for the waypoint. 7.
250 real 7/14/98 9:32 AM Page 47 The GNC 250’s AutoStoreTM function provides another method of creating user waypoints. AutoStore is used to instantly capture your present position as a user waypoint with a touch of a button and add the new waypoint to the end of a specified route if desired. REFERENCE WPT KEY Route Information Creating Waypoints with AutoStore SECTION 3 To perform an AutoStore: 1. Press N and rotate O to display the position page. 2. Press E.
250 real 7/14/98 9:32 AM SECTION 3 Page 48 REFERENCE WPT KEY Editing Routes Proximity Waypoints The second page available from the GNC 250’s WPT key is the proximity waypoints page. This page allows you to define an alarm circle around a selected waypoint and is useful in defining alarm circles around towers or obstructions. Up to nine proximity waypoints can be entered, with an alarm radius of up to 99.9 nm. To create or edit a proximity waypoint: 1.
250 real 7/14/98 9:32 AM Page 49 The third page available from the GNC 250’s WPT key is the user waypoint list, which can be used to quickly scan, review, rename or delete user waypoints. To display the user waypoint list: REFERENCE WPT KEY Route Copying and User Waypoint List Closest Pt of Approach (CPA) SECTION 3 1. Press W and use O to display the user waypoint list. 2. To scroll through the list, rotate K.
250 real 7/14/98 9:32 AM SECTION 3 Page 50 REFERENCE WPTDiagram KEY CPA Waypoint Comments The last page available through the GNC 250’s WPT key is the waypoint comments page, which lists all waypoints that have a user comment. User comments may be added to 250 waypoints stored in the user or NavData® database, and allow you to note two lines of special information concerning a particular waypoint. To enter user comments: 1.
250 real 7/14/98 9:32 AM Page 51 The GNC 250’s extensive waypoint database makes it possible for several waypoints to share the same identifier. To ensure that you are selecting the waypoint desired, the GNC 250 will always offer the waypoint confirmation page (which shows the waypoint’s position) when an identifier is entered for a particular function. REFERENCE WPT KEY Search and Rescue Waypoint Confirmation Operations Duplicate Waypoints SECTION 3 To accept the waypoint position: 1.
250 real 7/14/98 9:32 AM Page 52 SECTION REFERENCE WPT KEY 3 User Comments & Locked Waypoints Parallel Track Waypoint Scanning Because the GNC 250 relies on a NavData card for most waypoint information, there may be instances when waypoint information is not available for use. Locked waypoints exist when a waypoint contained in a route or used as a proximity waypoint is not contained on the NavData card, or no card is inserted in the unit.
250 real 7/14/98 9:32 AM Page 53 The GNC 250’s NRST key provides detailed information on the nine nearest airports, VORs, NDBs, intersections and user waypoints within 200 nm of your current position. In addition, it will display the two nearest Flight Service Station (FSS) points of communication and alert you to any Special Use Airspace (SUA) you may be in or near.
250 real 7/14/98 9:32 AM SECTION 4 Page 54 REFERENCE NRST KEY Special SpecialUse UseAirspace Airspace The next page available under the GNC 250’s NRST key is the SUA alert page. The SUA alert page will alert you with up to nine controlled or restricted airspaces near or in your flight path, according to the following conditions: • If your projected course will take you inside an SUA within the next 10 minutes, the message ‘SUA ahead < 10 min’ will be displayed.
250 real 7/14/98 9:32 AM Page 55 REFERENCE NRST KEY The SUA alert page contains the following information: SUA Information Special Use Airspace Alert type SUA number 4 ETE (if applicable) SUA Name or controlling agency Controlling airport identifier SECTION SUA type SUA Ceiling altitude SUA Floor altitude The ‘SUA number’ field displays which SUA you are viewing (you may be alerted with up to nine SUAs).
250 real 7/14/98 9:32 AM SECTION 4 Page 56 REFERENCE NRSTandKEY SUAs other SUA Messages Nearest Waypoints SUA Alert Page Frequency information for SUA.
250 real 7/14/98 9:32 AM Page 57 APPENDIX NRST KEYA Special List Unit Settings Use Airspace SECTION 4 SUA Settings Page All SUA alert messages except for prohibited areas may be turned on or off through the GNC 250’s unit settings options, found under the MSG key (see page 77). Alerts for prohibited areas will always be displayed, regardless of unit settings or operating mode. SUA alerts may be turned off so the pilot can avoid continuous alerts in areas with extensive special use airspace.
250 real 7/14/98 9:32 AM SECTION 5 Page 58 APPENDIX A DIRECT-TO Current Messages & ROUTE NAV & Section 5 Direct-to & Route Navigation One of the many benefits of GPS navigation is the ability to fly directly to a waypoint or fly a chain of waypoints without using ground-based navigation aids. To take advantage of the convenience and efficiency provided by point-to-point GPS navigation, the GNC 250 provides two basic methods of selecting a destination for your flight: direct-to and route navigation.
250 real 7/14/98 9:32 AM Page 59 The GNC 250’s direct-to function provides a quick method of setting a course to a destination waypoint. Once a direct-to destination is activated, the GNC 250 will establish a point-to-point route line along the great circle from your present position to the destination and provide steering guidance and navigation data to the waypoint until it is cancelled.
250 real 7/14/98 9:32 AM SECTION 5 Page 60 APPENDIX A DIRECT-TO CDI ScaleSelecting Settings Manually A Course Whenever you perform a direct-to, the GNC 250 will set a point-to-point great circle course to your destination. You can also manually define the magnetic course to your destination with the GNC 250’s course select feature. The course select feature is available from the bottom line of the direct-to confirmation page and works like selecting your desired course on a VOR indicator.
250 real 7/14/98 9:32 AM Page 61 APPENDIX ROUTESA The GNC 250 lets you create up to 20 routes (numbered 0 through 19), with up to 31 waypoints each. Routes are created, copied and edited through the R key, which features two route pages selectable from the GNC 250’s outer knob: the active route page and the route catalog page. The active route page provides information and editing functions for Route 0, which always serves as the route you are currently navigating.
250 real 7/14/98 9:32 AM SECTION 5 Page 62 APPENDIX A ROUTES Creating & Magnetic Variation Editing&Routes Arrival Alarm The route action field, located at the top right of the page, is used to select the desired route operation.
250 real 7/14/98 9:32 AM Page 63 To delete a waypoint: 1. Rotate O to highlight the waypoint you wish to delete. 2. Press \ to remove the name, then press E to delete. APPENDIX ROUTESA Runway Length Deleting && Display Timeout Activating Routes SECTION 5 3. Repeat steps 1 and 2 to delete additional waypoints, or press C to finish. To delete an entire route: 1. Use K to display the route number you would like to delete (route 0 for the active route). 2.
250 real 7/14/98 9:33 AM APPENDIX A ROUTES SECTION 5 Page 64 The route action field also features a copy function that permits you to copy any route to another open storage route. The copy function can be used to save the contents of the active route (route 0) to an open storage route. Display Intensity Copying Routes & Trip Timer CPA Function To copy a route: 1. Press R and use O to display the route catalog page. 2. Use K to display the route to which you would like to copy to.
250 real 7/14/98 9:33 AM Page 65 APPENDIX A ROUTES Navigation Units The GNC 250’s search and rescue function provides navigation guidance for search and rescue operations, navigating in a ladder pattern to maximize coverage and efficiency. This is done in reference to two waypoints called ‘anchor waypoints’. The first leg will be a specified distance from the line connecting the anchor waypoints. This is called the ‘offset distance’. The ‘increment distance’ is the distance between each subsequent leg.
250 real 7/14/98 9:33 AM APPENDIX ROUTES A SECTION 5 Page 66 Parallel Track SUA Settings Offset Navigation Enter parallel track value after route activation. ARRIVAL WAYPOINT During route navigation, it is sometimes desirable to navigate a specified distance away from the ‘active leg’ to help avoid certain airspaces or regions. The GNC 250’s parallel track feature will automatically guide you along a selected offset from the active leg.
250 real 7/14/98 9:33 AM Page 67 Flying and Modifying the Active Route Once a route has been created and activated, the GNC 250 will provide navigation to each route waypoint through the active route and CDI pages. From the active route page, you may also create and modify the active route. The CDI page will display detailed navigation data on your progress to each route waypoint and provide turn anticipation, waypoint arrival and next desired track information.
250 real 7/14/98 9:33 AM SECTION 5 Page 68 APPENDIX A ROUTES Active Page DataRoute Transfer Inserting Waypoints The leg field can be selected to display cumulative distance or the distance for each route leg. If cumulative is selected, the first leg’s distance will be displayed. The second leg will represent the first leg’s distance plus the second leg, and so on.
250 real 7/14/98 9:33 AM Page 69 To delete a waypoint from the active route: 1. Press C twice, if necessary, to activate the cursor. APPENDIX ROUTESB NavData & On-Route Direct-To User Data Cards Waypoint Sequencing SECTION 5 2. Use O to highlight the waypoint you would like to delete from the active route. 3. Press \, followed by E. The next route waypoint (if available) will move up to take the position of the deleted waypoint.
250 real 7/14/98 9:33 AM SECTION 5 Page 70 APPENDIX B ROUTES UserWaypoint Data Transfer Sequencing To ‘hold’ on the active-to waypoint: 1. Press D. The direct-to confirmation page will appear. 2. Rotate O to highlight the waypoint sequencing field, and rotate K to select ‘hold’. 3. Press E. The cursor will advance to the course select field where you may manually enter the desired course to the ‘hold’ waypoint. The default course is the GPS course calculated from your present position. 4.
250 real 7/14/98 9:33 AM Page 71 Section 6 Messages and Unit Settings APPENDIX C UNIT SETTINGS Installation, Messages & Settings Submenus Removal & SECTION 6 The GNC 250’s MSG key provides access to system messages and allows you to customize your GPSCOM to your own preferences through a settings submenu. Whenever the GNC 250 needs to alert you to a navigation, communication or system message, the annunciator light next to the M key will flash. Some messages are advisory in nature (e.g.
250 real 7/14/98 9:33 AM SECTION 6 Page 72 APPENDIX C UNIT SETTINGS CDI Settings Maintenance Magnetic Variation To change the CDI scale: 1. Press and hold M, and rotate O to select the ‘CDI Settings’ page. 2. Press C twice and rotate K to select ‘Auto’, ‘+- 5.0 nm’, ‘+- 1.0 nm’ or ‘+- 0.3 nm’. 3. Rotate O to highlight ‘ok?’ and press E to approve. Note: the selected CDI scale will not take effect until approved. The scale values represent full scale deflection of the CDI to either side.
250 real 7/14/98 9:33 AM Page 73 If ‘auto’ mag var is selected, all track, course and heading information will be corrected with the variation computed by the GPS. The ‘true’ setting will reference all information to true north, and the ‘user’ setting will correct information to an entered value.
250 real 7/14/98 9:33 AM SECTION 6 Page 74 APPENDIX D UNIT SETTINGS Battery Saver Messages & Display Intensity Abbreviations The GNC 250’s battery saver feature can be programmed to automatically turn off the display when using the optional remote battery pack. This will increase the remote battery life in event of power failure. During this time, the GNC 250 will continue to navigate and track satellites, but will not display information until a key is pressed or a knob is turned.
250 real 7/14/98 9:33 AM Page 75 The trip timer provides a running clock on NAV Menu 2 (see page 25), and can be configured to run when power is on or when your ground speed exceeds a user-defined minimum. APPENDIX D UNIT SETTINGS Trip Timer Messages & Abbreviations Units of Measure SECTION 6 To change the trip timer settings: 1. Press and hold M, and use O to display the trip timer settings page. 2. Press C twice to activate the cursor. 3. Use K to select either ‘pwr is on’ or ‘gs exceeds’. 4.
250 real 7/14/98 9:33 AM SECTION 6 Page 76 APPENDIX D UNIT SETTINGS Messages & Units of Measure Abbreviations The available units of measure are: position : • degrees, minutes and seconds (dms) [hddd° mm’ ss.s”] • degrees and minutes (dm) [hddd° mm.mmm’] altitude : • feet (ft) vertical speed : • feet per minute (fpm) • meters per second (mps) Units of Measure Settings (metric).
250 real 7/14/98 9:33 AM Page 77 The Special Use Airspace settings page will allow you turn the controlled/restricted airspace message alerts on or off. This will not affect the alerts being listed on the nearest page. It will simply turn off the warning when you are approaching or near an SUA.
250 real 7/14/98 9:33 AM SECTION 6 Page 78 UNIT SETTINGS Map Datums The GNC 250 NavData® card contains over 100 map datums for you to use when navigating. By default, your unit calculates positions using the WGS-84 map datum. If you are using charts based on another datum, you must set the GNC 250 to use the same datum. Using a map datum that does not match the sectionals you are using can result in significant differences in position information.
250 real 7/14/98 9:33 AM Page 79 The last page available under the GNC 250’s setup menu is the I/O setup page. The I/O setup page lets you configure the GNC 250 to output to a RS-232 mapping device or a PC (with the optional GARMIN PC Kit or other mapping software) and select the appropriate baud rate. The I/O setup page only provides access to I/O channel 2 output. For information on using I/O channel 1, please see your GNC 250 installation manual.
250 real 80 7/14/98 9:33 AM Page 80
250 real 7/14/98 9:33 AM Page 81 Appendix A NavData® and User Data Installation and Operation NAVDATA CARD SECTION Saving User Data A The NavData card supplied with your GNC 250 can be installed or removed when the GNC 250 is on or off. Insert the card with the thumb tab at the top, and the beveled corner at the bottom.
250 real 7/14/98 9:33 AM SECTION A Page 82 NAVDATA CARD Saving User Data To restore user data from a user data card to the GNC 250: 1. Install the user data card. 2. Rotate O to highlight ‘Restore user data?’. 3. Press E. The GNC 250 will ask you which type of data to replace. You may choose checklists, scheduler messages, user waypoints, proximity waypoints, routes, waypoint comments, or all data. 4. Rotate K to select the type of data to replace.
250 real 7/14/98 9:33 AM Page 83 Appendix B Installation, Removal and Maintenance of the GNC 250 INSTALLATION & MAINTENANCE SECTION B The aviation rack is designed to allow easy removal of the GNC 250. This enables you to use the unit at home to create routes, interface to a PC, etc. using an optional AC adapter. To install the GNC 250 into the aviation rack: 1. Insert a 3/32” allen wrench in the small hole adjacent to the dual knob. 2.
250 real 7/14/98 9:33 AM SECTION C Page 84 SIMULATOR The GNC 250’s simulator mode allows you to plan and practice flights in your home and office using an optional remote battery pack or AC adapter. The simulator is not accessible when the GNC 250 is running off the master avionics switch. All waypoint and route planning done in simulator mode will be saved in the unit’s internal memory. To operate the GNC 250 in simulator mode: 1.Turn the unit on by rotating the B knob clockwise.
250 real 7/14/98 9:33 AM Page 85 To enter an initial position reference by waypoint identifier: SIMULATOR 1.Rotate O to highlight the waypoint identifier field. SECTION C 2. Use K and O to spell out the identifier of the desired airport, navaid or user waypoint. 3. Press E to confirm the identifier. The waypoint confirmation page will appear, displaying the waypoint’s position. 4. Press E to confirm the ‘ok?’ prompt.
250 real 7/14/98 9:33 AM SECTION D Page 86 MESSAGES & ABBREVIATIONS Appendix D GNC 250 Messages and Abbreviations The GNC 250 uses the Message Page to communicate important information to you. Some messages are advisory in nature, others are warnings that may require your intervention. This appendix provides a complete list of GNC 250 messages and their meanings.
250 real 7/14/98 9:33 AM Page 87 Comment memory full - The waypoint comment memory is full. You must delete existing waypoint comments before adding new ones. Configuration reset - The GNC 250 has detected a failure in its installation configuration memory. Data from the user memory has been used to reset the configuration. Check the installation settings for correctness. If the message persists, the unit is not usable and should be taken to an authorized service center for repair.
250 real 7/14/98 9:33 AM SECTION D Page 88 MESSAGES & ABBREVIATIONS Offset nav in effect Ofst too big for rte Osc needs adjustment Poor GPS coverage Prox alarm-press NAV Leg not smoothed Memory battery low Near SUA < 2 nm Need alt - press NAV Offset nav cancelled 88 - The upcoming leg is too short for smooth waypoint transitions. Expect a rapid change in the CDI. - The battery that sustains user memory is low and should be replaced by an authorized GARMIN service center as soon as possible.
250 real 7/14/98 9:33 AM Page 89 - The GNC 250 is unable to cross-check its position using RAIM. You may continue to navigate using visual flight rules. Your position should be verified every 15 minutes using other navigation sources. If you have selected a CDI scale other than ‘Auto’, selecting a larger CDI scale may remove the conditions causing this message. RAIM position warn - RAIM has detected position errors.
250 real 7/14/98 9:33 AM SECTION D APPENDIX D MESSAGES & Messages & ABBREVIATIONS Abbreviations Searching the sky Start altitude chng Steep turn ahead Stored data lost Stuck mic/tx disabled 90 Page 90 - The GNC 250 is in the search-the-sky mode. Allow the unit to complete data collection before turning it off. - The altitude change entered on the VNAV Planning page is about to begin.
250 real 7/14/98 9:33 AM Page 91 This section of Appendix D provides a complete list of GNC 250 abbreviations and their meanings.
250 real 7/14/98 9:33 AM SECTION D 92 Page 92 APPENDIX D MESSAGES & Messages & ABBREVIATIONS Abbreviations JET A- Jet Fuel - Type A JET B- Jet Fuel - Type B KHKilometers Per Hour KMKilometers KTKnots LBPounds LCLLocal LENLength LFOB- Leftover Fuel On Board LFLOW- Left Fuel Flow LOCLocalizer LTLiters MAG VAR-Magnetic Variation MBMillibars Of Pressure MFMandatory Frequency MHStatute Miles Per Hour MIStatute Miles MICMicrophone MINMinimum MIN - Minutes MOA- Military Operations Area MPM- Meters Per Minut
250 real 7/14/98 9:33 AM RTERXSARSECSEQSGLSLCTSRFCSTRTACANTASTAT TEMPTMATRKTRNTRSATWRTXUUNIURAUSER- Page 93 Route Receive Only Search And Rescue Seconds Sequence Signal Select Surface Steer To TACtical Air Navigational Aid True Airspeed Total Air Temperature Temperature ICAO Terminal Control Area Track Angle Turn Angle Terminal Radar Service Area Tower Transmit Only UTC Time Unicom User Range Accuracy User Waypoint USRUTCVNVNAVVORWPTWXXFR- User Waypoint Universal Time Coordinated (GMT/ Zulu) VNAV or V
250 real 7/14/98 9:33 AM SECTION E Page 94 APPENDIX F Map Datums SPECIFICATIONS Appendix E Specifications PHYSICAL Size: Weight: Rack Size: Rack Weight: 6.25”W x 5.8”D x 2”H (159mm x 147mm x 51mm) 39 ounces (1.11kg) 6.32”W x 5.64”D x 2”H (161mm x 143mm x 51mm) 11 ounces (0.31kg) POWER Input: ** Subject to accuracy degradation to 100m 2DRMS under the US DOD-imposed Selective Availability Program.
250 real 7/14/98 9:33 AM Page 95 APPENDIX F MAP DATUMS Map Datums Appendix F Map Datums ADINDAN Ethiopia, Mali, Senegal, Sudan AFGOOYE Somalia AIN EL ABD 1970 Bahrain Island, Saudi Arabia ANNA 1 ASTRO 1965 Cocos Islands ARC 1950 Botswana, Lesotho, Malawi, Swaziland, Zaire, Zambia, Zimbabwe ARC 1960 Kenya, Tanzania ASCENSION IS 1958 Ascension Island ASTRO B4 SOROL ATOLL Tern Island ASTRO BEACON “E” Iwo Jima Island ASTRO DOS 71/4 St.
250 real 7/14/98 9:33 AM SECTION F Page 96 APPENDIX F MapDATUMS Datums MAP LUZON PHILIPPINES MAHE 1971 MARCO ASTRO MASSAWA MERCHICH MIDWAY ASTRO 1961 MINNA NAD27 ALASKA NAD27 BAHAMAS NAD27 CANADA NAD27 CANAL ZONE NAD27 CARIBBEAN NAD27 CENTRL AMERICA NAD27 CONUS NAD27 CUBA NAD27 GREENLAND NAD27 MEXICO NAD27 SAN SALVADR IS NAD83 NAHRWAN MASIRAH IS NAHRWAN SAUDI ARABIA NAHRWAN UNITD ARAB E NAPARIMA BWI NETHERLAND TRIAG ‘21 NOU TRIAG FRANCE NOU TRIAG LUXEMBOURG OBSERVATORIO 1966 96 OLD EGYPTIAN OLD HA
250 real 7/14/98 9:33 AM Page 97 Appendix G Index A Abbreviations Accessory list Activating a direct-to Activating a route Activating a route in reverse Active frequency Active to & from waypoints Active route page Adding waypoints to a route Airport comments page Airport communications page Airport runway page Airport position page Airport identification page Airport information Altitude buffer Approach information Approach timer Arrival alarm setting AutoStore™ Auto-tune B Battery Pack Battery saver C
250 real 7/14/98 9:33 AM SECTION G Page 98 APPENDIX G Index INDEX E Editing routes Editing user waypoints ENT key Entering waypoints EPE Emergency channel select F Foreword Flying the active route Fuel planning G Going to a nearest airport GPS planning Ground speed (setting) i 67-70 20, 21 53 26 85 I Inner knob Initial position reference page Installation of the GNC 250 Intersections I/O Outputs viii 84-85 83 34, 43 72 K Key functions Knob functions vii,viii vii,viii L Leg/time field Locked way
250 real 7/14/98 9:33 AM Page 99 R RAIM prediction RAIM protection Radar information Receiver status Removal of the GNC 250 Renaming user waypoints Restoring user data Reversing a route Route catalog page Route comments Route key Route navigation Routes Runway page Runway surface 26 72 38 16-17 83 47,49 81-82 63 61 61 vii 58 61-70 40 40, 73 S Satellite acquisition Scheduler Search and rescue operations Simulator mode Special Use Airspace (SUA) Specifications Standby frequency Storing user data SUA aler
250 real 7/14/98 9:33 AM SECTION G 100 Page 100 APPENDIX G Index INDEX Waypoint scanning Waypoint sequencing Waypoints with comments Winds aloft 52 69-70 50 22
250 real 7/14/98 9:33 AM Page 101
250 real 7/14/98 9:33 AM Page 102 ® © 1995 GARMIN International 9875 Widmer, Lenexa, KS 66215, USA GARMIN/Europe LTD Robert House, Station Approach Romsey, Hampshire SO51 8DU UK Part No. 190-00067-50 Rev.
