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Garmin GDL 90 Installation Manual

Uat data link sensor
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GDL 90 UAT Data Link Sensor
Installation Manual
October 2006
560-1049-02 Rev. B

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  • Page 1 GDL 90 UAT Data Link Sensor Installation Manual October 2006 560-1049-02 Rev. B...
  • Page 2 Garmin. Garmin hereby grants permission to download a single copy of this manual and of any revision to this manual onto a hard drive or other electronic storage medium to be viewed for...
  • Page 3 §1.3.7.1: Update the list of approved GPS antennas. §1.4.3: Added list of TSO deviations. §2.6.1: Clarify the required GPS cable loss, and that the GDL 90 is not compatible with SATCOM equipment. Clarified note regarding use of existing GPS antennas.
  • Page 4 2-12 A 5-3 2-13 A 5-4 2-14 A 5-5 2-15 A 5-6 2-16 2-17 A 6-1 2-18 A 6-2 2-19 2-20 B A-1 2-21 A A-2 2-22 A A-3 2-23 A A-4 2-24 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 5: Table Of Contents

    1.4.2 TSO A ..........................1-8 UTHORIZATION 1.4.3 TSO D .............................1-8 EVIATIONS 1.4.4 FCC G ..................1-8 RANT OF QUIPMENT UTHORIZATION 1.4.5 GDL 90 STC A .........................1-8 UTHORIZATION ........................1-9 NPACKING THE QUIPMENT ............................1-9 ACKAGE ONTENTS & A ........................1-10 EFINITIONS CRONYMS ..............................2-1 NSTALLATION ........................2-1...
  • Page 6 1-4. I (PN 424-6081-100) .............1-10 ABLE PTIONAL ARTS 1-5. O ........................1-10 ABLE RIMP OOL FOR 2-1. C P/N 245-0027 .....................2-2 ABLE NTERFACE ONNECTORS 2-2. I .....................2-11 ABLE RIMP ONTACT PECIFICATIONS 2-3. C ..................2-11 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 7 4-2. D ....................4-4 ABLE TEMS FOR INITIALIZATION 4-3. D .................4-9 ABLE ORKSHEET 4-4. APM W ........................4-15 ABLE NSTALLATION HECKOUT 4-5. GDL 90 P ..............4-20 ABLE ROUBLESHOOTING UIDE 5-1. T .....................5-1 ABLE TATIC D-1. S .......................D-1 List of Illustrations IGURE YPICAL...
  • Page 8 Table of Contents Notes 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 9: General Information

    The information in this manual is STC approved. Only the equipment interfaces covered in this manual are within the scope of this STC. Other equipment may be suitable for use with the GDL 90, but use of such equipment is beyond the scope of this STC – additional FAA approval may be required if equipment not covered in this manual is used to interface to the GDL 90.

  • Page 10: Equipment Description

    The Garmin GDL 90 is a remote-mounted product that contains a GPS/WAAS receiver and a Universal Access Transceiver. The GDL 90 will transmit ownship data via the UAT data link. It will receive data from other UAT-equipped aircraft, as well as FIS-B weather – the received data may be output to an appropriate display.
  • Page 11 The GDL 90 can connect to an altitude encoder to obtain pressure altitude data via an RS-232 or ARINC 429 bus. 1.2.2.3 Control Panel The GDL 90 can connect to an optional Control Panel unit (such as the GSL 71), or certain models of transponder via an RS-232 bus. 1.2.2.4 Annunciator Outputs and Switch Inputs The GDL 90 can drive one external annunciator lamp and receive inputs from various switches to control its operation.

  • Page 12: Specifications

    1.2 lb (0.54 kg) mounting tray only 1.3.3 Environmental The GDL 90 is designed and tested to meet appropriate categories as shown in the Environmental Qualification Form included in Appendix A. Operating temperature........-20 C to +55 C Storage temperature ........-55 C to +85 C Temperature variation ........

  • Page 13: Uat Performance

    Display ............RS-422 asynchronous serial RS-232 asynchronous serial ARINC 429 traffic interface Altitude Encoder ........... RS-232 asynchronous serial ARINC 429 ADC/AHRS source Control Panel..........RS-232 asynchronous serial External Position Input........From ARINC 743A source GDL 90 Installation Manual 560-1049-02 Rev. B...

  • Page 14: Antenna Requirements

    General Information 1.3.7 Antenna Requirements 1.3.7.1 GPS Antennas The GDL 90 may be installed with the Garmin AT A-33 and A-34 GPS antennas. The following table summarizes the antenna identification. Part Order Model/Description Mount Style Manufacturer Number Number Aero Antenna...
  • Page 15 Group Delay (3dB bandwidth) ....27 ±10 nanosecond Pass Band Ripple (3dB bandwidth) …….0.2 dB max 1.3.7.2 A-34 (590-1112) The Garmin AT A-34 is an acceptable antenna. For specifications of the A-34 antenna, refer to the latest revision of P/N 560-5047-( ). 1.3.7.3 UAT Antenna The GDL 90 requires a UHF antenna meeting the following specifications: Standard 50 vertically polarized antenna with a VSWR <...

  • Page 16: Regulatory Compliance

    The installation of the GDL 90 must also comply with the operational limitations shown in Chapter 3 of this document. 1.4.4 FCC Grant of Equipment Authorization The GDL 90 has been issued an FCC Grant of Equipment Authorization. The FCC ID is marked on the equipment nameplate. 1.4.5 GDL 90 STC Authorization Refer to the GDL 90 Product CD 140-0063-xx for data regarding GDL 90 STC authorization.

  • Page 17: Unpacking The Equipment

    Retain all shipping containers and packaging material in case reshipment is necessary. Package Contents As shipped from the Garmin AT factory, the GDL 90 package includes most necessary items for installation other than supplies normally available at the installation shop, such as wire and cable ties, circuit breakers, and required input and output equipment.

  • Page 18: Definitions & Acronyms

    Cable tie 224-0404 Screw, 4-40 x 1/4 SS flat head Phillips 82 deg. 245-0027 Crimp contact, DSUB, 20 to 24 AWG wire 310-0461-00 Cover Mounting Tray GDL 90 310-0462-00 Mounting Tray GDL 90 430-6200-000 Aircraft Personality Module (APM) 660-0014 Cable, coax RG400 dbl shield 50-ohm (feet) Table 1-6.

  • Page 19: Nstallation

    Complete an electrical load analysis in accordance with AC 43.13-1B, Chapter 11, on the aircraft prior to starting modification to ensure aircraft has the ability to carry the GDL 90 load. Refer to Section 2.10 for the power consumption of each GDL 90 mode of operation. Document the results of the electrical load analysis on FAA Form 337.

  • Page 20: Special Tools Required

    6.4-pound unit. If it is necessary to build a shelf or bracket to mount the GDL 90 tray or it is not certain that the chosen location is of sufficient structural integrity, refer to Appendix D.
  • Page 21 Installation Procedures Install tray in accordance with AC 43.13-2A Chapter 2 Radio Installations. Ensure that the GDL 90 chassis has a ground path to the airframe by having at least one mounting screw in contact with the airframe. For the best resistance to moisture, install the tray in the upright vertical orientation with the optional cover.
  • Page 22 Installation Procedures UAT Mounting Locations Aft of Baggage Under Seat EE Bay Figure 2-2. Multi-Engine Aircraft GDL 90 Mounting Locations 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 23 Installation Procedures Figure 2-3. GDL 90 Mounting Tray and Dimensions GDL 90 Installation Manual 560-1049-02 Rev. B...
  • Page 24 Operating the GDL 90 without RF terminations on the Top or Bottom UAT Antenna ports can result in equipment damage. Always operate the GDL 90 with the Top and Bottom UAT Antenna ports terminated with a VSWR ratio of 3.0:1 or less.

  • Page 25: Unit Insertion

    Position the GDL 90 in the mounting tray and slide the unit fully into the tray. Turn the DZUS fastener on the front bottom of the GDL 90 clockwise ¼ turn to lock in the unit. Do not use the DZUS fastener to draw the unit into the tray.

  • Page 26: Gps Antenna

    2.6.1 GPS Antenna The mounting location and cable connections for the GPS antenna are very important. The GDL 90 GPS antenna must have an unobstructed view of the sky during all normal aircraft maneuvering attitudes. The GPS antenna should be mounted using the following guidelines:...
  • Page 27 Installation Procedures Suggestion: Temporarily locate the GPS antenna with coax connected to the GDL 90 and check the GPS performance as described in the GPS Checkout in the Equipment Operational/Functional Test Section. Once a suitable location has been verified, permanently mount the antenna.

  • Page 28: Uat Antennas

    0.5 meters from any FADEC (Full Authority Digital Engine Control). Follow the manufacturer’s instructions for installing the antennas. The GDL 90 receives UAT signals from two antennas, on the top and bottom of the fuselage. Because UAT signals propagate by line-of-sight, simultaneous shadowing of the antennas should be avoided.

  • Page 29: Electrical Connections

    Installation Procedures Electrical Connections The GDL 90 installation kit includes three D-sub connectors and three coax connectors. The connector layouts are shown in Figure 2-8. The D-sub connectors use the supplied crimp contacts as specified in Table 2-2. Make the crimp connections with the crimp tool specified.

  • Page 30: Interface Connector

    Installation Procedures 2.7.1 Interface Connector Definition Figure 2-8. Rear Connector Layout 2-12 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 31 Installation Procedures 2.7.1.1 Main System Connector (P1) The basic GDL 90 interface is handled via a standard density male 15-pin D-SUB connector located at the rear of the unit. The pinout for the connector is defined in Table 2-4. Table 2-4. Main System Connector Pin-Out (P1)
  • Page 32 ARINC 429 Output Channel 3B 429 OUT 2B ARINC 429 Output Channel 2B 429 OUT 1B ARINC 429 Output Channel 1B VIEW LOOKING AT REAR OF UNIT Figure 2-10. 37-pin Connector – P2 2-14 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 33: Functional Descriptions 2.8.1 Power

    Installation Procedures Functional Descriptions 2.8.1 Power Aircraft power is provided to the GDL 90 on the main system connector. The GDL 90 will accept input power from 10 to 40 VDC. P1-1 Power + P1-9 Power + P1-2 Power Ground...

  • Page 34: Status Leds

    2.8.3 Status LEDs The GDL 90 uses 6 LEDs mounted on the front of its enclosure to communicate system status and conditions of various internal functions. The descriptions of the LEDs, with power applied to the unit, are as follows:...

  • Page 35: Discrete Output

    UAT Fail Out The UAT Fail Out (P2-25) is used to indicate the status of the GDL 90 or status of its internal GPS receiver. The function of this discrete output can be configured via the APM setup (refer to Section 3.0.)

  • Page 36: Discrete Inputs

    Audio Inhibit In The Audio Inhibit In is used to inhibit the GDL 90 audio messages. A ground on this input causes GDL 90 audio messages not to be played; if this input is open GDL 90 audio messages will be played.
  • Page 37 Serial Interfaces 2.8.6.1 RS-232 / RS-422 The GDL 90 provides two bi-directional RS-232 serial interfaces, up to two receive-only RS-232 serial interfaces, and one bi-directional RS-422 serial interface for making optional connections. The serial ports can be used for connecting to:...
  • Page 38 RS-422 Display Interface: The GDL 90 uses Port 3 (RxD3 +/- and TxD3 +/-) to interface to displays such as the MX20 and GMX 200 that use an RS-422 interface. The interface type can be selected for MX20 format, or the Traffic Alert (for the GMX 200) or Pass-through formats found in the Public ICD.
  • Page 39 Installation Procedures 2.8.6.2 ARINC 429 The GDL 90 provides four ARINC 429 inputs and four ARINC 429 outputs. Each of these may be configured for low-speed or high-speed operation with odd parity. P2-15 429 IN 1A /RS232 RxD7 P2-19 429 OUT 1A...

  • Page 40: Suppression Output

    P2-20 Audio Out Lo The GDL 90 provides an audio output for aural traffic advisory messages when the display interface is configured to support Traffic Alerting (Traffic Alert, RS-232, and ARINC 429 interfaces). A discrete input is also provided to allow these audio messages to be inhibited by higher priority systems.
  • Page 41 Include your name and certificate number in the aircraft records. Table 2-6 identifies the weight of the new GDL 90 equipment and Figure 2-9 shows the center of gravity.
  • Page 42 Installation Procedures Figure 2-11. GDL 90 Center of Gravity 2-24 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 43: Electrical Loada

    Installation Procedures 2.10 Electrical Load Analysis The GDL 90 is powered via a separate circuit breaker. For aircraft with multiple power busses, this circuit breaker is sourced from the non-essential bus. An electrical load analysis should be completed on each aircraft prior to installation in accordance with AC 43.13-1B, Chapter 11.
  • Page 44 Installation Procedures Notes 2-26 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 45: Operation

    3 Limitations Operation The installation of a GDL 90 into an aircraft does not alter the operational approvals previously granted to that aircraft. Additional operation approvals may require FAA evaluation of all the systems installed in a particular aircraft and is outside the scope of the GDL 90 STC.

  • Page 46: Flight Manuals

    3.2.3 TCAS Interface The GDL 90’s discrete input TCAS interface is not approved for use. The APM shall not be configured to use the “TCAS installed and interfaced” configuration (Setting ‘2’). If TCAS is installed, use Setting ‘1’. If TCAS is not installed, use Setting ‘0’.

  • Page 47: Traffic Display

    3.2.8 Traffic Display If the GDL 90 is interfaced to a display that uses the GDL 90 Traffic Alert function (such as the GMX 200), the display Pilot’s Guide must contain the following information: Traffic Alerting is only provided for target aircraft that report an integrity value (or containment radius) of less than 1.0 nautical miles Traffic position reports are provided for all targets...
  • Page 48 Limitations Notes 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 49: Mounting And 4.2 Equipment Setup And

    Control" to None, and then click OK. 4. HyperTerminal is now set up to communicate with the GDL 90. Power up the GDL 90, and you should see some lowercase Xs displayed, then several lines of text. After that, when you press the <enter>...
  • Page 50 This command shows the source of the altitude data, and the current altitude value. This command may be used to display the altitude being provided to the GDL 90, as part of a FAR 91.411 24-month check. For a continuous display, use the “alt” command without any parameters. Use “alt once” to display the altitude data once, and use “alt off”...
  • Page 51 GDL 90 installation. The user can quit the initialization procedure at any time (by typing ‘quit’); however the APM changes will not be saved. The new APM settings take effect when the initialization process is completed and the GDL 90 is restarted (by either cycling the power, or typing the “reset” command).
  • Page 52 Post-Installation Configuration and Checkout 4.2.2.7 Discrete Command The Discrete command displays the states of the GDL 90 discrete inputs and outputs. The following table defines the labels used by the “discrete” command. Table 4-2. Discrete Display Format Name Input 1...
  • Page 53 11-29-2005,00:52:03,Yes, 11, 10, 9,SBAS,171, The short GPS status display command is particularly useful when testing for GPS interference. Note: Previous versions of GDL 90 software provided a “GPSstatus” command. This command is no longer supported. GDL 90 Installation Manual 560-1049-02 Rev. B...
  • Page 54 Post-Installation Configuration and Checkout 4.2.2.10 Loader command The “loader” command is used to restart the GDL 90 in data loader mode. This is only used when installing new software or features as instructed in a service bulletin. 4.2.2.11 Playaudio Command The “playaudio”...
  • Page 55 The “service” command causes service information to be returned. It is useful for troubleshooting system failure or malfunction. Example: Service command when no maintenance issues are present. >service No failure detected. See Section 5.2.1 for a complete list of possible service messages. GDL 90 Installation Manual 560-1049-02 Rev. B...

  • Page 56: Micro Apm I

    >version Version Name Number -------------------------------------- Airborne SW 02.10.00 GPS Engine SW 1.20 Micro APM SW 01.00 Radio uCont SW 02.00 FPGA Device RX FPGA Device IO Decode PLD 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 57 4.2.3 Micro APM Initialization Procedure This section describes the procedure for initializing the GDL 90 APM. Each of the APM parameters is described in Table 4-3. The APM initialization procedure is context-sensitive; some of the settings are optional and are omitted as necessary. Some of the APM settings are not used at this time, and are reserved for future use.
  • Page 58 Selection of baud rate for Traffic Alert and Pass-through modes. Serial 422 Uplinks Select from 0, 2, or 4 uplinks per second. Typically, select 2 uplinks per second unless display installation manual instructs otherwise. The MX20 defaults to ‘2’. 4-10 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 59 Height Above 1 = via Serial 422 Terrain (HAT) 2 = via ARINC 429 device (uses ADC or AHRS port) source Indicates how GDL 90 obtains radio altitude or height above terrain information. 4-11 GDL 90 Installation Manual 560-1049-02 Rev. B...
  • Page 60 0 = as UAT Fail Indicator (e.g. lamp) Annunciator 1 = as GPS Valid / UAT Fail indicator (to GSL 71) The GDL 90’s UAT Fail discrete output can be set to function in 2 different ways. Refer to Section 2.8.4.1 for details. Transmit Only...

  • Page 61: Micro Apm C

    • If the MX20 or GMX 200 acts as the GDL 90 controller, verify that the display’s “GDL 90 Code Edit” function is Enabled. However, if the aircraft has both a display and another device used for UAT control (such as a GSL 71 or a Transponder), then the display must be configured to disable the “GDL 90 Code Edit”...
  • Page 62 Post-Installation Configuration and Checkout Notes 4-14 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 65: Equipment Operational

    2. Turn on the GDL 90 and allow the unit to acquire a position. Turn off all other avionics. 3. Verify that the GPS LED on the front of the GDL 90 stops blinking and remains steadily lit within 20 minutes of power-on, indicating unit has acquired a GPS position.
  • Page 66 The remainder of this section provides checkout tips for various types of displays. Typical Display Checkout: If the display is an MX20 and the GDL 90 interface uses the RS-422 port, perform the following checks: With the MX20 in Installer mode, select the FUNC pages and verify that the Message, Traffic, and System functions are enabled.
  • Page 67 Use this procedure to verify that the flight crew’s control selections are reaching the GDL 90. Verify that the Ext LED on the front of the GDL 90 is not illuminated. Enter the “cp” command on the Maintenance port to display the control panel status and data. Operate each control panel input (including the squawk code input if enabled) and verify the correct values are shown on the “cp”...
  • Page 68 Post-Installation Configuration & Checkout Table 4-5. GDL 90 Post-Installation Checkout Log Date: ___/___/___ GDL 90 Post-Installation Checkout Log By: _____________ 430-6081-1_____-______ HW Mod ____ Serial # ___________ SW Mod ____ ARINC 429 Input Configuration: ETUP TEMS Serial Interface Configuration: _____________...

  • Page 69: Troubleshooting

    GDL 90 Maintenance port is essential in troubleshooting. See Section 4.2.1 for setup instructions. In addition, devices connected to the GDL 90, such as a control panel or display can be useful for determining whether the GDL 90 is functioning properly or if there are problems with the installation.

  • Page 70: Collecting Additional

    "MSG 009: APM map version is old." Comment: The GDL 90 software is a newer version than the APM was configured with. The “APMinit” procedure should be used to update the APM map, and correct any undefined settings.

  • Page 71: Messages Fore

    "MSG 020: Invalid magnetic variation file." Comment: The GDL 90 magnetic variation file is invalid or missing. The GDL 90 may continue to be used. Moving map output (if used) will not provide mag var correction. Contact the factory for assistance.

  • Page 72: How To View The Gdl 90 I

    Note: similar procedures apply if the aircraft has a GMX 200. With the aircraft positioned outside and powered-up in view of the sky, start up the GDL 90 and the MX20. After startup, the MX20 ADSB flag should be shown. This indicates that the GDL 90 does not yet have a position fix.
  • Page 73 Efforts made to isolate the problem Technical support via email is available at the following email address: support.salem@garmin.com. Use the following procedure to collect diagnostic information from the GDL 90 Maintenance port. Attach the data file to your email. How to Start a HyperTerminal Text Capture File A HyperTerminal text capture file records the data as it is shown on the screen.
  • Page 74 Now send the file "Capture Nxxxx.txt" from the Desktop folder to the Technical Support email address (support.salem@garmin.com). You will need to either connect the computer to the internet, or move the file from the desktop to a computer with email access.

  • Page 75: Periodic Maintenance

    Audio Alerts If GDL 90 audio alerts are used in the installation, test that the audio level is set correctly. Use the “playaudio” maintenance command, or activate the IDENT function while the aircraft is on ground, if this feature is enabled.
  • Page 76 Periodic Maintenance Notes 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 77: Appendix A - Certification

    Certification Data - Certification Data APPENDIX A A.1 GDL 90 Environmental Qualification - Fixed-Wing For fixed-wing installations, the GDL 90 has been tested to the following environmental categories per procedures defined in RTCA/DO-160D. Environmental Qualification Form Nomenclature: GDL 90 Manufacturer: Part No.:...
  • Page 78 These levels create the DO-160D Figure 8-7 values of 2.97 and 4.20 grms respectively. [2] The GDL 90 passes Category V (Radiated) for all TSO functions except temporary degraded receiver sensitivity at one frequency in the 2 to 3 GHz band.

  • Page 79: Micro Apm E

    Certification Data A.3 Micro APM Environmental Qualification The Micro APM has been tested with the GDL 90 to the following environmental categories per procedures defined in RTCA/DO-160D. Environmental Qualification Form Nomenclature: Micro APM Manufacturer: Part No.: 430-6200-xxx Garmin AT TSO No.:...
  • Page 80 Certification Data Notes 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 81: Appendix B - Troubleshooting

    Serial Interface Specifications - Troubleshooting Flowcharts APPENDIX B GDL 90 Installation Manual 560-1049-02 Rev. B...
  • Page 82 Serial Interface Specifications Notes 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 83 Serial Interface Specifications GDL 90 Installation Manual 560-1049-02 Rev. B...
  • Page 84 Serial Interface Specifications 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 85 Serial Interface Specifications GDL 90 Installation Manual 560-1049-02 Rev. B...
  • Page 86 Serial Interface Specifications Notes 560-1049-02 Rev. B GDL 90 Installation Manual...

  • Page 87: Appendix C - Interconnect

    Interconnect Diagrams - Interconnect Diagrams APPENDIX C GDL 90 Installation Manual 560-1049-02 Rev. B...
  • Page 88 Interconnect Diagrams Notes 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 89 Interconnect Diagrams Figure C-1. Interconnect Diagram for Installation w/ Garmin MFD GDL 90 Installation Manual 560-1049-02 Rev. B...
  • Page 90 Interconnect Diagrams Figure C-2. Interconnect Diagram for Control Panel Installations 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 91 Interconnect Diagrams Figure C-3. Interconnect Diagram for Garmin Displays GDL 90 Installation Manual 560-1049-02 Rev. B...
  • Page 92 Interconnect Diagrams This Page Intentionally Left Blank 560-1049-02 Rev. B GDL 90 Installation Manual...
  • Page 93 Since the combined weight of the GDL 90 and its equipment mounting rack is 6.4 lbs, the static loads which must be applied (Load Factor x 6.4 lbs.) will be the following:...
  • Page 94 Construction and Validation of Structures contact with the fabricated shelf. If it is determined that no damage or permanent deformation has occurred, the structure is of sufficient strength and the GDL 90 equipment rack may be permanently mounted on it.

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