Thales Communications AHV1600 Radio-altimeter Transceiver User Manual

THALES Communications Radio-altimeter Transceiver Users Manual

Contents

Users Manual

THALES Communications ORIGINAL ISSUE : July 16/09 REF : 36719226-AA REVISION No : 0 TP Page 1/2July 16/09 OPERATION AND INSTALLATION MANUAL AHV1600 Radar Altimeter System
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THALES COMMUNICATIONS OIM AHV1600-SYSTEM LIST OF EFFECTIVE PAGES SUBJECT PAGE DATE SUBJECT PAGE DATE LEP Page 1/2July 16/09 Title Page 1 JULY 16/09 2 BLANK Record of Revisions 1 JULY 16/09 2 BLANK Record of Temporary 1 JULY 16/09 Revisions 2 BLANK Service Bulletin List 1 JULY 16/09 2 BLANK List of Effective Pages 1 JULY 16/09 2 BLANK Table of Contents 1 JULY 16/09 2 JULY 16/09 Table of Figures 1 JULY 16/09 2 BLANK Introduction 1 JULY 16/09 2 JULY 16/09 3 JULY 16/09 4 JULY 16/09 Identification sheet 1 JULY 16/09 2 JULY 16/09 General 1 JULY 16/09 2 JULY 16/09 3 JULY 16/09 4 JULY 16/09 Presentation 101 JULY 16/09 102 JULY 16/09 103 JULY 16/09 104 JULY 16/09 105 JULY 16/09 106 JULY 16/09 107 JULY 16/09 108 JULY 16/09 109 JULY 16/09 110 JULY 16/09 111 JULY 16/09 112 JULY 16/09 113 JULY 16/09 114 JULY 16/09 115 JULY 16/09 116 JULY 16/09 117 JULY 16/09 118 JULY 16/09 119 JULY 16/09 120 JULY 16/09 121 JULY 16/09 122 JULY 16/09 123 JULY 16/09 Installation 201 JULY 16/09 202 JULY 16/09 203 JULY 16/09 204 JULY 16/09 205 JULY 16/09 206 JULY 16/09 207 JULY 16/09 208 JULY 16/09 209 JULY 16/09 210 JULY 16/09 211 JULY 16/09 Operation 301 JULY 16/09 302 JULY 16/09
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THALES COMMUNICATIONS OIM AHV1600-SYSTEM TC Page 1/2July 16/09 TABLE OF CONTENTS PAGES INTRODUCTION .................................................................................................................................................11. GENERAL INFORMATION ......................................................................................................................12. BLOCK PAGE NUMBERS FOR SECTIONS ...........................................................................................13. UPDATING ...............................................................................................................................................14. ADVISORIES............................................................................................................................................2A. SAFETY INSTRUCTIONS / ELECTROSTATIC DISCHARGE PRECAUTIONS .................................2B. SHORT - CIRCUIT PRECAUTIONS ....................................................................................................25. UNCOMMON ABBREVIATIONS AND ACRONYMS...............................................................................3GENERAL ...........................................................................................................................................................11. AHV1600 RADAR ALTIMETER MAIN FUNCTION .................................................................................12. AHV1600 BASIC PRINCIPLE ..................................................................................................................13. BUILT IN TEST FUNCTION.....................................................................................................................3A. POWER-UP BUILT IN TEST (PBIT).....................................................................................................3B. INITIATED BUILT IN TEST (IBIT) ........................................................................................................3C. CONTINUOUS BUILT IN TEST (CBIT) ................................................................................................34. AIRCRAFT INTERFACE ..........................................................................................................................3PRESENTATION.............................................................................................................................................1011. AHV1600 RADAR ALTIMETER SYSTEM GENERAL DESCRIPTION ...............................................1012. AHV1600 TRANSCEIVER....................................................................................................................102A. EXTERNAL CHARACTERISTICS....................................................................................................103B. INTERNAL SUB-ASSEMBLIES........................................................................................................106C. FUNCTIONAL CHARACTERISTICS................................................................................................1063. OPERATIONAL INTERFACES ............................................................................................................117A. POWER SUPPLY .............................................................................................................................117B. DIGITAL ARINC429 INTERFACE ....................................................................................................117C. AID SIGNALS INTERFACE..............................................................................................................118D. ENVIRONMENTAL CONDITIONS ...................................................................................................119E. IN FLIGHT CONDITIONS.................................................................................................................1204. ANTENNA ANT-140A...........................................................................................................................120A. GENERALITIES ON ANTENNA ANT-140A .....................................................................................120B. PHYSICAL CHARACTERISTICS .....................................................................................................120C. FUNCTIONAL CHARACTERISTICS................................................................................................1225. COAXIAL CABLES LENGHT ...............................................................................................................122INSTALLATION ...............................................................................................................................................2011. GENERAL CONDITIONS.....................................................................................................................201A. POWER SUPPLY .............................................................................................................................201B. LOCATION........................................................................................................................................201C. WATER, SAND, AND DUST TIGHTNESS.......................................................................................201D. MOUNTING ......................................................................................................................................201E. INSTALLATION CONDITIONS.........................................................................................................2012. STEP BY STEP TRANSCEIVER INSTALLATION...............................................................................202A. CHOICE OF ANTENNAE LOCATION..............................................................................................203B. ANTENNA MOUNTING ....................................................................................................................204C. CONNECTION..................................................................................................................................2053. VERIFICATION ....................................................................................................................................205A. GROUND TESTS .............................................................................................................................205
THALES Communications OIM AHV1600-SYSTEM TC Page 2/2 July 16/09 PAGES B. IN FLIGHT TESTS ........................................................................................................................... 2054. FUNCTIONAL CONNECTIONS WITH RELATED EQUIPMENT........................................................ 205A. INTERFACES CONNECTIONS....................................................................................................... 205B. GROUNDING AND BONDING ........................................................................................................ 206C. COOLING OF THE EQUIPMENT .................................................................................................... 207D. HANDLING....................................................................................................................................... 2075. EQUIPMENT INPUTS / OUTPUTS ..................................................................................................... 207A. MAIN CONNECTOR J1 ................................................................................................................... 207B. RX/TX ANTENNA............................................................................................................................. 210OPERATION................................................................................................................................................... 3011. RADAR ALTIMETER ENERGIZATION ............................................................................................... 3012. FUNCTIONNAL TEST ......................................................................................................................... 3013. NORMAL OPERATING MODE ...........................................................................................................3014. OUT OF RANGE OPERATION ........................................................................................................... 3015. FAILURE MODE .................................................................................................................................. 3016. DEFAULT OPERATING INSTRUCTIONS .......................................................................................... 3027. OPERATIONAL LEVEL MAINTENANCE TASK ................................................................................. 302A. REMOVING THE TRANSCEIVER................................................................................................... 302B. INSTALLING THE SPARE TRANSCEIVER .................................................................................... 302
THALES COMMUNICATIONS OIM AHV1600-SYSTEM TF Page 1/2July 26/09 TABLE OF FIGURES PAGES Figure 1 – AHV1600 TRANSCEIVER SYSTEM ...........................................................................................4 Figure 101 – AHV1600 RADAR ALTIMETER SYSTEM BLOCK DIAGRAM............................................101 Figure 102 – AHV1600 TRANSCEIVER - GENERAL VIEW .............................................................102 Figure 103 – OVERALL DIMENSIONS.....................................................................................................103 Figure 104 – MANUFACTURING SERIAL NUMBER LABEL...................................................................104 Figure 105 – THALES IDENTIFICATION LABEL .....................................................................................104 Figure 106 – AMENDMENT LABEL..........................................................................................................105 Figure 107 – SPECIFIC LABEL ................................................................................................................105 Figure 108 – ORGANIZATION OF HEIGHT DATA WORD LABEL “164” ................................................108 Figure 109 – ORGANIZATION OF STATUS DATA WORD LABEL “271” ...............................................110 Figure 110 – ORGANIZATION OF STATUS DATA WORD LABEL “272" ...............................................112 Figure 111 – ORGANIZATION OF FIRST EQUIPMENT IDENTIFIER DATA WORD LABEL “371” .......112 Figure 112 – ORGANIZATION OF INTERMEDIATE EQUIPMENT IDENTIFIER DATA WORD LABEL “371”....... 113 Figure 113 – ORGANIZATION OF LAST EQUIPMENT IDENTIFIER DATA WORD LABEL “371” .........113 Figure 114 – ORGANIZATION OF STATUS DATA WORD LABEL “377" ...............................................114 Figure 115 – ORGANIZATION OF HEIGHT DATA WORD LABEL “165"................................................116 Figure 116 – ANT-140A INNER SIDE.......................................................................................................121 Figure 117 – ANT-140A OUTER SIDE .....................................................................................................121 Figure 201 – ANT-140A – ANTENNAE SEPARATION AND ORIENTATION..........................................204 Figure 202 – SURFACES BONDING CONTACT OUTLINES ..................................................................206 Figure 203 – INTERCONNECTIONS........................................................................................................211
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THALES COMMUNICATIONS OIM AHV1600-SYSTEM INTRO Page 1July 16/09 INTRODUCTION 1. GENERAL INFORMATION The manual contains the information for the installation and the operation of the AHV1600 Radar Altimeter P/N: AHV1600-01-01 00 A for Aircraft. 2. BLOCK PAGE NUMBERS FOR SECTIONS Each section has a separate block page number:  1 - 99 : General  101 - 199 : Presentation  201 - 299 : Installation  301 - 399 : Operation All values have been given in the units (or multiples or sub-multiples of these units) of the International Sys-tem (S.I.). It is possible that the values are given in more usual units. The English equivalents are given into brackets. 3. UPDATING In case of update of the manual, detailed instructions for the insertion and deletion of applicable pages will be given. Revised texts, new texts or deleted texts will be located with a vertical black line in the margin.
THALES Communications OIM AHV1600-SYSTEM INTRO Page 2 July 16/09 4. ADVISORIES A. SAFETY INSTRUCTIONS / ELECTROSTATIC DISCHARGE PRECAUTIONS This graphic symbol showing a hand on a dark background (to IEC 747-1 standard) means that the equipment on which it appears (assembly or subassembly) contains components sensitive to elec-trostatic discharges. The following rules shall be complied with when carrying out any type of servicing on equipment bearing this symbol:  The equipment shall be placed on a conducting or antistatic-working surface grounded through a resistance of between 250 kohm and 1 Mega-ohm.  The operator shall wear a cotton smock and shall be linked with the working surface by a con-ducting wristband through a resistance of 1 Mega-ohm.  Soldering iron shall be grounded.  The transport and storage of parts removed from the equipment (printed board assemblies, modules, hybrid circuits, etc.) shall be done with conductive or antistatic packaging. B. SHORT - CIRCUIT PRECAUTIONS The inputs/outputs (I/O) are protected from short circuits but, by precautions no servicing shall be performed on any active or passive components while the equipment is energized.
THALES COMMUNICATIONS OIM AHV1600-SYSTEM INTRO Page 3July 16/09 5. UNCOMMON ABBREVIATIONS AND ACRONYMS The following abbreviations, acronyms, and symbols are used in this manual: Abbreviation/Acronym Identification A/D Analogical/Digital AGL Above Ground Level AID Aircraft Installation Delay ANT ANTenna AU Altimeter Unit BIT Built In Test CBIT Continuous Built In Test CR Carriage Return CSCI Computer Software Configuration Item CTZ Coastal Transition Zone CW Continuous Wave D/A Digital/Analogical dB deciBel dBm deciBel milliwatt DC Direct Current DMB Digital and Management Board EMC ElectroMagnetic Compatibility Fb Beat Frequency FM Frequency Modulation FT Functional Test Fore Forward HI HIgh HIRF High Intensity Radiated Fields (Lightning) IBIT Initiated Built-In-Test IEC International Electronical Commission I/O Input /Output LO Low LRU Line Replaceable Unit LSB Lower Significant Bit MAX MAXimum MIN MINimum MPC Multi Purpose Computer NCD No height Computer Data NO Normal Operation PBIT Power On Built In Test PC Printed Card P/N Part Number R/A or RA Radar Altimeter RET RETurn RF Radio Frequency RL Return Loss Rx Reception S.I. International System
THALES Communications OIM AHV1600-SYSTEM INTRO Page 4 July 16/09 Abbreviation/Acronym Identification ST Saw Tooth SWR Standing Wave Ratio Tx Transmission USB Upper Significant Bit VCO Voltage Controlled Oscillator
THALES COMMUNICATIONS OIM AHV1600-SYSTEM IS Page 1July 16/09 EQUIPMENT IDENTIFICATION SHEET F0057 AHV1600_RADAR ALTIMETER SYSTEM PHYSICAL CHARACTERISTICS MAIN COMPONENTS Qty DIMENSIONS (mm) WEIGHT P/N Length Width Height (kg) Transceiver: AHV1600 Antenna: ANT140A Coaxial cables not provided 1 2 190 max 105.41 max 90 max 90.17 max 95 max 33 max  2 kg 0.130 ± 20 g AHV1600-01-01 00 A9599-607-12352 Antenna ANT-140A Coaxial AHV1600 Transceiver
THALES Communications OIM AHV1600-SYSTEM IS Page 2 July 16/09 AHV1600 TRANSCEIVER TECHNICAL CHARACTERISTICS 1- Nominal power supply: 28 Vdc 2- Power consumption: 20 W max (18 W typical) 3- Power input interruption :  2 ms 4- Connection: MIL C 39012 (TNC / RF connectors), MIL C38999 (main connectors) 5- Performance:  Transmission : FM/CW.  Frequency Range : 4.2 GHz to 4.4 GHz.  Frequency Deviation : 123 MHz typical.  Transmitted Power : + 18 dBm max typical.  Height range accuracy : The maximum error, at every simulated height and within the tempera-ture range - 40°C / + 70°C is : (2 ft + 2 % H) 6- Environmental conditions: DO160E Cat. [(B4)X]BBB[RG]XWFDFSZZAZ[ZC][HF]M[(A4G33)(A3J33)]XXAX AHV1600 TRANSCEIVER FUNCTIONAL CHARACTERISTICS – FUNCTIONS OF THE EQUIPMENT: - Provide height Above Ground Level (AGL). – EQUIPMENT INTERFACE: - Transmission antenna. - Reception antenna. - 28 Vdc supply - Main connector
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 1July 16/09 GENERAL 1. AHV1600 RADAR ALTIMETER MAIN FUNCTION The main function of the AHV1600 Radar Altimeter is to provide the height information, via an ARINC 429 digital bus, to the aircraft navigation system, in a range from 0 ft up to 5000 ft. It uses the fact that the electromagnetic waves propagate through the air at a constant speed c, which is the speed of the light. The height information is defined as the shortest distance to the "terrain" (ground or sea). 2. AHV1600 BASIC PRINCIPLE The AHV1600 Transceiver measures altitude above ground as a function of elapsed time from the transmis-sion of the electromagnetic wave to its return after reflection from the ground. The transmission time is di-rectly proportional to the height above ground level. It measures the shortest delay o between the transmitted wave and the received wave, linked to the mini-mum distance to the terrain o by the formula: TERRAIN (GROUND/SEA)ht=2 h/cAIRCRAFT The AHV1600 Transceiver principle of operation is the FM/CW (Frequency Modulation / Continuous Wave) with variable slope modulation. The basic principle of this technique is to generate a saw tooth waveform with a slope of modulation varying as a function of altitude as shown on the figure below. The transmitted wave is linearly modulated in frequency by the saw tooth. cHoo.2
THALES Communications OIM AHV1600-SYSTEM Page 2 July 16/09 The AHV1600 Transceiver performs FM/CW modulation transmissions that are beat against the received reflection. The variable slope modulation allows the beat frequency to be maintained in a given bandwidth (window of 60 kHz to 110 kHz around centre frequency of 80 kHz). The window is then analysed through the equivalent of a 1 kHz bandwidth filter sweeping from 15 kHz to 110 kHz. The evaluation of the aircraft altitude is based on the measurement of the saw tooth duration and the position of the echo frequency in the window. The detection of the beat frequency spectrum is performed by a digital signal processing function. The transmitted wave is linearly modulated in frequency by a saw tooth. A beat signal is then obtained by mixing the transmitted waves F(t) and received waves F(t-i). At every in-stant, the frequency fbi of this signal is equal to: fbi = F(t) - F(t-i) As the modulation is linear fbi is linked to i and then to Hi by the formulae: fbiFiTHicTST ST2.. The fbi frequencies form the beat signal spectrum. This spectrum is constituted of all the frequencies from the ground and the thermal noise as well. To enable a measurement of fbo with a probability of noise detection compatible with the integrity require-ments of the Radio Altimeter, a detection level is de-fined. Only frequencies, which appear in the beat signal with energy above this level are taken into account. As the frequencies fbi and the heights Hi are propor-tional, the minimum distance to the ground Ho is linked to the minimum frequency fbo of the spectrum. The Radio Altimeter then measures this frequency fbo, the leading edge of the spectrum. In the case of the Radio Altimeter, the frequency excursionFis fixed and TST is made proportional to Ho by a feedback loop that keeps fbo in a constant frequency range. The accurate measurement of the minimum fb
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 3July 16/09 in the beat signal spectrum provides an accurate height measurement, and a TST for the feedback loop to keep fbo in its defined frequency range from one measurement to the other. Hence the relationship : Ho K fbo. where FTcKST.2. 3. BUILT IN TEST FUNCTION The AHV1600 Transceiver implements an operational built-in test (BIT) in the following steps: A. POWER-UP BUILT IN TEST (PBIT) The AHV1600 Transceiver is capable of carrying out a performance test upon completion of the ini-tialization sequence after power up to confirm the serviceability of the assembly. This test is per-formed in 3 s. B. INITIATED BUILT IN TEST (IBIT) The AHV1600 Transceiver is capable of carrying out a performance test to confirm the serviceabil-ity of the Transceiver upon receipt of the discrete input signal “FCT_TST“. This test is performed in 3s. C. CONTINUOUS BUILT IN TEST (CBIT) The AHV1600 Transceiver is carrying out a continuous test of performance of the system as a background task. Continuous BIT provides coverage to the minimum extent possible without inter-fering with the normal Transceiver operation. The BIT is controlled by the software embedded by the equipment. 4. AIRCRAFT INTERFACE The AHV1600 transceiver interfaces with the following equipment :  Airborne navigation computer,  Airborne power supply,  Two antennae. The figure 1 shows a block diagram of the AHV1600 radar altimeter system:
THALES Communications OIM AHV1600-SYSTEM Page 4 July 16/09 AVH1600 TRANSCEIVERRadio ModuleDigital/Management Board Mother Board (Including I/O) Power supply ANT140A 4.2 /4.4 GHz Antenna RxReceptionTxEmission RS232 lines Discretes RF signals ARINC 429 lines I/O maintenance Height and status I/O Dedicated informationHIRF Stage ANT140A 4.2 /4.4 GHz Antenna Figure 1 – AHV1600 RADAR ALTIMETER SYSTEM
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 101July 16/09 PRESENTATION 1. AHV1600 RADAR ALTIMETER SYSTEM GENERAL DESCRIPTION The Radar Altimeter System, named AHV1600, consists of three LRU (Line Replaceable Unit) and is com-posed of:  one AHV1600 transceiver,  one antenna ANT-140A to transmit radio frequency (RF) signal,  one antenna ANT-140A to receive radio frequency (RF) signal. Two coaxial cables (not provided) are necessary:  one transmission cable, to connect the transmission antenna to the transceiver,  one reception cable, to connect the reception antenna to the transceiver. Transmission antenna ANT140A LRU Transceiver AHV1600 LRU Reception antenna ANT140A LRU AHV1600_RADAR ALTIMETERReception cable Transmission cable Figure 101 – AHV1600 RADAR ALTIMETER SYSTEM BLOCK DIAGRAM The AHV1600 is an autonomous system mounted on an aircraft and connected to:  28 Vdc power supply line:  “P28V” and “RET28V” signals.  Transmit and receive antennae for Radio Frequency (RF) signals through coaxial cables (“TX and RX” signals).  Navigation and guidance systems through:  Dual differential ARINC429 digital output serial line (“TX429_HI_1, TX429_LO_1 and TX429_HI_2, TX429_LO_2” signals).
THALES Communications OIM AHV1600-SYSTEM Page 102 July 16/09  Two discrete inputs (“FCT_TST and TST_INH” signals).  Configurable inputs (“AID<2..0>, AID_P and SDI_SEL” signals). 2. AHV1600 TRANSCEIVER The AHV1600 Transceiver is a compact and very light system. It is intended to fit the aircraft. It is fixed on the aircraft structure by means of four M6 screws. The unit is made up of a chassis with a front panel. The front panel is equipped with:  one main connector,  two coaxial connectors:  one reception connector« Rx »,  one transmission connector« Tx ». Figure 102 – AHV1600 TRANSCEIVER - GENERAL VIEW Manufacturing serial number label THALES identification label Specific label amendment label ESD (Electro Static Discharge) label Immunity label Transmission connector Reception connector Main connector
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 103July 16/09 A. EXTERNAL CHARACTERISTICS (1) PHYSICAL CHARACTERISTICS Dimensions (see figure 103): max. 190 x 90 x 95 mm. The weight of the unit is < 2 kg. Figure 103 – OVERALL DIMENSIONS Note: all dimensions are in mm (2) FRONT PANEL The front panel bears the antennae connectors, the main connectors , the specific label, the amendment label, the ESD label and the immunity label. All connectors are equipped with special caps provided electrical shielding as well as mechanical protection.
THALES Communications OIM AHV1600-SYSTEM Page 104 July 16/09 (3) IDENTIFICATION (a) Manufacturing Serial Number Label The manufacturing serial number label is stuck on the left side (refer to Figure 102). It is di-vided into four fields, which provide the following indications: Field Number Field 1 Serial number 2 LRU Description 3 Date of manufacturing 4 Inspection stamp (b) THALES Identification Label The THALES identification label is stuck on the left side (refer to Figure 102). One field pro-vides the following indication: Field Number Field 1 THALES commercial part number Figure 104 – MANUFACTURING SERIAL NUMBER LABEL Figure 105 – THALES IDENTIFICATION LABEL 1 2 3 41
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 105July 16/09 (c) Amendment label (d) Specific label The specific label is stuck on the front panel (refer to Figure 102). It is divided into five fields, which provide the following indications: Field Number Field 1 ETSO certification number 2 TSO certification number 3 FCC ID designation 4 DO designation 5 Weight Figure 106 – AMENDMENT LABEL Figure 107 – SPECIFIC LABEL 12345
THALES Communications OIM AHV1600-SYSTEM Page 106 July 16/09 B. INTERNAL SUB-ASSEMBLIES The AHV1600 Transceiver contains the following sub-assemblies: – The Digital chassis:  Performs the High Intensity Radiated Field (HIRF) protection, internal module interconnection, digital and management processor capacity and power supply distribution,  Provides the helicopter with the mechanical and electrical interfaces,  Provides the hardware support of the downloaded software’s. – The radio module:  Performs the Radio Frequency (RF) signal emission, the Radio Frequency (RF) signal reception and the Beat Frequency (BF) signal extraction. C. FUNCTIONAL CHARACTERISTICS (1) OPERATION DATA  Output signals characteristics : ARINC 429 standard  Radar Altimeter height : ARINC word label 164 and 165 (BNR and BCD)  Radar Altimeter Status : ARINC word label 272  Timing between both word labels is described hereafter:  First ARINC 429 output (serial) : IRS1 TX HI (+) / IRS1 TX LO (-)  Second ARINC 429 output (serial) : IRS2 TX HI (+) / IRS2 TX LO (-)  ARINC 429 specification:  Exchange: unidirectional asynchronous  Word format: 32 bits data transfer with LSB transmitted in first  Label format: 8 bits in octal coding from LSB position of the word  Parity format: 1 odd parity bit at MSB position of the word  Inter word gap: 4 bits minimum Note: on each word, the odd parity bit is always computed from the first 31 data bits of the word.  Bit duration : 80 µs  2 µs  Bit form factor : 40 µs  2 µs Note : the bit duration corresponds to a low speed operation at 12.5 kbps.  ARINC signals Transmission speed : 12.5 kbps  Input signals : AID0, AID1, AID2, AID_P  Low level voltage + 3.5 VDC with sink current < 2mA (logic state 1).  High level voltage  +15.3 VDC with sink current < 1 mA (logic state 0).  Maximum level voltage  +32.2 VDC.
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 107July 16/09 when measured to the “M_GND” reference signal.  Frame structure on IRSx TX HI/LO differential output serial line:  six words transmitted in accordance with the following chronological order: 1- Height data word label 164 2- Status data word label 271 3- Status data word label 272 4- Data word label 371 (first equipment identifier data word) 5- Height data word label 377 6- Height data word label 165  Frame rate on IRSx TX HI/LO differential output serial line: 40 ms  1 ms (2) DATA WORD ORGANIZATION (a) height data word label 164 description : Label data field: Bits<8..1> Label value 001 011 10 164OCT Source Destination Identifier (SDI) data field : Bits<10..9> Discrete input “SDI_SEL” 00 Undefined 01 Discrete grounded 10 Discrete open 11 Not used Functional Test Inhibit (FTI) data: Bits<11> Discrete input “TST_INH” 0 Discrete open 1 Discrete grounded
THALES Communications OIM AHV1600-SYSTEM Page 108 July 16/09 Height data field: Bits<29..13>Height value Height range from 0 ft up to + 5500 ft LSB value 0.125 ft Height value coded in 2 complement on 17 bits (Sign bit<29> - LSB bit<13>) Status Matrix data field (BNR numeric data word): Bits<31..30> Validity 00 Failure warning (FW) 01 No Computed Data (NCD) 10 Functional Test (FT) 11 Normal Operation (NO) 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Parity SM Sign Height data value in BNR format coded in two’s complement LSB Spare FTI SDI LSB Label « 164 » MSB 0 0 0 1 0 1 1 1 0 Figure 108 – ORGANIZATION OF HEIGHT DATA WORD LABEL “164” (b) Status data word label 271 description Label data field: Bits<8..1> Label value 100 111 01 271OCT
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 109July 16/09 Source Destination Identifier (SDI) data field : Bits<10..9> Discrete input “SDI_SEL” 00 Undefined 01 Discrete grounded 10 Discrete open 11 Not used Aircraft Installation delay (AID) data field : Bits<14..11> AID_P AID<2..0> AID Value (fte) 0 111 Reserved 1 111 Configurable input value not authorized 0 110 Configurable input value not authorized 1 110 Reserved 0 101 Configurable input value not authorized 1 101 Reserved 0 100 Reserved 1 100 Configurable input value not authorized 0 011 Configurable input value not authorized 1 011 Reserved 0 010 Reserved 1 010 Configurable input value not authorized 0 001 46.625fte 1 001 Configurable input value not authorized 0 000 Reserved 1 000 Undefined Functional Test data: Bits<17> Discrete input “FCT_TST” 0 Discrete grounded 1 Discrete open
THALES Communications OIM AHV1600-SYSTEM Page 110 July 16/09 Test inhibit data: Bits<18> Discrete input “TST_INH” 0 Discrete grounded 1 Discrete open Status Matrix data field (discrete data word): Bits<31..30> Validity 00 Normal Operation (NO) 01 Not used 10 Not used 11 Failure warning (FW) 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Parity SM Spare Spare Spare Spare Spare Reserved Reserved Reserved Reserved Reserved Reserved TST_INH FCT_TST Reserved Reserved AID_P AID2 AID1 AID0 SDI LSB Label « 271 » MSB 0 0 0 0 0 1 0 0 1 1 1 0 1 Figure 109 – ORGANIZATION OF STATUS DATA WORD LABEL “271” (c) Status data word label 272 description Label data field: Bits<8..1> Label value 010 111 01 272OCT Source Destination Identifier (SDI) data field : Bits<10..9> Discrete input “SDI_SEL” 00 Undefined 01 Discrete grounded
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 111July 16/09 10 Discrete open 11 Not used AHV1600 Transceiver function data field : Bits<18..17> AU Transceiver function” 00 Search 01 Track 10 No function 11 Reserved PBIT / IBIT data : Bits<19> PBIT / IBIT 0 BIT in progress 1 BIT not required AHV1600 Transceiver mode data field: Bits<21..20> AU Transceiver mode 00 Reserved 01 Operational 10 Reserved 11 Reserved Failure data field: Bit<29..24> Logic state Tx antenna Rx antenna PSU I/O CPU Radio 0 Failure 1 No failure Radio failure: Problem detected on radio board CPU failure: Problem detected on CPU board I/O failure: Problem detected on I/O board PSU failure: Problem detected on PSU board Rx antenna failure: Impedance on RX antenna fail (50 ohms not detected) Rx antenna failure: Impedance on TX antenna fail (50 ohms not detected)
THALES Communications OIM AHV1600-SYSTEM Page 112 July 16/09 Status Matrix data field (discrete data word): Bits<31..30> Validity 00 Normal Operation (NO) 01 Not used 10 Not used 11 Failure warning (FW) 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Parity SM Tx_ANT failure Rx_ANT failure PSU failure I/O failure CPU failure Radio failure Spare Spare AU Transceiver mode PBIT / IBIT AU Transceiver function Reserved Reserved Reserved Reserved Reserved Spare SDI LSB Label « 272 » MSB 0 0 0 0 1 0 1 1 1 0 1 Figure 110 – ORGANIZATION OF STATUS DATA WORD LABEL “272" (d) Status data word label 371 description Several words label “371” are required to transmit the equipment identifier data. These words label “371” are encapsulated by the “STX” and “EOT” words label “371” to form the global transmission of the equipment identifier data. 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Parity STX Spare MSB Block Word Count LSB LSB Label « 371 » MSB 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 X X X X X X X 1 0 0 1 1 1 1 1 Figure 111 – ORGANIZATION OF FIRST EQUIPMENT IDENTIFIER DATA WORD LABEL “371” “Name” data field defined as per three characters: Name> Discrete input “SDI_SEL”
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 113July 16/09 RA Undefined RA1 Discrete grounded RA2 Discrete open “Part Number” data field defined as per ten characters. e.g. “61778974AC” “Serial Number” data field defined as all characters from Part Number plus five number char-acters. e.g. “61778974AC11111” 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Parity MSB Character = 3 LSB Spare MSB Character = 2 LSB Spare MSB Character = 1 LSB LSB Label « 371 » MSB 1 0 0 1 1 1 1 1 Figure 112 – ORGANIZATION OF INTERMEDIATE EQUIPMENT IDENTIFIER DATA WORD LABEL “371” The last equipment identifier data word label “371” shall indicate the end of transmission of equipment identifier data by transmitting the “EOT” character. 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Parity EOT Spare LSB Label « 371 » MSB 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 1 1 1 1 Figure 113 – ORGANIZATION OF LAST EQUIPMENT IDENTIFIER DATA WORD LABEL “371”
THALES Communications OIM AHV1600-SYSTEM Page 114 July 16/09 (e) Height data word label 377 description Label data field: Bits<8..1> Label value 111 111 11 377OCT Source Destination Identifier (SDI) data field : Bits<10..9> Discrete input “SDI_SEL” 00 Undefined 01 Discrete grounded 10 Discrete open 11 Not used Equipment identification data field: Bits<22..11> Equipement identification 111 111 11 007HEX Status Matrix data field (discrete data word): Bits<31..30> Validity 00 Normal Operation (NO) 01 Not used 10 Not used 11 Failure warning (FW) 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Parity SM No data MSB Equipment Identification Code LSB SDI LSB Label « 377 » MSB 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 Figure 114 – ORGANIZATION OF STATUS DATA WORD LABEL “377"
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 115July 16/09 (f) Height data word label 165 description Label data field: Bits<8..1> Label value 101 011 10 165OCT Source Destination Identifier (SDI) data field : Bits<10..9> Discrete input “SDI_SEL” 00 Undefined 01 Discrete grounded 10 Discrete open 11 Not used Height data field: Bits<29..11>Height value Height range from 0 ft up to + 5500 ft LSB value 0.1 ft Height value in binary coded decimal on 19 bits (MSB bit<29> - LSB bit<11>) Status Matrix data field (BCD numeric data word) : Bits<31..30> Validity” 00 Normal Operation 01 No computer Data (NCD) 10 Functional Test (FT) 11 Not used
THALES Communications OIM AHV1600-SYSTEM Page 116 July 16/09 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Parity SM MSB Height data value in BCD format LSB SDI LSB Label « 165 » MSB 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 0 1 0 1 1 1 0 Figure 115 – ORGANIZATION OF HEIGHT DATA WORD LABEL “165" (3) DISCRETE INPUT SIGNAL (a) Discrete input signal “FCT_TST” The AHV1600 transceiver receives the discrete input signal “FCT_TST” from the navigation and guidance systems to activate its “Built In Test (BIT)” function. The “FCT_TST” discrete input signal shall initiate the following function of the AHV1600 transceiver:  Built In Test function initiated when it is set to low level voltage (discrete grounded).  Built In Test function not initiated when it is set to high level voltage (discrete open). To initiate the internal Built In Test function of the AHV1600 transceiver, the minimum time duration of “FCT_TST” discrete input signal shall be 200ms when measured at 50% level of the electrical changing voltage. In the AHV1600 transceiver, the “FCT_TST” discrete input signal shall be in accordance with the following electrical characteristics:  Low level voltage  + 3.5 VDC with sink current < 2mA (discrete grounded).  High level voltage  +15.3 VDC with sink current < 1 mA.  Maximum level voltage  +32.2 VDC. when measured to the “M_GND” reference signal. In the AHV1600 transceiver, the discrete input signal ”FCT_TST” shall be protected against the indirect effect of lightning. (b) Discrete input signal “TST_INH” The AHV1600 transceiver receives the discrete input signal “TST_INH” from the navigation and guidance systems to inhibit its “Built In Test (BIT)” function. The “TST_INH” discrete input signal shall inhibit the following function of the AHV1600 trans-ceiver:
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 117July 16/09  Initiated Built In Test (IBIT) function inhibited when it is set to low level voltage (dis-crete grounded).  Initiated Built In Test (IBIT) function enabled when it is set to high level voltage (dis-crete open). In the AHV1600 transceiver, the discrete input signal “TST_INH” shall be in accordance with the following electrical characteristics:  Low level voltage  + 3.5 VDC with sink current < 2mA (discrete grounded).  High level voltage  +15.3 VDC with sink current < 1 mA.  Maximum level voltage  +32.2 VDC. when measured to the “M_GND” reference signal. To inhibit the internal Built In Test function of the AHV1600 transceiver, the minimum time du-ration of “TST_INH” discrete input signal shall be 200ms when measured at 50% level of the electrical changing voltage. In the AHV1600 transceiver, the discrete input signal ”TST_INH” shall be protected against the indirect effect of lightning. 3. OPERATIONAL INTERFACES A. POWER SUPPLY The Transceiver shall be powered with a 28 Vdc ± 5 %. The voltage transients shall be:  range 21 V to 32 V for up to 2 ms,  range 21 V to 38 V for up to 1 ms. The Transceiver shall be not damaged in unusual conditions:  50 V during 50 ms. B. DIGITAL ARINC429 INTERFACE This digital interface outputs the altitude information exchanged between the Transceiver and the navigation computer. There is no ARINC 429 input. All information is through the Main receptacle J1. ARINC 429 outputs are differential output signals:  first ARINC429 output (IRS1 TX HI / IRS1 TX LO),  second ARINC 429 output (IRS2 TX HI / IRS2 TX LO).* (1) ELECTRICAL CHARACTERISTICS (a) When measured to the AID ground reference signal in open circuit - differential low level voltage : - 10 Vdc  1 Vdc - differential high level voltage : + 10 Vdc  1 Vdc
THALES Communications OIM AHV1600-SYSTEM Page 118 July 16/09 - differential null level voltage : 0 Vdc  0.5 Vdc - differential output impedance : 75   5  (b) When measured to the AID ground reference signal in loaded circuit - differential low level voltage : between  - 11 Vdc and  - 7.25 Vdc - differential high level voltage : between  + 7.25 Vdc and  + 11 Vdc - differential null level voltage : between  - 0.5 Vdc and  + 0.5 Vdc (2) LIGHTNING PROTECTION Both differential output signals are protected against the indirect effect of lightning. (3) TIMING CHARACTERISTICS - Differential rise time : 10 µs  5 µs. - Differential fall time : 10 µs  5 µs. When measured from 10% to 90% level of the differential changing voltage in open circuit. C. AID SIGNALS INTERFACE (1) CONFIGURABLE INPUT SIGNALS The transceiver receives the configurable input signals “AID_P” and “AID 2..0” from the Naviga-tion computer to code the Aircraft Installation Delay. To select the Aircraft Installation Delay, each dedicated “AID_P” and “AID 2..0” configurable input signal must be connected as short as possi-ble to the “AID GROUND” reference signal (or left open). (2) ELECTRICAL CHARACTERISTICS - Low level voltage :  + 3.5 Vdc with sink current  2 mA (logic state 1), - High-level voltage :  + 15.3 Vdc with sink current  1 mA (logic state 0), - Maximum level voltage  + 32.2 Vdc. When measured to the “M_GND” reference signal. (3) LIGHTNING PROTECTION - Configurable input signals are protected against the indirect effect of lightning. (4) FUNCTIONAL CHARACTERISTICS - AID length definition: from TX transceiver output to TX antenna through coaxial cable and from TX antenna to ground through the air and from ground to RX antenna through the air and from RX antenna to RX input transceiver through coaxial cable - AID is coded by the “AID_P” and “AID 2..0” configurable input signals.
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 119July 16/09 (5) PERFORMANCE  Altitude: 5000 ft  Height accuracy: ( 2 ft + 2% of the true height) D. ENVIRONMENTAL CONDITIONS DO160E Cat. [(B4)X]BBB[RG]XWFDFSZZAZ[ZC][HF]M[(A4G33)(A3J33)]XXAX Environmental Condition DO160E DO160E section Description of conducted test Temperature and altitude 4 Category B4 Temperature variation 5 Category B Humidity 6 Category B Operational shocks and crash safety 7 Category B Vibration 8 Category R curve G Explosive atmosphere 9 Not required Category X Waterproofness 10 Category W Fluids susceptibility 11 Category F Sand and dust 12 Category D Fungus resistance 13 Category F Salt Fog 14 Category S Magnetic effect 15 Category Z Power input 16 Category Z TCF declares that the AHV1600 Transceiver is able to withstand momentary power interruption up to 2ms (Test condition 1 of table 16-3). Voltage spike 17 Category A Audio frequency conducted suscep-tibility – power inputs 18 Category Z Induced signal susceptibility 19 Category ZC Radio frequency susceptibility (radi-ated and conducted) 20 Category H for Conducted Susceptibility Category F for Radiated Susceptibility Emission of radio frequency energy 21 Category M Lightning induced transient suscepti-bility 22 Pin Injection Tests : Equipment tested to Category (A4) for power lines and (A3) for interconnecting lines. Cable Bundle Tests : Equipment tested to Category (G33) for power lines and (J33) for interconnecting lines.Lightning direct effects 23 Not required Category X Icing 24 Not required Category X Electrostatic discharge 25 Category A Fire, Flammability 26 Not required Category X
THALES Communications OIM AHV1600-SYSTEM Page 120 July 16/09 E. IN FLIGHT CONDITIONS In-flight conditions are defined in the following table: Height range domain From 0 ft to 5000 ft ED-30 height range category B Horizontal velocity From 0 ft/s to 500 ft/s up to H = 500 ft From 0 ft/s to 1000 ft/s up to H = 500 ft Height variation velocity From 0 ft/s to 20 ft/s up to H = 50 ft From 0 ft/s to 50 ft/s at 50 ft < H < 500 ft From 0 ft/s to 500 ft/s at 500 ft < H < 800 ft From 0 ft/s to 2000 ft/s above H = 800 ft ED-30 in-flight condition category L/PPitch angle Range of 0 to ± 25°(at - 3 dB) Roll angle Range of 0 to ± 45°(at - 3 dB) ED-30 in-flight condition category L Radar Altimeter in-flight conditions 4. ANTENNA ANT-140A A. GENERALITIES ON ANTENNA ANT-140A The ANT140A antenna is a flat antenna for AHV1600 Radar Altimeter. The complete installation of the Radar Altimeter requires two identical antennae ANT-140A: one for transmission (Tx) and one for reception (Rx). These two antennae must be suitably located and connected by coaxial cables to the transceiver. The antenna is certified by the DO160B certification. B. PHYSICAL CHARACTERISTICS  Dimensions: 105.41 x 90.17 x 33 mm,  Weight: 130 ± 20 g, The antenna is fitted with a female TNC 50 ohms coaxial connector. The connector is protected with a special cap that must be removed before connecting the antenna. Two labels equip the antenna: an identification label and an amendment label. A red ink marking indicates antenna orientation into aircraft.
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 121July 16/09 The outside bears the inscription “DO NOT PAINT”, as well as an antenna-positioning symbol. Figure 117 – ANT-140A OUTER SIDE A: Antenna-positioning symbol Figure 116 – ANT-140A INNER SIDE A Longitudinal Axle
THALES Communications OIM AHV1600-SYSTEM Page 122 July 16/09 C. FUNCTIONAL CHARACTERISTICS – Operating frequency band: 4.2 GHz – 4.4 GHz. – Match:  The return loss on 50 ohms complies with the following diagram  Isotropic gain:  ≥ 7 dBi from 4.2 GHz to 4.4 GHz  Radiation pattern: Half-power beamwidth (- 3 dB):  Roll (E-Plane) : 60°  7°  Pitch (H-Plane) : 50°  5° NOTE: The E-plane is perpendicular to the direction of the straight line painted on the external antenna front face. The H-plane is parallel to the direction of the straight line. – Decoupling:  The decoupling value for a distance of 0.4 m between antenna centres is ≥ 72 dB. – Grounding:  The resistance between connector core and its shielding is < 0.05 ohm. 5. COAXIAL CABLES LENGHT (1) RECOMMENDED CABLE TYPE ( ACCORDING TO MIL.C 17F SPECIFICATION ) Double screened coaxial is essential to avoid RF leakage.
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 123July 16/09 (2) AID DEFINITION Installation Delay (AID) is the total electrical length from the transceiver transmitting output port to the aircraft skin, via the transmitting antenna the add to the distance from the antenna to the ground, add to the distance from ground to receive antenna and back to the transceiver receiving output via the receiving antenna. L1+ L2 Electrical length (in feet) of the coaxial cables between the transceiver and transmitting and receiving antennas respectively. L3 + L4 Distance (in feet) between transmitting and receiving antennas to the ground when the aircraft is on the ground ANT1 and ANT2 are the electrical length (in feet) of antennas (1.5 ft per antenna) The formula for cable mechanical length calculation is: Le +Lr
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 201July 16/09 INSTALLATION 1. GENERAL CONDITIONS A. POWER SUPPLY A nominal voltage of 28 Vdc powers the equipment. It can nevertheless operate within a DC power supply range of 22 V to 30.3 V. The absorbed power at 28 V is less than 20 W. It is typically 18 W. The primary power supply circuit is isolated from the secondary circuit. B. LOCATION When selecting a location for equipment and working out the details for installation in the platform, the objectives should be easy implementation and replacement of the equipment and radar altime-ter as close as possible from the antennae. C. WATER, SAND, AND DUST TIGHTNESS Although the equipment is designed to withstand salt spray and a high degree of humidity, it is not waterproof and precautions should be taken to protect it against trickling or sprayed water (accord-ing to its specifications). D. MOUNTING The AHV1600 Transceiver is fixed on the platform by means of four M6 screws, without any pre-ferred orientation. E. INSTALLATION CONDITIONS The AHV1600 Radar altimeter normal installation conditions are described hereafter:  Radio Frequency (RF) isolation between the transmission and reception antennae > 75 dB.  Adaptation of each antenna 50 ohms, over the frequency range (4.2 GHz to 4.4 GHz).  Gain of each antenna at least 7 dBi and 11 dBi maximum, over the frequency range 4.2 GHz to 4.4 GHz.  Aperture angles of the antennae are at - 3 dB (with ANT-140A):  in pitch ± 25° ± 2.5°.  in roll ± 30° ± 3.5°.
THALES Communications OIM AHV1600-SYSTEM Page 202 July 16/09  VSWR 3 to 1 of each antenna (return loss of - 6 dB or less) over the frequency range 4.2 GHz to 4.4 GHz.  All sides lobes of each antenna must be down 40 dB or better.  Coax cable 50 ohms double shielded type RG400 or equivalent.  Losses in both the transmission and reception coaxial cables are of 4 dB minimum and 7 dB maximum.  Each antenna shall be grounded on the aircraft frame, on a common metallic grounded structure for both antennae. The dimension of this structure being at least 15 cm around each antenna.  No conductive features between antennae or within at least 30 cm around each antenna should be accepted. Furthermore no conductive features should be seen in a cone of ± 70° centered on each antenna.  Avoid antennae to be fitted close to landing gear doors, landing gear or skids.  Antennae should be preferably installed on a flat and horizontal surface. In any cases two an-tennae of a given system shall have no more than a 5° angle between their planes. Furthermore, users have to take into account the fact that tilting any antenna with respect to the aircraft hori-zontal plane will affect the system performances in terms of capability to withstand aircraft’s atti-tudes.  The residual resistance between the structure of the aircraft and the structure of each antenna (body of the coaxial connector) shall not exceed 2.5 milliohm.  The residual resistance between the structure of the aircraft and the structure of the transceiver (body of the coaxial connector, main connector or specific reference mechanical ground pins in the main connector) shall not exceed 2.5 milliohm. 2. STEP BY STEP TRANSCEIVER INSTALLATION The AHV1600 Transceiver is fitted with a main MIL-C-38999 series III, 37 contacts connector and two female MIL-C-39012/TNC coaxial connectors. Two antennae ANT140A – transmission and reception – are required for the AHV1600 Transceiver. They are connected by means of two coaxial cables to the AHV1600 Transceiver. Recommended installation flowcharts:  control the Transceiver visual aspect,  secure the Transceiver,  connect the Main connector,  connect the coaxial cables. Warning: before connecting Main connector, be sure 28 Vdc Transceiver supply is inhibited.
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 203July 16/09 A. CHOICE OF ANTENNAE LOCATION  Choose the location of the antennae carefully. On it will depend the operation of the Trans-ceiver in all flight configurations.  Antennae are generally mounted: Under the fuselage. Such that the H fields are collinear - this configuration corresponds to maximum decoupling between antennae. The antennae centre line should be preferably parallel to the aircraft Fore and AFT axis. Along a plane parallel to the ground for a normal aircraft flight attitude; if it is not possible to mount the antennae horizontally, a maximum angle of 5 degrees may be tolerated. CAUTION: Pitch and roll performances may be degraded for angles exceeding this figure.  At a location that is preferably perfectly clear of any obstacles in order to avoid hindrance of the Transceiver by fixed obstacles (landing gear, fuel tanks, other antennae).  The distance between antennae should be chosen on the basis of two criteria:  Sufficiently large distance to ensure proper decoupling.  Sufficiently small distance to ensure proper overlapping of radiation lobes for the mini-mum height of the antennae above the ground (touchdown or parking position).  The distance between antennae should be the following (see Figure 201).
THALES Communications OIM AHV1600-SYSTEM Page 204 July 16/09 B. ANTENNA MOUNTING Antennae must be flush-mounted, from below, in the lower part of the aircraft fuselage. Antennae connectors must imperatively face:  forwards for the front antenna,  rearwards for the rear antenna. Each antenna bears a red ink marking to indicate assembly orientation into aircraft. Figure 201 – ANT-140A – ANTENNAE SEPARATION AND ORIENTATION
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 205July 16/09 C. CONNECTION The electrical connection for operational use of each antenna is made by means of a single coaxial connector. Type of connector mounted on antenna: 50 ohm female coaxial type TNC connector conforming to specification MIL-C-39012. 3. VERIFICATION When the AHV1600 Transceiver is installed, a verification of the operation must be done using the PBIT. This verification must be done in operational conditions. A. GROUND TESTS - Prior to install the transceiver, check all interfering for continuity and isolation, - Install and connect the transceiver, - Energise the equipment and check that the ARINC output message contains an altitude close to 0ft. Antenna to ground distance may differ in parked situation from the touch down, so this test altitude may vary slightly around 0 ft, - Proceed to Functional Test, the ARINC output message shall contain an altitude of 0 ft exactly, - Check that the coupling to other systems is correct. B. IN FLIGHT TESTS - Sensitivity versus altitude: check that the “loss track” altitude of the radio altimeter is greater than 5000 ft (No Computed Data indication on ARINC output message), - Sensitivity versus attitude: Check that the track is not loss for ROLL and PITCH angles as de-fined by the half power antennae beamwidth. - Immunity from track to landing gear down and the helicopter structure: when flying at an altitude higher than 1000 ft, impose the Functional Test mode. At release of the Functional Test, check that the track mode is recovered and the transceiver outputs a correct altitude different of 0 ft. - 0 ft accuracy: at touch down landing, check that the radio altimeter indicates 0 ft. 4. FUNCTIONAL CONNECTIONS WITH RELATED EQUIPMENT A. INTERFACES CONNECTIONS The following table displays the connector labels, the function, and the connector reference for all connectors used for the AHV1600 transceiver.
THALES Communications OIM AHV1600-SYSTEM Page 206 July 16/09 CONNECTOR LABEL FUNCTION CONNECTOR REFERENCE MATING CONNEC-TOR REFERENCE J1 Main connector MIL C- 38999 / MS27468 T 15 B-35 PN (*) MT934-T15B35P-M112 J2 To Antenna TX MIL C 39012 34MMBX-TNC-50-1/1-2-NE J3 To Antenna RX MIL C 39012 34MMBX-TNC-50-1/1-2-NE (*) Note: The MIL reference designates a connector including the main external characteristics: - 37 pins, - Shell size 15, - Drab olive green finish, - Male contacts, - Normal polarization. B. GROUNDING AND BONDING The bottom part of the chassis is used as mechanical and electrical contact with the aircraft fuse-lage. Figure 202 shows the surfaces providing bonding contact between the Transceiver chassis and the platform structure. Nota : All dimensions are in mm. Figure 202 – SURFACES BONDING CONTACT OUTLINES 16.535. 49213.513.55R 5.7518.9 92 45°
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 207July 16/09 C. COOLING OF THE EQUIPMENT The AHV1600 on platform installation must take into account that heat dissipation for the Trans-ceiver is partially accomplished through natural convection requiring a minimum space between the Transceiver and the next equipment of 10 mm. The remained part of the heat is dissipated by conduction between the bottom part of the Trans-ceiver chassis and the platform frame. The maximum heat dissipation is 20 watts. D. HANDLING No specific tools or support are required to handle or carry the Transceiver due to its small and pre-hensile dimensions and its lightweight. The Transceiver is equipped with caps, which are plugged on each I/O connector, and which pro-tect them from ESD, sand and dust. 5. EQUIPMENT INPUTS / OUTPUTS A. MAIN CONNECTOR J1 Socket Contact Contact Gauge Input (I) / Output (O) Signal Name Wire Type Installation Require-ments 1 22D Reserved 2 22D Reserved 3 22D Reserved 4 22D Reserved 5 22D I FCT_TST Simple see note 4 Discrete input signal 6 22D I TST_INH Simple see note 4 Discrete input signal 7 22D Reserved 8 22D Reserved 9 22D O TX429_HI_1 Twisted/Shielded see note 2&3 Differential output serial line 10 22D O TX429_HI_1 Twisted/Shielded see note 2&3 Differential output serial line 11 22D Reserved
THALES Communications OIM AHV1600-SYSTEM Page 208 July 16/09 Socket Contact Contact Gauge Input (I) / Output (O) Signal Name Wire Type Installation Require-ments 12 22D Reserved 13 22D O TX429_HI_2 Twisted/Shielded see note 2&3 Differential output serial line 14 22D O TX429_HI_2 Twisted/Shielded see note 2&3 Differential output serial line 15 22D Reserved 16 22D I AID2 Simple (as short as possible) see note 4 Configurable input signal17 22D I P28V_1 Twisted see note 1 Power supply input 1 18 22D I P28V_2 Twisted see note 1 Power supply input 2 19 22D I RET28V_2 Twisted see note 1 Power supply return 2 20 22D I AID_P Simple (as short as possible) see note 4 Configurable input signal21 22D Reserved 22 22D Reserved 23 22D I AID 0 Simple (as short as possible) see note 4 Configurable input signal24 22D I AID 1 Simple (as short as possible) see note 4 Configurable input signal25 22D Reserved 26 22D Reserved 27 22D Reserved 28 22D Reserved 29 22D Reserved 30 22D I RET28V_1 Twisted see note 1 Power supply return 1
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 209July 16/09 Socket Contact Contact Gauge Input (I) / Output (O) Signal Name Wire Type Installation Require-ments 31 22D Reserved 32 22D Reserved 33 22D O E_GND Electrical reference ground 34 22D I SDI_SEL Simple (as short as possible) see note 4 Configurable input signal35 22D Reserved 36 22D Reserved 37 22D Reserved Note 1 :Twisted wire type Note 2 : Twisted + Shielded wire type (shield shall be terminated at the connector EMI backshell) Note 3 :ARINC data bus A2 (12.5 Khz)
THALES Communications OIM AHV1600-SYSTEM Page 210 July 16/09 A2 Note 4 : Simple wire type Note 5: The M_GND reference signal must be connected to the mechanical reference ground of the carrier B. RX/TX ANTENNA Connector Contact Contact Gauge Input (I) / Out-put (O) Signal Name Wire Type Installation Requirements RX TNC I RX Coaxial cable TX TNC O TX Coaxial cable Length according to AID selection
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 211July 16/09 Figure 203 – INTERCONNECTIONS AHV1600 TRANSCEIVER INTERNAL DEVICESTX429_HI_1 TX429_LO_2 TX429_LO_1 FCT_TST TST_INH TX429_HI_2 P28V_1 P28V_2 RET28V_2 AID_P AID0 AID1 RET28V_1 E_GND SDI_SEL ARINC 429 LINE ARINC 429 LINES +28Vdc (first) +28Vdc (second) 28Vdc RETURN (second)28Vdc RETURN (first) AID2
THALES COMMUNICATIONS OIM AHV1600-SYSTEM Page 301July 16/09 OPERATION 1. RADAR ALTIMETER ENERGIZATION The AHV1600 radar altimeter is not provided with an “ON-OFF” switch. The equipment starts operating as soon as the + 28 VDC power supply is applied by a circuit breaker or other mean located on the helicopter front panel. 2. FUNCTIONNAL TEST When the functional test is requested, the system shall outputs a 100 ft test height and functional test is indi-cated in the status matrix of word labels 164 and 165. 3. NORMAL OPERATING MODE When on ground or flying in the system range, the radar altimeter shall output the helicopter height above the ground with the specified accuracy. Alarms shall be out of view. The status matrix of ARINC 429 words shall indicate the Normal Operation status. 4. OUT OF RANGE OPERATION When the helicopter is flying outside the system range (above 5000 ft), the radar altimeter shall enters in the loss of track mode (search mode). The status matrix of ARINC 429 words shall indicate the No Computed Data status. 5. FAILURE MODE When a failure is detected by the radar altimeter monitoring, when the helicopter is either on ground or flying, it is signalled. The status matrix of ARINC 429 words shall indicate the Failure Warning status.
THALES Communications OIM AHV1600-SYSTEM Page 302 July 16/09 6. DEFAULT OPERATING INSTRUCTIONS Default Possible cause Corrective action No output data - Radar altimeter not powered - Radar altimeter power supply failure - wiring - Check circuit breaker - Change power supply module - Check wiring Output data with Failure Warn-ing status - Radar altimeter failure - Change transceiver Output data with No Computed Data indication - Loss of system sensitive when heli-copter on ground or flying in the equip-ment operating range - Check antennae installation - Change transceiver 7. OPERATIONAL LEVEL MAINTENANCE TASK The Operational level maintenance task consists in removing and replacing the transceiver (LRU) in case of failure. A. REMOVING THE TRANSCEIVER Recommended removing flowchart: – power-off the transceiver, – disconnect the three cables from front panel, – remove the four M6 screws which secure the unit onto the aircraft structure, – remove the unit. B. INSTALLING THE SPARE TRANSCEIVER Refer to INSTALLATION § 2 Before installing the spare Transceiver, ensure the Transceiver location on aircraft structure is clean.

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