Trig Avionics TT31, Modification Instructions

Page 1: ...nt Control Title Generic TT31 Minor Modification Identifier SUP TT31 001 Issue Issue 1 6 Issue Date 21 February 2008 Author Andy Davis Authority Martin Gray CCB Category 2 File Name SUP TT31 001 1 6 Generic TT31 Minor Mod DOC Printed on 28 02 2008 16 05 00 ...

Page 2: ... MODIFICATION 4 3 2 MECHANICAL DETAILS 4 3 3 CONTINUED AIRWORTHINESS INSTRUCTIONS 4 3 4 INSTALLED EQUIPMENT SUITABILITY 5 3 4 1 ETSO 5 3 4 2 Deviations 5 3 4 3 Environmental 5 3 5 WIRING DIAGRAM 6 3 5 1 General Wiring Arrangement 6 3 5 2 Voltage Conversion in 28 Volt Aircraft 7 3 6 ELECTRICAL LOAD ANALYSIS 7 3 7 TESTING DETAILS 7 3 8 FLIGHT MANUAL POH AMENDMENTS 7 3 9 RADIO STATION LICENCE 7 3 10 ...

Page 3: ...A Replacement 10 4 4 8 Install TT31 10 4 4 9 Commission Transponder 10 4 5 POST INSTALLATION TEST 10 4 5 1 Equipment Function 10 4 5 2 Interference Effects 11 4 5 3 Ramp Test 11 5 COMPLIANCE STATEMENT 12 THIS DOCUMENT IS CONFIDENTIAL AND CONTAINS COMMERCIALLY SENSITIVE INFORMATION TO TRIG AVIONICS LTD AND PARTNER COMPANIES THE CONTENTS OF THIS DOCUMENT ARE TO BE KEPT CONFIDENTIAL AND ARE NOT TO BE...

Page 4: ...ear aircraft 1 3 Changes from Previous Issue Section Change Section 1 5 Document Cross References Added Annex I Type Minor Change approval list Section 3 5 Wiring Diagram Corrected error in pin out numbering 1 4 Changes Forecast None 1 5 Document Cross References 1 5 1 Internal Documents 00455 00 TT31 Installation Manual Issue AC SUP TT31 006 Type approved list for TT31 Minor Change approval Issue...

Page 5: ...ue 1 6 ______________________ Trig Avionics Limited Page 2 DC Direct Current DDP Declaration of Design Performance EASA European Aviation Safety Agency ETSO European Technical Standards Order MOPS Minimum Operational Performance Standard POH Pilots Operating Handbook ...

Page 6: ...he light aircraft retrofit market and is designed to be compatible with the existing wiring and installation provisions of current Mode A C transponders In addition to this general compatibility the TT31 is physically directly compatible with the Bendix King KT76A and KT78A Mode A C transponder Replacement of a KT76A or KT78A may therefore be able to reuse some or all of the existing mounting prov...

Page 7: ...e A C transponder and subject to this being correctly sited and in good condition the same antenna will be used The TT31 chassis is mechanically identical to the KT76A and KT78A and fits into the same instrument panel mounting tray The TT31 is slightly lighter by about 100g than earlier models of KT76A but is slightly heavier also by about 100g than later models The difference in weight has no mat...

Page 8: ... Key aspects of the environmental qualification are summarised here DO 160D reference Qualification Applicability Temperature Altitude Category C1 Equipment intended for installation in a non pressurised but controlled temperature location Loss of Cooling 70C without cooling air Forced air cooling not required Temperature Variation Category C Temperature controlled internal section of the aircraft...

Page 9: ...le RF Susceptibility Category T Specified in the HIRF rules representative of the internal EMI environment from aircraft equipment RF Emission Category B Basic emission control In each case the environmental qualification is appropriate to the installation in the instrument panel of a light piston engine aircraft with a DC electrical system 3 5 Wiring Diagram 3 5 1 General Wiring Arrangement The w...

Page 10: ...raw typically 1 1 Amp from the DC power supply with currents of up to 1 9 Amp during high activity The TT31 draws typically 0 25 Amp from a 14V DC power supply on standby with currents of around 0 45 Amp during high activity On 28V supplies the currents are lower Since the current taken by the TT31 is less than half that of the transponder it is replacing any systems that were properly sized to su...

Page 11: ...na cable although could also be an indication of a fault in the existing transponder Transponder transmitted power The existing transponder should provide not less than 125 Watts Class 1 or 70 Watts Class 2 at the antenna Power levels below this may also indicate a problem with the antenna or antenna cable although could also be an indication of a fault in the existing transponder Altitude reporti...

Page 12: ...nnector to determine the method used for voltage conversion The voltage reduction typically uses a resistive dropper attached to the firewall or other metal aircraft structure Remove or bypass the resistive dropper the power supply to the TT31 must come directly from the 28V aircraft supply Consider replacing the transponder mounting tray as discussed in section 3 5 2 4 4 6 KT76A Style Replacement...

Page 13: ...d the TT31 referring to the wiring diagram in section 3 5 Rewire the crimp connector in accordance with the TT31 installation manual 4 4 7 2 Inspect Replace Antenna Connector Inspect the antenna connector removed from the previous transponder tray Although most transponders use compatible blind mate BNC connectors it may be necessary to replace the existing antenna connector if it is damaged or in...

Page 14: ...d 14800 feet are sufficient to ensure proper operation of each altitude code input Verify that the altitude reported is within 125 feet of the supplied altitude NOTE Precautions must be taken during altitude reporting tests to prevent nuisance ACAS Traffic Advisories and ACAS Resolution Advisories to aircraft flying in the area 4 5 3 3 Receiver Sensitivity Verify that for Mode A C interrogations t...

Page 15: ... 23 1301 d Function properly when installed System tested by ground tests on completion Section 4 5 of accomplishment instructions 23 1309 a System must not adversely affect existing systems The system does not interface with any other system except dedicated altitude encoder Installation is physically separate from other systems EMI tests carried out post installation Section 3 5 Wiring Diagram S...

Page 16: ...ight Status COMPLIANT With the exception of Pressure Altitude all these including for the avoidance of doubt the Flight Status requirement are provided directly by the TT31 transponder Pressure Altitude compliance depends on the performance of the altitude encoder 8 1 Mode S Address COMPLIANT Satisfied by assignment from National Authority of Aircraft Registration 8 2 Aircraft 5 700kgs or TAS 250k...

Page 17: ...ry Surveillance ELS COMPLIANT This is a single transponder installation The TT31 transponder is ELS compliant 9 2 Certification standard for transponder is JTSO 2C112a including SI functionality as required by ICAO Annex 10 Amendment 77 COMPLIANT The TT31 is certified to ETSO 2C112b which adopts ED 73B as a Minimum Operational Performance Specification and includes compliance to Annex 10 amendment...

Page 18: ...egistration of the aircraft Testing detailed in Instructions for Continued Airworthiness see 3 3 requires testing which includes 24 bit address and aircraft derived data every 24 months 12 4 Testing of Gillham code data should be based on the transition points as defined in Annex 2 of TGL13 COMPLIANT Encoder testing detailed in Instructions for Continued Airworthiness section 3 3 and section 4 5 3...