{"id":"F2008L03355","name":"AD/RAD/51 Amdt 1 - Rockwell International/Collins Aviation Division TDR-94D Transponder","slug":"ad-rad-51-amdt-1-rockwell-international-collins-aviation-division-tdr-94d-transponder","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":120257,"registerId":"commonwealth-F2008L03355-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Radio Communication and Navigation Equip","sectionType":"division","heading":"Radio Communication and Navigation Equipment","content":"### Radio Communication and Navigation Equipment\n\n| AD/RAD/51 Amdt 1 | Rockwell International/Collins AviationDivision TDR-94D Transponder | 10/2008 |\n| ---------------- | ------------------------------------------------------------------- | ------- |\n\n| Applicability: | Rockwell International/Collins Aviation Division TDR-94D Mode S Transponder, part number (P/N) 622-9210-002, installed on, but not limited to, the following aeroplanes:                                                                                                                                                                                                                        |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|                | Beechcraft 300 series.Bombardier (de Havilland) DHC-8 series,Bombardier (Canadair) Challenger CL-601 series,British Aerospace HS 125-700 series,Dassault Mystere-Falcon 200 and 900,Grumman Gulfstream G1159 series,Saab 340A and 340B, andShort Brothers SD3-60.                                                                                                                               |\n| Requirement:   | 1. If not previously accomplished in accordance with the original issue of this Directive or United States Federal Aviation Administration (FAA) AD 93-04-02, fabricate a placard with the following words in letters at least 25mm in height and install the placard within the pilot’s clear view on the instrument panel:                                                                    |\n|                | ‘OPERATION OF TCAS II IN ANY MODE OTHERTHAN THE “TA ONLY” MODE IS PROHIBITED’                                                                                                                                                                                                                                                                                                                   |\n|                | 2. If not previously accomplished in accordance with the original issue of this Directive or FAA AD 93-04-02, modify the software of the transponder in accordance with the Accomplishment Instructions of Collins Service Bulletin TDR-94/94D-34-6 Revision 2 dated 21 September 1992. (The placard mandated by Requirement 1 is no longer necessary after this Modification is incorporated.) |\n|                | Note: FAA AD 93-04-02 Amendment 39-8504 refers.                                                                                                                                                                                                                                                                                                                                                 |\n| Compliance:    | For Requirement 1 - Prior to 25 October 2008.                                                                                                                                                                                                                                                                                                                                                   |\n\n|             | For Requirement 2 - Prior to 1 December 2008.                                                                                                                                                                                                                                                                                                                       |\n| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|             | This Amendment becomes effective on 25 September 2008.                                                                                                                                                                                                                                                                                                              |\n| Background: | Tests have revealed that these Mode S Transponders, when operating in the resolution advisory mode, may loose the capability of co-ordinating with other aircraft. This could result in a near miss situation or mid-air collision. Compliance with this Directive is intended to prevent collisions or near misses caused by failure of these Mode S Transponders. |\n|             | This Amendment results from a request from industry to identify the affected transponder, the amendment adds P/N 622-9210-002 to the applicability statement, updates the list of affected aircraft and corrects minor typographical errors.                                                                                                                        |\n|             | The original issue of this Directive became effective on 27 May 1993.                                                                                                                                                                                                                                                                                               |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n6 August 2008","sortOrder":0},{"sectionNumber":"AD/RAD/51 Amdt 1","sectionType":"part","heading":"AD/RAD/51 Amdt 1","content":"## AD/RAD/51 Amdt 1","sortOrder":1},{"sectionNumber":"Rockwell International/Collins AviationD","sectionType":"part","heading":"Rockwell International/Collins AviationDivision TDR-94D Transponder","content":"## Rockwell International/Collins Aviation  \nDivision TDR-94D Transponder","sortOrder":2},{"sectionNumber":"10/2008","sectionType":"part","heading":"10/2008","content":"## 10/2008","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment remains tightly scoped to its original safety purpose. The changes from the original 1993 directive are minor: adding a specific part number (P/N 622-9210-002), updating the aircraft type list, and fixing typos. The core safety objective — addressing the TCAS coordination failure in these transponders — has not expanded or shifted."},"complexity_factors":["Single, specific technical subject matter (one transponder model)","Only 2 compliance requirements with clear alternative paths","Limited applicability — specific part number and aircraft types listed explicitly","Simple conditional logic ('if not previously accomplished')","Short document with minimal cross-referencing (only references one FAA AD and one service bulletin)","No nested definitions or interpretation sections","Clear deadlines with calendar dates"],"plain_english_summary":"This CASA Airworthiness Directive orders owners/operators of aircraft fitted with the Rockwell Collins TDR‑94D Mode S transponder (P/N 622‑9210‑002) to take urgent action because a software fault can disable TCAS coordination and raise mid‑air collision risk. A temporary cockpit placard restricting TCAS to “TA Only” is required until the mandated software update from the manufacturer is installed; once updated the placard may be removed."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This amendment expands the directive's applicability by adding transponder P/N 622-9210-002 and updates the list of affected aircraft; it also corrects typographical errors. The core safety mandate (placard then software modification) and the original safety purpose remain the same (Background; Applicability; Requirement 1 & 2)."},"complexity_factors":["Narrow applicability tied to a specific transponder part number and enumerated aircraft types (Applicability; Background)","Two-step compliance: temporary operational restriction via placard, plus a technical software modification (Requirement 1 & Requirement 2)","Technical work requires following a specific Collins Service Bulletin (Requirement 2)","Fixed, near-term deadlines for each requirement (Compliance: 25 Oct 2008; 1 Dec 2008)","Placard becomes unnecessary after modification, creating a conditional removal rule (Requirement 2)","Cross-reference to FAA AD 93-04-02 for original mitigation steps (Note)"],"plain_english_summary":"Mandates two fixes for aircraft fitted with Rockwell/Collins TDR-94D Mode S transponder P/N 622-9210-002 and listed types: install a cockpit placard forbidding TCAS II use in modes other than “TA only” (Requirement 1) and install a software modification per Collins Service Bulletin to restore RA coordination (Requirement 2). CASA sets deadlines (placard by 25 Oct 2008; software by 1 Dec 2008). Operators pay for the placard and software work; until modified they must restrict TCAS use, creating a short compliance and maintenance burden."}},"importantCases":[],"_links":{"self":"/api/acts/ad-rad-51-amdt-1-rockwell-international-collins-aviation-division-tdr-94d-transponder","history":"/api/acts/ad-rad-51-amdt-1-rockwell-international-collins-aviation-division-tdr-94d-transponder/history","analysis":"/api/acts/ad-rad-51-amdt-1-rockwell-international-collins-aviation-division-tdr-94d-transponder/analysis","conflicts":"/api/acts/ad-rad-51-amdt-1-rockwell-international-collins-aviation-division-tdr-94d-transponder/conflicts","importantCases":"/api/acts/ad-rad-51-amdt-1-rockwell-international-collins-aviation-division-tdr-94d-transponder/important-cases","documents":"/api/acts/ad-rad-51-amdt-1-rockwell-international-collins-aviation-division-tdr-94d-transponder/documents"}}