{"id":"F2006B11374","name":"AD/MU-2/43 - Autopilot/Electric Trim Switch Standardisation","slug":"ad-mu-2-43-autopilot-electric-trim-switch-standardisation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":57275,"registerId":"commonwealth-F2006B11374-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/MU-2/43 - Autopilot/Electric Trim Switch Standardisation","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nMitsubishi MU-2 Series Aeroplanes\n\nAD/MU-2/43 Autopilot/Electric Trim Switch Standardisation 13/89\n\nApplicability: All models fitted with Bendix model M-4C or M-4D autopilots and/or Bendix electric trim system.\n\nRequirement: 1a. For MU 2B-30 and -35 model aeroplanes manufactured under TC A2PC equipped with a Japanese Civil Airworthiness Board (JCAB) approved Bendix M-4C autopilot; action in accordance with MHI Service Bulletin No 206.\n\n1b. For all other MU 2B model aeroplanes equipped with an FAA approved installation of the Bendix M-4C or M-4D autopilots; action in accordance with MHI SB No 066/22-006.\n\n2. For MU 2B-35 and -36 model aeroplanes with Bendix autopilots installed in accordance with STC SA1693SW and MU 2B-35, -36A, and -60 model aeroplanes with Bendix M-4D autopilots installed in accordance with approved MAI data, fabricate and install a permanent red coloured placard in full view of the pilot using white coloured letters of a minimum of 0.10 inches in height which state:\n\n“COUPLED AUTOPILOT APPROACHES BELOW 125 KIAS OR 300 FEET AGL NOT PERMITTED.”\n\nNote 1: FAA AD 88-13-01 and JCAB AD TCD 2856-87 refer.\n\nNote 2: The serial number of aeroplanes manufactured in the United States by Mitsubishi (MAI) under TC A10SW are suffixed by “SA”. The serial numbers of aeroplanes manufactured in Japan by Mitsubishi Heavy Industries, Inc (MHI) under TC A2PC have no suffix.\n\nCompliance: Prior to 31 March 1990.\n\nBackground: This AD resulted from a request by the National Transportation Safety Board (US) who while investigating a number of fatal MU 2B accidents, concluded that pilots were becoming confused in the operation of the interrupt/disconnect switches for the electric pitch trim and autopilot systems.","sortOrder":0}],"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 Airworthiness Directive remains tightly focused on its original safety purpose: addressing pilot confusion with autopilot/trim switches in Mitsubishi MU-2 aircraft. The scope has not expanded beyond this specific technical safety issue."},"complexity_factors":["Multiple applicability categories requiring different technical actions (1a, 1b, and 2)","Cross-references to foreign regulatory instruments (FAA AD 88-13-01, JCAB AD TCD 2856-87)","Specific technical references to manufacturer service bulletins (MHI SB No 206, MHI SB No 066/22-006)","Precise placard specifications (colour, letter height, wording, placement)","Distinguishing between aircraft manufactured in different countries (US 'SA' suffix vs Japanese no suffix) under different type certificates (TC A10SW vs TC A2PC)"],"plain_english_summary":"This CASA Airworthiness Directive mandates modifications to Bendix autopilot and electric trim switch operations on specified Mitsubishi MU-2 aircraft to eliminate pilot confusion that contributed to fatal US accidents. A permanent cockpit placard bans coupled autopilot approaches below 125 KIAS or 300 ft AGL. Affected MU-2 owners/operators with certain Bendix M‑4 autopilot installations must comply; required work was to be completed by 31 March 1990."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":false,"description":"The AD implements targeted standardisation and a cockpit warning to address pilot confusion identified by the NTSB; it prescribes specific modifications or placarding for defined MU‑2 models and installation types (Requirement 1a/1b/2; Background). The instrument aligns with that stated safety objective and does not broaden obligations beyond measures tied to those approved installations and service bulletins."},"complexity_factors":["Model‑ and installation‑specific applicability (different instructions for MU 2B‑30/-35 under TC A2PC with JCAB approval vs other MU 2B models with FAA approval) — Requirement 1a/1b.","Mandate to follow particular manufacturer service bulletins (MHI SB No 206; MHI SB No 066/22‑006) creates reliance on external technical documents and maintenance actions — Requirement 1a/1b.","Separate requirement to fabricate and install a precisely specified placard (colour, lettering size, exact text) for certain STC/MAI installations — Requirement 2.","Multiple regulatory approvals and installation pathways (JCAB, FAA, STC SA1693SW, MAI approved data) increase variation in compliance steps and recordkeeping — Requirement 1a/1b/2 and Note 2.","Hard compliance deadline (prior to 31 March 1990) concentrates scheduling pressure on operators and maintenance providers — Compliance.","Cross‑references to foreign airworthiness directives (FAA AD 88‑13‑01 and JCAB AD TCD 2856‑87) mean harmonisation with other regulators must be checked — Note 1.","Need to identify aircraft serial‑number suffixes (SA) to determine applicable instructions adds administrative burden — Note 2.","Implementation costs are borne by aircraft owners/operators (modification labour, materials, maintenance downtime); the AD does not specify funding or subsidies — Requirement 1a/1b/2.","Safety rationale is traceable to investigative findings (NTSB) about pilot confusion, which links the mandated actions to behavioural change in cockpit operation — Background."],"plain_english_summary":"Requires owners/operators of Mitsubishi MU‑2 aeroplanes fitted with Bendix M‑4C or M‑4D autopilots or Bendix electric pitch trim to carry out specified modifications or install a permanent cockpit placard, and to follow manufacturer service bulletins. It also bars coupled‑autopilot approaches below a stated speed/height. The rule targets operators, maintenance organisations and manufacturers who must schedule and pay for the work; it was issued in response to NTSB findings about pilot confusion with interrupt/disconnect switches."}},"importantCases":[],"_links":{"self":"/api/acts/ad-mu-2-43-autopilot-electric-trim-switch-standardisation","history":"/api/acts/ad-mu-2-43-autopilot-electric-trim-switch-standardisation/history","analysis":"/api/acts/ad-mu-2-43-autopilot-electric-trim-switch-standardisation/analysis","conflicts":"/api/acts/ad-mu-2-43-autopilot-electric-trim-switch-standardisation/conflicts","importantCases":"/api/acts/ad-mu-2-43-autopilot-electric-trim-switch-standardisation/important-cases","documents":"/api/acts/ad-mu-2-43-autopilot-electric-trim-switch-standardisation/documents"}}