{"id":"F2006B06259","name":"AD/PL 12/13 - Nose Wheel Pivot Assembly - Inspection","slug":"ad-pl-12-13-nose-wheel-pivot-assembly-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47250,"registerId":"commonwealth-F2006B06259-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PL 12/13 - Nose Wheel Pivot Assembly - Inspection","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)  \nTransavia PL 12 Series Aeroplanes\n\nAD/PL 12/13 Nose Wheel Pivot Assembly \\- Inspection 9/73\n\nApplicability: All models.\n\nRequirement: 1. Remove nose wheel pivot pin P/N 6-24 and detach nose wheel leg pivot assembly P/N 6-202.\n\n    2. Remove nose wheel pivot bushes P/N 6-22. Check that the diameter of the internal bore of the bushes is within 0.501\" and 0.503\" and the diameter of the pivot pin P/N 6-24 is within 0.498\" to 0.500\".\n\n    3. Check parallelism of the facing surfaces of the nose wheel pivot support assemblies. The inner surfaces of the upper and lower support assemblies shall be parallel to within 0.005\" over with width of the faces.\n\n    4. Assemble the spacer P/N 6-23 and bushes onto the pivot pin and measure the distance between the inside of the flanges of the two bushes. Check that the distance between the bearing caps on the nose wheel pivot leg assembly provides a clearance fit between the flanges of the bushes.\n\n    5. Assemble the spacer and bushes in the nose wheel pivot leg assembly, and with the bushes clamped to the spacer, the dimension over the outside of the bushes shall provide a snug push fit between the pivot support assemblies.\n\n    6. When the nose wheel is assembled and the pivot pin torqued in accordance with the manufacturers maintenance manual, the nose wheel shall pivot freely. The end play of the nose wheel pivot leg assembly on the pivot bushes shall be a minimum of 0.008\" and not more than 0.040\".\n\nNote: Only paras. 3 and 6 of requirement document applicable to aircraft incorporating SB No. 27 (incorporated in production from Serial No. G576).\n\nCompliance: Within 100 hours time in service after 12 September 1973 and thereafter at intervals not exceeding 300 hours time in service, and at any time the nose wheel pivot leg assembly is removed.","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":4,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive focused specifically on nose wheel pivot assembly inspection. It has not expanded beyond its original safety purpose. The scope remains tightly confined to the specific mechanical defect it was issued to address."},"complexity_factors":["Six numbered procedural steps with specific part numbers (P/N) and precise dimensional tolerances (e.g., 0.501\"-0.503\", 0.005\" parallelism)","Technical terminology requiring aviation maintenance knowledge (e.g., 'end play', 'torqued', 'clearance fit', 'snug push fit')","Conditional applicability: partial exemption for aircraft with SB No. 27 incorporated (serial numbers from G576 onwards)","Multiple compliance triggers: initial deadline, recurring interval (300 hours), and event-based trigger (removal of assembly)","Cross-reference to manufacturer's maintenance manual for torque specifications","Mixed measurement systems (imperial inches) with precise decimal tolerances requiring specialized measuring equipment"],"plain_english_summary":"This mandatory CASA airworthiness directive requires Transavia PL 12 owners/operators and licensed maintenance engineers to perform a detailed inspection and maintenance of the nose wheel pivot assembly to verify fit, clearances and free movement. It addresses potential wear or assembly defects that could cause nose‑wheel seizure or loss of directional control.\n\nInspections: first within 100 flight hours after 12 Sep 1973 and every 300 flight hours thereafter (and whenever the pivot leg is removed)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD is narrowly targeted at inspecting and verifying dimensional conformity of the nose wheel pivot assembly. It does not add unrelated obligations or expand to other systems. The single exception for aircraft built with Service Bulletin No. 27 (from Serial No. G576) reduces the number of checks for those aircraft rather than expanding scope. Overall, the instrument remains within the original safety-focused purpose of mandating periodic inspection and measurement of specific nose gear parts."},"complexity_factors":["Short, single-aircraft-type directive covering one assembly","Six sequential technical steps with numeric tolerances (no nested legal exceptions)","One limited applicability exception (Service Bulletin No. 27 from Serial No. G576 — affects only paras. 3 and 6)","Cross-reference to manufacturer’s maintenance manual for torque procedure","Technical measurement requirements (multiple tight tolerances: 0.498\"–0.500\", 0.501\"–0.503\", 0.005\", 0.008\"–0.040\")","Event-driven compliance trigger in addition to time intervals (inspection whenever pivot leg assembly is removed)"],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- It requires a physical inspection and dimensional check of the nose wheel pivot assembly on all Transavia PL 12 / PL 13 series aeroplanes.\n- The required work is set out in six steps (Requirement paras. 1–6):\n  - Remove the pivot pin (P/N 6-24) and detach the nose wheel leg pivot assembly (P/N 6-202) (para.1).\n  - Remove the pivot bushes (P/N 6-22) and check the internal bore diameter of the bushes must be between 0.501\" and 0.503\"; the pivot pin diameter must be between 0.498\" and 0.500\" (para.2).\n  - Check that the facing inner surfaces of the upper and lower pivot support assemblies are parallel to within 0.005\" across the face width (para.3).\n  - Fit spacer (P/N 6-23) and bushes to the pin and measure the distance between the insides of the bush flanges; confirm the distance between the bearing caps gives a clearance fit with the bush flanges (para.4).\n  - With spacer and bushes in the pivot leg assembly and bushes clamped to the spacer, confirm the assembled outside-bush dimension gives a snug push fit between the pivot support assemblies (para.5).\n  - After final assembly and torquing per the manufacturer’s maintenance manual, confirm the nose wheel pivots freely and that end-play of the pivot leg on the bushes is at least 0.008\" and not more than 0.040\" (para.6).\n\n- A specific note: aircraft that incorporate Service Bulletin No. 27 in production from Serial No. G576 only need to follow paras. 3 and 6 of the requirements (the parallelism and end-play checks).\n\n- Compliance timing: carry out the inspection within 100 hours time-in-service after 12 September 1973, then repeat at intervals not exceeding 300 hours time-in-service. The inspection must also be done any time the nose wheel pivot leg assembly is removed.\n\n**Who this affects**\n\n- Owners and operators of Transavia PL 12 / PL 13 series aeroplanes (all models).\n- Maintenance organisations and certificated mechanics who perform nose gear maintenance on those aircraft.\n\n**Why it matters (stated purpose and operational effect)**\n\n- The directive’s stated purpose is to ensure the nose wheel pivot assembly components remain within dimensional tolerances and allow correct pivoting and end-play. Mechanically, that reduces the risk of excessive wear, binding, or unexpected movement in the nose gear joint.\n\n**Who pays, who decides, and what behaviour changes**\n\n- Aircraft owners/operators pay for the inspections, measuring equipment, labour and any bush/pin/spacer replacement or repair required.\n- Maintenance organisations and the operator decide when to schedule the inspections within the mandated intervals and whether to repair or replace parts that are out of tolerance.\n- Behaviour changes: operators must add the inspection to scheduled maintenance, may shorten intervals to mitigate risk, and may choose to pre-emptively replace parts rather than repeatedly measure worn components.\n\n**Costs, incentives and trade-offs**\n\n- Direct costs: labour time (engineered disassembly/reassembly), parts if bushings/pin/spacer are out of tolerance, and aircraft downtime while work is done.\n- Incentives: because inspection is required on removal of the pivot leg assembly, operators may avoid unnecessary removals to reduce inspection load; conversely, discovery of wear may push replacement and increase parts demand.\n- Opportunity cost: time and hangar resources spent on these inspections cannot be used for other maintenance.\n- Implementation risks and compliance burden: accurate dimensional measurement requires calibrated gauges and competent technicians; incorrect measurement or improper torquing (required by the manufacturer’s manual) can produce false pass/fail results.\n\n**Effects on private enterprise and market choices**\n\n- Small operators bear the same per-aircraft inspection and repair cost as larger operators; economies of scale in maintenance may encourage use of third‑party MROs (maintenance repair organisations).\n- The directive specifies part numbers and dimensions; this focuses repair demand on parts compatible with those specifications and on suppliers who stock them.\n\n**Practical notes about discretion and exceptions**\n\n- The AD prescribes measurements and limits; there is little administrative discretion in the text — compliance is a matter of meeting the numerically-stated checks.\n- The only built-in variation is the production-SB exception (SB No. 27 from Serial No. G576), which narrows required checks to paras. 3 and 6 for those aircraft.\n\n(Sources: Requirement paras. 1–6 and the Compliance paragraph of the AD.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-pl-12-13-nose-wheel-pivot-assembly-inspection","history":"/api/acts/ad-pl-12-13-nose-wheel-pivot-assembly-inspection/history","analysis":"/api/acts/ad-pl-12-13-nose-wheel-pivot-assembly-inspection/analysis","conflicts":"/api/acts/ad-pl-12-13-nose-wheel-pivot-assembly-inspection/conflicts","importantCases":"/api/acts/ad-pl-12-13-nose-wheel-pivot-assembly-inspection/important-cases","documents":"/api/acts/ad-pl-12-13-nose-wheel-pivot-assembly-inspection/documents"}}