{"id":"F2006B06349","name":"AD/PROP/1 Amdt 2 - Propellers - Overhaul","slug":"ad-prop-1-amdt-2-propellers-overhaul","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47559,"registerId":"commonwealth-F2006B06349-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"VARIABLE PITCH TYPES TBO Hours","sectionType":"part","heading":"VARIABLE PITCH TYPES TBO Hours","content":"# VARIABLE PITCH TYPES TBO Hours\n\n| AEROPRODUCTS         |      |\n| -------------------- | ---- |\n| FN-606 & 606A, A6441 | 2000 |\n\n| AEROMATIC            |     |\n| -------------------- | --- |\n| F200 and F220 Series | 600 |\n\n| AVIA PROPELLERS                                                                                                                           |                                         |\n| ----------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------- |\n| V300 and V400 Series                                                                                                                      | 1000                                    |\n| New Avia V 500A propellers manufactured after 1 January 1994 or overhauled by Avia-Hamilton Standard Aviation (AHSA) after 18 April 1995. |                                         |\n| V 500 AVariant A                                                                                                                          | Normal 2000 Refer Note 11Aerobatic 1400 |\n| V 500 AVariant B                                                                                                                          | Normal 1000 Refer Note 11Aerobatic 700  |\n\n| BEECH AIRCRAFT |     |\n| -------------- | --- |\n| 200 Series     | 900 |\n\n| DE HAVILLAND                        |                                                                                    |\n| ----------------------------------- | ---------------------------------------------------------------------------------- |\n| PD30/211/1 (Proctor)                | 800                                                                                |\n| PD170/212/1 Non-Feathering (DH-114) | 10001400 Subject to mods. 4282 (MNS39)5236 (MNS68) and 1090 (MNS79) beingembodied. |","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This appears to be a technical maintenance schedule excerpt (likely from CASA's Civil Aviation Regulations or an Airworthiness Directive). It has not expanded beyond its original purpose of specifying overhaul intervals for specific propeller models."},"complexity_factors":["Simple tabular format with clear manufacturer/model breakdown","Minimal conditional logic — only basic exceptions (aerobatic vs normal use, specific modification requirements)","No defined terms section or cross-references to other legislation","Short, self-contained document (appears to be an excerpt from a larger maintenance schedule)","Plain language descriptions with minimal technical jargon beyond standard aviation terms (TBO, feathering)"],"plain_english_summary":"This document sets out **maintenance rules for aircraft propellers** — specifically, how many flight hours different types of variable-pitch propellers can operate before they must be overhauled.\n\n**What it does:**\n- Lists specific propeller models from manufacturers like Aeroproducts, Aeromatic, Avia, Beech, and de Havilland\n- Assigns a **Time Between Overhaul (TBO)** to each — the maximum hours allowed before mandatory maintenance\n- Includes special conditions for certain models (e.g., aerobatic use reduces the allowed hours, or specific modifications must be installed)\n\n**Who it affects:**\n- Aircraft owners and operators using these specific propeller types\n- Licensed aircraft maintenance engineers (LAMEs) who perform overhauls\n- Aviation safety regulators ensuring compliance\n\n**Why it matters:**\nPropellers are critical safety components. Operating beyond the TBO without overhaul risks mechanical failure. This document ensures standardized maintenance intervals to keep aircraft safe and airworthy."},"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"},"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":false,"description":"This amendment updates and specifies numerical overhaul intervals and adds conditional qualifications for particular propeller models and variants. It stays within the original, narrowly defined regulatory purpose of prescribing overhaul intervals for variable‑pitch propellers (i.e. it refines technical limits and applicability rather than broadening the instrument into unrelated areas). The change is one of technical calibration (new/adjusted TBO values and conditional pathways) rather than an expansion of regulatory scope."},"complexity_factors":["Multiple propeller models and variants listed with different numeric TBOs","Conditional TBOs (dependence on manufacturing/overhaul dates or organisation)","Different TBOs for normal versus aerobatic use for some variants","Cross‑references to modification numbers (e.g. 4282 (MNS39), 5236 (MNS68), 1090 (MNS79)) without in‑text explanations","References to notes (e.g. \"Refer Note 11\") that are not included in the extract","Formatting inconsistencies and apparent typographical ambiguities (e.g. \"10001400\" run together)","Technical dependencies that require maintenance/engineering verification (embodiment of mods)","Need for accurate provenance and logbook evidence (manufacture/overhaul dates and who performed them)"],"plain_english_summary":"**What this instrument does (mechanically)\n\n- Sets mandatory overhaul intervals (Time Between Overhaul, “TBO”) in flying hours for specific variable‑pitch propeller models.  Each listed propeller model or variant has a numeric TBO (for example, some models are 600 hours, others 2,000 hours).\n- Contains conditional entries: some TBOs depend on how the propeller was manufactured or overhauled (dates and service organisations are used as cut‑offs), whether particular modification kits have been embodied, and whether the propeller is used for normal or aerobatic operation.\n\nWho is affected\n\n- Aircraft owners and operators that have any of the listed variable‑pitch propellers fitted. They must comply with the stated overhaul hours.\n- Maintenance organisations and certificated engineers who plan and certify propeller overhauls and logbooks.\n- Aircraft operators who schedule flight hours, inspections and maintenance downtime because the TBO sets when an overhaul becomes due.\n\nWhy it matters\n\n- Safety and continuing airworthiness: the regulator sets TBOs to limit component wear and reduce failure risk by forcing overhauls at defined intervals.\n- Costs and operational planning: earlier or more frequent overhauls increase direct maintenance costs, aircraft downtime and scheduling complexity for operators.\n- Technical compliance: some entries only grant longer TBOs if specific modification(s) are embodied or if the propeller was manufactured/overhauled by a particular organisation on or after a stated date. That creates a mechanical compliance pathway (either carry out the mods or accept the shorter TBO).\n\nKey operational mechanics and examples\n\n- TBOs are expressed in flight hours by model. Example entries from the instrument include:\n  - \"FN‑606 & 606A, A6441\" — TBO 2,000 hours.\n  - \"F200 and F220 Series (Aeromatic)\" — TBO 600 hours.\n  - \"Avia V300 and V400 Series\" — TBO 1,000 hours.\n  - \"Avia V500A Variant A\" — Normal 2,000 hours; Aerobatic 1,400 hours.\n  - \"Avia V500A Variant B\" — Normal 1,000 hours; Aerobatic 700 hours.\n  - \"Beech 200 Series\" — TBO 900 hours.\n  - \"De Havilland PD170/212/1 Non‑Feathering (DH‑114)\" — 1,000–1,400 hours depending on embodiment of specific mods (listed by reference numbers).\n\n- Where the instrument ties a longer TBO to the embodiment of particular modification(s), the operator has two concrete choices: (a) embody the listed modification(s) and use the longer TBO, or (b) do not embody them and comply with the shorter TBO.\n\nPractical compliance issues to watch for\n\n- Record‑keeping: operators must track manufacturing dates, overhaul history (who overhauled it and when), and whether the listed modifications have actually been embodied to determine which TBO applies.\n- Dual TBOs for different operations: some variants have separate limits for \"normal\" vs \"aerobatic\" operations, so the operator must classify actual usage and may need different maintenance planning depending on how the aircraft is flown.\n- Cross‑references and notes: the instrument refers to modification numbers and notes (for example \"Refer Note 11\" or MNS numbers) that are not reproduced here; those cross‑references need to be checked to apply the entry correctly.\n\nStated purpose vs effects (brief analysis)\n\n- The instrument's stated safety purpose is to maintain airworthiness by limiting propeller service life. That is implemented by imposing deterministic overhaul hours and by allowing longer life only where specific engineering modifications or provenance conditions are satisfied.\n- Who pays: aircraft owners/operators pay the overhaul costs and bear aircraft downtime; maintenance providers perform and certify the work and may capture some business from required overhauls or modification embodiment.\n- Behavioural incentives: operators may (a) elect to embody the listed mods to obtain a longer TBO where permitted, (b) replace propellers with types that have longer TBOs, or (c) adjust operational use to avoid aerobatic categorizations that reduce TBO.\n- Implementation risks and burdens: ambiguity in the table formatting and missing explanatory notes or definitions (for example, how \"Variant A/B\" are determined or the content of referenced notes/MNS numbers) increases the compliance burden and may require direct technical clarification from the regulator or manufacturer.\n\nBottom line\n\n- This instrument prescribes model‑specific overhaul intervals for listed variable‑pitch propellers, with conditional extensions or reductions linked to manufacturing/overhaul provenance, embodiment of specific modifications, and type of operation (normal vs aerobatic). It primarily affects aircraft operators and maintenance providers by changing when overhauls are due and by creating an administrative requirement to prove which TBO applies for a given propeller.**"}},"importantCases":[],"_links":{"self":"/api/acts/ad-prop-1-amdt-2-propellers-overhaul","history":"/api/acts/ad-prop-1-amdt-2-propellers-overhaul/history","analysis":"/api/acts/ad-prop-1-amdt-2-propellers-overhaul/analysis","conflicts":"/api/acts/ad-prop-1-amdt-2-propellers-overhaul/conflicts","importantCases":"/api/acts/ad-prop-1-amdt-2-propellers-overhaul/important-cases","documents":"/api/acts/ad-prop-1-amdt-2-propellers-overhaul/documents"}}