{"id":"F2005L01319","name":"AD/PHZL/44 Amdt 9 - Propeller Attachment Bolts","slug":"ad-phzl-44-amdt-9-propeller-attachment-bolts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":35069,"registerId":"commonwealth-F2005L01319-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Propellers - Variable Pitch - Hartzell","sectionType":"division","heading":"Propellers - Variable Pitch - Hartzell","content":"### Propellers - Variable Pitch - Hartzell\n\n| AD/PHZL/44 Amdt 9 | Propeller Attachment Bolts | 7/2005 |\n| ----------------- | -------------------------- | ------ |\n\n| Applicability: | Hartzell Propeller model HC-B3TN-2, HC-B3TN-3, HC-B3TN-5, HC-B4TN- 3,HC-B4TN-5, HC-B4MN-5, and HC-B5MP-3 turbine engine propellers. |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | 1. Install all new propellers and serviceable propellers, as follows:a. Install the propeller oil seal to the engine flange after ensuring that the engine and propeller flanges are clean.b. Carefully install propeller on the engine flange ensuring that complete and true contact is established.c. Apply MIL-T-83483 Petrolated Graphite, or Hartzell Lubricant part number (P/N) A-3338, to threads of the eight P/N B-3339 attaching bolts (and remainder of bolt if desired) and to flat surfaces of the eight P/N A-2048-2 washers, or to other equivalent approved serviceable bolts and washers.d. Install the eight P/N B-3339 attaching bolts and eight P/N A-2048-2 washers, or other equivalent approved serviceable bolts and washers, that were prepared in paragraph 1.c. of this AD, through the engine flange and into the propeller flange.e. Torque all attaching bolts with a torque wrench and an appropriate adapter, to 40 ft.-lbs., and then to 80 ft.-lbs., following sequence \"A\" (shown below). Final torque all attaching bolts using sequence \"B\" (shown below) to 100ft.-lbs. to 105 ft.- lbs. Safety wire all attaching bolts in an approved manner. |\n\n| | f. Once the propeller is installed with P/N B-3339 bolts and P/ N A-2048-2 washers or other equivalent approved serviceable bolts and washers, this AD no longer applies.2. For propellers in the applicability list, that are currently installed with P/NA-2047 attaching bolts:a. check the torque, with a torque wrench and an appropriate adapter, of all eight propeller attaching bolts (with washers installed). Torque should be 100 ft-lbs. to 125 ft.-lbs., with dry threads. Do not use any lubricant with the P/N A-2047 bolts. Safety wire all bolts in an approved manner.Note 1: A P/N A-2047 bolt has the letter \"H\" stamped inside a triangle on the bolt. A P/N B-3339 bolt has the P/N stamped inside the cupped head.b. During torque check per Requirement 2 (a) of this AD, if the torque of any one of the bolts is found to be less than 100 ft.-lbs., remove all eight bolts and washers and replace with P/N B-3339 bolts and P/N A-2048-2 washers, or other equivalent approved serviceable bolts and washers, using procedures described in Requirement 1 of this AD.c. During torque check per Requirement 2 (a) of this AD, if the torque of each P/N A-2047 bolt is in compliance, then at next propeller disassembly, remove all eight bolts and washers and replace with P/N B-3339 bolts and P/N A-2048-2 washers, or other equivalent approved serviceable bolts and washers. Use procedures described in Requirement 1 of this AD.Note 2: Hartzell Service Instructions No. 140A, Revision 9, dated 30 March 2005 is the latest service information that pertains to the subject of this AD.Note 3: FAA Airworthiness Directive (AD) 83-08-01 R2 Amendment 39-14043 refers. |\n| ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Compliance: | 1. Whenever a new or a serviceable propeller is installed on an aircraft after the effective date of this AD.2. a. Within the next 300 hours time-in-service, after the effective date of this AD.b. Before further flight.c. At the next propeller disassembly, after the effective date of this AD. |\n| | This Amendment becomes effective on 7 July 2005. |\n\n| Background: | An improperly secured propeller or failure of propeller attaching bolt can lead to the separation of the propeller from the airplane, resulting in loss of aircraft and / or the occupants.This actions specified in this Airworthiness Directive minimize the safety risks associated with the loss of propeller.Current amendment allows the use of equivalent approved serviceable bolts and washers.Amendment 7 was raised to mandate compliance with Issue 6 of Hartzell SI 140A.Amendment 8 was raised to mandate compliance in accordance with Hartzell Alert SB A203, for those aircraft fitted with Hartzell B5MP propellers.AD/PHZL/44 Amendment 8 became effective in 1994. |\n| ----------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.002.png) \nJames Coyne \nDelegate of the Civil Aviation Safety Authority\n\n19 May 2005","sortOrder":0},{"sectionNumber":"AD/PHZL/44 Amdt 9","sectionType":"part","heading":"AD/PHZL/44 Amdt 9","content":"## AD/PHZL/44 Amdt 9","sortOrder":1},{"sectionNumber":"Propeller Attachment Bolts","sectionType":"part","heading":"Propeller Attachment Bolts","content":"## Propeller Attachment Bolts","sortOrder":2},{"sectionNumber":"7/2005","sectionType":"part","heading":"7/2005","content":"## 7/2005","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"This amendment updates and clarifies technical installation and replacement procedures (including allowing equivalent approved serviceable bolts/washers) but does not materially broaden the AD’s original safety purpose (preventing propeller separation). It tightens/updates compliance detail and permits approved equivalents, rather than expanding the AD’s substantive scope beyond its original airworthiness objective."},"complexity_factors":["Applicability lists 8 specific Hartzell propeller models","Two main requirement tracks (Requirement 1 for new/serviceable installs; Requirement 2 for existing A‑2047 bolts) with multiple subclauses (a–f and a–c)","Conditional logic: torque check thresholds trigger either immediate replacement (<100 ft‑lb) or deferred replacement at next disassembly (>=100 ft‑lb)","Multiple torque steps and prescribed sequences (40 ft‑lb, 80 ft‑lb, then final 100–105 ft‑lb) and specific prohibition on lubrication for A‑2047 bolts","Cross‑references to external technical documents (Hartzell Service Instructions No.140A Revision, FAA AD 83‑08‑01 R2)","Allowance for \"equivalent approved\" parts introduces approval condition and external discretion","Several compliance timing windows (whenever installed; within 300 hours TIS; before further flight; at next disassembly)"],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- Requires specific fastening and replacement procedures for certain Hartzell variable-pitch turbine propellers (models listed under \"Applicability\").\n- For any new or serviceable propeller installed after the AD takes effect, it mandates: install an oil seal; fit the propeller so the engine and propeller flanges make full contact; apply a specified lubricant (MIL‑T‑83483 petrolated graphite or Hartzell P/N A‑3338) to the threads of the specified attaching bolts (P/N B‑3339) and to the flat face of the specified washers (P/N A‑2048‑2) or to other equivalent approved bolts/washers; install eight attaching bolts and washers; torque them in stages (40 ft‑lb, then 80 ft‑lb in sequence “A”, then final torque of 100–105 ft‑lb in sequence “B”); and safety‑wire the bolts in an approved manner. (Requirement 1)\n- For propellers currently fitted with the older P/N A‑2047 bolts, the AD requires a torque check of all eight bolts (dry threads, no lubricant) to 100–125 ft‑lb within the next 300 hours time‑in‑service or before further flight (whichever applies). If any bolt measures below 100 ft‑lb, all eight bolts and washers must be removed and replaced with P/N B‑3339 bolts and P/N A‑2048‑2 washers (or equivalent approved parts) following Requirement 1 procedures. If all A‑2047 bolts comply with torque limits, replacement with B‑3339/A‑2048‑2 is still required at the next propeller disassembly. (Requirement 2a–c)\n- The AD allows use of “equivalent approved serviceable bolts and washers” in place of the Hartzell part numbers, but those equivalents must be approved. (Multiple places)\n- Cross‑references: it relies on Hartzell Service Instructions No.140A (latest revision noted) and refers to an FAA Airworthiness Directive for related background. (Notes)\n\n**Who is affected**\n\n- Aircraft owners and operators who have any of the listed Hartzell propeller models fitted to their aircraft.\n- Maintenance organisations, licensed aircraft maintenance engineers (AMEs), and repair stations that perform propeller installation, torque checks, and disassembly/reassembly work on these propellers.\n- Parts suppliers and manufacturers of the listed bolts and washers (P/N B‑3339, A‑2048‑2 and A‑2047), and any third parties seeking approval for equivalent replacement parts.\n- Regulators and inspectors responsible for enforcing airworthiness directives and approvals for equivalent parts.\n\n**Why it matters (stated purpose and safety mechanism)**\n\n- Stated purpose: prevent propeller separation caused by improperly secured or defective propeller attaching bolts. Propeller separation can lead to catastrophic loss of the aircraft and occupants. The AD prescribes specific installation, lubrication, torque and safety‑wiring procedures to reduce that risk. (Background; Requirements 1–2)\n\n**Costs, incentives and trade‑offs**\n\n- Direct costs to operators: purchase of specified bolts/washers (or approved equivalents), lubricant if not already stocked, labour time to perform torque checks and replacements, and possible aircraft downtime (grounding) if bolts fail the torque check. (Requirements 1–2; Compliance)\n- Incentive structure: replacing A‑2047 bolts with the B‑3339/A‑2048‑2 combination (or approved equivalents) eliminates the need for repeated torque checks under this AD (Requirement 1.f). Therefore operators who adopt the specified replacement quickly remove the AD’s ongoing compliance burden for that aircraft.\n- Competition and supply effects: the AD names Hartzell part numbers, which concentrates near‑term demand on Hartzell parts suppliers. However, the AD explicitly allows “equivalent approved serviceable bolts and washers,” which permits alternatives if they obtain approval — this lowers the risk of vendor lock‑in but creates an approval hurdle (administrative cost/time). (Requirements 1, 2; Notes)\n- Operational risk trade‑off: the AD permits operators to delay full replacement of A‑2047 bolts until the next disassembly if torque checks pass now, which reduces short‑term cost and downtime but leaves the older bolts in service longer and may shift the risk window until disassembly. (Requirement 2.c; Compliance)\n- Implementation risk: correct torque application requires appropriate torque wrenches and adapters and following the prescribed sequences (A then B). Human error in torque procedure, use of lubricant where prohibited (A‑2047 bolts must be dry), or improper safety‑wiring could undermine the intended safety gain. (Requirements 1.e; 2.a; Notes)\n\n**Compliance timing and administrative burden**\n\n- Different compliance triggers apply: immediate for new/serviceable propeller installations; within 300 hours TIS or before further flight for torque checks of existing A‑2047 bolts; and at the next propeller disassembly if torque checks pass. These staggered deadlines create a mix of immediate and deferred obligations that maintenance planners must track. (Compliance and Requirements 1–2)\n\n**Concentrated benefits and diffuse costs**\n\n- Concentrated benefits: manufacturers and suppliers of the specified replacement bolts and washers (or approved equivalents) get additional sales; maintenance organisations obtain work performing checks and replacements.\n- Diffuse costs: aircraft owners/operators (often numerous and geographically dispersed) incur incremental parts and labour costs and potential downtime.\n\n**Practical effect on private decision‑making**\n\n- Owners face a choice: (a) replace A‑2047 bolts promptly with the specified part numbers or approved equivalents to end the AD’s repeated requirements for that aircraft, or (b) conduct the torque check now and defer replacement until next disassembly if the bolts meet torque limits, accepting the residual risk and monitoring burden.\n- Maintenance providers must ensure they have the correct parts, lubricant, torque tools/adapters, and a process to apply the specified torque sequences and safety‑wire method.\n\n**Where discretion or ambiguity remains**\n\n- “Equivalent approved serviceable bolts and washers” requires an approval process (the AD does not specify the approver or standards in‑text), leaving regulatory or manufacturer discretion over acceptable substitutes.\n- Safety‑wire must be done “in an approved manner” — this phrase requires reliance on existing standards or regulator guidance rather than prescribing a single technique in the AD.\n\n**Source‑claimed purpose vs. practical costs**\n\n- The AD’s mechanism (specified parts, lubricant, staged torquing, and safety‑wiring) is targeted at the mechanical causes of bolt loosening or failure and therefore maps directly to its stated safety goal (preventing propeller separation).\n- The practical costs are concentrated on affected operators and maintenance providers; the AD reduces the chance of repeated inspections only after operators adopt the designated replacement parts or approved equivalents.\n\n(Sections cited: Applicability; Requirement 1 and subparts; Requirement 2 and subparts; Notes; Compliance.)"},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":true,"description":"The original AD (implied by Amendment 8 in 1994) mandated specific Hartzell part numbers only. Amendment 9 expands the scope by allowing 'other equivalent approved serviceable bolts and washers' — broadening from a single manufacturer part mandate to a performance-based standard. The background notes this explicitly: 'Current amendment allows the use of equivalent approved serviceable bolts and washers.' This represents a shift from prescriptive to slightly more flexible regulatory approach while maintaining safety standards."},"complexity_factors":["Multiple compliance pathways depending on current bolt type installed (new installation vs. existing A-2047 bolts)","Nested conditional requirements: different actions based on torque check results (below 100 ft-lbs vs. compliant)","Specific part number references (P/N B-3339, A-2048-2, A-2047) with visual identification requirements (stamped markings)","Precise technical specifications: torque values in three stages (40, 80, 100-105 ft-lbs), specific lubricant types (MIL-T-83483 or Hartzell A-3338), and safety wiring requirements","Cross-reference to external technical documents (Hartzell Service Instructions No. 140A Rev 9, FAA AD 83-08-01 R2)","Multiple compliance timeframes: 'effective date', 'within 300 hours time-in-service', 'before further flight', 'at next propeller disassembly'"],"plain_english_summary":"This AD requires operators and maintainers of certain Hartzell turbine propellers to inspect and replace vulnerable propeller attachment bolts (old A-2047 bolts) and follow mandated installation procedures or bolt replacement to ensure secure attachment. It targets aircraft using listed Hartzell models and, by Amendment 9, permits equivalent approved parts.\n\nThis action prevents catastrophic propeller detachment by mandating timely inspections, proper installation, and replacement where bolts are deficient."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-phzl-44-amdt-9-propeller-attachment-bolts","history":"/api/acts/ad-phzl-44-amdt-9-propeller-attachment-bolts/history","analysis":"/api/acts/ad-phzl-44-amdt-9-propeller-attachment-bolts/analysis","conflicts":"/api/acts/ad-phzl-44-amdt-9-propeller-attachment-bolts/conflicts","importantCases":"/api/acts/ad-phzl-44-amdt-9-propeller-attachment-bolts/important-cases","documents":"/api/acts/ad-phzl-44-amdt-9-propeller-attachment-bolts/documents"}}