{"id":"F2008L02603","name":"AD/PR/39 - Propeller Blade Outer Sleeve","slug":"ad-pr-39-propeller-blade-outer-sleeve","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":74616,"registerId":"commonwealth-F2008L02603-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Propellers - Variable Pitch - Dowty Roto","sectionType":"division","heading":"Propellers - Variable Pitch - Dowty Rotol","content":"### Propellers - Variable Pitch - Dowty Rotol\n\n| AD/PR/39 | Propeller Blade Outer Sleeve | 8/2008 |\n| -------- | ---------------------------- | ------ |\n\n| Applicability: | Dowty Propellers (part of GE Aviation Systems) Models R354/4-123-F/13,R354/4-123-F/20, R375/4-123-F/21, R389/4-123-F/25, R389/4-123-F/26 andR390/4-123-F/27 propellers.Note 1: These propellers are known to be installed on but may not limited to SAAB SF340A and 340B aircraft.                                                                                                                                                                                                                                          |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. Inspect the blade outer sleeves for cracks in accordance with Dowty Propellers Alert Service Bulletin No. SF340-61-A106 or later NAA approved revision.2. If during any inspection as detailed in Requirement 1 of this AD, a visual indication of a crack on the outer sleeve is found, replace the affected propeller blade with an airworthy unit.Replacement of the blade does not constitute terminating action for the inspection requirements of this AD.Note 2: EASA AD 2008-0033 dated 19 February 2008 refers. |\n| Compliance:    | For Requirement 1: At the next scheduled 1,600 Flight Hours (FH) aircraft check after the effective date of this AD, or after any blade accumulates 15,000 FH time in service, whichever occurs later, and thereafter at intervals not to exceed 1,600 FH.For Requirement 2: Before further flight.                                                                                                                                                                                                                         |\n|                | This Airworthiness Directive becomes effective on 31 July 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                                             |\n| Background:    | A number of propeller blade outer sleeves have been found with cracks since 1996. Testing has shown that blade retention integrity is not affected by this cracking. However, this condition, if not detected and corrected, can lead to blade counterweight release, possibly resulting in damage to the aircraft and injury to occupants or persons on the ground.                                                                                                                                                        |\n\n|     | This AD requires the inspection of the blade outer sleeves and replacement of propeller blades where the outer sleeve is found to have crack indications. |\n| --- | --------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n13 June 2008","sortOrder":0},{"sectionNumber":"AD/PR/39","sectionType":"part","heading":"AD/PR/39","content":"## AD/PR/39","sortOrder":1},{"sectionNumber":"Propeller Blade Outer Sleeve","sectionType":"part","heading":"Propeller Blade Outer Sleeve","content":"## Propeller Blade Outer Sleeve","sortOrder":2},{"sectionNumber":"8/2008","sectionType":"part","heading":"8/2008","content":"## 8/2008","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — addressing a specific cracking issue in specific Dowty propeller models. The scope has not expanded beyond the original safety concern identified in 1996 and confirmed by testing."},"complexity_factors":["Single, specific mechanical component targeted (blade outer sleeve)","Only 2 operational requirements (inspect and replace if cracked)","Straightforward compliance timeline based on flight hours","Minimal cross-referencing (one service bulletin and one EASA AD mentioned)","No nested exceptions or conditional logic — clear 'if-then' structure","Short document (approximately 300 words of substantive content)"],"plain_english_summary":"This AD requires operators of SAAB SF340A/B (and others fitted with the specified Dowty propellers) to inspect the propeller blade outer sleeves for cracks every 1,600 flight hours, beginning at the next check after 31 July 2008 or when a blade reaches 15,000 fh, whichever is later. Any cracked blade must be replaced before further flight, and replacement does not remove the recurring inspection requirement. The rule addresses recurring sleeve cracking that can release counterweights and risk aircraft or ground damage."},"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":3,"scope_assessment":{"changed":false,"description":"The AD enforces recurring inspections and mandatory replacement of cracked blades for the listed Dowty propeller models, consistent with the instrument’s stated safety purpose. It does not expand or narrow the universe of affected parts beyond the models identified, nor does it alter inspection or replacement criteria from those set out in the AD and referenced service bulletin."},"complexity_factors":["Narrow technical scope: applies only to specified Dowty propeller models (listed) rather than all propellers","Operational timing triggers: inspection starts at next scheduled 1,600‑FH check after the AD or once a blade reaches 15,000 FH, then every 1,600 FH","Dependency on a manufacturer Alert Service Bulletin (SF340‑61‑A106) or later NAA‑approved revision for inspection procedures","Replacement before further flight if cracks found (immediate safety action) but replacement does not terminate inspections (ongoing burden)","Cross-reference to EASA AD 2008‑0033 increases regulatory interdependence between authorities","Practical implementation issues: need for inspection labour, parts availability, aircraft downtime and recordkeeping"],"plain_english_summary":"Mechanically, this AD requires operators of specified Dowty variable‑pitch propellers (installed on SAAB 340A/340B) to inspect propeller blade outer sleeves for cracks per Dowty Alert Service Bulletin SF340‑61‑A106 (or later NAA‑approved revision), and to replace any cracked blade before further flight. Inspections begin at the next scheduled 1,600‑FH aircraft check after the AD or once a blade reaches 15,000 FH, then recur every 1,600 FH.\n\nOperators bear inspection and replacement costs and downtime; replacement does not end the inspection requirement. The AD’s stated aim is to prevent blade counterweight release from undetected sleeve cracking."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pr-39-propeller-blade-outer-sleeve","history":"/api/acts/ad-pr-39-propeller-blade-outer-sleeve/history","analysis":"/api/acts/ad-pr-39-propeller-blade-outer-sleeve/analysis","conflicts":"/api/acts/ad-pr-39-propeller-blade-outer-sleeve/conflicts","importantCases":"/api/acts/ad-pr-39-propeller-blade-outer-sleeve/important-cases","documents":"/api/acts/ad-pr-39-propeller-blade-outer-sleeve/documents"}}