{"id":"F2006B06332","name":"AD/PR/34 Amdt 1 - Hub Through Bolts","slug":"ad-pr-34-amdt-1-hub-through-bolts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47503,"registerId":"commonwealth-F2006B06332-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PR/34 Amdt 1 - Hub Through Bolts","content":"![](image.001.png)\n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/PR/34 and issues the following AD under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and\n\n(c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nPropellers \\- Variable Pitch \\- Dowty Rotol\n\nAD/PR/34\n\nAmdt 1\n\n  \nHub Through Bolts 11/2003\n\nApplicability: All Dowty Rotol propeller 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, and R390/4-123-F/27 installed on SAAB 340A and 340B aircraft excluding those propellers assembled using PR1422-B2 sealant in accordance with Dowty Aerospace Service Bulletin (SB) SF340-61-97.\n\nRequirement: 1. Unless previously accomplished in accordance with Dowty Aerospace Propellers SB SF340-61-96 Revision 1, dated 18 April 2000, inspect the propeller hub through bolts for loss of torque in accordance with Dowty Aerospace Propellers SB SF340-61-96 Revision 2, Accomplishment Instructions, Paragraph 3A(2) though 3A(9).\n\n2. Unless previously accomplished in accordance with Dowty Aerospace Propellers SB SF340-61-96 Revision 1, advise the propeller manufacturer of the results of each inspection and record the results of each inspection in the respective propeller records in accordance with SB SF340-61-96 Revision 2, Accomplishment Instructions, Paragraphs 3B and 3C respectively.\n\nNote: The UK CAA has declared the referenced service bulletin MANDATORY.\n\nCompliance: For Requirement 1: Inspect affected propellers between 500 flying hours and 1800 flying hours from 31 August 2000.\n\nPropellers inspected per the original issue of SB SF340-61-96 must be re-inspected if that inspection was accomplished at a period less than 500 flying hours since the hub was last assembled.\n\nFor Requirement 2: Upon compliance with Requirement 1\\. This Amendment becomes effective on 30 October 2003.\n\nBackground: This Amendment changes the applicability of the propeller to exclude those propellers which have been assembled using PR 1422-B2 sealant that should prevent the hub through torque from reducing. It also clarifies the specific requirements to be complied with within the reference document.\n\nPropellers \\- Variable Pitch \\- Dowty Rotol\n\nAD/PR/34 Amdt 1 (continued)\n\nThis Directive was prompted by reports of cracks in the blade retention area of the hub and extensive fretting damage to the hub mating surfaces. These defects have been attributed to loss of hub through bolt torque. Dowty believes through bolt torque loss is associated with the sealant applied to the hub parting surfaces during assembly.\n\nThis Directive ensures hub through bolt torque is maintained, thereby reducing the potential for cracking and excessive fretting, and provides data for continuing investigation into this problem.\n\nThe original issue of this Airworthiness Directive became effective on 31 August 2000.\n\n![Signature of James Coyne, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nJim Coyne\n\nDelegate of the Civil Aviation Safety Authority 19 September 2003\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 8 October 2003.","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":true,"description":"This amendment narrows the scope compared to the original directive. The original AD/PR/34 applied to all specified Dowty Rotol propellers on SAAB 340 aircraft. Amendment 1 explicitly excludes propellers assembled using PR1422-B2 sealant, based on evidence that this sealant prevents the unsafe condition (torque loss). This represents a refinement based on technical learning rather than expansion."},"complexity_factors":["Multiple cross-references to external service bulletins (SB SF340-61-96 Revisions 1 and 2) without reproducing their content","Nested conditional logic: 'Unless previously accomplished...' exceptions for both requirements","Specific applicability exclusions based on assembly method (PR1422-B2 sealant)","Dual compliance timeframes with a conditional re-inspection trigger","Technical aviation terminology requiring domain knowledge (fretting, hub through bolts, torque loss, blade retention area)"],"plain_english_summary":"This safety order requires operators and maintenance engineers of SAAB 340A/B aircraft with certain Dowty Rotol propellers to inspect hub bolts for loss of torque, record and report results to the manufacturer, and follow corrective actions. Propellers assembled with PR1422‑B2 sealant are exempt. It addresses hub cracking and fretting from loose bolts that can lead to propeller failure; the updated directive took effect 30 October 2003 (inspections due 500–1,800 flight hours after 31 Aug 2000)."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"This Amendment narrows the original AD's applicability by excluding propellers assembled using PR1422‑B2 sealant and clarifies the specific actions and reporting required by referencing Revision 2 of SB SF340‑61‑96. Practically, it reduces the population of affected propellers and adjusts compliance instructions (inspection windows, re‑inspection rule, and mandatory reporting/recording)."},"complexity_factors":["Technical inspection requirement focused on bolt torque and hub fretting (requires mechanical expertise to assess)","Cross‑references to multiple versions of Dowty service bulletin SF340‑61‑96 (Revision 1 and Revision 2) and to SB SF340‑61‑97 for the sealant exception","Exception based on assembly with a specific sealant (PR1422‑B2) which narrows applicability and requires provenance of assembly records","Compliance timing window (500–1800 flying hours) and a re‑inspection trigger for prior inspections done at intervals under 500 hours","Mandatory reporting to the propeller manufacturer and mandatory recording in propeller records (administrative burden on operators)","Legal framing: revocation of prior AD/PR/34 and issuance under CASR subregulation 39.1(1) (regulatory procedure element)","Multiple propeller models listed, increasing scope of parts identification and fleet‑level tracking","Note that the UK CAA declared the referenced service bulletin mandatory (international regulatory cross‑reference)"],"plain_english_summary":"This Amendment requires owners/operators of specified Dowty Rotol propellers on SAAB 340A and 340B aircraft to inspect hub through bolts for loss of torque, and to report and record the inspection results in line with the referenced Dowty service bulletin, unless the propeller was assembled using PR1422‑B2 sealant. The stated purpose is to keep bolt torque and so reduce hub cracking and fretting; the directive shifts inspection, reporting and record‑keeping costs and timing (500–1800 flying hours) onto operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pr-34-amdt-1-hub-through-bolts","history":"/api/acts/ad-pr-34-amdt-1-hub-through-bolts/history","analysis":"/api/acts/ad-pr-34-amdt-1-hub-through-bolts/analysis","conflicts":"/api/acts/ad-pr-34-amdt-1-hub-through-bolts/conflicts","importantCases":"/api/acts/ad-pr-34-amdt-1-hub-through-bolts/important-cases","documents":"/api/acts/ad-pr-34-amdt-1-hub-through-bolts/documents"}}