{"id":"F2009L00142","name":"AD/PA-31/118 Amdt 2 - Aileron Spar","slug":"ad-pa-31-118-amdt-2-aileron-spar","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":76577,"registerId":"commonwealth-F2009L00142-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Piper PA-31 Series Aeroplanes","sectionType":"division","heading":"Piper PA-31 Series Aeroplanes","content":"### Piper PA-31 Series Aeroplanes\n\n| AD/PA-31/118 Amdt 2 | Aileron Spar | 2/2009 |\n| ------------------- | ------------ | ------ |\n\n| Applicability: | All PA-31 Series.                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1 (a) Remove the LH and RH ailerons from the aircraft, and remove the inboard and outboard hinge brackets and the control horn brackets. Strip and clean the areas around the bracket attachments including the spar flanges, and inspect the visible surfaces of the front spar element (doubler) for cracks, using an approved dye penetrant inspection procedure. Particular attention should be paid to the hinge bracket attachment and the horn bracket attachment areas; or, |\n|                | (b) Inspect the aileron in accordance with an alternative scheme approved by the Authority.                                                                                                                                                                                                                                                                                                                                                                                         |\n|                | 2 (a) If any cracking or damage is identified, dismantle sufficient of the aileron structure to remove the spar doubler and gain good access to the main spar element, and the aft rib forward flange, in the vicinity of the identified defect. Inspect all surfaces in the area using an approved dye penetrant inspection procedure.                                                                                                                                             |\n|                | (b) Repair cracking and damage in accordance with instructions approved by the holder of the USA type certificate, the Authority or an appropriate CAR 35 authorised person.                                                                                                                                                                                                                                                                                                        |\n|                | Note 1: Colour contrast dye penetrant used in accordance with Appendix II toCAO 108.10 is an approved inspection procedure.                                                                                                                                                                                                                                                                                                                                                         |\n|                | Note 2: Cracking in these areas may be exacerbated by degradation of the control system stiffness (eg due to pivot bearing wear) and by aileron deflection during ground handling and pre-flight inspection.                                                                                                                                                                                                                                                                        |\n| Compliance:    | Inspect before 5000 hours aileron time in service, and thereafter at intervals not exceeding 500 hours aileron time in service.                                                                                                                                                                                                                                                                                                                                                     |\n|                | Compliance with Amendment 1 of this airworthiness directive constitutes compliance with this Amendment.                                                                                                                                                                                                                                                                                                                                                                             |\n\n|             | This Amendment becomes effective on 12 February 2009.                                                                                                                                                                                                                                                                          |\n| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Background: | Numerous reports have been received of fatigue cracking in the aileron spar, spar doubler, and rib flanges, which appear to be caused by high out-of-plane stresses. Cracking in these areas will degrade the strength of the hinge attachment and may have an adverse affect on the aileron flutter characteristics.          |\n|             | Amendment 1 was raised to alleviate the requirement to repetitively dismantle structure which shows no sign of defect. As a result of service experience, visual inspection requirements have been upgraded to a recognised dye penetrant inspection procedure, at shorter intervals, and additional areas have been included. |\n|             | Amendment 2 is raised to add paragraph 2(b) and to update the Compliance paragraph.                                                                                                                                                                                                                                            |\n\n![](image.001.png)  \nDavid Punshon  \nDelegate of the Civil Aviation Safety Authority\n\n23 December 2008","sortOrder":0},{"sectionNumber":"AD/PA-31/118 Amdt 2","sectionType":"part","heading":"AD/PA-31/118 Amdt 2","content":"## AD/PA-31/118 Amdt 2","sortOrder":1},{"sectionNumber":"Aileron Spar","sectionType":"part","heading":"Aileron Spar","content":"## Aileron Spar","sortOrder":2},{"sectionNumber":"2/2009","sectionType":"part","heading":"2/2009","content":"## 2/2009","sortOrder":3}],"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"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"The directive's scope was narrowed and refined since the original: Amendment 1 reduced repetitive dismantling where no defect is found, upgraded visual inspections to a recognised dye‑penetrant procedure at shorter intervals and added inspection areas; Amendment 2 added an explicit repair‑approval path (paragraph 2(b)) and updated the Compliance timing (Background; Requirement; Compliance)."},"complexity_factors":["Technical inspection method required (dye penetrant) increases specialist skill and tooling needs (Requirement 1(a); Note 1).","Physical disassembly/dismantling of ailerons and brackets when defects are suspected adds labour, downtime and access complexity (Requirement 1(a); 2(a)).","Repeated, relatively short compliance interval (initial before 5,000 hours, then every 500 hours) creates recurring maintenance burden (Compliance).","Alternative inspection scheme may be used but requires Authority approval, introducing regulatory discretion and potential delay (Requirement 1(b)).","Repair approvals may come from multiple authorities (USA type‑certificate holder, the Authority or CAR 35 authorised person), creating coordination and conformity complexity (Requirement 2(b)).","Equivalence clause with Amendment 1 means operators must track amendment history to confirm compliance status (Compliance)."],"plain_english_summary":"This directive requires operators of all Piper PA‑31 series aeroplanes to inspect both left and right ailerons for fatigue cracking of the spar, spar doubler and rib flanges. It generally requires removal of the ailerons and a dye‑penetrant inspection of hinge and horn bracket attachment areas (or an Authority‑approved alternative), and repair where cracking is found. Inspections are due before 5,000 hours aileron time and then every 500 hours; repairs must follow instructions approved by the USA type‑certificate holder, the Authority or a CAR 35 authorised person."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":true,"description":"Originally focused on visual inspection of aileron spar cracking. Amendment 1 reduced dismantling requirements for defect-free aircraft. Amendment 2 (this version) expands scope by: (1) adding explicit repair authority requirements (paragraph 2(b)), (2) upgrading from visual to mandatory dye penetrant inspection, (3) shortening inspection intervals, and (4) expanding inspection areas. The directive has evolved from basic crack detection to a comprehensive inspection and repair regime."},"complexity_factors":["Short, single-purpose document (2 pages) with clear mechanical instructions","Limited defined terms (only 'Authority' implied, 'CAR 35 authorised person' referenced)","Simple conditional structure: if-then logic for crack detection (Requirement 2)","Single cross-reference to CAO 108.10 Appendix II for inspection procedure standards","Some technical aviation terminology (spar, doubler, rib flange, dye penetrant) but explained in context","Compliance calculation requires tracking 'aileron time in service' — a specific flight hour metric"],"plain_english_summary":"This AD mandates dye‑penetrant inspection of the aileron spar, doubler and rib flanges on all Piper PA‑31 aeroplanes, with removal and approved repair if cracking is found; initial inspection is required before 5,000 aileron flight hours and then every 500 hours. \n\nIt affects PA‑31 owners, operators and maintenance organisations and tightens checks because fatigue cracks missed by visual inspection can weaken the hinge and lead to dangerous aileron flutter."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-31-118-amdt-2-aileron-spar","history":"/api/acts/ad-pa-31-118-amdt-2-aileron-spar/history","analysis":"/api/acts/ad-pa-31-118-amdt-2-aileron-spar/analysis","conflicts":"/api/acts/ad-pa-31-118-amdt-2-aileron-spar/conflicts","importantCases":"/api/acts/ad-pa-31-118-amdt-2-aileron-spar/important-cases","documents":"/api/acts/ad-pa-31-118-amdt-2-aileron-spar/documents"}}