{"id":"F2006B05369","name":"AD/P68/42 - Wing Upper Skin Stringers","slug":"ad-p68-42-wing-upper-skin-stringers","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":45939,"registerId":"commonwealth-F2006B05369-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/P68/42 - Wing Upper Skin Stringers","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nPartenavia P68 Series Aeroplanes\n\nAD/P68/42 Wing Upper Skin Stringers 2/96\n\nApplicability: All P68 series aircraft up to S/N 400 inclusive.\n\nRequirement: 1. Modify and inspect the wing and engine nacelle between ribs 6 and 8 in accordance with paragraphs 2.1 and 2.2 of Partenavia Service Bulletin No 93.\n\n2. Modify and inspect the wing upper surface between ribs 6 and 8 in accordance with paragraphs 2.3 and 2.4 of Partenavia Service Bulletin No 93.\n\nCompliance: 1. Action in accordance with Requirement 1 before 100 hours time in service after 1 February 1996 or before 500 hours time in service, whichever occurs later. Re- inspect at intervals not to exceed 300 hours time in service until modified in accordance with Requirement 2.\n\nFor aircraft modified in accordance with Requirement 2, re-inspect at intervals not to exceed 500 hours time in service.\n\n2. Action in accordance with Requirement 2 before further flight if cracked stringers are found during inspection in accordance with Requirement 1. Re-inspect at intervals not to exceed 2000 hours time in service.\n\nBackground: Several cases of cracking of the wing upper skin stringers have been reported to the manufacturer. On one aircraft in Australia, during re-assembly after inspection in accordance with AD/P68/28, all four stringers were found to be cracked on both sides of the wing. This Directive requires installation of access panels for inspection and replacement of all stringers if any are found cracked.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive addressing a specific structural defect in a specific aircraft series. It has not expanded beyond its original safety purpose."},"complexity_factors":["Short, single-purpose directive (approximately 250 words)","Only 4 defined elements: Applicability, Requirement, Compliance, and Background","Simple conditional logic: two alternative compliance paths depending on whether Requirement 1 or 2 is followed","Cross-reference to external document (Partenavia Service Bulletin No 93) without reproducing its content","Time-based compliance triggers using 'whichever occurs later' construction","No nested exceptions or definitional sections"],"plain_english_summary":"Australia's CASA has issued a mandatory Airworthiness Directive for Partenavia P68 aeroplanes (serial numbers 400 and below) requiring inspection and modification of the wing upper skin/stringers per Service Bulletin No. 93, installation of access panels, and replacement of any cracked stringers.  \n\nThis addresses discovered multi‑stringer cracking that risks wing structural failure. Initial work is due within 100 flight hours after Feb 1996 or before 500 total hours (whichever is later); any cracked stringer must be repaired before further flight, with scheduled follow‑up inspections thereafter."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":false,"description":"The text does not indicate a change from an earlier stated scope or intent. It sets a clear applicability (P68 up to S/N 400) and prescribes inspections, modifications and replacements in response to reported cracking; no language in the directive expands or narrows scope beyond those statements."},"complexity_factors":["Limited applicability: only P68 series aircraft up to S/N 400 inclusive (Applicability).","Two-tier technical requirements that reference specific paragraphs of a manufacturer Service Bulletin (Requirement 1 & 2 referencing Partenavia Service Bulletin No 93 paragraphs 2.1–2.4).","Multiple, conditional compliance deadlines: initial action required before 100 hours after 1 Feb 1996 or before 500 hours TSIL, whichever is later (Compliance 1).","Different recurring inspection intervals depending on modification status: re-inspect ≤300 hrs until Requirement 2 completed, then ≤500 hrs (Compliance 1).","Immediate mandatory upgrade if cracking found: Requirement 2 must be done before further flight if cracks discovered, with a longer re‑inspection interval thereafter (Compliance 2).","Operational impacts: installation of access panels and potential replacement of all stringers if any are cracked, creating parts, labour and downtime costs (Requirement 1 & Background).","Reliance on a manufacturer Service Bulletin for technical steps concentrates procedural detail outside the AD, requiring maintenance organisations to interpret and apply those SB paragraphs precisely (Requirement references)."],"plain_english_summary":"This Airworthiness Directive requires operators of *Partenavia P68* aircraft (serial numbers up to 400) to modify and inspect the wing upper skin stringers and the adjacent engine nacelle area per Partenavia Service Bulletin No 93, and to replace any cracked stringers. It mandates installation of inspection access panels and sets specific initial and recurring inspection intervals.\n\nThe measure responds to reported stringer cracking; owners/operators bear the cost and downtime of inspections, repairs and replacements, and maintenance organisations must carry out the specified work within the staged deadlines."},"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-p68-42-wing-upper-skin-stringers","history":"/api/acts/ad-p68-42-wing-upper-skin-stringers/history","analysis":"/api/acts/ad-p68-42-wing-upper-skin-stringers/analysis","conflicts":"/api/acts/ad-p68-42-wing-upper-skin-stringers/conflicts","importantCases":"/api/acts/ad-p68-42-wing-upper-skin-stringers/important-cases","documents":"/api/acts/ad-p68-42-wing-upper-skin-stringers/documents"}}