{"id":"F2005L02419","name":"AD/CESSNA 336/11 Amdt 3 - Wing Front and Rear Spars - Inspection","slug":"ad-cessna-336-11-amdt-3-wing-front-and-rear-spars-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":36951,"registerId":"commonwealth-F2005L02419-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Cessna 336 Series Aeroplanes","sectionType":"division","heading":"Cessna 336 Series Aeroplanes","content":"### Cessna 336 Series Aeroplanes\n\n| AD/CESSNA 336/11 Amdt 3 | Wing Front and RearSpars - Inspection | 10/2005 |\n| ----------------------- | ------------------------------------- | ------- |\n\n| Applicability: | Models 336 with the following serial numbers 336-0001 through 336-0195.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |\n| -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Inspect the front and rear spars for cracking in accordance with Cessna SL ME78-2 Supplement No. 1 except that in connection with the front spar inspection the eddy current test sensitivity shall be established so that a 10% full scale meter deflection is obtained from a slot .030\" + .003\" deep, .060\" + .003\" long and .010\" maximum width, machined in the wall of a 3/16\" diameter hole in an aluminium alloy test block.Note 1: FAA AD 78-09-05 also refers.Note 2: A suitable test block is Nortec Part No. TB-12.Note 3: Scoring of bolt holes can cause spurious eddy current indications of cracking and may be the cause of future fatigue crack initiations. Great care must therefore be taken when removing the subject bolts. |\n| Compliance:    | Inspect both the front and rear spars in accordance with the times specified for the rear spar in “Action Required” Section of Cessna SL ME78-2 Supplement No. 1 except that for aircraft incorporating Robertson Aircraft Corporation Modification to United States STC 1627 WE a reduction of 1000 hours in the inspection threshold and 100 hours in inspection intervals shall apply. This exception is subject to change should fatigue substantiating data on the Robertson conversion be supplied to the Authority.                                                                                                                                                                                                                         |\n|                | This Amendment becomes effective on 29 September 2005.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |\n| Background:    | Amendment 2 was issued to clarify the eddy current test block specifications.This amendment is issued to clearly define which serial numbered aircraft are affected by this AD.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n8 August 2005","sortOrder":0},{"sectionNumber":"AD/CESSNA 336/11 Amdt 3","sectionType":"part","heading":"AD/CESSNA 336/11 Amdt 3","content":"## AD/CESSNA 336/11 Amdt 3","sortOrder":1},{"sectionNumber":"Wing Front and RearSpars - Inspection","sectionType":"part","heading":"Wing Front and RearSpars - Inspection","content":"## Wing Front and Rear  \nSpars - Inspection","sortOrder":2},{"sectionNumber":"10/2005","sectionType":"part","heading":"10/2005","content":"## 10/2005","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":true,"description":"This amendment narrows and clarifies applicability by specifying affected serial numbers (336-0001 through 336-0195) rather than leaving applicability ambiguous (Background). It also imposes a concrete test-block calibration and names Nortec TB-12, and introduces a reduced inspection threshold/interval for aircraft with the Robertson/STC 1627 WE conversion (Compliance). The amendment takes effect 29 September 2005."},"complexity_factors":["Detailed nondestructive-test calibration requirement: eddy-current sensitivity set to 10% full-scale from a slot with precise dimensions (Requirement).","Dependence on an external service document for action times: inspection intervals reference Cessna SL ME78-2 Supplement No.1 (Compliance).","Specific test-block identification and material reliance: Nortec Part No. TB-12 named as suitable (Requirement / Note 2).","Exception for Robertson/STC 1627 WE conversions that reduces threshold and interval (Compliance) and is conditional on future fatigue data.","Cross-reference to FAA AD 78-09-05 introduces additional external regulatory linkage (Requirement / Note 1).","Operational caution about bolt-hole scoring causing spurious indications and fatigue risk, increasing inspection and removal care (Requirement / Note 3).","Compliance timing tied to the rear-spar schedule in the referenced service letter rather than a single calendar-based regimen (Compliance)."],"plain_english_summary":"Requires eddy-current inspection of the front and rear wing spars on Cessna 336 aeroplanes serial numbers 336-0001 through 336-0195, with a specified test-block and calibration (10% full-scale deflection from a defined slot). It ties inspection timing to Cessna SL ME78-2 Supplement No.1, shortens thresholds for aircraft with the Robertson/STC 1627 WE conversion, and is intended to detect and prevent spar cracking. Owners/operators and maintenance providers must carry out and pay for the inspections."},"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":4,"scope_assessment":{"changed":false,"description":"This amendment represents a minor administrative clarification rather than scope expansion. The Background section explicitly states this amendment merely defines which serial numbers are affected — a narrowing/specification of existing scope, not an expansion beyond original intent. The core safety purpose (wing spar inspection for cracking) remains unchanged from previous amendments."},"complexity_factors":["Technical aviation terminology throughout (eddy current testing, spars, STC — Supplemental Type Certificate)","Precise engineering specifications with tolerances (0.030\" + 0.003\" deep, etc.)","Cross-reference to external documents (Cessna SL ME78-2 Supplement No. 1, FAA AD 78-09-05, Nortec Part No. TB-12)","Conditional compliance requirements based on aircraft modification status (Robertson Aircraft Corporation Modification to US STC 1627 WE)","Nested exception with open-ended condition ('subject to change should fatigue substantiating data... be supplied')","Dual effective dates: compliance timing tied to flight hours AND amendment effective date of 29 September 2005"],"plain_english_summary":"Owners/operators of early Cessna 336s (serials 336‑0001 through 336‑0195) must carry out mandated eddy‑current inspections of front and rear wing spars to detect fatigue cracking, with equipment calibrated to find cracks as small as 0.030 inches and inspection intervals set by the AD (shorter by 1,000 hours for aircraft with a specific Robertson modification).\n\nThis matters because spar cracks can cause catastrophic structural failure; mechanics must avoid scoring bolt holes, which can mask or create cracks."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-336-11-amdt-3-wing-front-and-rear-spars-inspection","history":"/api/acts/ad-cessna-336-11-amdt-3-wing-front-and-rear-spars-inspection/history","analysis":"/api/acts/ad-cessna-336-11-amdt-3-wing-front-and-rear-spars-inspection/analysis","conflicts":"/api/acts/ad-cessna-336-11-amdt-3-wing-front-and-rear-spars-inspection/conflicts","importantCases":"/api/acts/ad-cessna-336-11-amdt-3-wing-front-and-rear-spars-inspection/important-cases","documents":"/api/acts/ad-cessna-336-11-amdt-3-wing-front-and-rear-spars-inspection/documents"}}