{"id":"F2025L00704","name":"AD/BEECH 33/41 Amdt 6 — Wing Bolt, Nut and Fitting","slug":"ad-beech-33-41-amdt-6-wing-bolt-nut-and-fitting","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":106475,"registerId":"commonwealth-F2025L00704-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Textron Aviation (Beechcraft) 33 and 35-","sectionType":"part","heading":"Textron Aviation (Beechcraft) 33 and 35-33 (Debonair/Bonanza) Series Aeroplanes","content":"# Textron Aviation (Beechcraft) 33 and 35-33 (Debonair/Bonanza) Series Aeroplanes\n\n| AD/BEECH 33/41 Amdt 6 | Wing Bolt, Nut and Fitting | 12/2025 |\n| --------------------- | -------------------------- | ------- |\n\n| Applicability: | All models of Textron Aviation (formerly Beechcraft) 33 and 35-33 series aircraft, all serial numbers. |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | 1. Remove inspection covers from wing attach fitting recesses and inspect for corrosion or loss of inhibitor. Also inspect drain holes for any blockage that would cause water or debris to accumulate.Note 1: It may be necessary to use a bright light and mirror/magnifying glass to see hard to view areas of the bolt or fittings for signs of corrosion on accessible areas of the bolt. Non accessible areas like the bolt thread encapsulated by the nut will be inhibited, so it is highly unlikely they will experience corrosion unless the general surrounding area is corroded.2. Remove and inspect wing bolts, washers, nuts and fittings in accordance with Beechcraft Maintenance Manual 36-590001-9D Revision D2 May 29, 2024 Chapter 57, as in force on the date of commencement of this AD.Note 2: The bolt torque should be checked before removal for inspection or replacement to confirm the bolt has been torqued to correct value. If the torque value is incorrect, other maintenance action may be required.Note 3: Amendment 5 of this AD referred, and this Amendment also refers, to all serial numbers within its Applicability as the type certificate holder has not updated the Beechcraft Shop manual which includes other serial number ranges. The maintenance listed above at Requirement 2 is to be utilised for all serial numbers with reference to the wing bolt, nut and fitting requirements.3. Retire wing bolts, washers and nuts from service and replace with new hardware in accordance Beechcraft Maintenance Manual 36-590001-9D Revision D2 May 29, 2024 Chapter 57, as in force on the date of commencement of this AD. Render unserviceable all hardware retired. Alternatively, as per the above aircraft maintenance manual the bolts may be maintained on condition IAW Table 201 Beechcraft Maintenance Manual 36-590001-9D Revision D2 May 29, 2024, Chapter 57, as in force on the date of commencement of this AD. |\n| Compliance: | For Requirement 1:Every 12 calendar months for all aircraft. If visible corrosion is found within the recess or on visible portion of the bolt or nuts, washers or fittings, then Requirement 2 must be accomplished before further flight. |\n| | For Requirement 2:a. For aircraft operating only in private operations:i. unless the inspection has already been accomplished in accordance with the Beechcraft 33 Maintenance Manual 33-590011-1 Revision C17 dated May 1, 1989, the Beechcraft Maintenance Manual 35-590096 Revision B22 dated 1 April 2011 or the Beechcraft Maintenance Manual 36-590001-9D Revision D2 dated May 29, 2024, each as in force on the date of commencement of this instrument (the requirement documents) within 10 years from the initial installation of the wing bolts — inspect within 100 hours’ time in service (TIS) or 12 months from the commencement date of this AD, whichever occurs first.Note 4: Installation of the wing bolts includes where they are removed for inspection purposes and re-installed.ii. re-inspect at intervals not to exceed 10 years from the previous inspection.b. For all other operational categories:i. unless the inspection has already been accomplished in accordance with any of the requirement documents within 5 years from the installation of the wing bolts — inspect within 100 hours’ TIS or 12 months from the commencement date of this AD, whichever occurs first.Note 5: Installation of the wing bolts includes where they are removed for inspection purposes and re-installed.ii. re-inspect at intervals not to exceed 5 years from the previous inspection.For Requirement 3:Before 20 years TIS after the first installation of new zero time wing bolts. Alternatively, as per the maintenance manual the bolts may be maintained on condition IAW table 201 of the Beechcraft Maintenance Manual 36-590001-9D Revision D2 May 29, 2024, Chapter 57, as in force on the date of commencement of this AD.Note 6: Always replace wing attach nuts with new items when removing the wing attach bolts for inspection.Mandatory reporting requirements:Both NIL findings of defects and confirmed defects for Requirement 2 inspection must be reported via CASA’s Defect Reporting Service, either through the online portal at:https://www.casa.gov.au/resources-and-education/our-systems/defect-report-serviceor by using Form 404 available from:https://www.casa.gov.au/defect-report |\n| | Commencement date:This AD commences on 13 July 2025. |\n| Background: | The initial issue of this Airworthiness Directive became effective on 1 February 1996 and made mandatory the inspection and replacement periods for the wing attachment hardware as detailed in the requirement document.Amendment 1 of this AD added the Note 1 to Requirement 2 and added the fittings as an item to be inspected when the wing bolts, washers and nuts are removed and inspected.Amendment 2 of this AD removed the alternative means of compliance that had been issued to allow in-situ inspection of the wing attachment bolts and nuts rather than conduct the manufacturer’s required MPI.Amendment 3 of this AD was issued to extend the compliance time for Requirement 1 by two months whilst the proposed airworthiness directive process was conducted for AD/BEECH 33/41 Amdt 4.Amendment 4 of this AD allowed for aircraft used in private operations to be visually inspected for corrosion in the exposed areas of the wing attach bolts and wing fitting recess with the inspection interval increased from 5 to 10 years, in lieu of using the manufacturer’s maintenance instructions. For all other types of operations, the inspection requirements remained unchanged, requiring inspection of the wing attach hardware and fitting recess per the manufacturer’s maintenance data.Amendment 5 of this AD was issued following a change to the Instructions for Continued Airworthiness (ICA) by the type certificate holder, increasing the life limit of the wing bolts to 20 years and only requiring a removal and visual inspection at the five-year interval.Amendment 6 of this AD follows the amendment of the Beechcraft Maintenance Manual 36-590001-9D allowing for the wing attach bolts to be maintained on condition following their 20 year in service life as an option to replacing the bolts. |\n\n![David Punshon's signature.](image.001.jpeg)\n\nDavid Punshon \nDelegate of the Civil Aviation Safety Authority\n\n13 June 2025","sortOrder":0},{"sectionNumber":"AD/BEECH 33/41 Amdt 6","sectionType":"part","heading":"AD/BEECH 33/41 Amdt 6","content":"## AD/BEECH 33/41 Amdt 6","sortOrder":1},{"sectionNumber":"Wing Bolt, Nut and Fitting","sectionType":"part","heading":"Wing Bolt, Nut and Fitting","content":"## Wing Bolt, Nut and Fitting","sortOrder":2},{"sectionNumber":"12/2025","sectionType":"part","heading":"12/2025","content":"## 12/2025","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":7,"scope_assessment":{"changed":true,"description":"Yes. Compared with earlier issuances, this amendment (Amendment 6) implements the Beechcraft Maintenance Manual change that permits maintaining wing attach bolts on condition after a 20‑year in‑service life as an alternative to mandatory replacement. Earlier amendments had changed inspection intervals (introducing a longer 10‑year option for private operations) and increased the bolt life limit to 20 years. The AD also continues to apply to all serial numbers, and introduces mandatory reporting of inspection outcomes to CASA."},"complexity_factors":["Multiple cross‑references to the Beechcraft Maintenance Manual (36-590001-9D Revision D2) that determine detailed inspection and replacement procedures","Different compliance intervals depending on operational category (private vs other) and time‑in‑service (5 vs 10 year re‑inspect cycles)","Alternative maintenance paths: mandatory replacement at life limit versus \"maintain on condition\" option introduced by the amended manual","Mandatory reporting requirement to CASA for both NIL and positive findings, adding administrative burden","Requirement to remove covers, inspect recesses and potentially use special visual aids; non‑accessible areas presumed inhibited (practical inspection limits)","Torque check and potential follow‑on maintenance if torque is incorrect, adding diagnostic steps","Obligation to render retired hardware unserviceable and replace nuts whenever bolts are removed, increasing parts and disposal costs","Applicability to all serial numbers and interaction with legacy shop/manual updates creates interpretive and records‑management complexity","Transition history of amendments (amendments 1–6) altering intervals, methods and life limits increases compliance tracking burden"],"plain_english_summary":"AD/BEECH 33/41 Amdt 6 requires owners/operators of all Beechcraft 33 and 35‑33 series aeroplanes to inspect wing attach bolts, nuts, washers and fitting recesses, remove and inspect items per the Beechcraft Maintenance Manual, and retire or replace hardware where required. It sets different inspection intervals for private versus other operations, mandates reporting of inspection results to CASA, allows maintenance‑on‑condition as an alternative after 20 years, and commences 13 July 2025. Owners/operators pay inspection, reporting and replacement costs."},"kimi_summary":{"content_quality":"ok","complexity_score":6,"scope_assessment":{"changed":true,"description":"The original 1996 directive was a straightforward safety mandate requiring periodic inspection and replacement of wing bolts. Over six amendments, the scope has expanded significantly: Amendment 4 introduced a dual-track system differentiating private from commercial operations; Amendment 5 added a 20-year life limit; and Amendment 6 (this version) introduces an 'on condition' maintenance alternative that allows indefinite extension beyond 20 years with ongoing inspections. The directive has evolved from a simple 'inspect and replace' mandate to a complex, risk-based maintenance regime with multiple compliance pathways, reporting obligations, and operational category distinctions."},"complexity_factors":["Multiple operational categories with different compliance intervals (private vs non-private operations)","Nested conditional logic: 'unless already accomplished' clauses with reference to three different historical manual versions","Cross-references to external documents (Beechcraft Maintenance Manual 36-590001-9D Revision D2) with specific revision dates","Alternative compliance pathways (replacement at 20 years OR on-condition maintenance per Table 201)","Six amendment history notes explaining evolution of requirements","Defined terms used but not explicitly defined in the instrument itself (TIS = Time In Service, IAW = In Accordance With, ICA = Instructions for Continued Airworthiness)","Mandatory reporting requirement adds administrative burden beyond physical maintenance","Specific torque-checking requirement before bolt removal creates procedural sequencing constraints"],"plain_english_summary":"This AD requires owners/operators and maintenance organisations of Beechcraft Debonair and Bonanza (models 33 and 35‑33) to inspect and eventually replace the wing attachment bolts — including regular visual checks and periodic removal/inspection of bolts — with a 20‑year nominal service life unless maintained \"on condition.\" \n\nIt matters because these bolts are flight‑critical; corrosion or fatigue could cause wing separation. All inspection results must be reported to CASA."},"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-beech-33-41-amdt-6-wing-bolt-nut-and-fitting","history":"/api/acts/ad-beech-33-41-amdt-6-wing-bolt-nut-and-fitting/history","analysis":"/api/acts/ad-beech-33-41-amdt-6-wing-bolt-nut-and-fitting/analysis","conflicts":"/api/acts/ad-beech-33-41-amdt-6-wing-bolt-nut-and-fitting/conflicts","importantCases":"/api/acts/ad-beech-33-41-amdt-6-wing-bolt-nut-and-fitting/important-cases","documents":"/api/acts/ad-beech-33-41-amdt-6-wing-bolt-nut-and-fitting/documents"}}