{"id":"F2007L04637","name":"AD/CIRRUS/8 - Wingtip Drain Hole","slug":"ad-cirrus-8-wingtip-drain-hole","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":70948,"registerId":"commonwealth-F2007L04637-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Cirrus Design SR20 and SR22 Series Aerop","sectionType":"division","heading":"Cirrus Design SR20 and SR22 Series Aeroplanes","content":"### Cirrus Design SR20 and SR22 Series Aeroplanes\n\n| AD/CIRRUS/8 | Wingtip Drain Hole | 2/2008 DM |\n| ----------- | ------------------ | --------- |\n\n| Applicability: | Model SR22 aircraft, serial numbers 2334, 2420, and 2438 through 2749.                                                                                                                                                                                                                                                                                                                                                                                            |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Install a drain hole in the left and right outboard wing tips in accordance with Cirrus Design Service Bulletin SB 2X-57-08 original issue, or later FAA approved revision.Note: FAA AD 2007-24-13 Amdt 39-15279 refers.                                                                                                                                                                                                                                          |\n| Compliance:    | Within the next 10 hours time in service or within 30 days after 7 December 2007, whichever occurs first.                                                                                                                                                                                                                                                                                                                                                         |\n|                | This Airworthiness Directive becomes effective on 7 December 2007.                                                                                                                                                                                                                                                                                                                                                                                                |\n| Background:    | The FAA received reports of pilots’ inability to move the aileron control without using excessive force when flying in freezing conditions. Moisture from a prior rain shower had entered through a gap at the interface of the left and right outboard wing tips and wing structure. The moisture travelled along the aft wing shear web, accumulated below the aileron control pulley, and froze at an altitude with an outside air temperature below freezing. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n4 December 2007","sortOrder":0},{"sectionNumber":"AD/CIRRUS/8","sectionType":"part","heading":"AD/CIRRUS/8","content":"## AD/CIRRUS/8","sortOrder":1},{"sectionNumber":"Wingtip Drain Hole","sectionType":"part","heading":"Wingtip Drain Hole","content":"## Wingtip Drain Hole","sortOrder":2},{"sectionNumber":"2/2008 DM","sectionType":"part","heading":"2/2008 DM","content":"## 2/2008 DM","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive addressing a specific mechanical defect in a specific aircraft type. It has not expanded beyond its original purpose of mandating a physical modification to prevent control system icing."},"complexity_factors":["Very short document (approximately 200 words of substantive content)","Only 3 defined elements: specific aircraft model (SR22), specific serial number range, and reference to external technical document (Service Bulletin)","Single unconditional requirement with no exceptions or alternative compliance methods","No internal cross-references to other legislation or regulations","Simple binary applicability test (is your aircraft in this serial number list?)","Straightforward compliance deadline (whichever occurs first of two clear triggers)"],"plain_english_summary":"This CASA Airworthiness Directive mandates owners/operators of specified Cirrus SR22 serials (2334, 2420, 2438–2749) to drill small drain holes in both wingtips to prevent rainwater pooling and freezing around the aileron control pulley, which can jam roll controls. Compliance required per Cirrus Service Bulletin SB 2X-57-08 (or FAA-approved later revision), within 10 flight hours or 30 days after 7 December 2007."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive's scope aligns with its stated safety purpose: it targets moisture ingress and potential aileron freezing on a defined set of SR22 serial numbers by mandating installation of wingtip drain holes per a specified service bulletin. There is no text indicating expansion or narrowing of that remedial scope beyond the stated applicability and compliance terms."},"complexity_factors":["Very narrow technical scope: applies only to Model SR22 aircraft with specific serial numbers (Applicability).","Single, discrete corrective action specified: install drain holes per Cirrus Service Bulletin SB 2X-57-08 or later FAA‑approved revision (Requirement).","Short mandatory compliance window creates operational scheduling pressure for owners/operators (Compliance).","Dependence on an external technical document (Service Bulletin) and possible later FAA revisions creates a small interpretive dependency (Requirement).","Safety rationale is specific and evidence-based in the AD (Background), reducing need for broader policy interpretation.","Authority and issuance are clear (CASA delegate; cross-reference to FAA AD), so administrative discretion is limited (front page signature and note)."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of specific Cirrus SR22 aircraft (serials 2334, 2420, 2438–2749) to install drain holes in the left and right outboard wingtips, following Cirrus Service Bulletin SB 2X-57-08 or a later FAA‑approved revision, to stop water ingress that can freeze and jam the aileron. It must be completed within the next 10 hours time‑in‑service or within 30 days after 7 December 2007 (whichever is first). Costs and action fall to the aircraft owner/operator; CASA issued the directive (Requirement; Compliance; Background)."},"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-cirrus-8-wingtip-drain-hole","history":"/api/acts/ad-cirrus-8-wingtip-drain-hole/history","analysis":"/api/acts/ad-cirrus-8-wingtip-drain-hole/analysis","conflicts":"/api/acts/ad-cirrus-8-wingtip-drain-hole/conflicts","importantCases":"/api/acts/ad-cirrus-8-wingtip-drain-hole/important-cases","documents":"/api/acts/ad-cirrus-8-wingtip-drain-hole/documents"}}