{"id":"F2006B05006","name":"AD/CESSNA 177/11 Amdt 1 - Stabilator Attachment Angles","slug":"ad-cessna-177-11-amdt-1-stabilator-attachment-angles","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44916,"registerId":"commonwealth-F2006B05006-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 177/11 Amdt 1 - Stabilator Attachment Angles","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Cessna 177 Series Aeroplanes\n\n \n\nAD/CESSNA 177/11\n\nAmdt 1\n\n\nStabilator Attachment Angles 4/72\n\n \n\nApplicability: Model 177 with S/Nos. 17700001 to 17701164 and Model 177A with S/Nos.\n\n17701165 to 17701370 not fitted with Cessna Kit No. SK 177-11 (Ref. Cessna SB SE70-32).\n\n \n\nRequirement: 1. Remove the fuselage tail stinger and inspect the stabilator attachment angles P/No.\n\n1712108 for cracking using a dye- penetrant method.\n\n \n\n2. Modify the stabilator attachments by fitting Cessna Kit No. SK 177-11.\n\n \n\nCompliance: For para. 1 - Within 50 hours time in service after 29 January 1971 and thereafter at intervals not exceeding 50 hours time in service.\n\n \n\nFor para. 2 - Within 100 hours time in service after 28 April 1972.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, targeted safety directive addressing a specific structural defect in specific aircraft. It has not expanded beyond its original purpose of ensuring stabilator attachment integrity."},"complexity_factors":["Very short document (approximately 200 words)","Only 2 defined applicability criteria (serial number ranges and kit exclusion)","2 straightforward requirements with clear compliance deadlines","No cross-references to other legislation or regulations","No nested exceptions or conditional logic","Single subject matter (one specific aircraft part on specific models)","Technical but precise language (part numbers, serial numbers, kit numbers)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\nThis directive requires owners and operators of certain **Cessna 177 and 177A aircraft** to inspect and modify a critical part of the tail section called the **stabilator attachment angles**. The stabilator is a combined horizontal stabilizer and elevator (the moving part that controls the aircraft's pitch). The attachment angles are the metal brackets that connect this control surface to the fuselage.\n\n**Who it affects:**\n- Cessna Model 177 aircraft with serial numbers 17700001 through 17701164\n- Cessna Model 177A aircraft with serial numbers 17701165 through 17701370\n- **Only if** these aircraft have **not** already been fitted with Cessna Kit No. SK 177-11\n\n**What must be done:**\n1. **Inspection:** Remove the tail section (\"fuselage tail stinger\") and check the attachment brackets (part number 1712108) for cracks using a special dye-penetrant testing method. This must happen every 50 hours of flight time.\n2. **Modification:** Install a specific Cessna repair kit (SK 177-11) to strengthen the attachment within 100 hours of flight time.\n\n**Why it matters:**\nCracked attachment angles could cause the stabilator to fail in flight, leading to loss of pitch control and potentially a crash. This AD was issued to prevent catastrophic structural failure."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The instrument is titled as Amendment 1 (AD/CESSNA 177/11 Amdt 1), and the text contains both an inspection mandate (para.1) and a required modification by fitting Kit SK 177-11 (para.2). Because the original AD text is not supplied, specific prior scope changes cannot be fully reconstructed here; the amendment label and presence of a mandated kit fit indicate the AD’s scope has been altered from whatever preceded it."},"complexity_factors":["Narrow applicability by serial number and exclusion if Kit SK 177-11 already fitted (Applicability)","Two discrete technical actions: dye‑penetrant crack inspection requiring removal of tail stinger (Requirement 1)","Mandatory modification by fitting a specific manufacturer kit (Requirement 2)","Defined compliance intervals and recurring inspection frequency (Compliance: para.1 and para.2)","Operational impacts: downtime, parts supply and installation labour borne by owners/operators (inferred from mandatory work and kit requirement)"],"plain_english_summary":"Mechanically, this airworthiness directive requires removal of the tail stinger to perform a dye‑penetrant crack inspection of the stabilator attachment angles (P/No. 1712108) and, for affected aeroplanes, modification by fitting Cessna Kit SK 177-11. It applies to specified Cessna 177/177A serial numbers not already fitted with that kit. Compliance deadlines set recurring 50‑hour inspections (para.1) and a one‑time modification within 100 hours (para.2), shifting inspection, parts and labour costs onto operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-177-11-amdt-1-stabilator-attachment-angles","history":"/api/acts/ad-cessna-177-11-amdt-1-stabilator-attachment-angles/history","analysis":"/api/acts/ad-cessna-177-11-amdt-1-stabilator-attachment-angles/analysis","conflicts":"/api/acts/ad-cessna-177-11-amdt-1-stabilator-attachment-angles/conflicts","importantCases":"/api/acts/ad-cessna-177-11-amdt-1-stabilator-attachment-angles/important-cases","documents":"/api/acts/ad-cessna-177-11-amdt-1-stabilator-attachment-angles/documents"}}