{"id":"F2006B04937","name":"AD/CESSNA 150/39 - Rudder Pedal Torque Tube","slug":"ad-cessna-150-39-rudder-pedal-torque-tube","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44782,"registerId":"commonwealth-F2006B04937-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 150/39 - Rudder Pedal Torque Tube","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 150, F150, 152 & F152 Series Aeroplanes\n\n \n\nAD/CESSNA 150/39 Rudder Pedal Torque Tube 4/84\n\nApplicability: All models listed in Cessna Service Information Letter SE83-31 which have not been modified in accordance with that document.\n\n \n\nRequirement: Visually inspect the rudder pedal torque tubes for cracking in the vicinity of the welded joints between the torque tube and the pedal arm spigots.\n\n \n\nCompliance: Prior to issue of the next Maintenance Release after 30 April 1984, and thereafter at each issue of a new Maintenance Release.\n\n \n\nBackground: Several failures of rudder pedal torque tubes have occurred in Cessna 150 series aircraft causing loss of rudder and braking control.\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\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical failure mode in a specific aircraft series. It has not expanded beyond its original purpose of mandating inspections for rudder pedal torque tube cracks."},"complexity_factors":["Very short document (under 200 words)","Only 4 defined elements: applicability, requirement, compliance, and background","Single, straightforward inspection requirement with clear timing","No cross-references to other legislation beyond a single Cessna service document","No conditional logic or nested exceptions — applies to all listed models unless already modified"],"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:**\nIt requires owners and operators of certain **Cessna 150 series aeroplanes** (including models 150, F150, 152 and F152) to visually inspect a specific part called the **rudder pedal torque tube** — the metal tube that connects your foot pedals to the rudder and brakes.\n\n**The problem:**\nThe welded joints where the pedal arms attach to this tube have been cracking and failing. When this happens, pilots lose control of the rudder and brakes — obviously dangerous.\n\n**Who must act:**\nAnyone who owns or operates one of these Cessna models that hasn't already been fixed according to Cessna's Service Information Letter SE83-31.\n\n**What they must do:**\n- **First check:** Before the aircraft's next Maintenance Release (a legal document saying the plane is safe to fly) after 30 April 1984\n- **Ongoing checks:** Every time a new Maintenance Release is issued (typically annually)\n\n**Why it matters:**\nThis directive prevents catastrophic loss of aircraft control. The repeated inspection requirement ensures cracks are caught before they cause complete failure."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive’s scope, as set out in the text, applies to the models listed in Service Information Letter SE83-31 that have not been modified per that document, and requires visual inspections prior to the next Maintenance Release after 30 April 1984 and at each subsequent Maintenance Release (Applicability; Compliance). The published text shows no alteration or expansion of that scope beyond these stated limits."},"complexity_factors":["Narrow applicability tied to models listed in Cessna Service Information Letter SE83-31 (Applicability)","Simple required action (visual inspection) focused on a specific joint area (Requirement)","Recurring compliance schedule tied to each Maintenance Release, creating ongoing obligation (Compliance)","Directive text does not specify corrective actions or detailed inspection acceptance criteria—requires consultation of maintenance instructions or service letter for follow-up (Requirement; Applicability)","Safety-critical context because failures caused loss of rudder and braking control (Background)"],"plain_english_summary":"### What this directive does\n\nThis airworthiness directive requires owners/operators of certain Cessna 150/152 series aeroplanes to visually inspect the rudder pedal torque tubes for cracks near the welded joints between the torque tube and the pedal arm spigots (Requirement). The inspection is to be done before the next Maintenance Release issued after 30 April 1984 and then again each time a new Maintenance Release is issued thereafter (Compliance). The directive applies only to the models listed in Cessna Service Information Letter SE83-31 that have not already been modified in accordance with that document (Applicability).\n\n### Who it affects and who decides\n\n- The Civil Aviation Safety Authority is the issuing authority listed on the directive (header).\n- Aircraft owners/operators and their maintenance organisations are responsible for carrying out the inspections and for timing them to coincide with Maintenance Releases (Applicability; Compliance).\n\n### Why it matters\n\nThe directive was issued because several failures of rudder pedal torque tubes occurred in Cessna 150 series aircraft, causing loss of rudder and braking control (Background). The inspection is intended to find cracking at the welded joints before such failures occur (Requirement; Background).\n\n### How it works mechanically\n\n- Applicability: Only aircraft of the models listed in Service Information Letter SE83-31 are covered, and only if they have not been modified according to that service letter (Applicability).\n- Action required: A visual inspection specifically focused on the welded joint area between the torque tube and pedal arm spigots (Requirement).\n- Timing: Inspect before the next Maintenance Release after 30 April 1984 and then at every subsequent issue of a Maintenance Release (Compliance).\n\n### Costs, incentives and implementation notes\n\n- Who pays: Operators/owners and their maintenance providers bear the cost of performing the inspections and any follow-up work that results from them (Requirement; Compliance).\n- Incentives: The requirement creates an incentive for owners/operators either to comply with recurring inspections or to modify the torque tube per SE83-31 so the aircraft falls outside the directive’s applicability (Applicability).\n- Compliance burden: The directive mandates recurring inspections tied to the administrative event of issuing a Maintenance Release, which creates an ongoing, scheduled compliance obligation (Compliance).\n- Discretion and detail: The directive specifies visual inspection and the location to inspect, but does not itself set out corrective actions or detailed inspection acceptance criteria in the text provided here; operators will need to consult relevant maintenance instructions or the cited service letter for modification status and for any prescribed repairs (Requirement; Applicability).\n- Risk and trade-offs: The directive targets a specific known failure mode (Background). Implementing repeated visual inspections imposes routine maintenance time and cost; electing to modify an affected aircraft per the service letter may remove the inspection obligation but has its own cost and operational implications (Applicability; Compliance).\n\nSources within the directive: (Applicability), (Requirement), (Compliance), (Background)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-150-39-rudder-pedal-torque-tube","history":"/api/acts/ad-cessna-150-39-rudder-pedal-torque-tube/history","analysis":"/api/acts/ad-cessna-150-39-rudder-pedal-torque-tube/analysis","conflicts":"/api/acts/ad-cessna-150-39-rudder-pedal-torque-tube/conflicts","importantCases":"/api/acts/ad-cessna-150-39-rudder-pedal-torque-tube/important-cases","documents":"/api/acts/ad-cessna-150-39-rudder-pedal-torque-tube/documents"}}