{"id":"F2006B04589","name":"AD/BELL 212/57 - Hydraulic Servo Actuator Shoulder Bolt","slug":"ad-bell-212-57-hydraulic-servo-actuator-shoulder-bolt","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44326,"registerId":"commonwealth-F2006B04589-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 212/57 - Hydraulic Servo Actuator Shoulder Bolt","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nBell Helicopter Textron 212 Series Helicopters\n\nAD/BELL 212/57 Hydraulic Servo Actuator Shoulder Bolt 13/95\n\nApplicability: All Bell Helicopter Textron 212 Series Helicopters S/N 30501 through 30999, 31110\n\nthrough 31311, 32101 through 32142 and 35001 through 35089 which have servos installed that have been overhauled or repaired by a facility not approved by HR Textron.\n\nRequirement: Unless previously carried out action in accordance with Bell ASB 212-95-98 Revision A.\n\nCompliance: Within 25 hours time in service from 7 December 1995 or by 31 January 1996, whichever occurs first.\n\nBackground: Bell Textron has advised that unauthorised rework/repair of the shoulder bolts may have been carried out. An inspection of the shoulder bolts for possible unauthorised chrome plating is required.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive applies to the specific set of Bell 212 serial numbers and to servos overhauled or repaired by non‑approved facilities, and it requires inspection per the referenced Bell ASB. The text does not expand or narrow that scope beyond these stated limits, so the scope has not changed from the stated intent within the instrument (Applicability / Requirement / Background)."},"complexity_factors":["Narrow applicability by helicopter serial numbers and by whether servos were overhauled/repaired by a non‑approved facility (Applicability)","Requirement refers to an external technical document (Bell ASB 212-95-98 Revision A), creating a dependency on that bulletin for procedural detail (Requirement)","Short and specific compliance window (25 hours from 7 Dec 1995 or by 31 Jan 1996) concentrates workload and scheduling demands (Compliance)","Compliance requires verification of maintenance history/approval status of the repair facility, which may be administratively burdensome","Technical nature of the inspection (looking for unauthorised chrome plating) may require specialist skills or access to parts (Background / Requirement)"],"plain_english_summary":"What this instrument does, in plain terms:\n\n- It orders an inspection of a particular part (the shoulder bolts in hydraulic servo actuators) on a defined set of Bell 212 helicopters. This inspection applies only to helicopters with the serial numbers listed and only where the servos installed have been overhauled or repaired by a facility that is not approved by HR Textron (Applicability).\n\n- The inspection must be done in the manner described in Bell Alert Service Bulletin (ASB) 212-95-98 Revision A, unless that action has already been completed (Requirement).\n\n- The inspection must be carried out promptly: within 25 hours time-in-service from 7 December 1995, or by 31 January 1996, whichever comes first (Compliance).\n\nWho this affects and who pays:\n\n- Operators and owners of the affected Bell 212 helicopters are responsible for making sure the inspection is done (Applicability / Requirement). They bear the time, labour and any parts cost of compliance, and may incur aircraft downtime while the inspection or any corrective work is performed (Compliance).\n\nWhat it changes about behaviour and incentives:\n\n- Operators must check maintenance records to identify whether the installed servos were overhauled or repaired by a non‑approved facility; if they were, the required inspection follows (Applicability). That record-checking and the inspection itself create an operational incentive to use approved repair facilities in future because non‑approved repairs trigger this mandatory action.\n\n- The required action is specified by reference to Bell ASB 212-95-98 Revision A, so compliance depends on following that external technical procedure (Requirement).\n\nWhy the regulator required it (stated reason):\n\n- Bell Textron advised that unauthorised rework or repair of the shoulder bolts may have been performed, creating a risk that requires inspection for possible unauthorised chrome plating of the bolts (Background).\n\nPractical implementation points and trade-offs to note (source‑grounded):\n\n- Determining who pays and what must be done is mechanical: operators check serial numbers and maintenance history, then carry out the inspection per the referenced ASB if the servos were worked on by a non‑approved facility (Applicability / Requirement).\n\n- The directive sets a short compliance window (25 flight hours from 7 December 1995 or by 31 January 1996), which concentrates the operational and labour cost into an immediate period and may cause scheduling or downtime pressures (Compliance).\n\n- The directive relies on an external technical document (Bell ASB 212-95-98 Revision A) for the inspection procedure. That creates a compliance dependency: operators must obtain and follow the ASB to satisfy the directive (Requirement).\n\n- The inspection focuses on detecting possible unauthorised chrome plating on the shoulder bolts; performing that inspection may require physical access and technical judgement consistent with the ASB (Background / Requirement).\n\nSections cited: Applicability; Requirement; Compliance; Background."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-limited safety directive addressing a specific manufacturing defect/repair issue. It has not expanded beyond its original purpose of ensuring proper inspection of potentially defective shoulder bolts."},"complexity_factors":["Single, specific mechanical component addressed (shoulder bolts in hydraulic servos)","Narrow applicability criteria (specific serial number ranges plus specific repair history)","Single compliance action required (follow existing Bell service bulletin)","Simple time-based compliance window (25 hours or fixed date)","No defined terms section, no cross-references to other legislation beyond the parent regulations","Background explanation provided in plain language"],"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 Bell 212 helicopters.\n\n**What it does:**\n- Requires owners/operators to inspect the **hydraulic servo actuator shoulder bolts** on certain Bell 212 helicopters\n- Specifically looks for **unauthorised chrome plating** that may have been applied during improper repairs\n\n**Who it affects:**\n- Owners and operators of Bell 212 helicopters with serial numbers: 30501-30999, 31110-31311, 32101-32142, and 35001-35089\n- Only applies if the helicopter's servos were overhauled or repaired by a facility **not approved by HR Textron** (the manufacturer)\n\n**What must be done:**\n- Follow the instructions in **Bell Alert Service Bulletin 212-95-98 Revision A**\n- Complete the inspection within **25 flight hours** from 7 December 1995 **or** by 31 January 1996 — whichever comes first\n\n**Why it matters:**\nUnauthorised repairs to critical flight control components can compromise safety. Chrome plating done improperly can cause hydrogen embrittlement or dimensional issues, potentially leading to bolt failure and loss of hydraulic control."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-212-57-hydraulic-servo-actuator-shoulder-bolt","history":"/api/acts/ad-bell-212-57-hydraulic-servo-actuator-shoulder-bolt/history","analysis":"/api/acts/ad-bell-212-57-hydraulic-servo-actuator-shoulder-bolt/analysis","conflicts":"/api/acts/ad-bell-212-57-hydraulic-servo-actuator-shoulder-bolt/conflicts","importantCases":"/api/acts/ad-bell-212-57-hydraulic-servo-actuator-shoulder-bolt/important-cases","documents":"/api/acts/ad-bell-212-57-hydraulic-servo-actuator-shoulder-bolt/documents"}}