{"id":"F2006B04407","name":"AD/BELL 205/7 - Tail Rotor Blade Grip - Inspection","slug":"ad-bell-205-7-tail-rotor-blade-grip-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44232,"registerId":"commonwealth-F2006B04407-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 205/7 - Tail Rotor Blade Grip - Inspection","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nBell Helicopter Textron 205 Series Helicopters\n\nAD/BELL 205/7 Tail Rotor Blade Grip \\- Inspection 3/70\n\nApplicability: All model 205 series helicopters fitted with tail rotor hub assembly P/N 204-011-801- 5 or -7, or P/N 204-011-701-11, -13 or -19.\n\nRequirement: Inspect the P/N 204-011-728 or P/N 204-011-706 tail rotor blade grip assembly for minimum hardness of 70 on Rockwell “B” scale or below conductivity of 29 on international annealed copper standard. Readings should be taken adjacent to vibro etched serial number between the blade retention bolts on the grip face.\n\nNote: These tests may be accomplished using a Rockwell Harness Tester or Eddy Current Tester Magnatest FM120 or equivalent.\n\nCompliance: 1. Installed Blade Grips \\- before further flight after 3 March 1970.\n\n2. Spare Blade Grips \\- before installation on an aircraft after 3 March 1970.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue safety directive from 1970 addressing a specific metallurgical defect in specific helicopter components. It has not expanded beyond its original narrow scope of ensuring tail rotor blade grip integrity through hardness testing."},"complexity_factors":["Very short document (approximately 150 words)","Only 2 defined part number ranges (tail rotor hub assemblies and blade grip assemblies)","Single straightforward requirement with one specific test methodology","No cross-references to other legislation or regulations beyond the enabling authority (Civil Aviation Regulations 1988, Part 39)","Simple binary compliance structure (installed vs. spare parts)","No exceptions, exemptions, or conditional logic"],"plain_english_summary":"This is an **Airworthiness Directive** — essentially a mandatory safety order for aircraft owners and operators. It applies to specific **Bell 205 series helicopters** (think military-style utility helicopters, similar to the civilian version of the famous Huey).\n\n**What it requires:**\n- Owners must inspect the **tail rotor blade grips** — the metal components that hold the tail rotor blades in place — on affected helicopters.\n- The inspection checks whether the metal has become too soft (below 70 on the Rockwell hardness scale) or has improper electrical conductivity (below 29 on the copper standard).\n- These checks must be done using specific testing equipment: either a Rockwell Hardness Tester or an Eddy Current Tester (model FM120 or equivalent).\n\n**Who must comply:**\n- Anyone operating a Bell 205 helicopter with specific tail rotor hub part numbers (ending in -5, -7, -11, -13, or -19).\n\n**When it had to be done:**\n- For blade grips already installed on helicopters: **before flying again after 3 March 1970**.\n- For spare blade grips sitting in inventory: **before installing them on any aircraft after 3 March 1970**.\n\n**Why it matters:**\nSoft or improperly hardened metal in tail rotor components can lead to catastrophic failure. The tail rotor keeps the helicopter from spinning uncontrollably — if it fails, the aircraft crashes. This directive prevents that by catching defective parts before they fail in flight."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD as presented targets a clearly defined set of parts on the Bell 205 series and prescribes specific measurement criteria, test locations, acceptable equipment, and compliance timings. There is no indication within the supplied text that the scope differs from that technical focus or that it was broadened or narrowed from an original intent; the instrument confines itself to inspections of the listed P/N blade grips. (Applicability, Requirement, Note, Compliance)"},"complexity_factors":["Narrow applicability to specific aircraft model and listed part numbers (straightforward scope). (Applicability)","Technical measurement thresholds and specified measurement location (hardness 70 Rockwell B or conductivity <=29 at serial-number-adjacent spot). (Requirement)","Specified acceptable test equipment with allowance for 'equivalent' devices (requires equipment calibration and judgement about equivalence). (Note)","Urgent compliance timing for installed parts (before further flight) and pre-installation requirement for spares (creates operational scheduling pressure). (Compliance)","Practical needs for trained personnel and access to the specific test site on the part (practical implementation detail). (Requirement, Note)"],"plain_english_summary":"What this instrument does (mechanics)\n\n- It requires specific inspections of tail rotor blade grip assemblies on Bell Helicopter Textron 205 series helicopters that are fitted with any of the listed part numbers (P/N 204-011-801-5 or -7, or P/N 204-011-701-11, -13 or -19). (Applicability)\n- The inspection must measure either: a minimum hardness of 70 on the Rockwell B scale, or a conductivity of 29 or lower on the international annealed copper standard. Readings are to be taken adjacent to the vibro‑etched serial number between the blade retention bolts on the grip face. (Requirement)\n- The tests may be done using a Rockwell Harness Tester or an Eddy Current Tester such as the Magnatest FM120, or an equivalent device. (Note)\n- For blade grips already installed on an aircraft, the inspection must be done before further flight after 3 March 1970. For spare blade grips, the inspection must be done before they are installed on an aircraft after 3 March 1970. (Compliance)\n\nOfficial purpose-claim and how the instrument implements it\n\n- The document is an Airworthiness Directive, i.e. a regulatory requirement presented to address an airworthiness matter for the listed helicopters (header and Schedule of Airworthiness Directives). Mechanically, it implements that aim by mandating an immediate, instrumented test of a defined physical property (hardness or conductivity) at a specified location on the part, and by setting strict timing for compliance. (Applicability, Requirement, Compliance)\n\nCosts, incentives, trade-offs and implementation mechanics\n\n- Who pays: aircraft owners/operators must ensure the tests are performed and pay for them (Compliance). If an operator lacks the permitted test equipment, they will need to contract a maintenance organisation that has the equipment. (Requirement, Note)\n- Compliance burden and timing: inspections on installed parts must be completed before further flight (urgent, see Compliance), which creates immediate downtime and scheduling pressure. Spares must be inspected before installation, which adds a step to inventory management and pre‑installation checks. (Compliance)\n- Equipment and personnel: the AD specifies acceptable test methods and equipment (Rockwell Harness Tester or Eddy Current Tester Magnatest FM120 or equivalent). Operators or maintenance providers must therefore have access to suitably calibrated testers and personnel able to take readings at the specified spot on the grip face. Measurement technique and access to the specified test location (adjacent to the vibro‑etched serial number, between blade retention bolts) are part of the compliance task. (Requirement, Note)\n- Effects on businesses and market interactions: independent maintenance organisations that already possess the specified testers can offer inspection services; operators without such capability will incur outsourcing costs. The requirement can shift marginal work and revenue to authorised or equipped MROs. Spare‑part suppliers and inventory managers must ensure spares are inspected before installation, which can change logistics and lead times. (Applicability, Requirement, Compliance)\n- Enforcement and discretion: the AD sets a mandatory technical standard and timing for compliance. The text specifies the measurements, locations, and acceptable test equipment, leaving limited technical discretion to the maintainer beyond choosing an equivalent tester where appropriate. (Requirement, Note)\n\nImplementation risks and practical trade-offs\n\n- Measurement accuracy and equivalence: the AD permits “equivalent” testers but requires readings at a small, defined location; differences in tester calibration, operator technique, or accessibility to the test point can affect outcomes and may require repeat testing or part rejection. (Requirement, Note)\n- Supply and replacement effects: if grips fail the test, operators must remove and replace them, which could increase demand for serviceable spares and affect part availability and operating costs. The AD does not specify replacement criteria or follow‑up procedures beyond the inspection mandate. (Requirement, Compliance)\n\nNet operational effect (mechanical summary)\n\n- Owners/operators of affected Bell 205 helicopters must verify that certain tail rotor blade grips meet specific hardness or conductivity thresholds at a specified location using specified or equivalent test equipment, and must do so either immediately for installed parts (before further flight) or before installing spares. The obligation shifts testing costs and logistical burden to operators and maintenance providers, while specifying a narrow technical compliance pathway. (Applicability, Requirement, Note, Compliance)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-205-7-tail-rotor-blade-grip-inspection","history":"/api/acts/ad-bell-205-7-tail-rotor-blade-grip-inspection/history","analysis":"/api/acts/ad-bell-205-7-tail-rotor-blade-grip-inspection/analysis","conflicts":"/api/acts/ad-bell-205-7-tail-rotor-blade-grip-inspection/conflicts","importantCases":"/api/acts/ad-bell-205-7-tail-rotor-blade-grip-inspection/important-cases","documents":"/api/acts/ad-bell-205-7-tail-rotor-blade-grip-inspection/documents"}}