{"id":"F2006B02042","name":"AD/AA-5/10 Amdt 1 - Carburettor Mixture Control - Modification","slug":"ad-aa-5-10-amdt-1-carburettor-mixture-control-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41264,"registerId":"commonwealth-F2006B02042-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AA-5/10 Amdt 1 - Carburettor Mixture Control - Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-description: CASA Airworthiness Directive\nmeta-generator: Aspose.Words for .NET 22.10.0\nmeta-keywords: Issue NK,Aircraft below 5700 kg,Gulfstream (Grumman American/ American Aviation) AA-5 Series Aeroplanes,Carburettor Mixture Control - Modification,10 Amdt 1\ntitle: Airworthiness Directive - AD/AA-5/10 Amdt 1 - Carburettor Mixture Control - Modification\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)  Gulfstream (Grumman American/ American Aviation) AA-5 Series Aeroplanes\n\n \n\nAD/AA-5/10\n\nAmdt 1\n\n\nCarburettor Mixture Control - Modification NK\n\n \n\nApplicability: Model AA5B with S/Nos. AA5B-0001 to AA5B-0215. Document:  Grumman American Aviation SB No. 150A. Compliance:               Within 100 hours’ time in service after 10 February 1976.\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":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The supplied extract specifies applicability (Model AA5B, S/N AA5B-0001 to AA5B-0215), the technical reference (SB No. 150A) and a compliance interval (within 100 hours’ time in service after 10 February 1976). The text does not contain information about any prior or alternative scope, so there is no evidence in this document that the scope has been changed from an earlier version. Without the earlier version of the directive, a change cannot be demonstrated from the provided material."},"complexity_factors":["Narrow, specific applicability limited to Model AA5B serial numbers AA5B-0001 to AA5B-0215 (Applicability).","Technical work is delegated to an external document (Grumman American Aviation SB No. 150A), so the AD is short but relies on another source for procedural detail (Document).","A fixed compliance window (within 100 hours' time in service after 10 February 1976) creates a clear but time-bound enforcement requirement (Compliance).","The supplied text omits explanatory material (no explicit rationale, cost estimates, or enforcement details), limiting interpretive complexity but increasing practical reliance on the service bulletin and regulator practice (Header/authority; Document)."],"plain_english_summary":"### What this directive does\n\n- This Airworthiness Directive (AD) requires a modification to the carburettor mixture control on certain Gulfstream (Grumman American/American Aviation) AA-5 series aeroplanes. The technical instructions for the modification are contained in Grumman American Aviation Service Bulletin No. 150A (Document: Grumman American Aviation SB No. 150A). (Document)\n\n- The rule applies only to Model AA5B aeroplanes with serial numbers AA5B-0001 through AA5B-0215. (Applicability)\n\n- The modification had to be carried out within 100 hours’ time in service after 10 February 1976. (Compliance)\n\n### Who it affects\n\n- Owners and operators of the AA5B aeroplanes listed by serial number. They are the parties responsible for arranging and paying for the modification. (Applicability; Compliance)\n\n- Maintenance organisations and technicians who must carry out the work according to the referenced service bulletin. (Document)\n\n### Why it matters (official claim and what the text shows)\n\n- The AD is issued under the Commonwealth Civil Aviation framework (Part 39) and appears in the Schedule of Airworthiness Directives, which is the mechanism regulators use to mandate corrective actions for identified aircraft issues. The AD text supplied does not state an explicit safety rationale or describe the underlying defect or incident prompting the change. The directive therefore prescribes a mandatory corrective action but does not include the regulator’s explanatory detail in this extract. (Header/authority)\n\n### Practical mechanics, incentives and trade-offs\n\n- Who pays: aircraft owners/operators must fund the modification and any associated aircraft downtime. The AD sets the legal obligation to comply. (Applicability; Compliance)\n\n- Who decides how it is done: the AD points to Service Bulletin No. 150A for the technical method; that document governs the specific work to be performed. The AD itself does not set technical detail beyond the reference. (Document)\n\n- Compliance burden: owners/operators had to schedule the modification within the specified 100 hours’ time-in-service window from the 10 February 1976 date. That creates a scheduling and maintenance burden proportional to aircraft utilisation. (Compliance)\n\n- Enforcement and discretion: the AD imposes a mandatory requirement under the Civil Aviation Regulations (Part 39) framework, but the supplied text does not describe enforcement mechanisms, exemptions, or variations. The AD delegates technical implementation to the service bulletin, which gives maintenance providers the procedural discretion to follow the specified steps. (Header/authority; Document)\n\n- Potential effects on market participants: the requirement creates demand for maintenance work from owners/operators of the affected serial-numbered aircraft and therefore provides work for qualified maintenance organisations. The AD does not specify funding or compensation, so the financial cost is borne by the aircraft owners/operators. (Applicability; Document; Compliance)\n\n### Limits of what can be concluded from this text\n\n- The document supplied is brief and factual. It identifies the affected fleet, prescribes a modification, cites the service bulletin that contains the technical steps, and sets a compliance deadline. It does not include the regulator’s stated safety justification, cost estimates, enforcement approach, or any discussion of alternatives. Because those items are not present in the supplied text, they cannot be affirmed or tested further here."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive targeting a specific technical defect in a specific aircraft model range. It has not expanded beyond its original safety purpose."},"complexity_factors":["Extremely short document (approximately 150 words)","Only 1 defined applicability criterion (specific serial number range)","Single compliance requirement with clear deadline","No cross-references to other legislation beyond basic enabling regulation (CAR 1998 Part 39)","No conditional logic, exceptions, or nested provisions","Straightforward command structure: 'applies to X, do Y by Z date'"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). Think of it like a compulsory recall notice for aircraft, but with legal force.\n\n**What it requires:** Owners and operators of specific **Gulfstream AA-5B aeroplanes** (serial numbers AA5B-0001 through AA5B-0215) must modify the **carburettor mixture control** — the mechanism that adjusts the fuel-air mix going into the engine. This modification must be done according to **Grumman American Aviation Service Bulletin No. 150A** (a technical instruction manual from the manufacturer).\n\n**Who must comply:** Anyone operating these specific aircraft models in Australia.\n\n**When:** The work must be completed **within 100 hours of flight time** after 10 February 1976.\n\n**Why it matters:** Carburettor mixture controls are critical for engine performance and safety. A faulty or poorly designed control could cause engine failure, rough running, or dangerous fuel mixtures — potentially leading to accidents. This AD ensures a known safety defect gets fixed across the affected fleet."}},"importantCases":[],"_links":{"self":"/api/acts/ad-aa-5-10-amdt-1-carburettor-mixture-control-modification","history":"/api/acts/ad-aa-5-10-amdt-1-carburettor-mixture-control-modification/history","analysis":"/api/acts/ad-aa-5-10-amdt-1-carburettor-mixture-control-modification/analysis","conflicts":"/api/acts/ad-aa-5-10-amdt-1-carburettor-mixture-control-modification/conflicts","importantCases":"/api/acts/ad-aa-5-10-amdt-1-carburettor-mixture-control-modification/important-cases","documents":"/api/acts/ad-aa-5-10-amdt-1-carburettor-mixture-control-modification/documents"}}