{"id":"F2006B03643","name":"AD/BEECH 1900/26 - MLG Actuator End Cap","slug":"ad-beech-1900-26-mlg-actuator-end-cap","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43233,"registerId":"commonwealth-F2006B03643-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 1900/26 - MLG Actuator End Cap","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)  \nBeechcraft 1900 Series Aeroplanes\n\nAD/BEECH 1900/26 MLG Actuator End Cap 4/99\n\nApplicability: Model Serial Numbers\n\n1900 UA-2 and UA-3\n\n1900C UB-1 through UB-74, and UC-1 through UC-174\n\n1900C (C-12J) UD-1 through UD-6\n\n1900D UE-1 through UE-299\n\nRequirement: Inspect the main landing gear hydraulic actuators to determine whether any Frisby Aerospace actuator, part number (P/N) 114-380041-11 or P/N 114-380041-13 is installed. Accomplish this inspection in accordance with Raytheon Mandatory Service Bulletin (MSB) SB.32-3141.\n\nIf any Frisby Aerospace actuator, P/N 114-380041-11 or P/N 114-380041-13 is installed, before further flight, remove it and accomplish one of the following:\n\n    Replace the Frisby Aerospace actuator with one of a part number listed in the Material Information section of Raytheon MSB SB.32-3141. Accomplish this replacement in accordance with the applicable maintenance manual; or,\n\n    2. Rework the Frisby Aerospace actuator by incorporating the kit referenced in the Material Information section of Raytheon MSB SB.32-3141. Accomplish this rework in accordance with Frisby Aerospace Service Bulletin 1FA10043-0001, dated October 1997.\n\nNote: FAA AD 99-04-08 Amdt 39-11032 refers.\n\nCompliance: Hours Time-in-Service (TIS) on the\n\nMLG Actuator\n\n  \nInspection Compliance Times after 22 April 1999\n\nLess than 6,000 hours TIS Upon accumulating 6,600 hours TIS on the actuator or within the next 600 hours TIS, whichever occurs later\n\n6,000 hours TIS through 6,999 hours TIS Within the next 600 hours TIS 7,000 hours TIS through 7,999 hours TIS Within the next 500 hours TIS 8,000 hours TIS through 8,999 hours TIS Within the next 400 hours TIS 9,000 hours TIS through 9,999 hours TIS Within the next 300 hours TIS 10,000 hours TIS or more Within the next 200 hours TIS This Airworthiness Directive becomes effective on 22 April 1999.\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nBackground: The FAA received reports of fatigue cracks in the end cap of main landing gear hydraulic actuators manufactured by Frisby Aerospace and installed on the affected aircraft. The actions specified by this Directive are intended to prevent the main landing gear from failing to lock down due to the hydraulic actuator cracking and separating, which could result in loss of control of the aircraft during landing, taxi, or ground operations.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD remains narrowly focused on the original technical problem: fatigue cracking in the end cap of certain Frisby Aerospace MLG hydraulic actuators fitted to specified Beechcraft 1900 aircraft. It does not broaden the regulated subject matter beyond inspection and corrective action for those actuators; it prescribes timing, identification, and two specific remedial paths (replacement or rework). Therefore the scope has not grown beyond the original safety-remediation purpose described in the Background."},"complexity_factors":["Applicability split across multiple model/serial-number ranges (several blocks listed)","Two specific Frisby actuator part numbers trigger the requirement (P/N 114-380041-11 and P/N 114-380041-13)","Two alternative corrective actions: replacement with approved P/Ns or rework with Frisby kit","Cross-references to external documents: Raytheon MSB SB.32-3141 and Frisby Service Bulletin 1FA10043-0001","Compliance schedule structured as multiple TIS bands with different inspection windows (nested timing conditions)","Dependence on Material Information section of Raytheon MSB for approved replacement part numbers","Reference to FAA AD creates an external regulatory cross-link"],"plain_english_summary":"**What this instrument does (mechanical change)**\n\n- Requires operators of specific Beechcraft 1900 series aeroplanes (listed by model and serial number in the AD) to inspect the main landing gear (MLG) hydraulic actuators to see whether a Frisby Aerospace actuator with part number 114-380041-11 or 114-380041-13 is installed. (Applicability / Requirement)\n- If one of those Frisby actuators is fitted, the aeroplane must not fly again until the actuator is either:\n  - Replaced with an approved actuator part number listed in the Raytheon Mandatory Service Bulletin (MSB SB.32-3141), following the applicable maintenance manual; or\n  - Reworked by installing the Frisby rework kit identified in Raytheon MSB SB.32-3141, carried out in accordance with Frisby Aerospace Service Bulletin 1FA10043-0001 (dated October 1997). (Requirement)\n- Sets mandatory inspection timing based on the actuator’s accumulated hours-in-service (TIS). The AD gives stepwise windows (for example, less than 6,000 hours: inspect on reaching 6,600 hours or within the next 600 hours whichever is later; 6,000–6,999: within 600 hours; 7,000–7,999: within 500 hours; and so on up to 10,000+ hours: within 200 hours). The AD became effective on 22 April 1999. (Compliance)\n\n**Who this affects**\n\n- Aircraft owners/operators of the specified Beechcraft 1900 series aircraft (the serial number ranges listed under Applicability).\n- Maintenance organisations and engineers who perform the inspections, replacements and rework.\n- Parts suppliers and manufacturers (Frisby Aerospace, Raytheon, and any suppliers of the approved replacement P/Ns) who may supply replacement actuators or rework kits.\n\n**Why it matters (official rationale and what that implies mechanically)**\n\n- The AD is prompted by reports of fatigue cracks in the end cap of Frisby Aerospace MLG hydraulic actuators. The stated safety purpose is to prevent the actuator cracking and separating, which could stop the landing gear from locking down and lead to loss of control during landing, taxi or ground operations. (Background)\n- Mechanically, the AD forces identification and removal or repair of a specific potentially-failing component type before further flights — removing the risk by substitution (approved replacement parts) or modification (rework kit). (Requirement)\n\n**Costs, incentives and trade-offs (practical effects)**\n\n- Who pays: the aircraft owner/operator pays inspection labour, the cost of replacement actuators or rework kits, and aircraft downtime. (Requirement / Material Information references)\n- Incentives: operators will choose whichever option minimises total cost and downtime — direct purchase of replacement actuators or rework of existing units — subject to parts availability and labour capacity. Parts suppliers for approved replacement P/Ns and Frisby (rework kit) gain demand. Maintenance organisations gain billable work.\n- Trade-offs: immediate safety risk mitigation versus the direct monetary cost and aircraft out-of-service time. Operators with many affected aircraft face concentrated, predictable maintenance bills; operators with few aircraft face smaller but fixed-per-aircraft compliance costs.\n- Opportunity cost: time and funds spent complying are not available for other maintenance or investments.\n\n**Implementation and compliance risks**\n\n- The AD relies on correct identification of actuator part numbers during inspection and correct incorporation of steps from external documents (Raytheon MSB SB.32-3141 and Frisby SB 1FA10043-0001). These cross-references create a dependency on the availability and clarity of those service bulletins. (Requirement)\n- If replacement parts or rework kits are in short supply, operators may face longer grounding/downtime or have to source acceptable alternatives through approved maintenance procedures.\n- The AD mandates removal before further flight if an affected actuator is found, producing immediate operational disruption for non-compliant aircraft.\n\n**Effects on markets and private enterprise**\n\n- Demand shifts to suppliers of the approved replacement actuators listed in Raytheon MSB SB.32-3141 and to Frisby for rework kits. This can concentrate sales among a small set of manufacturers or approved parts lists.\n- Maintenance providers capture work to carry out inspections, replacements and reworks; firms with authorisations and stock/skill for the specific actuators have a competitive advantage.\n- The AD constrains contract freedom in practice (operators must follow the replacement or rework options prescribed), but it does not specify a single supplier: it references manufacturer-approved replacement P/Ns and a rework kit as allowed remedies. (Requirement)\n\n**Other practical notes**\n\n- The AD cross-references an FAA Airworthiness Directive (FAA AD 99-04-08); operators and maintainers commonly use such cross-references to find technical instructions and part lists. (Note)\n- The AD’s compliance windows are explicitly tied to actuator hours-in-service rather than calendar time; this targets higher-risk components sooner but requires reliable recordkeeping of actuator TIS. (Compliance)\n\n"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope: addressing a specific mechanical defect in specific aircraft models. It has not expanded beyond its original safety purpose of preventing main landing gear actuator failures."},"complexity_factors":["Single, clearly defined applicability (specific aircraft models and serial numbers)","Straightforward binary requirement: inspect → if found, replace or repair","Tiered compliance schedule based on hours of use (6 distinct time bands)","References to external technical documents (Raytheon MSB SB.32-3141 and Frisby Aerospace Service Bulletin) without reproducing their content","No nested exceptions or conditional logic beyond the initial inspection trigger","Limited defined terms (only 'TIS' for Time-in-Service is used as shorthand)"],"plain_english_summary":"This mandatory Australian safety order requires operators of Beechcraft 1900/1900C/1900D aircraft with Frisby actuator part numbers 114-380041-11 or -13 to inspect for fatigue cracks in main landing-gear actuator end caps and, if found, replace or repair them with an approved kit before further flight. Deadlines vary by actuator time‑in‑service, with the shortest compliance windows for the highest hours. Non‑compliance grounds the aircraft."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-1900-26-mlg-actuator-end-cap","history":"/api/acts/ad-beech-1900-26-mlg-actuator-end-cap/history","analysis":"/api/acts/ad-beech-1900-26-mlg-actuator-end-cap/analysis","conflicts":"/api/acts/ad-beech-1900-26-mlg-actuator-end-cap/conflicts","importantCases":"/api/acts/ad-beech-1900-26-mlg-actuator-end-cap/important-cases","documents":"/api/acts/ad-beech-1900-26-mlg-actuator-end-cap/documents"}}