{"id":"F2006B06078","name":"AD/PC-12/15 - Flap Actuator - Life Limitation","slug":"ad-pc-12-15-flap-actuator-life-limitation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114476,"registerId":"commonwealth-F2006B06078-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PC-12/15 - Flap Actuator - Life Limitation","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)  \nPilatus PC-12 Series Aeroplanes\n\nAD/PC-12/15 Flap Actuator \\- Life Limitation 4/99\n\nApplicability: Model PC12 and PC12/45 aircraft.\n\nRequirement: 1a. Perform a one time inspection to determine the serial number of the installed flap screw actuators in accordance with Para 3A of Pilatus PC-12 Service Bulletin No. 27-007 dated 26 January 1999.\n\n1b. Identify all the Limited Service Life flap screw actuators (identified by yellow bodies and serial number), record their in-service hours and landings in the aircraft log book and modify the System of Maintenance to reflect that the items are limited life and require a separate inspection/replacement programme.\n\nDetails of the limited life item inspection and replacement programme to be entered in the maintenance programme are given in the Aircraft Maintenance Manual Temporary Revisions 04-03 and 27-10 date 15 January 1999.\n\n2. Replace the limited life Flap Screw Actuators.\n\nNote: FOCA AD HB 99-142 dated 17 February 1999 refers.\n\nCompliance: 1. At the next scheduled Flap Screw Actuator inspection/Check (Backlash Check) or prior to fitment of a new item.\n\n    2. Whenever one of the following conditions occurs.\n\n    Flap system backlash limits exceed those given in the Aircraft Maintenance Manual, or\n\n    b. Life limited Flap Screw Actuators have accumulated a TIS of 500 hrs or 650 landings, whichever occurs first, or\n\n    c. No later than 30 September 1999.\n\nThis Airworthiness Directive becomes effective on 22 April 1999.\n\nBackground: Due to an acute shortage of standard flap actuators, a number of actuator units are being produced which incorporate a modified set of gears. These gears may exhibit premature wear. As a result, this Directive introduces a limited life policy for these actuator units and an inspection programme to remove them from service if early wear becomes apparent. The items should be all removed from service by September 1999.","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 Directive addresses a specific safety problem with modified flap screw actuators on PC‑12 series aeroplanes by imposing a limited‑life policy and inspection/replacement programme. It does not expand the affected aircraft types or introduce unrelated obligations. The change is a targeted operational limitation (limited‑life items and removal by 30 September 1999) directly aligned with the stated issue of premature gear wear (Background; Requirement)."},"complexity_factors":["Targeted applicability to specific models only (Model PC12 and PC12/45) — limits scope but requires model checks (Applicability).","Multiple and alternative compliance triggers: backlash exceedance, time-in-service (500 hrs) or landing-count (650 landings), or absolute calendar deadline (30 Sep 1999) (Compliance 2a–2c).","Dependence on external technical guidance: Pilatus Service Bulletin No. 27-007 para 3A and Aircraft Maintenance Manual Temporary Revisions 04-03 and 27-10 (Requirement 1a/1b).","Identification requirement relies on physical marking and serial numbers (yellow bodies and serial number) — introduces inspect-and-tag administrative step (Requirement 1b).","Administrative burden to record hours/landings in the aircraft logbook and amend the operator's System of Maintenance to include a separate inspection/replacement programme (Requirement 1b).","A one‑time inspection plus follow-up replacement programme — operational coordination needed to meet inspection scheduling (Compliance: inspection at next scheduled Backlash Check or before fitment).","Clear deadline and effective date (effective 22 April 1999; remove by 30 September 1999) compress implementation timeframes."],"plain_english_summary":"This Airworthiness Directive requires operators of Pilatus PC-12 and PC-12/45 aeroplanes to inspect flap screw actuators, identify limited‑life units (yellow bodies with serial numbers), record their in‑service hours and landings, update the maintenance program, and replace those actuators per Pilatus service and maintenance- manual revisions. Replacement is required if backlash limits are exceeded, when the unit reaches 500 flight hours or 650 landings (whichever first), or by 30 September 1999. Operators pay for inspection and replacement; maintenance organisations must implement the separate inspection/replacement programme."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope — addressing a specific temporary manufacturing defect in flap actuators for PC-12 aircraft. The directive's purpose (life-limiting substandard components and mandating their removal by a deadline) remains exactly as intended when issued. No scope creep is evident."},"complexity_factors":["Single, specific technical subject matter (flap actuators for one aircraft type)","Clear, numbered requirements with minimal conditional logic","Only 2 main compliance pathways (inspection/record-keeping vs replacement)","Three alternative compliance triggers presented as simple 'or' conditions","No defined terms section — all terminology is industry-standard aviation language","Short document (approximately 250 words)","Single cross-reference to foreign aviation authority document (FOCA AD HB 99-142) noted but not required for compliance","No nested exceptions or complex temporal calculations beyond a fixed date deadline"],"plain_english_summary":"This CASA Airworthiness Directive targets Pilatus PC-12 and PC12/45 aircraft that may have yellow-bodied, limited-life flap actuators with modified gears that wear prematurely. It requires operators to identify and log these actuators, track their usage separately in maintenance programs, and remove them before they reach their limited life or show excessive play.\n\nIt matters because worn actuators can cause flap malfunction during takeoff or landing, risking loss of control; the AD ensures these substandard parts are found and replaced."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pc-12-15-flap-actuator-life-limitation","history":"/api/acts/ad-pc-12-15-flap-actuator-life-limitation/history","analysis":"/api/acts/ad-pc-12-15-flap-actuator-life-limitation/analysis","conflicts":"/api/acts/ad-pc-12-15-flap-actuator-life-limitation/conflicts","importantCases":"/api/acts/ad-pc-12-15-flap-actuator-life-limitation/important-cases","documents":"/api/acts/ad-pc-12-15-flap-actuator-life-limitation/documents"}}