{"id":"F2015L00782","name":"AD/Robin/21 Amdt 3 - Stabilator Spar and Attachment Brackets","slug":"ad-robin-21-amdt-3-stabilator-spar-and-attachment-brackets","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":128586,"registerId":"commonwealth-F2015L00782-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Robin Aviation Series Aeroplanes","sectionType":"division","heading":"Robin Aviation Series Aeroplanes","content":"### Robin Aviation Series Aeroplanes\n\n| AD/ROBIN/21 Amdt 3 | Stabilator Spar and Attachment Brackets | 12/2015 |\n| ------------------ | --------------------------------------- | ------- |\n\n| Applicability: | This AD applies to all Model R2000 series aircraft.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |\n| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | For all aircraft, excluding aircraft with Major Mod 79 bulkhead reinforcement embodied:1. Visually inspect, with the aid of strong lighting, the forward face of the rear fuselage bulkhead, which supports the stabilator hinge brackets. Look for cracks and corrosion. Pay particular attention to the area outboard of the stabilator hinge bracket bolt holes and around the stabilator balance weight cutout.2. Remove the stabilator from the aircraft, in accordance with paragraph 4.4.1 of the Avions Pierre Robin R2000 Service Manual, then remove the stabilator hinge brackets from the rear fuselage bulkhead. Inspect the forward and aft faces of the bulkhead, outboard of the hinge bracket bolt holes and around the balance weight cutout, using the fluorescent dye penetrant method as detailed in Civil Aviation Order 108.10.Note: Alpha Aviation models R2160, R2160i & R2120U are manufactured with Major Mod 79 bulkhead reinforcement embodied.For all aircraft:3. Remove the stabilator from the aircraft, in accordance with paragraph 4.4.1 of the Avions Pierre Robin R2000 Service Manual, then remove the stabilator hinge brackets from the stabilator spar. Inspect around the bolt holes and nut plate rivets in the stabilator spar using the fluorescent dye penetrant method as detailed in Civil Aviation Order 108.10.            |\n| Compliance:    | 1. The action in Requirement 1 must be taken at the later of the following:(a) before 1 000 hours time in service; or(b) before further flight after 22 February 1995.Thereafter, a subsequent inspection is to occur at each interval of no more than 100 hours.2. The action in Requirement 2 must be taken at the later of the following:(a) before 2 000 hours time in service; or(b) before 25 hours time in service after 22 February 1995.Thereafter, a subsequent inspection is to occur at each interval of no more than 750 hours.3. The action in Requirement 3 must be taken at the later of the following:(a) before 2 000 hours time in service; or(b) before 25 hours time in service after 22 February 1995.Thereafter, a subsequent inspection is to occur at each interval of no more than 750 hours.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |\n|                | The effective date of this AD is 8 June 2015.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |\n| Background:    | During a precautionary inspection, not required by the maintenance schedule, a number of cracks were found in the rear fuselage bulkhead. Removal of the stabilator to facilitate repair revealed widespread cracking of the bulkhead and cracking of the stabilator spar near the hinge bracket bolts. The structural integrity of the stabilator attachment is critical to flight safety.Amendment 1 included repeat inspections of the stabilator spar. Laboratory examination of the cracked stabilator spar has indicated that the condition of the rear fuselage bulkhead cannot be used to gauge the condition of the stabilator spar. The fatigue cracks in the stabilator spar started from fretting damage due to free movement of the stabilator hinge fittings and the balance weight attachment fitting.Amendment 2 alleviated all R2000 aircraft with rear bulkhead strengthening modification (Major Mod 79) embodied, from the requirement for repetitive inspections to the forward face of the rear bulkhead structure.This Amendment 3 further alleviates those models with the Major Mod 79 fitted from the requirements to inspect the aft face of the bulkhead due to the modification covering the area of interest and the manufacturer advising they have not received any reports of cracking occurring to models with the modification installed. |\n\n![](image.001.png)\n\nMike Higgins  \nDelegate of the Civil Aviation Safety Authority\n\n1 June 2015","sortOrder":0},{"sectionNumber":"AD/ROBIN/21 Amdt 3","sectionType":"part","heading":"AD/ROBIN/21 Amdt 3","content":"## AD/ROBIN/21 Amdt 3","sortOrder":1},{"sectionNumber":"Stabilator Spar and Attachment Brackets","sectionType":"part","heading":"Stabilator Spar and Attachment Brackets","content":"## Stabilator Spar and Attachment Brackets","sortOrder":2},{"sectionNumber":"12/2015","sectionType":"part","heading":"12/2015","content":"## 12/2015","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":true,"description":"The original AD was issued to address cracking in the rear fuselage bulkhead and stabilator spar. Amendment 1 expanded scope to include repeat inspections of the stabilator spar as a separate requirement. Amendment 2 reduced scope by exempting Major Mod 79 aircraft from bulkhead inspections. Amendment 3 further narrows the scope by relieving Major Mod 79 aircraft from the aft face bulkhead inspection requirement. The legislation has evolved from a blanket inspection mandate to a more targeted, risk-based approach that differentiates between modified and unmodified aircraft."},"complexity_factors":["Multiple conditional applicability rules (exclusions for Major Mod 79 vary by requirement)","Nested timing requirements with 'later of' clauses combining flight hours and calendar dates","Cross-reference to external technical document (Civil Aviation Order 108.10 for inspection methods)","Cross-reference to manufacturer service manual (Avions Pierre Robin R2000 Service Manual, paragraph 4.4.1)","Three distinct compliance schedules with different intervals (100 hours vs 750 hours)","Technical aviation terminology requiring domain knowledge (stabilator, bulkhead, dye penetrant, time in service)","Amendment history references (Amendments 1, 2, and 3) creating contextual dependencies"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of Robin R2000-series aircraft to perform mandatory inspections of the tail structure—focused on the rear fuselage bulkhead and stabilator spar/hinges—to detect fatigue cracks that could cause loss of pitch control. It affects all R2000s (with certain Alpha Aviation variants noted) and sets repetitive inspection intervals. Amendment 3 relieves aircraft with Major Mod 79 from inspecting the bulkhead’s aft face."},"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":true,"description":"Amendment 3 narrows the AD's scope vis-à-vis the original directive by further relieving aircraft fitted with Major Mod 79 bulkhead reinforcement from the requirement to inspect the aft face of the rear bulkhead. Earlier Amendment 2 had already exempted Mod 79 aircraft from repetitive inspections of the forward face; Amendment 3 removes the aft-face inspection because the modification ‘covers the area of interest’ and the manufacturer reported no cracking for modified models (Background; Requirements)."},"complexity_factors":["Multiple distinct inspection tasks with different scopes (visual forward-face check; removal and dye-penetrant inspections of bulkhead and stabilator spar) (Requirement 1–3).","Different initial compliance triggers and repeat intervals for each requirement (e.g. 1,000 h then 100 h repeats; 2,000 h then 750 h repeats) increasing scheduling complexity (Compliance).","Conditional exemptions for aircraft with Major Mod 79 reinforcement, and a specific narrowing of that exemption in Amendment 3 (Requirements; Background).","Mandatory removal of the stabilator and reference to a service manual procedure (Avions Pierre Robin R2000 Service Manual para 4.4.1) increasing hands-on labour and downtime (Requirement 2–3).","Use of a specialised non-destructive test method (fluorescent dye penetrant) tied to Civil Aviation Order 108.10, requiring certified technique/equipment (Requirement 2–3).","Layered amendment history (original AD, Amendment 1, Amendment 2, Amendment 3) creates interpretive risk about which inspections remain mandatory for particular airframes (Background).","Operational impact concentrated on aircraft owners/operators and maintenance organisations (costs, parts, downtime), while regulatory discretion is limited to prescribing intervals and acceptable methods as stated."],"plain_english_summary":"This airworthiness directive requires owners/operators of Robin R2000-series aeroplanes to perform visual and fluorescent dye‑penetrant inspections of the rear fuselage bulkhead and the stabilator spar/hinge brackets, including removal of the stabilator for some checks. It sets initial compliance hours and recurring inspection intervals, and excludes aircraft with Major Mod 79 bulkhead reinforcement from specified bulkhead inspections.\n\nThe AD says cracks were found; Amendment 3 removes the aft‑bulkhead inspection for Mod 79 aircraft because the modification covers the area. Owners pay inspection labour and downtime, the regulator prescribes intervals, and maintenance choices (repeat inspections, parts replacement) determine safety and cost trade‑offs."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-robin-21-amdt-3-stabilator-spar-and-attachment-brackets","history":"/api/acts/ad-robin-21-amdt-3-stabilator-spar-and-attachment-brackets/history","analysis":"/api/acts/ad-robin-21-amdt-3-stabilator-spar-and-attachment-brackets/analysis","conflicts":"/api/acts/ad-robin-21-amdt-3-stabilator-spar-and-attachment-brackets/conflicts","importantCases":"/api/acts/ad-robin-21-amdt-3-stabilator-spar-and-attachment-brackets/important-cases","documents":"/api/acts/ad-robin-21-amdt-3-stabilator-spar-and-attachment-brackets/documents"}}