{"id":"F2005L03932","name":"AD/DO 328/28 - Airfoil De-ice Tube","slug":"ad-do-328-28-airfoil-de-ice-tube","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":39765,"registerId":"commonwealth-F2005L03932-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Dornier 328 Series Aeroplanes","sectionType":"division","heading":"Dornier 328 Series Aeroplanes","content":"### Dornier 328 Series Aeroplanes\n\n| AD/DO 328/28 | Airfoil De-ice Tube | 1/2006 |\n| ------------ | ------------------- | ------ |\n\n| Applicability: | Dornier 328-100 serial numbers 3042 through 3105 inclusive.                                                                                                                                                  |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement:   | Unless previously accomplished, replace the de-icing tube in accordance with Dornier 328 Service Bulletin No. SB-328-30-265 dated 24 July 1998 or later LBA approved revisions.Note: LBA AD 1998-423 refers. |\n| Compliance:    | Within 30 days after the effective date of this AD.                                                                                                                                                          |\n|                | This Airworthiness Directive becomes effective on 19 January 2006.                                                                                                                                           |\n| Background:    | A water trap in the de-ice tubing near the refuelling panel on the RH Wing, could cause a blockage if frozen, without warning to the pilot.                                                                  |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n30 November 2005","sortOrder":0},{"sectionNumber":"AD/DO 328/28","sectionType":"part","heading":"AD/DO 328/28","content":"## AD/DO 328/28","sortOrder":1},{"sectionNumber":"Airfoil De-ice Tube","sectionType":"part","heading":"Airfoil De-ice Tube","content":"## Airfoil De-ice Tube","sortOrder":2},{"sectionNumber":"1/2006","sectionType":"part","heading":"1/2006","content":"## 1/2006","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive addressing a specific safety defect in a specific aircraft type. It has not expanded beyond its original purpose of mandating a safety-critical component replacement."},"complexity_factors":["Single, specific mechanical requirement (replace one component)","Only one defined reference (the Service Bulletin)","Clear applicability limited to specific serial number range","Simple compliance deadline (30 days from effective date)","No nested conditions, exceptions, or alternative compliance methods","Background explanation is straightforward and single-issue focused"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order for aircraft. It applies to specific **Dornier 328-100 aeroplanes** (serial numbers 3042 to 3105).\n\n**What it does:**\n- Requires owners/operators to **replace a de-icing tube** on the right-hand wing\n- The replacement must follow a specific manufacturer's service bulletin (SB-328-30-265 from July 1998)\n\n**Why it matters:**\n- A **water trap** in the existing de-ice tubing could freeze and **block the tube without warning**\n- This could prevent the wing de-icing system from working properly, creating a **safety risk during flight in icing conditions**\n\n**When it must be done:**\n- Within **30 days** of 19 January 2006 (so by mid-February 2006)\n\n**Who issued it:**\n- **CASA** (Civil Aviation Safety Authority) — Australia's aviation safety regulator\n- Issued under delegation by James Coyne on 30 November 2005"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD remains narrowly focused on remedying a specific potential hazard (water trap/freeze blockage in the RH wing de-ice tubing) for a defined set of Dornier 328-100 serial numbers. It does not broaden the obligations beyond the original safety purpose: it prescribes a replacement action, points to the manufacturer's service bulletin for technical detail, and allows later LBA-approved revisions. There is no expansion into unrelated components, aircraft types, or ongoing monitoring requirements that would indicate a significant change of scope from the instrument's evident original intent."},"complexity_factors":["Very short, single-action directive: one mandatory corrective action (replace de-ice tube).","Single, short compliance window: within 30 days of the effective date.","Narrow applicability: specific serial numbers (3042–3105) — limited population reduces complexity.","Conditional phrase: 'Unless previously accomplished' requires record checks.","Dependency on external documents: requires following Dornier Service Bulletin SB-328-30-265 or later LBA-approved revisions (cross-reference increases administrative steps).","Reference to another authority's AD (LBA AD 1998-423) — adds an external cross-reference to verify context and earlier actions."],"plain_english_summary":"**What this directive does (mechanically)**\n\n- It orders owners/operators of certain Dornier 328-100 aeroplanes to replace a specific de-icing tube on the right-hand wing.\n- Applicability: Dornier 328-100 aircraft with serial numbers 3042 through 3105 inclusive (see \"Applicability\").\n- Required action: replace the de-ice tube in accordance with Dornier Service Bulletin SB-328-30-265 dated 24 July 1998, or a later revision approved by the LBA (German aviation authority).\n- Timing: the replacement must be done within 30 days after this Airworthiness Directive (AD) became effective, unless the replacement was already completed.\n\n**Why the change was made (stated reason)**\n\n- The AD says a water trap can form in the de-ice tubing near the refuelling panel on the right-hand wing. If that water freezes it could block the de-ice system unexpectedly, creating a safety risk for the flight crew (see \"Background\").\n\n**Who is affected and who pays**\n\n- Affected parties: the registered owners and operators of the specified serial-numbered Dornier 328-100 aircraft.\n- Costs fall on those owners/operators. They must arrange parts, maintenance labour, and aircraft downtime to complete the replacement within the 30-day window.\n\n**Who decides how to comply**\n\n- The AD requires compliance by following the specified Dornier service bulletin (SB-328-30-265) or a later revision if approved by the LBA. The regulator (Civil Aviation Safety Authority delegate who issued the AD) mandates compliance; the SB contains the technical steps and the LBA approves later revisions.\n\n**Practical effects and implementation notes**\n\n- Operators must inspect maintenance records to confirm whether the replacement has already been done; if not, they must schedule the work within 30 days.\n- The AD does not set out the detailed technical procedure itself; it relies on the service bulletin for the exact replacement method.\n- Potential implementation friction: availability of the replacement tube or maintenance slots may constrain some operators; those are practical costs and could require short-term scheduling or operational adjustments.\n\n**Costs, benefits, and trade-offs (mechanical, not value judgments)**\n\n- Direct costs: parts, labour, and aircraft out-of-service time for the affected fleet subset.\n- Concentration of burden: costs are concentrated on the relatively small group of operators who own the specified serial-number aircraft (serials 3042–3105).\n- Concentration of benefit: the safety benefit (reduced risk of a frozen blockage in the de-ice system) accrues primarily to those same operators and to flight crews and passengers on those aircraft.\n- Administrative discretion/oversight: the AD delegates technical detail to the manufacturer service bulletin and to later LBA-approved revisions; that gives the manufacturer and foreign regulator a role in defining compliance specifics.\n- Opportunity cost: maintenance resources allocated to this replacement are not available for other work during the compliance window.\n- Substitution effects: an operator could choose different scheduling (more downtime in one period) or use different approved repair facilities, but the technical action is mandated and must follow the SB/LBA-approved revision.\n\n**Cross-references and reliance on other instruments**\n\n- The AD cross-references Dornier service bulletin SB-328-30-265 (24 July 1998) and allows later LBA-approved revisions. A note also refers to LBA AD 1998-423. This means compliance requires consulting external documents and possibly foreign-authority approvals for later revisions.\n\n**Bottom line**\n\n- Mechanically the AD is a narrow, time-limited safety requirement: replace a potentially problematic de-ice tube on a defined set of Dornier 328-100 aircraft within 30 days, using a specified service bulletin or an LBA-approved later revision. The regulator sets the obligation; owners/operators pay for and arrange the work. The stated purpose is to remove the risk of an unannounced frozen blockage in the de-ice tubing (Background)."},"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-do-328-28-airfoil-de-ice-tube","history":"/api/acts/ad-do-328-28-airfoil-de-ice-tube/history","analysis":"/api/acts/ad-do-328-28-airfoil-de-ice-tube/analysis","conflicts":"/api/acts/ad-do-328-28-airfoil-de-ice-tube/conflicts","importantCases":"/api/acts/ad-do-328-28-airfoil-de-ice-tube/important-cases","documents":"/api/acts/ad-do-328-28-airfoil-de-ice-tube/documents"}}