{"id":"F2006L03498","name":"AD/B737/296 - Auxiliary Fuel System","slug":"ad-b737-296-auxiliary-fuel-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":61020,"registerId":"commonwealth-F2006L03498-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 737 Series Aeroplanes","sectionType":"division","heading":"Boeing 737 Series Aeroplanes","content":"### Boeing 737 Series Aeroplanes\n\n| AD/B737/296 | Auxiliary Fuel System | 12/2006 |\n| ----------- | --------------------- | ------- |\n\n```html\n

Applicability:

Boeing Model 737-200, -300, -400, and -500 series aeroplanes equipped with an auxiliary fuel system installed in accordance with FAA Approved Supplemental Type Certificate (STC) SA83NE, SA1078NE, SA725NE, ST00040NY, or ST01337NY; having serial numbers (S/N) listed in Table 1 of this AD.

Table 1 - Applicability

For Model -

Having S/N(s) -

As identified in PATS
Aircraft Service Bulletin -

737-200 series airplanes

22431 and 22628

SA83NE-28-SB-002_IR,
dated 7 June 7 2006

737-200 series airplanes

22600

SA1078NE-28-SB-005_A, Revision A, dated 21 June 2006

737-200, -300,
-400, and -500 series airplanes

23800, 22620, 23124, 23468, 26333, 26307, 27456, 27426, and 27906

SA725NE-28-SB-007_B, Revision B, dated 27 July 2006

737-500 series airplanes

24970

ST00040NY-28-SB-003_IR, dated 7 June 2006

737-500 series airplanes

28866

ST01337NY-28-SB-002_IR, dated 7 June 2006

Requirement:

Action in accordance with FAA AD 2006-18-11 Amendment 39-14750.

Compliance:

As detailed in FAA AD 2006-18-11 with a revised effective date of
23 November 2006.

This Airworthiness Directive becomes effective on 23 November 2006.

Background:

This AD results from a re-evaluation of the floor structure and cargo barriers conducted by the STC holder. The actions detailed in this AD are intended to prevent structural overload of the auxiliary fuel tank support structure, which could cause the floor beams to fail and resultant damage to the primary flight controls and the auxiliary power unit fuel lines that pass through the floor beams, and consequent loss of control of the aeroplane.

\n```\n\n| | These actions are also intended to prevent structural overload of the cargo barriers, which could cause the barriers to fail, allowing the cargo to shift, resulting in possible damage to the auxiliary fuel tanks, residual fuel leakage, and consequent increased risk of a fire. |\n| --- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n\n![](image.001.png) \nJames Coyne \nDelegate of the Civil Aviation Safety Authority\n\n12 October 2006","sortOrder":0},{"sectionNumber":"AD/B737/296","sectionType":"part","heading":"AD/B737/296","content":"## AD/B737/296","sortOrder":1},{"sectionNumber":"Auxiliary Fuel System","sectionType":"part","heading":"Auxiliary Fuel System","content":"## Auxiliary Fuel System","sortOrder":2},{"sectionNumber":"12/2006","sectionType":"part","heading":"12/2006","content":"## 12/2006","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The directive adopts and enforces the scope of FAA AD 2006-18-11 for the listed STC-equipped 737 serial numbers. It does not broaden applicability beyond the aircraft, STCs and service-bulletins identified; it implements corrective actions arising from the STC holder's re-evaluation of floor structure and cargo barriers as described in the Background."},"complexity_factors":["Narrow applicability: limited to specific Boeing 737 models and serial numbers listed in Table 1 (affects only identified aircraft).","Cross-reference dependency: mandates compliance by reference to FAA AD 2006-18-11 and multiple STC-specific service bulletins, increasing procedural complexity for implementers.","Technical remedies: requires inspection/modification of structural supports, cargo barriers and fuel-system components — work that needs certified maintenance resources and possible parts.","Operational impact: compliance imposes direct costs, maintenance time and potential downtime on aircraft owners/operators.","Enforcement and documentation: CASA enforcement of an externally authored (FAA) AD requires record-keeping to show adherence to the referenced documents."],"plain_english_summary":"This Airworthiness Directive compels owners/operators of specific Boeing 737-200/300/400/500 aeroplanes fitted with STC-installed auxiliary fuel systems (listed by serial number) to perform the inspections and corrective actions set out in FAA AD 2006‑18‑11 (effective 23 Nov 2006). Mechanically it requires carrying out the referenced service-bulletin actions to inspect/modify auxiliary fuel-tank supports and cargo barriers.\n\nCASA enforces compliance; owners/operators bear the cost and operational downtime. The AD’s stated aim is to prevent structural overload that could damage flight controls or fuel lines, cause fuel leakage, or increase fire risk."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope. It targets a specific safety issue identified by the STC holder regarding auxiliary fuel tank support structures on a limited fleet of modified Boeing 737 aircraft. The document does not represent scope creep; rather, it precisely targets the identified unsafe condition without expanding to unrelated systems or aircraft types."},"complexity_factors":["Extensive cross-referencing to external FAA documentation (FAA AD 2006-18-11) without reproducing those requirements in full","Highly specific applicability criteria combining: aircraft model series, specific STC numbers (5 different certificates), and individual serial numbers (11 specific aircraft)","Tabular data structure for applicability creates nested conditional logic (model + serial number + service bulletin reference)","Multiple service bulletin references with specific revision dates and numbers (6 different documents)","Technical aviation terminology requiring domain knowledge (STC, floor beams, auxiliary power unit, primary flight controls)","Incorporation by reference of US regulatory requirements creates jurisdictional complexity"],"plain_english_summary":"This CASA Airworthiness Directive mandates owners/operators of specific Boeing 737-200/300/400/500 aircraft fitted with certain STC auxiliary fuel systems (about 11 serial-numbered planes) to carry out the inspections and corrective actions required by FAA AD 2006-18-11. \n\nIt addresses potential floor-beam and cargo-barrier failures that could damage flight controls or fuel lines, allow cargo/fuel-tank damage, or lead to loss of control and fire."},"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-b737-296-auxiliary-fuel-system","history":"/api/acts/ad-b737-296-auxiliary-fuel-system/history","analysis":"/api/acts/ad-b737-296-auxiliary-fuel-system/analysis","conflicts":"/api/acts/ad-b737-296-auxiliary-fuel-system/conflicts","importantCases":"/api/acts/ad-b737-296-auxiliary-fuel-system/important-cases","documents":"/api/acts/ad-b737-296-auxiliary-fuel-system/documents"}}