{"id":"F2006B02679","name":"AD/B727/157 - Main Cargo Deck Floor Beams","slug":"ad-b727-157-main-cargo-deck-floor-beams","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41995,"registerId":"commonwealth-F2006B02679-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/157 - Main Cargo Deck Floor Beams","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)  \nBoeing 727 Series Aeroplanes\n\nAD/B727/157 Main Cargo Deck Floor Beams 3/99\n\nApplicability: Model 727 series aircraft that have been converted from a passenger to a cargo- carrying (“freighter”) configuration in accordance with Supplemental Type Certificate (STC) ST00015AT.\n\nRequirement: Action in accordance with the technical requirements of FAA AD 98-26-20 Amdt 39-10963.\n\nRevise the Limitations Sections of the Aircraft Flight Manual (AFM) and AFM Supplements to include the Flight Manual information specified in FAA AD 98-26-20 Amdt 39-10961. This task may be accomplished by inserting a copy of the FAA AD in the AFM and AFM Supplements.\n\nCompliance: As specified in the Requirement Document with a revised effective date of 25 March 1999.\n\nThis Airworthiness Directive becomes effective on 25 March 1999.\n\nBackground: The FAA has determined that under certain conditions unreinforced floor structure of the main cargo deck is not strong enough to enable the aircraft to safely carry the maximum payload that is currently allowed in this area. The actions specified by this Directive are intended to prevent failure of the floor structure, which could lead to loss of the aircraft.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow airworthiness directive targeting a specific structural issue in a specific aircraft modification. It remains tightly scoped to its original safety purpose with no evidence of scope creep."},"complexity_factors":["Very short document (under 300 words)","Only 1 defined term (STC ST00015AT, which is explained in plain language)","Single, clear requirement: follow the FAA directive","No nested exceptions or conditional logic — compliance is mandatory and straightforward","No cross-references to other Australian legislation beyond the enabling regulations (CAR 1998 Part 39)"],"plain_english_summary":"This safety order targets Boeing 727 freighters converted from passenger planes under STC ST00015AT. It mandates operators follow FAA AD 98-26-20 and update the Aircraft Flight Manual to add new weight/loading limits (compliance may be met by inserting the FAA directive into the AFM).\n\nWhy it matters: the main cargo floor can’t safely carry the current maximum loads; without action the floor could fail in flight. Affected operators must comply by 25 March 1999."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Yes. The directive changes the operational scope for affected aircraft by imposing new AFM limitations tied to FAA AD guidance, reducing or restricting payload/operations that were previously allowed for aircraft converted under STC ST00015AT (Applicability; Requirement; Background)."},"complexity_factors":["Narrow applicability — only Boeing 727s converted to freighters under STC ST00015AT (Applicability).","Regulatory cross‑reference — compliance requires following FAA AD 98‑26‑20 rather than a self‑contained CASA text (Requirement).","Administrative compliance — revising AFM and AFM supplements (Requirement) is straightforward but mandatory for each operator.","Fixed compliance date — effective 25 March 1999 creates a hard deadline for operators to act (Compliance).","Safety‑critical technical basis — directive responds to a structural strength shortfall in main cargo deck floor beams (Background), increasing urgency and enforcement attention.","Operational impact — imposes new AFM limitations that may reduce allowable payload or change loading practices (Background/Requirement)."],"plain_english_summary":"This AD requires operators of Boeing 727 aircraft converted to freighters under STC ST00015AT to revise the Aircraft Flight Manual and supplements to include specified FAA AD flight‑manual information (inserting a copy of the FAA AD is allowed). The FAA found that unreinforced main cargo‑deck floor beams may not safely support the currently allowed maximum payload; the AFM change limits operations to prevent floor failure. Operators bear the administrative task and any operational/payload limits; CASA enforces the directive from 25 March 1999."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-157-main-cargo-deck-floor-beams","history":"/api/acts/ad-b727-157-main-cargo-deck-floor-beams/history","analysis":"/api/acts/ad-b727-157-main-cargo-deck-floor-beams/analysis","conflicts":"/api/acts/ad-b727-157-main-cargo-deck-floor-beams/conflicts","importantCases":"/api/acts/ad-b727-157-main-cargo-deck-floor-beams/important-cases","documents":"/api/acts/ad-b727-157-main-cargo-deck-floor-beams/documents"}}