{"id":"F2006L02234","name":"AD/BAe 146/122 - Nose Landing Gear Axle Spacer","slug":"ad-bae-146-122-nose-landing-gear-axle-spacer","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":117560,"registerId":"commonwealth-F2006L02234-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"British Aerospace BAe 146 Series Aeropla","sectionType":"division","heading":"British Aerospace BAe 146 Series Aeroplanes","content":"### British Aerospace BAe 146 Series Aeroplanes\n\n| AD/BAe 146/122 | Nose Landing Gear Axle Spacer | 8/2006 |\n| -------------- | ----------------------------- | ------ |\n\n| Applicability: | All Models BAe 146 and AVRO 146-RJ series aeroplanes. |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | Modify the nose landing gear per SB 32-174-70676A Initial issue or later EASA approved revision.Note: EASA AD 2006-0137 dated 23 May 2006 refers. |\n| Compliance: | Prior to 31 May 2007. |\n| | This Airworthiness Directive becomes effective on 3 August 2006. |\n| Background: | The BAe146 nose wheel assembly abutment ring is manufactured with an internal chamfer on one side, so when correctly installed, the wheel clamping loads are not applied to the machined radius at the root of the stub axle. If installed incorrectly, i.e. the wrong way round, the abutment ring is displaced outboard from the correct position. This configuration allows the wheel to be installed but the wheel nut locking bolts will not be fully engaged. Normal operational forces can then cause the wheel nut to loosen and the wheel assembly to detach from the aircraft. In addition, the wheel clamping loads are applied to the stub axle radius, which may result in damage.This AD requires the replacement of the existing nose wheel abutment rings with revised nose wheel abutment rings. The ring ensures that if during a wheel change, the abutment ring is fitted the wrong way round, will prevent the nose wheel retaining nut from engaging with the axle threads. |\n\n![](image.001.png) \nJames Coyne \nDelegate of the Civil Aviation Safety Authority\n\n20 June 2006","sortOrder":0},{"sectionNumber":"AD/BAe 146/122","sectionType":"part","heading":"AD/BAe 146/122","content":"## AD/BAe 146/122","sortOrder":1},{"sectionNumber":"Nose Landing Gear Axle Spacer","sectionType":"part","heading":"Nose Landing Gear Axle Spacer","content":"## Nose Landing Gear Axle Spacer","sortOrder":2},{"sectionNumber":"8/2006","sectionType":"part","heading":"8/2006","content":"## 8/2006","sortOrder":3}],"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — a targeted safety fix for a specific mechanical defect in a specific aircraft type. There is no evidence of scope creep; it addresses exactly the nose landing gear abutment ring issue it was designed to solve."},"complexity_factors":["Single, specific mechanical modification required","Only one defined compliance pathway (follow Service Bulletin SB 32-174-70676A)","No nested exceptions or conditional logic","Clear applicability (all models of two specific aircraft series)","Single deadline with no phased compliance options","Background explanation provided in plain technical language"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of BAe 146 and AVRO 146‑RJ aircraft in Australia to replace the nose‑landing‑gear abutment ring with a redesigned part. The original ring could be fitted backwards during maintenance, risking a loose wheel nut, loss of the nose wheel in flight, and axle damage. The new ring cannot be installed incorrectly. The modification deadline was 31 May 2007."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"This AD aligns with and implements the scope of the referenced EASA AD by mandating replacement of the nose wheel abutment ring on the same aircraft models. It does not broaden applicability beyond the BAe 146/AVRO 146‑RJ series or add additional regulatory duties beyond the service‑bulletin‑specified modification."},"complexity_factors":["Safety‑critical but narrowly scoped: mandates replacement of a single component on specified aircraft models (Applicability: All Models BAe 146 and AVRO 146‑RJ series aeroplanes).","Technical specificity: requires following BAe Service Bulletin 32‑174‑70676A (or later EASA‑approved revision) for the modification (Requirement).","Regulatory cross‑reference: implements an EASA AD (EASA AD 2006‑0137), adding a compliance linkage across regulators (Background/Note).","Fixed compliance deadline creates scheduling pressure for operators (Compliance: Prior to 31 May 2007).","Compliance burden lies with operators: parts procurement, maintenance labour, and aircraft downtime are borne by owners/operators (implied by Requirement/Applicability).","Low administrative discretion: directive is prescriptive (replace part per SB) and issued by CASA (Delegate signature), leaving little room for alternative means without approval.","Implementation risk limited to logistics: sourcing revised abutment rings and arranging maintenance, rather than complex inspections or repeated monitoring."],"plain_english_summary":"This Airworthiness Directive requires all BAe 146 and AVRO 146‑RJ operators to replace the nose‑wheel abutment (axle spacer) with a revised part so a mis‑fitted ring cannot allow the nose wheel nut to loosen and the wheel to detach. It is safety‑directed, references a specific BAe service bulletin and an EASA AD, and must be completed by 31 May 2007. Operators (owners) bear the cost and schedule the work."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bae-146-122-nose-landing-gear-axle-spacer","history":"/api/acts/ad-bae-146-122-nose-landing-gear-axle-spacer/history","analysis":"/api/acts/ad-bae-146-122-nose-landing-gear-axle-spacer/analysis","conflicts":"/api/acts/ad-bae-146-122-nose-landing-gear-axle-spacer/conflicts","importantCases":"/api/acts/ad-bae-146-122-nose-landing-gear-axle-spacer/important-cases","documents":"/api/acts/ad-bae-146-122-nose-landing-gear-axle-spacer/documents"}}