{"id":"F2007L02120","name":"AD/G1159/47 - Nose Wheel Steering Control","slug":"ad-g1159-47-nose-wheel-steering-control","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":67249,"registerId":"commonwealth-F2007L02120-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Gulfstream (Grumman) G1159 and G-IV Seri","sectionType":"division","heading":"Gulfstream (Grumman) G1159 and G-IV Series Aeroplanes","content":"### Gulfstream (Grumman) G1159 and G-IV Series Aeroplanes\n\n| AD/G1159/47 | Nose Wheel Steering Control | 8/2007 |\n| ----------- | --------------------------- | ------ |\n\n| Applicability: | Model G-V series aeroplanes, serial numbers 501 and subsequent.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement:   | Replace the nose wheel steering actuator, part number (P/N) 1159SCL500-41 Rev. D, with a new or restored actuator having the same part number, in accordance with Gulfstream V Maintenance Manual Chapter 05-10-00.Optional Terminating ActionReplacement of all nose wheel steering actuators with new improved actuators having P/N 1159SCL500-51, per Gulfstream V Maintenance Manual Chapter 05-10-00, provides terminating action for the repetitive replacement requirements specified in this AD.Note: FAA AD 2001-14-16 Amdt 39-12327 dated 10 July 2001 refers. |\n| Compliance:    | At whichever occurs later:- Within 450 flight hours or 12 months after replacing the nose wheel steering actuator, P/N 1159SCL500-4l Rev. D, with a new or restored actuator having the same part number, whichever occurs first; or- Within 30 days after the effective date of this AD.Thereafter repeat this replacement every 450 flight hours or 12 months, whichever occurs first.                                                                                                                                                                                 |\n|                | This Airworthiness Directive becomes effective on 2 August 2007.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |\n\n| Background: | The actions within this AD are intended to prevent loss of nose wheel steering control, without a corresponding alert message annunciation, due to the effects of moisture intrusion into the rotary variable displacement transducer (RVDT) inside the steering actuator, which could result in the aeroplane departing the runway if an over steering condition were to occur during landing. |\n| ----------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nDavid Punshon  \nDelegate of the Civil Aviation Safety Authority\n\n21 June 2007","sortOrder":0},{"sectionNumber":"AD/G1159/47","sectionType":"part","heading":"AD/G1159/47","content":"## AD/G1159/47","sortOrder":1},{"sectionNumber":"Nose Wheel Steering Control","sectionType":"part","heading":"Nose Wheel Steering Control","content":"## Nose Wheel Steering Control","sortOrder":2},{"sectionNumber":"8/2007","sectionType":"part","heading":"8/2007","content":"## 8/2007","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD's scope is consistent with its stated intent: prevent loss of nose wheel steering caused by moisture intrusion into the actuator RVDT by mandating repeated replacement or offering an improved actuator as terminating action. It applies only to Gulfstream G‑V aeroplanes, serial numbers 501 onward (Applicability; Background; Requirement), and the instrument does not indicate any expansion or narrowing of that scope beyond what is expressed in the AD text."},"complexity_factors":["Recurring maintenance mandate with dual time/usage limits: 450 flight hours or 12 months, and a 30‑day initial compliance window (Compliance).","Specific part numbers and revision control drive compliance: P/N 1159SCL500‑41 Rev. D (replace or restore) and optional terminating P/N 1159SCL500‑51 (Requirement).","Applicability limited to a subset of fleet (G‑V series, serials 501 and subsequent), concentrating costs on those operators (Applicability).","Implementation directed via the Gulfstream V Maintenance Manual Chapter 05‑10‑00, requiring maintenance-resource alignment and recordkeeping (Requirement).","Safety rationale tied to a single failure mode (moisture ingress to the RVDT) rather than broad system redesign, limiting technical scope but creating recurring operational cost (Background).","Short mandatory compliance timeline for initial action (within 30 days after AD effective date) increases near‑term operational disruption risk for affected operators (Compliance).","Optional terminating action reduces long‑term repetition but requires acquisition/installation of a different P/N, shifting upfront capital cost versus ongoing maintenance expense (Requirement).","Reference to prior FAA AD for context but no procedural harmonisation detail in the text, leaving procedural discretion to operators and maintenance organisations (Requirement/Note)."],"plain_english_summary":"This directive requires operators of Gulfstream G‑V aeroplanes (serial numbers 501 and later) to replace the nose‑wheel steering actuator P/N 1159SCL500‑41 Rev. D with a new or restored unit on a recurring schedule (every 450 flight hours or 12 months), or install an improved actuator P/N 1159SCL500‑51 as an optional terminating action. It addresses moisture ingress in the actuator’s RVDT that can cause unannunciated loss of nose‑wheel steering and possible runway departure."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, targeted airworthiness directive addressing a specific mechanical defect in a specific aircraft type. The scope remains precisely limited to nose wheel steering actuator replacement on Gulfstream G-V series aircraft, with no evidence of scope creep beyond the original safety purpose."},"complexity_factors":["Very short document (approximately 300 words)","Only 1 defined term (RVDT - rotary variable displacement transducer)","Simple conditional logic: 'whichever occurs later/first' timing provisions","Single mechanical part replacement requirement with clear alternative terminating action","No cross-references to other legislation beyond a note about the related FAA directive","Straightforward applicability: single aircraft model, specific serial number range"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of Gulfstream G‑V jets (serials 501+) to stop using a nose‑wheel steering actuator (p/n 1159SCL500‑41 Rev. D) that can let moisture into its RVDT sensor and cause silent steering failure on landing.  \n\nAffected aircraft must have the actuator replaced within the stated compliance window and then on a recurring 450 flight‑hour/12‑month cycle, unless swapped for the improved p/n 1159SCL500‑51, which ends the repetitive requirement. Effective 2 August 2007."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-g1159-47-nose-wheel-steering-control","history":"/api/acts/ad-g1159-47-nose-wheel-steering-control/history","analysis":"/api/acts/ad-g1159-47-nose-wheel-steering-control/analysis","conflicts":"/api/acts/ad-g1159-47-nose-wheel-steering-control/conflicts","importantCases":"/api/acts/ad-g1159-47-nose-wheel-steering-control/important-cases","documents":"/api/acts/ad-g1159-47-nose-wheel-steering-control/documents"}}