{"id":"F2006B06849","name":"AD/SD3-30/5 - Aileron, Pilots Handwheel Stop - Modification","slug":"ad-sd3-30-5-aileron-pilots-handwheel-stop-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114719,"registerId":"commonwealth-F2006B06849-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SD3-30/5 - Aileron, Pilots Handwheel Stop - Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Short SD3-30 Series Aeroplanes\n\n \n\nAD/SD3-30/5 Aileron, Pilots Handwheel Stop - Modification 1/82\n\nApplicability: SD 3-30 aircraft with S/Nos. SH 3002 to SH 3067 fitted with PT6A-45R engines (SB SD3-71-11), and S/Nos. SH 3068 to SH 3071, SH 3073, SH 3075, SH 3077 and SH\n\n3078.\n\n \n\nDocument: Shorts SB No. SD3-27-23.\n\n \n\n(Modification No. 6255).\n\n \n\nCompliance: Unless already accomplished, within 400 hours time in service after 31 January 1981.\n\n \n\nBackground:  During flight testing after fitting PT6A-45R engines, it was found that in some low weight configurations the aircraft was marginally below the required VMCL rate of roll.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive, as published, sets a targeted modification for identified SD3-30 serial numbers with specific engine installations to correct a VMCL roll-rate deficiency discovered during post-installation flight testing. The AD's scope is limited to the listed aircraft and engine fitment and prescribes a single modification (Modification No. 6255) to be completed within the stated compliance window; there is no indication in the text that the scope has been expanded or narrowed from that original stated purpose."},"complexity_factors":["Narrow, serial-number-limited applicability tied to a specific engine fitment (Applicability)","Dependence on an external technical document (Shorts SB No. SD3-27-23) to carry out the modification (Document)","A single compliance deadline expressed in flight hours after a calendar date (Compliance)","Technical safety trigger based on VMCL roll-rate findings during flight testing (Background)"],"plain_english_summary":"### What this directive requires\n\nThis Civil Aviation Safety Authority Airworthiness Directive (AD/SD3-30/5) mandates a physical modification to the aileron pilot handwheel stop on specified Short SD3-30 aeroplanes (identified by serial numbers and engine fitment). The required work is described in the referenced Shorts service bulletin (SB No. SD3-27-23) and is recorded as Modification No. 6255. (Document; Modification No.)\n\n### Which aircraft are affected\n\n- SD3-30 aircraft with serial numbers SH 3002 to SH 3067 that have been fitted with PT6A-45R engines in accordance with SB SD3-71-11; and\n- SD3-30 aircraft with serial numbers SH 3068 to SH 3071, SH 3073, SH 3075, SH 3077 and SH 3078. (Applicability)\n\n### When it must be done\n\nIf the modification has not already been carried out, it must be completed within 400 hours time-in-service after 31 January 1981. (Compliance)\n\n### Why the change was ordered (the stated purpose)\n\nFlight testing after fitting PT6A-45R engines showed that, in some low-weight configurations, affected aeroplanes were marginally below the required VMCL (minimum control speed with the critical engine inoperative) rate of roll. The AD directs the aileron/pilot handwheel stop modification to address that condition. (Background)\n\n### Who acts and who bears the burden\n\n- The AD is issued under Commonwealth civil aviation authority and sets the requirement. (Document)\n- Aircraft operators or owners of the affected serial-numbered aeroplanes must have the modification accomplished within the stated compliance window unless it has already been done. (Compliance)\n\nMechanically, operators must follow Shorts SB No. SD3-27-23 to carry out Modification No. 6255; that is the documented procedure the AD points to. (Document; Modification No.)\n\n### Practical trade-offs, incentives and implementation notes\n\n- The stated safety trigger is a measured shortfall in VMCL roll rate after engine change (Background). The AD's mechanism is a mandated hardware modification specific to the affected fleet and engine fitment. (Applicability; Background)\n- The direct effect on operators is a one-off maintenance action to be scheduled and performed within the 400-hour window; the AD does not itself state costs or who pays, but compliance implies operators must allocate maintenance time and resources. (Compliance)\n- The AD is narrowly targeted by serial number and by engine fitment, so it concentrates the modification requirement on a defined subset of aircraft rather than applying fleet-wide. (Applicability)\n- The AD relies on an external service bulletin (Shorts SB No. SD3-27-23) as the technical means to implement the change; operators must obtain and follow that SB to comply. (Document)\n\n### Implementation risks and uncertainties highlighted by the source\n\n- The background identifies the flight-test finding that prompted the AD (Background), but the AD text does not include post-modification performance data or detailed cost/ downtime estimates. Operators will need to rely on the referenced service bulletin and maintenance providers for technical detail and scheduling.\n\n(References in parentheses indicate the part of the AD where each point is stated: Applicability; Document; Modification No.; Compliance; Background.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted airworthiness directive addressing a specific technical safety issue identified during flight testing. It has not expanded beyond its original purpose of mandating a single mechanical modification for a defined subset of aircraft."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 4 defined elements: specific aircraft serial numbers, engine type, service bulletin reference, and modification number","Single compliance condition with one exception clause ('Unless already accomplished')","No cross-references to other legislation or regulations beyond the enabling Civil Aviation Regulations 1998","Straightforward technical background with no nested exceptions or conditional logic"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires specific aircraft owners to make a physical modification to their planes.\n\n**What it does:**\n- Requires owners of certain **Short SD3-30 series aircraft** (a type of regional turboprop plane) to install a modified **pilot's handwheel stop** on the aileron controls.\n- An aileron is a hinged surface on the wing that helps the plane roll (bank) left or right. The \"handwheel stop\" limits how far the pilot can turn the control wheel.\n\n**Who it affects:**\n- Owners/operators of specific Short SD3-30 aircraft with serial numbers SH 3002 through SH 3067 (if fitted with PT6A-45R engines), plus serial numbers SH 3068-SH 3071, SH 3073, SH 3075, SH 3077, and SH 3078.\n\n**Why it matters:**\n- During flight testing with upgraded PT6A-45R engines, engineers discovered that in certain light-weight configurations, the aircraft couldn't roll fast enough to meet the minimum safety standard for **VMCL** (the minimum control speed with the critical engine inoperative — basically, the slowest speed at which the pilot can still keep the plane under control if one engine fails).\n- The modification ensures the pilot can't over-control the ailerons in a way that would worsen this problem.\n\n**Compliance deadline:**\n- The modification must be completed within **400 hours of flight time** after 31 January 1981, unless already done.\n\n**How to comply:**\n- Follow the manufacturer's Service Bulletin (Shorts SB No. SD3-27-23) and Modification No. 6255."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sd3-30-5-aileron-pilots-handwheel-stop-modification","history":"/api/acts/ad-sd3-30-5-aileron-pilots-handwheel-stop-modification/history","analysis":"/api/acts/ad-sd3-30-5-aileron-pilots-handwheel-stop-modification/analysis","conflicts":"/api/acts/ad-sd3-30-5-aileron-pilots-handwheel-stop-modification/conflicts","importantCases":"/api/acts/ad-sd3-30-5-aileron-pilots-handwheel-stop-modification/important-cases","documents":"/api/acts/ad-sd3-30-5-aileron-pilots-handwheel-stop-modification/documents"}}