{"id":"F2006B04866","name":"AD/CASA/10 - Placard - Use of Reverse Thrust","slug":"ad-casa-10-placard-use-of-reverse-thrust","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44673,"registerId":"commonwealth-F2006B04866-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CASA/10 - Placard - Use of Reverse Thrust","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)  \nCasa 212 Series Aeroplanes\n\nAD/CASA/10 Placard \\- Use of Reverse Thrust 10/87\n\nDM\n\nApplicability: All model CASA C-212-( ) fitted with Garrett TPE-331 turboprop engines to which Hartzell model HC-B4(T,M)N-5( ) propellers are fitted.\n\nRequirement: Install a temporary placard in a suitable position in the cockpit worded as follows: “Until propellers are modified to Hartzell SB 153, avoid use of full reverse pitch.”\n\nCompliance: By 30 October 1987.\n\nBackground: During the past several months the four bladed steel hub propellers fitted to CASA C- 212-( ) series aircraft has experienced failure of the pitch change rod P/N B-3018S-2. Failure has occurred during ground operation with application of full reverse pitch.\n\nRod failure in this position will cause the propellers to travel deeper into reverse which could cause severe asymmetric thrust conditions or unacceptable engine overtemperature conditions.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive addressing a specific mechanical failure mode. It has not expanded beyond its original purpose of mitigating propeller pitch change rod failures through temporary cockpit warnings."},"complexity_factors":["Very short document (under 300 words)","Only 2 defined terms implicitly used (applicability criteria)","No cross-references to other legislation beyond the enabling Civil Aviation Regulations 1988","Single, unambiguous requirement with clear compliance date","No conditional logic or exceptions","Straightforward technical applicability based on aircraft model and engine/propeller combination"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's aviation regulator (CASA) requiring specific fixes to aircraft.\n\n**What it does:**\nOrders owners and operators of certain CASA C-212 aircraft to install a temporary warning sign (placard) in the cockpit. The sign must warn pilots not to use full reverse thrust on the propellers until they are modified according to a specific Hartzell service bulletin.\n\n**Who it affects:**\n- All CASA C-212 aircraft fitted with Garrett TPE-331 engines and Hartzell HC-B4(T,M)N-5( ) propellers\n- Aircraft operators, maintenance organisations, and pilots flying these specific planes\n\n**Why it matters:**\nThe propeller's pitch change rod (part number B-3018S-2) has been failing during ground operations when pilots use full reverse pitch. If this rod breaks, the propeller can swing deeper into reverse, creating two serious dangers:\n- **Asymmetric thrust** — one engine producing much more reverse thrust than the other, making the plane hard to control on the ground\n- **Engine overtemperature** — the engine overheating dangerously\n\nThe placard is a temporary safety measure until the propellers can be physically modified.\n\n**Deadline:**\nThe placard had to be installed by 30 October 1987."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive’s scope is limited and explicit: it applies only to CASA C-212-( ) aircraft with Garrett TPE-331 engines fitted with Hartzell HC-B4(T,M)N-5( ) propellers and requires a temporary placard and avoidance of full reverse until propellers are modified to Hartzell SB 153. The instrument does not indicate any expansion or narrowing of that defined applicability beyond the stated text (Applicability; Requirement)."},"complexity_factors":["Narrow applicability to a specific aircraft/engine/propeller combination (Applicability).","Single, clear remedial action (install a specific placard) with a fixed compliance date (Requirement; Compliance).","Technical references to specific parts and a propeller service bulletin (pitch change rod P/N B-3018S-2; Hartzell SB 153) introduce domain‑specific technical detail (Background; Requirement).","Operational trade‑off between immediate behavioural restriction and later physical modification (Background; Requirement)."],"plain_english_summary":"This AD requires operators of CASA C‑212 aeroplanes with Garrett TPE‑331 engines and Hartzell HC‑B4(...) propellers to install a cockpit placard warning to avoid use of full reverse pitch until the propellers are modified per Hartzell SB 153 (placard by 30 Oct 1987). \n\nIt responds to pitch‑rod failures that can allow deeper reverse, risking severe asymmetric thrust or engine overtemperature, and imposes a temporary operational restriction while incentivising the SB 153 modification."}},"importantCases":[],"_links":{"self":"/api/acts/ad-casa-10-placard-use-of-reverse-thrust","history":"/api/acts/ad-casa-10-placard-use-of-reverse-thrust/history","analysis":"/api/acts/ad-casa-10-placard-use-of-reverse-thrust/analysis","conflicts":"/api/acts/ad-casa-10-placard-use-of-reverse-thrust/conflicts","importantCases":"/api/acts/ad-casa-10-placard-use-of-reverse-thrust/important-cases","documents":"/api/acts/ad-casa-10-placard-use-of-reverse-thrust/documents"}}