{"id":"F2006B04952","name":"AD/CESSNA 170/19 Amdt 1 - Pneumatic Stall Warning System","slug":"ad-cessna-170-19-amdt-1-pneumatic-stall-warning-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44820,"registerId":"commonwealth-F2006B04952-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 170/19 Amdt 1 - Pneumatic Stall Warning System","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)  \nCessna 170, 172, F172, FR172 and 175 Series Aeroplanes\n\nAD/CESSNA 170/19\n\nAmdt 1\n\n  \nPneumatic Stall Warning System 6/83\n\nApplicability: All models with pneumatic stall warning systems not incorporating horn reed assembly P/N 0413483-2, P/N 0713348-1 or subsequent and protective screens over the horn bell and stall warning system opening on the left wing.\n\nRequirement: 1. Check the pneumatic stall warning system for correct operation by applying a slight suction with the mouth at the stall warning opening in the left wing. A properly functioning horn will provide a sound that is clearly audible. It may be advisable to first cover the opening with a clean piece of cloth. Cessna 100 Series Service Manual 1963 to 1967 Section 16 refers.\n\nNote: This check may be performed and certified by the pilot.\n\n    2. Install the following placard in full view of the pilot:\n\n“PRE-FLIGHT TEST THE PNEUMATIC STALL WARNING SYSTEM”.\n\n    3. The requirements of paragraphs 1 and 2 may be removed by incorporation of the following modifications. Replace the stall warning reed assembly P/N 0413028-1 with reed assembly P/N 0413483-2, P/N 0713348-1 or subsequent and install an 18 x 14 or 18 x 16 mesh screen over the exposed horn bell inside the cabin and over the left wing opening. Flight test the aircraft to assure the stall warning horn sounds at 5 to 10 knots above the stalling speed.\n\nCompliance: For para. 1 \\- Before each flight.\n\nFor para. 2 \\- Within 25 hours time in service after 3 September 1968.\n\nBackground: This amendment reflects latest Cessna Part Number change.","sortOrder":0}],"analysis":{"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is an amendment to an existing Airworthiness Directive (AD/CESSNA 170/19). The amendment is minor — it simply updates the part number reference to reflect Cessna's latest manufacturing change. The scope remains exactly as originally intended: ensuring stall warning system reliability on specific Cessna aircraft models. No expansion of applicability or requirements beyond the original safety purpose."},"complexity_factors":["Single, specific technical subject matter (pneumatic stall warning systems on specific Cessna models)","Only 3 main requirements with clear compliance deadlines","Minimal defined terms (only specific part numbers referenced)","No cross-references to other legislation beyond a single service manual citation","Straightforward conditional logic: either comply with ongoing checks OR perform permanent modification to remove ongoing obligations","Short document (approximately 250 words)"],"plain_english_summary":"This CASA Airworthiness Directive targets older Cessna 170/172/F172/FR172/175 aeroplanes with legacy pneumatic stall‑warning horns. Owners/operators without upgraded reed assemblies or horn screens must perform a pre‑flight suction test to confirm the horn sounds, install a cockpit placard reminding pilots to test, or optionally fit approved reed and mesh upgrades and flight‑test the system. It’s aimed at preventing silent stall warnings that could lead to loss of control."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment updates and clarifies applicable part numbers and specifies protective screen mesh sizes but does not broaden or narrow the set of affected aircraft or add new types of requirements; existing pre‑flight test, placard, and modification options remain in place (see Background: part number change)."},"complexity_factors":["Narrow applicability: specific Cessna models and pneumatic stall warning systems","Simple, discrete compliance actions (pre‑flight suction test; placard installation)","Clear modification path that removes recurring requirements (specified P/N replacements and mesh screens)","Technical specifics present but limited (exact part numbers, mesh sizes, flight‑test tolerance)","Pilot may perform and certify the check, reducing administrative burden"],"plain_english_summary":"This directive applies to Cessna 170/172/175-series aeroplanes using older pneumatic stall‑warning systems. It requires the pilot to perform a simple mouth‑suction pre‑flight check before every flight and to fit a visible cockpit placard within 25 hours, unless the owner replaces the reed assembly with specified part numbers and fits protective screens and then flight‑tests the horn to confirm it sounds 5–10 knots above stall. Owners/operators pay for parts/installation; pilots perform and certify the check, changing pre‑flight routine and equipment costs."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-170-19-amdt-1-pneumatic-stall-warning-system","history":"/api/acts/ad-cessna-170-19-amdt-1-pneumatic-stall-warning-system/history","analysis":"/api/acts/ad-cessna-170-19-amdt-1-pneumatic-stall-warning-system/analysis","conflicts":"/api/acts/ad-cessna-170-19-amdt-1-pneumatic-stall-warning-system/conflicts","importantCases":"/api/acts/ad-cessna-170-19-amdt-1-pneumatic-stall-warning-system/important-cases","documents":"/api/acts/ad-cessna-170-19-amdt-1-pneumatic-stall-warning-system/documents"}}