{"id":"F2006B08332","name":"AD/CESSNA 400/46 Amdt 1 - Wing Tip Strobe Light - Inspection","slug":"ad-cessna-400-46-amdt-1-wing-tip-strobe-light-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115739,"registerId":"commonwealth-F2006B08332-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 400/46 Amdt 1 - Wing Tip Strobe Light - Inspection","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 400 Series Aeroplanes\n\nAD/CESSNA 400/46\n\nAmdt 1\n\n  \nWing Tip Strobe Light \\- Inspection 7/79\n\nApplicability: All models S/Nos. 401B0001 thru 401B0300, 402B0001 thru 402B0912, 414-0001 thru 414-0649, 421B0001 thru 421B0922 and 421B0924 thru 421B0927 equipped with strobe lights installed in wing tip fuel tank nose cap except those aeroplanes having Symbolic displays P/N 30-0005, 30-0199-3 and 701133-1; Whelen Engineering Co. Inc. P/N A430; and Grimes Manufacturing Co. P/N 30-0515-5, 30- 1172-1, 30-0531-1 and 30-0467-5, strobe lights.\n\nRequirement: 1. Deactivate the strobe light system by installing a guard over the switch and/or by pulling and locking the circuit breaker so that it cannot be inadvertently reset, or by any other suitable means.\n\n    2. Systems having Grimes P/N 30-0515-1 strobe lights may be reactivated upon the installation of Grimes P/N 31-1723-5 or 30-1171-1 cover plates in accordance with Cessna SL ME75-16. These cover plates may be identified by the presence of two quench tubes protruding into the light assembly from the end plate.\n\n    3. Do not reactivate other non excepted strobe light assemblies until data, showing that the strobe lights are explosion proof, has been submitted to and approved by the Secretary.\n\nCompliance: Within 100 hours time in service after 30 July 1976.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a focused, single-issue airworthiness directive addressing a specific safety defect in specific aircraft. It has not expanded beyond its original purpose of addressing explosion risks in wing tip strobe light installations."},"complexity_factors":["Multiple specific serial number ranges across four aircraft models (401B, 402B, 414, 421B)","Complex applicability clause with multiple exceptions based on manufacturer part numbers (7 specific part numbers exempted across three manufacturers)","Three-tiered requirement structure with conditional reactivation pathways","Reference to external technical document (Cessna Service Letter ME75-16)","Administrative approval requirement (Secretary approval for alternative compliance)"],"plain_english_summary":"This Airworthiness Directive orders owners/operators of specified Cessna 400-series twins (with certain serial numbers) to immediately deactivate wing-tip strobe lights installed in the wing-tip fuel tank nose cap because of an explosion risk. Systems using specified Grimes, Whelen, or Symbolic part numbers are exempt or may be reactivated if fitted with the approved Grimes cover plates; all other systems must remain disabled until proven explosion‑proof. Compliance was required within 100 flight hours after 30 July 1976."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"The amendment narrows a blanket deactivation by carving out specific P/N exceptions and permitting reactivation of Grimes P/N 30‑0515‑1 assemblies once fitted with specified cover plates per Cessna SL ME75‑16, while requiring Secretary approval for other reactivations (Applicability; Requirement 2–3). This introduces conditional reactivation paths and regulatory approval steps where a prior instrument may have required only deactivation."},"complexity_factors":["Serial‑number specific applicability requiring operators to check airframe S/N ranges against the AD (Applicability).","Multiple part‑number exceptions and physical identification criteria for exempted strobe assemblies, increasing inspection and parts‑verification tasks (Applicability; Requirement 2).","A technical modification pathway that references a Cessna Service Letter (SL ME75‑16) and specific cover plate P/Ns, creating dependence on external technical instructions (Requirement 2).","A submission/approval requirement: reactivation of non‑excepted assemblies only after the Secretary approves data showing the lights are explosion‑proof, introducing regulatory discretion and documentation burden (Requirement 3).","A short, operational compliance window (100 hours TIS after 30 July 1976) that pressures scheduling of inspections and modifications (Compliance).","Safety‑critical operational measures (guards, locked circuit breakers) that impose immediate procedural changes and potential downtime (Requirement 1)."],"plain_english_summary":"Requires owners/operators of specified Cessna 400‑series aeroplanes to deactivate wing‑tip strobe lights installed in wing‑tip fuel‑tank nose caps until they are modified or approved for reactivation (Applicability; Requirement 1–3). Owners must fit a guard, pull and lock the circuit breaker, or use another means to prevent inadvertent activation; compliance is within 100 hours TIS after 30 July 1976 (Requirement 1; Compliance). The Secretary may approve reactivation only on submission of explosion‑proof data (Requirement 3)."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-400-46-amdt-1-wing-tip-strobe-light-inspection","history":"/api/acts/ad-cessna-400-46-amdt-1-wing-tip-strobe-light-inspection/history","analysis":"/api/acts/ad-cessna-400-46-amdt-1-wing-tip-strobe-light-inspection/analysis","conflicts":"/api/acts/ad-cessna-400-46-amdt-1-wing-tip-strobe-light-inspection/conflicts","importantCases":"/api/acts/ad-cessna-400-46-amdt-1-wing-tip-strobe-light-inspection/important-cases","documents":"/api/acts/ad-cessna-400-46-amdt-1-wing-tip-strobe-light-inspection/documents"}}