{"id":"F2006B09711","name":"AD/F27/144 - Emergency Lighting","slug":"ad-f27-144-emergency-lighting","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115883,"registerId":"commonwealth-F2006B09711-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F27/144 - Emergency Lighting","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)  \nFokker F27 Series Aeroplanes\n\nAD/F27/144 Emergency Lighting 12/97\n\nApplicability: All Fokker Aircraft B.V. Model F.27 Mk.050, Mk0502, and Mk.0604 if Emergency Battery Power Supply Unit, Part Number 60-4915-1 is installed.\n\nRequirement: Fabricate a placard, with the following words in letters at least 2.5mm (0.10 inches) in height and install the placard in clear view of the pilot adjacent to the Emergency Lighting Selector Switch:\n\nCAUTION\n\nWHEN CYCLING EMERGENCY LIGHTING SELECTOR, SWITCH MUST BE LEFT IN “OFF” POSITION FOR AT LEAST 60 SECONDS.\n\nNote: Netherlands AD 1997-060 (A) refers.\n\nCompliance: By the 11 February 1998.\n\nThis airworthiness directive becomes effective on 6 November 1997.\n\nBackground: Pre delivery testing on a Fokker Model F.27 Mk 050 aircraft has shown that, if the flight crew cycles the Emergency Lighting Selector Switch, within a short time period, to OFF, either from ARMED or ON, and subsequently back to ARMED, the system will actually not be armed. If this switching sequence has occurred, the system will not react either in the event of an electrical power failure, nor when the switch is moved to the ON position. The affected circuitry, which needs a certain time to reset, is only installed in the Emergency Battery Power Supply units identified above.","sortOrder":0}],"analysis":{"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a targeted safety directive addressing a specific technical fault identified in pre-delivery testing. The scope remains precisely limited to the identified aircraft configuration and the specific remedy (placard installation)."},"complexity_factors":["Single, specific technical requirement (fabricate and install placard)","Minimal defined terms (only specific part numbers and aircraft models)","No cross-references to other legislation sections","Simple conditional logic (only applies to specific part number)","Short document (under 200 words)","Clear compliance deadline and effective date"],"plain_english_summary":"This airworthiness directive requires operators of Fokker F27 Mk.050, Mk0502 and Mk.0604 aircraft fitted with Emergency Battery Power Supply Unit P/N 60‑4915‑1 to install a warning label by 11 Feb 1998 near the emergency lighting switch. The placard tells crews to leave the switch OFF for at least 60 seconds when cycling it because rapid switching can leave the system appearing armed but actually unarmed, risking loss of emergency lighting during evacuations."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive limits obligations to aircraft of the listed Fokker models that have the specified battery power supply unit installed and mandates a placard plus procedural compliance. It does not broaden applicability beyond that technical subset or add other equipment/inspection mandates, so the scope is consistent with the stated safety issue."},"complexity_factors":["Narrow technical applicability — only specific Fokker F.27 models with Emergency Battery Power Supply Unit P/N 60-4915-1 are affected (Applicability).","Single, simple mandated action — fabricate and install a 2.5 mm-letter placard adjacent to the selector (Requirement).","Safety-critical operational behavior change — pilots must wait 60 seconds when cycling the switch; effectiveness depends on crew adherence (Requirement / Background).","Low implementation cost but non-zero compliance burden on operators to produce, install and monitor placard use (Requirement / Compliance).","Root cause is electrical/reset timing in a specific unit, not airframe-wide — limits technical remediation to affected units (Background).","Reference to foreign directive (Netherlands AD) indicates reliance on overseas certification findings (Note).","Short compliance timeline creates administrative scheduling for operators (Compliance)."],"plain_english_summary":"This airworthiness directive requires operators of certain Fokker F.27 Mk.050, Mk0502 and Mk.0604 aircraft fitted with Emergency Battery Power Supply Unit P/N 60-4915-1 to install a cockpit placard telling pilots to leave the Emergency Lighting Selector OFF for at least 60 seconds when cycling. CASA sets the compliance date; aircraft operators pay to fabricate and fit the placard and must ensure crew follow the procedure. The measure responds to a reset-time fault in the battery unit that can leave emergency lighting unarmed after rapid switching."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f27-144-emergency-lighting","history":"/api/acts/ad-f27-144-emergency-lighting/history","analysis":"/api/acts/ad-f27-144-emergency-lighting/analysis","conflicts":"/api/acts/ad-f27-144-emergency-lighting/conflicts","importantCases":"/api/acts/ad-f27-144-emergency-lighting/important-cases","documents":"/api/acts/ad-f27-144-emergency-lighting/documents"}}