{"id":"F2010L01275","name":"CASA 142/10 – Directions and determinations – Class D airspace","slug":"casa-142-10-directions-and-determinations-class-d-airspace","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":83629,"registerId":"commonwealth-F2010L01275-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"CASA 142/10 – Directions and determinations – Class D airspace","content":"Instrument number CASA 142/10\n\nI, john francis McCORMICK, Director of Aviation Safety, on behalf of CASA, make this instrument under subregulations 92 (2) and 99AA (5) of the Civil Aviation Regulations 1988.\n\n\\[Signed John F. McCormick\\]\n\nJohn F. McCormick  \nDirector of Aviation Safety\n\n25 May 2010\n\nDirections and determinations — Class D airspace\n\n1 Commencement\n\nThis instrument commences on 3 June 2010.\n\n2 Revocation\n\nThe following instruments are revoked:\n\n(a) CASA 330/09;\n\n(b) CASA 597/09.\n\n3 Application\n\nThis instrument applies to:\n\n(a) each pilot operating an aircraft in Class D airspace; and\n\n(b) each pilot operating an aircraft into, or out of, an aerodrome in Class D airspace.\n\n4 Directions and determinations\n\nI give the directions, and make the determinations, contained in Schedule 1.\n\nSchedule 1 Directions and determinations\n\n1 Definition\n\nIn this instrument:\n\nrelevant ATC tower means the air traffic control tower or other facility that provides air traffic services for a particular Class D control zone (CTR) or its associated Class D airspace.\n\n2 Communications\n\nArrival or through flight\n\n2.1 Before entering Class D airspace, the pilot must establish 2-way radio communication with the relevant ATC tower.\n\n2.2 While within Class D airspace, the pilot must maintain 2-way radio communication with the relevant ATC tower.\n\nClearance for landing, take\\-off and manoeuvring area\n\n2.3 When a relevant ATC tower is in operation at an aerodrome, the pilot may only land at, take off from, or operate on the manoeuvring area of, that aerodrome if he or she has appropriate clearance from the tower.\n\n> Note Manoeuvring area is defined in the Air Services Regulations 1995 as any part of an aerodrome that is used for the take-off and landing of aircraft and for the movement of aircraft in association with take-off and landing, but does not include any apron.\n\nDeparting flight\n\n2.4 When a relevant ATC tower is in operation at an aerodrome, the pilot must:\n\n(a) before entering the manoeuvring area of the aerodrome, establish 2-way radio communication with the tower; and\n\n(b) maintain that communication while on the manoeuvring area or within the Class D airspace, unless the tower instructs otherwise.\n\n2.5 At a non-towered aerodrome in a Class D CTR, the pilot must:\n\n(a) before departing, establish 2-way radio communication with the relevant ATC tower; and\n\n(b) maintain that communication while within the Class D airspace, unless the relevant tower instructs otherwise.\n\n3 Airspeed limit below 2 500 ft\n\nUnless otherwise permitted by the relevant ATC tower, the pilot in Class D airspace must not exceed an airspeed limit of 200 KT if he or she is:\n\n(a) within 4 nautical miles of the tower; and\n\n(b) flying at or below 2 500 ft above the ground.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The instrument expressly revokes CASA 330/09 and CASA 597/09 (cl.2) and replaces them with the directions in Schedule 1. It therefore alters the operative text governing pilots in Class D airspace and those operating into or out of aerodromes in Class D (cl.3), while keeping operational discretion with the relevant ATC tower (Schedule 1)."},"complexity_factors":["Multiple mandatory communications and clearance obligations (Schedule 1 cl.2.1–2.5) increase procedural compliance for pilots.","Different rules depending on whether an aerodrome has an operating tower or is non‑towered (cl.2.3–2.5).","Operational discretion vested in the relevant ATC tower to permit exceptions or instruct otherwise (cl.2.4(b), cl.2.5(b), cl.3).","Conditional airspeed limit tied to distance and altitude (200 KT within 4 NM and ≤2,500 ft) requiring situational awareness and monitoring (cl.3).","Cross‑references to external definitions and instruments (Civil Aviation Regulations subregs 92(2), 99AA(5); Air Services Regulations definition of manoeuvring area noted in cl.2.3).","Revocation of prior instruments (cl.2) requires operators to track changes and new text rather than rely on legacy guidance.","Short instrument length lowers interpretive burden, but reliance on operational exchange with ATC shifts complexity to real‑time compliance."],"plain_english_summary":"Requires pilots in or transiting Class D airspace to establish and maintain two‑way radio communication with the relevant ATC tower, obtain tower clearance to land, take off or use manoeuvring areas when the tower is operating, and observe a 200 KT speed limit within 4 NM and at or below 2,500 ft unless the tower permits otherwise (`Schedule 1 cl.2.1–2.5; cl.3`).\n\nPilots carry the compliance burden; relevant ATC towers hold operational discretion to grant exceptions or instruct otherwise. The instrument replaces CASA 330/09 and CASA 597/09 (cl.2)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The instrument remains tightly focused on its original purpose: establishing communication and operational rules for Class D airspace. It consolidates two previous instruments without expanding into new regulatory areas."},"complexity_factors":["Short instrument: 5 substantive sections plus a brief Schedule","Only 1 defined term ('relevant ATC tower')","Minimal cross-referencing (only references to Civil Aviation Regulations 1988 for making power, and Air Services Regulations 1995 for 'manoeuvring area' definition)","Clear conditional structure (if tower is operating vs. non-towered aerodromes)","No nested exceptions or complex logical operators"],"plain_english_summary":"This rule sets safety rules for pilots in Class D airspace: mandatory radio contact with ATC before and during entry, explicit tower clearance for landings/take-offs and manoeuvring area movements when the tower is operating, and a 200‑knot speed limit within 4 NM and below 2,500 ft unless ATC directs otherwise. It applies to any pilot operating into, out of, or through Class D airspace and consolidates two earlier instruments into one to reduce collision risk."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/casa-142-10-directions-and-determinations-class-d-airspace","history":"/api/acts/casa-142-10-directions-and-determinations-class-d-airspace/history","analysis":"/api/acts/casa-142-10-directions-and-determinations-class-d-airspace/analysis","conflicts":"/api/acts/casa-142-10-directions-and-determinations-class-d-airspace/conflicts","importantCases":"/api/acts/casa-142-10-directions-and-determinations-class-d-airspace/important-cases","documents":"/api/acts/casa-142-10-directions-and-determinations-class-d-airspace/documents"}}