Australian airspace regulations
Rev. 56 — page content was last changed October 6, 2009
consequent to editing by RA-Aus member Dave Gardiner www.redlettuce.com.au
| | Home | Flight Theory | Meteorology | Communications | Emergencies | Airmanship and safety | Operations manual | Search | |
|
Australian airspace regulationsRev. 56 — page content was last changed October 6, 2009 consequent to editing by RA-Aus member Dave Gardiner www.redlettuce.com.au |
| Flight Planning and Navigation |
|
To facilitate safe, orderly use of airspace there are two internationally agreed sets of flight rules — to which all airspace users must adhere — plus several classes of controlled airspace in which aircraft may operate to take advantage of the implied safety within that airspace. However, much of the Australian airspace below 18 000 feet above mean sea level [amsl] is classified as Class G and not controlled. This airspace is where most recreational aircraft generally operate.
1.1 Controlled airspace'Controlled airspace' is airspace of defined dimensions within which air traffic control service is provided in accordance with the airspace classification. There are two types of controlled airspace:
Please note: many people confusingly use the CTA abbreviation when they are referring to the generic controlled airspace (i.e. CTA plus CTR) rather than just Control Area(s). There is no abbreviation listed in the Australian Aeronautical Information Publication [AIP] for controlled airspace. Airspace classificationFour of the International Civil Aviation Organisation [ICAO] controlled airspace classes are currently used in Australia; A,C, D and E.Please note: RA-Aus Pilot Certificate holders must not fly an RA-Aus registered aircraft in Class A, C or D airspace unless they also hold a current aviation medical certificate and a valid pilot licence issued by the Civil Aviation Safety Authority, or unless CASA has issued a written approval for a particular flight or an official exemption for an ongoing activity; e.g. for an RA-Aus flight school operating within a Class D control zone. The ICAO does not recognise a 'pilot certificate' as a 'pilot licence' — that includes the United States 'Sport Pilot Certificate'.  In Australia, Class A is high-level en route airspace, and Class C surrounds major city airports starting at ground level and stepped up into mid-level Class C or the high-level Class A airspace. The control area — generally within secondary surveillance radar [SSR] coverage — between Sydney and Melbourne is designated Class E between 8500 feet amsl and FL125, Class C between FL125 and FL180, and Class A above FL180.  The control area — generally within SSR coverage — between Sydney and Cairns is designated Class E between 8500 feet and FL180, and Class A above FL180.  CTRs at smaller regional airports (which lack primary radar coverage) are Class D airspace; these are only active as such when the control tower at that CTR is manned. They revert to non-controlled airspace at the times when the tower is not manned. The CTR starts at the surface and is stepped up into the Class C approach/departure areas. The upper boundary of Class D is usually 4500 feet amsl. Transponders are not required in Class D CTRs. CAO 95.55 and CAO 95.32 aircraft may only enter and fly in Class C and D airspace if they meet all the conditions specified in CAO 95.55 paragraph 5.2 and CAO 95.32 paragraph 5.2. CAO 95.10 has no allowance for entry into Class C and D airspace. Class E airspaceAustralian Class E is mid-level en route airspace, the general base of which is at 8500 feet amsl within SSR coverage and at FL180 in the remaining continental area. However, there are three Class E corridors with the base at FL125 and extending up to the overlying Class A. All aircraft require a clearance from ATC before entering Class A, B and C airspace, and a transponder must be operated. VHF radio-equipped VFR aircraft (including RA-Aus aircraft) may operate in Class E airspace without an Air Traffic clearance, but the pilot must:
RA-Aus aircraft operating in Class E must be equipped with a serviceable VHF communications system. The AIP Book is perhaps at variance with the CARs and CAOs, so it is not absolutely clear whether a hand-held unit is acceptable in controlled airspace. Hand-held transceivers approved by the Australian Communications and Media Authority are acceptable for use in RA-Aus registered aircraft operating in Class G airspace. See AIP GEN section 1.5 paragraphs 1.1, 1.2 and 1.5. The pinkish tinge covering most of the continent in the image below indicates the general FL180 Class E base, the tan colour indicates the areas within radar coverage where the Class E base is either at 8500 feet or FL125, and the green colour indicates where the Class E does not exist (i.e. Class C CTRs extend up to the base of Class A airspace) or Class C extends to the upper level of a Class D CTR.  In Class E, all flights operating under the instrument flight rules [IFR] are provided with an air traffic control separation service; hence, it is controlled airspace even though VFR flights within the same airspace are not provided with a traffic separation service — though they may be provided with a radar information service [RIS] on request if the controllers have the capacity to do so. However, "due to the nature and type of radar coverage (in Class E), not all aircraft will be observed on radar". An aircraft operating under the VFR that encounters instrument meteorological conditions must then obtain a clearance to continue the flight under the IFR.
GAAP control zonesIn Australia, there are six major city airfields that are dedicated to General Aviation purposes (i.e. no regular public transport [RPT] operations) for which some non-ICAO standard control zone procedures apply. These are Jandakot, Parafield, Moorabbin, Camden, Bankstown and Archerfield. Ministerial national airspace policy defined GAAP as an 'additional air traffic control procedure termed General Aviation Airport Procedures used in Class D airspace'. Airservices Australia is required to provide a Class D Air Traffic Service at the current GAAPs by 21 April 2010. |
1.2 Class G airspaceIn Australia, all airspace that is not promulgated as class A, C, D, E, GAAP or 'special use' is Class G, and is open without restriction for flight at or below 5000 feet amsl to all holders of a valid RA-Aus Pilot Certificate flying any RA-Aus registered aircraft. Class G extends over most of Australia from surface level to the overlying Class E base at 8500 feet amsl, FL125 or FL180. Airservices Australia provides a VHF or HF radio flight information service [FIS] for aircraft operating in Class G. The information service is provided within flight information areas [FIA] and the information delivered, via VHF or HF radio, includes weather and NOTAM. FIS also provides the SARWATCH search and rescue monitoring service. These FIAs are contained within two administrative regions known as Flight Information Regions [FIRs], one headquartered in Brisbane (BN) and the other in Melbourne (ML).
Operations at aerodromes in Class GTo maintain safe separation at aerodromes in Class G airspace pilots are required to exercise 'see and avoid' techniques supplemented by VHF monitoring and broadcasting procedures. These are designed to maintain traffic awareness and to self-administer circuit priorities, where appropriate, in the vicinity of such aerodromes. Discrete radio frequencies known as common traffic advisory frequencies [CTAFs] are assigned for use in those circumstances.Carriage of VHF radio is generally not mandatory — but highly recommended. However, there are some Class G aerodromes — usually those which have daily RPT movements — where the carriage and use of VHF radio, confirmed to be functioning on the CTAF, is mandatory for all aircraft (including ultralights) operating at that airfield. When operating at any non-controlled airfield, all radio-equipped (whether fixed installation or hand-held) aircraft, including ultralights, must make the standard broadcasts on the CTAF. Some non-controlled aerodromes may have a private ground-based Unicom communications operator. (Note that non-controlled aerodromes are now usually referred to as non-towered aerodromes.) The radio procedures required when operating in the vicinity of non-towered aerodromes are defined in the AIP Book section ENR 1.1 paragraphs 56–65 "Operations in Class G airspace". If operating at, or in the vicinity of, an airfield within Class G airspace that does not have a designated CTAF then standard radio procedures should still be used and the calls made on the default multicom frequency of 126.7 MHz. |
1.3 Restricted and danger areasSpecial use airspace, extending to varying heights, is defined on the charts used for air navigation. For safety reasons, flight into those defined special use areas may be prohibited (P), restricted (R) or marked 'danger' (D); the latter as a warning to take extra care if entering the area. Flight within a prohibited area is forbidden at all times but usually there are only temporary prohibited areas in Australia.Restricted areas are mostly military training and weapons firing ranges, which extend from a lower level (often the surface) to an upper level. Flight within those areas may be restricted at all times, or may be allowed at times when the restricted area is not activated. The charts show a reference number that refers to a detail entry in the Airservices publication 'En Route Supplement - Australia' [ERSA]. Details of the activation of restricted areas are promulgated by Airservices Australia in the form of NOTAM. Danger or alert areas usually relate to mining or quarrying sites, and to special aviation activities such as fixed training areas or aerobatic areas; it may be prudent to avoid such areas, but there is no restriction on entry. Other special use areas, for example those for hang-gliding or radio-controlled model aircraft flying, are also symbolically marked on aeronautical charts as a warning device, but there are no details available for these in any publication. Similarly, mines and quarries marked on charts, but not within a danger area, should only be overflown at a safe height to avoid blasting debris. |
1.4 AIP Book, ERSA and NOTAMAIP BookThe ICAO requires that the Aeronautical Information Service [AIS] of each member nation publish a standardised 'Aeronautical Information Publication' [AIP] that is included in a package of books, charts and other documents which together make up an 'Integrated Aeronautical Information Package' [IAIP]. The primary publication is the AIP Book, which contains longer-term operational reference information of rules and procedures written in plain language and covering civilian operations in Australian airspace.In the AIP Book, the term 'should' implies that users are encouraged to conform with the procedure, whereas the term 'must' (or 'shall') means that the procedure is mandatory and is supported by CARs or CAOs. Amendments are issued quarterly and supplements are issued monthly. It is not a vital document for the individual RA-Aus pilot certificate holder to have in print form — and it is an ongoing task to cope with the amendments — but each ultralight club and flight school should maintain an AIP Book print amendment subscription. AIP is essential for operations in controlled airspace. The three standard sections of the AIP Book are 'General' [GEN], 'En route' [ENR] and 'Aerodromes' [AD]. The subsections of most interest to recreational aviation are:
AIP Supplements [SUP] and Aeronautical Information Circulars [AIC]SUPs include operational information appropriate to the AIP. A SUP is published when the information is of a temporary nature and requires advanced notification such as planned military exercises that may close airspace to civil traffic. AICs contain information of a technical nature and are generally educational, giving advance notice of new facilities, services and proceduresEn Route SupplementThe AIP 'En Route Supplement Australia' [ERSA] is recommended to all pilots with a cross-country endorsement — it is an essential document for cross-country flight planning and operations. ERSA contains details of PRD areas, area weather forecast codes and weather report decodes, pre-flight and in-flight information services, navigation aids, and emergency procedures.Its main purpose is to provide, within the facilities [FAC] section, full physical details of all licensed aerodromes [ADs] with current updates relating to those aerodromes available via NOTAM. The aerodrome entry includes the VHF and HF frequencies used for air traffic services, self-announce broadcasts, flight information service, Unicom and automated weather information services. It also provides control tower operating hours and thus the times at which a Class D CTR reverts to non-controlled airspace. ERSA also lists limited detail of many unlicensed airfields — ALAs or 'Aircraft Landing Areas' is the official jargon — but NOTAM are not issued for ALAs. There is no information regarding recognised water alighting areas for seaplanes. Airservices Australia publishes online versions of the AIP Book, SUPS, AICs and ERSA at www.airservicesaustralia.com/publications/aip.asp (click the 'I agree' button to gain entry). To find a particular section of AIP or ERSA you have to click through a number of index pages. The section/subsection/paragraph numbering system was designed for a readily amendable looseleaf print document, so you may find it a little confusing as an online document. NOTAMNOTAM, derived from the old term 'notices to airmen', are issued by Airservices Australia and contain "information or instructions concerning the establishment, condition or change in any aeronautical facility, service, procedure or hazard, the timely knowledge of which is essential to persons concerned with flight operations." The NOTAM (current at the time) are available from the Airservices Australia online pilot briefing service, which we discuss in the 'route planning' module.The Australian Aircraft Owners and Pilots Association publishes biennially a very handy Airfield Directory, which has details of about 2000 airfields, including many that are not in ERSA. Contact information for the owners/operators is included but the communications and navigation aid frequencies shown may not be current. The cost is about $50. The Civil Aviation Safety Authority's VFR Flight Guide is recommended reading and a PDF version is included in the RA-Aus Members' CD. The PDF version of the VFR Flight Guide was downloadable from CASA's website but the existing edition was withdrawn in August 2009 and the new edition may not be available. Check the Airservices Australia Publications Centre for purchase or subscription details for the publications mentioned. The charts within AIP are detailed in section 2.3. |
1.5 VMC and the visual flight rulesThe two ICAO rule sets previously mentioned in section 1.1 are the Instrument Flight Rules [IFR] and the Visual Flight Rules [VFR]. Aircraft operating under the IFR are navigated by reference to cockpit instruments that process data received from ground stations or satellites. IFR flights may operate in both visual meteorological conditions [VMC] or instrument meteorological conditions [IMC] — see below. VFR flights may only operate in VMC.All national and international RPT jet flights into or between the major Australian cities would operate only in controlled airspace and under the IFR, but turbo-prop and piston-engined regional RPT aircraft, travelling to or from a smaller city, may operate some route sectors in Class G and under the VFR. Charter and business aircraft would tend to operate in both controlled airspace under the IFR or the VFR, and in Class G under the VFR. Agricultural aircraft would normally be operating in Class G and under the VFR, and may be encountered working at low levels close to airfields. General Aviation training aircraft would tend to operate in and out of a CTR or GAAP under the VFR. Military aircraft operate everywhere but particularly important to light aircraft are their low jet routes where they may be flying at very low levels using terrain-following radar. Beware: fast-flying camouflaged military aircraft may also be encountered at very low levels outside the designated low jet routes. Visual Meteorological ConditionsUltralight operations and non-instrument rated pilot operations may only be conducted in VMC.The visual meteorological conditions (minima) applicable below 10 000 feet amsl, and thus the VMC for ultralight and most light aircraft operations (take-off, en route and landing) are:
(The image above is courtesy of CASA's Flight Safety Australia, March–April 2002 issue) If operating in Class G airspace at or below 3000 feet amsl or 1000 feet agl, whichever is the higher, an ultralight or other aircraft may operate 'clear of cloud' but remain in sight of the ground — provided the aircraft is equipped with a serviceable VHF radio, the pilot has a radio endorsement, and the pilot listens out and transmits on the appropriate area frequency. Note that a non radio-equipped aeroplane can then only operate in conditions where the cloud base is 1000 feet above the flight level. Thus such an aircraft can only take off and land when the cloud base is 1000 feet higher than the circuit height, and the horizontal cloud clearance is at least 1500 metres. Even when there is no regulatory requirement, carrying VHF radio and continually maintaining a listening watch is highly recommended. Visual Flight RulesThe Visual Flight Rules applicable to ultralight operations and most light aircraft operations are primarily 'see and avoid' other traffic, plus the following specifics:
VFR 'on top'In addition, an aircraft cannot be operated on top of cloud that is more extensive than scattered, unless it is fitted with serviceable flight and navigation instruments as specified in CAO 20.18 Appendix IV — which includes an artificial horizon and directional gyro. Other restrictions apply — see AIP ENR 1.1 paragraph 19.2. Taking all into account, it is probably unwise for an ultralight aircraft to operate above any cloud cover. See adverse weather.Quiz question"You are at an airfield (elevation 2700 feet and situated in flat terrain) and the base of an extensive layer of stratocumulus has been confirmed as 4000 feet amsl but visibility exceeds 10 km. Can you legally take off in an ultralight and depart the airfield?"Ultralight operations (or any flight operation where the pilot in command [PIC] does not hold a night VFR rating or Command Instrument Rating) may only be conducted in VMC and flight below 500 feet agl is forbidden except when taking off or descending to land. The visual meteorological conditions applicable below 10 000 feet amsl, and thus the VMC for ultralight operations (take-off, en route and landing) are:
Thus take-off for an ultralight that is not equipped with a serviceable radio would not be legal. The minimum altitude that a non-radio flight could be undertaken is 3200 feet amsl (2700 feet elevation plus 500 feet agl), and the vertical cloud clearance is then only 800 feet. However, a radio-equipped aircraft would be legal, provided operations were conducted between 500 and 1000 feet agl, thus 'clear of cloud'. The rationale for this is that radio provides the ability to alert other aircraft — possibly operating in the same restricted flight conditions — to your presence. VFR cruising altitudesFlights operating in Class G under the VFR must fly at cruising altitudes selected in accordance with the table below when at a height above 5000 feet amsl and, whenever practicable, should be operated at such altitudes when below 5000 feet. The cruising altitudes for aircraft operating under the IFR are in 1000 feet steps; thus 5000 feet amsl is an IFR cruising level and not available to VFR aircraft. Operating in accordance with the cruising altitudes does improve safety, but pilots should be aware that the risk of collision still exists; for example, consider an aircraft tracking 175°, while to the south another aircraft is tracking 005° at the same correct altitude. Those two aircraft could well be closing on a collision course.
Note: there are no cruising levels available in the transition layer so VFR aircraft must not use 10 500 feet (FL105), and 11 500 feet (FL115) is not available if area QNH is below 997 hPa. Flight at the control area boundaryAIP ENR 1.4 paragraph 1.1.7 states: "When ATS airspaces adjoin vertically (one above the other), flights at the common level must comply with the requirements of, and will be given services applicable to, the less restrictive airspace." In this context Class G is the least restrictive airspace, followed by Class E, Class D, Class C and finally Class A as the most restrictive.Thus if the lower limit of a Class C control area step was 5500 feet with Class G below, a VFR aircraft could legitimately cruise at 5500 feet in that area without requiring ATC clearance — provided of course that height keeping is good, the altimeter is very accurate and the correct QNH is set. Air traffic controllers keep aircraft at 500 feet plus above the lower level of the controlled airspace to provide clearance from Class G traffic. However, be aware that the wake turbulence from heavy aircraft sinks and drifts downwind. Also there is a problem with selecting which QNH altimeter setting to choose. So, taking everything into account, it is not a good idea to fly at the airspace intersection level. |
1.6 Ultralight flight operationsRA-Aus registered ultralight aircraft must operate in VMC and in Class G or Class E, except with special permission (see below) to operate within a Class C, D or GAAP control zone — such permissions are usually applied on a long-term basis and only to pilots who also hold a valid pilot licence plus the RA-Aus Pilot Certificate.
Ultralight operations in Class C, D and GAAP control zonesTo operate in Class C, D and GAAP control zones, the ultralight aircraft and the engine must either be certificated to the design standards specified in CAO 101.55 para 6.1 or meet criteria specified elsewhere (see paragraph 5.2 in both CAO 95.32 and CAO 95.55); be fitted with a certificated or CASA-approved engine and CASA-approved (rather than ACMA-approved) radio equipment; and the pilot in command must hold a valid Pilot Licence ( i.e. Private Pilot Licence — PPL, Commercial Pilot Licence — CPL, Air Transport Pilot Licence — ATPL) in addition to the Pilot Certificate. Even so, it is unlikely that, if it came to a judicial test, an ultralight would be legally be able to operate from, or enter, a GAAP as the 'lanes of entry' to such airfields usually involve overflight of built-up areas, and overlying controlled airspace may severely limit available altitude (and thus gliding distance) in such lanes. CAO 95.10 aircraft must not be operated in Class C, D and GAAP control zones.A transponder must be operated in Class C CTRs and CTAs. Ultralights must comply with the flight conditions specified in the relevant CAO (95.10, 95.32 or 95.55). For example section 5 of both CAO 95.10 and CAO 95.55 forbids flight below 500 feet agl and flight over cities and towns at a height from which it cannot glide clear of all dwellings, buildings and persons within the built-up area. Be mindful that it is the legal responsibility of the pilot, not the ATS personnel, to ensure compliance with CAO 95.55 and other regulations. Air traffic controllers presume that the pilot of an aircraft requesting entry into their airspace is legally, medically and practically qualified to do so and a subsequent airways clearance does not absolve the pilot of legal responsibility. Also bear in mind that the entities owning Class C, D and GAAP aerodromes (and others) may publish their own 'conditions of use' which users should be aware of, and comply with. Quiz question"You are a prudent ultralight pilot planning a two-hour flight to an airfield due east of you on a mild day with light easterly winds at levels up to 10 000 feet and clear skies. The terrain is open country at an elevation of about 800–1000 feet all the way with scattered minor hills. What altitude would you cruise at?An aircraft operating under the Visual Flight Rules, and below 5000 feet amsl (area QNH), may cruise at any safe altitude. However, a prudent ultralight pilot undertaking a two-hour flight would choose a hemispherical VFR cruising altitude whenever practicable. For any aircraft heading with an easterly component, the VFR cruising altitudes are 1500 and 3500 feet. The ultralight flight could operate at a level above 5000 feet if safety considerations dictated so. Then the pilot could choose one of the three mandatory easterly cruising altitudes below 10 000 feet — 5500, 7500 or 9500 feet. However, this flight over open terrain in clear conditions would not warrant an ultralight intrusion above 5000 feet, thus the only practicable cruising level available to a prudent pilot is 3500 feet, about 2500 feet above the general terrain. |
1.7 Communication and navigation aidsCivil aviation radio communications are conducted primarily in the aviation very high frequency [VHF] communications [COMM] band, 118.00 to 136.975 MHz, where, at 0.025 MHz steps, there are 760 channels possible. In the less accessible areas of Australia, where there is no VHF ground coverage, communications must be in the various high frequency [HF] network bands between 3400 and 9500 kHz. The PCA shows VHF coverage (but not FIA boundaries or frequencies) and the appropriate short-wave frequencies in the three domestic HF network areas. Military aircraft primarily use UHF communications.There is an inter-pilot air-to-air communications frequency available at 123.45 MHz. More information on frequency allocation for club, sport aviation and other aviation activities is contained in the aircraft station operating frequencies section of the VHF Radiocommunications Guide. In Australia, the VHF Omni-directional Radio Range [VOR] primary air route, homing and position-fixing navigation aids operate in the 112.1 to 117.975 MHz aviation VHF navigation [NAV] band. The Instrument Landing System runway localisers at larger airports operate in the 108.00 to 112.00 MHz VHF NAV band. Thus the aviation VHF NAV/COMM band is from 108.00 to 136.975 MHz, with some 200 channels (at 0.05 MHz intervals) in the NAV band and 760 in the COMM band. Some hand-held airband COMM transceivers have a very limited VOR receiver capability, but the full NAV/COMM capability is confined to more expensive panel-mounted transceivers/VOR receivers/VOR indicators coupled to a VOR antenna. Non-directional aviation radio beacons [NDBs], installed to provide a homing facility for smaller aircraft, transmit in medium wave bands between 190 and 535 kHz. The companion airborne automatic direction finding receivers [ADFs] can also pick up transmissions in the 520 to 1611 kHz AM broadcast band, depending on the power output of the radio station. The broadcasting frequency, latitude and longitude, power output in kW and the height of the mast agl (quite a few are over 600 feet agl and situated on the high ground) for all AM broadcast stations, is contained in the ERSA NAV/COMM section. The location of some AM broadcast stations' transmitter masts is shown on World Aeronautical Charts [WACs], with the station identification but not the frequency. Most licensed aerodromes have an NDB and many would have a VOR. |
1.8 Distress frequencies and AusSARWhen a pilot is experiencing in-flight difficulties, it is advisable to inform others as early as practical and to advise whether the pilot considers the situation to be an emergency or something less. The frequency on which a distress call (a MAYDAY transmission) or an urgency message (a PAN-PAN transmission) is made should be that which is likely to provide a quick response: for example, if other aircraft are known to be using a local CTAF, use that — otherwise use the area frequency.If a registered civil or ultralight aircraft crashes away from a controlled aerodrome or is reported missing, Australian Search and Rescue [AusSAR] has national responsibility for coordinating the search and rescue. More information is contained in the safety and emergency procedures module of the 'Coping with Emergencies Guide'. |
Groundschool — Flight Planning & Navigation Guide
| Guide content | [1. Australian airspace regulations] | 2. Charts & compass | 3. Route planning |
| 4. Effect of wind | 5. Flight plan completion | 6. Safety audit | 7. Airmanship & flight discipline |
| 8. En route adjustments | 9. Supplementary navigation techniques | 10. Global Positioning System |
| 11. Using the ADF | 12. Electronic planning & navigation | 13. ADS-B surveillance technology |
Supplementary documents
| Operations at non-controlled airfields | Safety during take-off & landing |
 Section 2 of the Flight Planning & Navigation Guide discusses Australian navigation charts and the aircraft compass
|
Copyright © 2001–2009 John Brandon [contact information]
