General Class D operations

Introduction

These recommended procedures apply at class D airports located in various capital cities (former 'GAAP' airports) and regional class D airports such as Tamworth. On 3 June 2010, there were changes to the airspace associated with the six existing general aviation aerodrome procedures (GAAP) locations. These changes involved adopting the International Civil Aviation Organization’s (ICAO) class D airspace classification, along with procedures broadly aligned with those of the American Federal Aviation Administration (FAA).

Replacing the Australian-specific GAAP with the internationally recognised class D procedures is a step towards standardising Australian aviation procedures with international practices. In order to increase safety through standardisation, the new class D procedures at the former GAAP aerodromes now also apply in all class D control zones and class D controlled airspace.

Australia has adopted FAA class D procedures such as abbreviated clearances and distances from cloud, including:

[Although under the new rules you no longer have to proceed VFR within a class D control zone, IFR pilots are encouraged to proceed VFR whenever possible and to advise ATC. Such action will remove delays that might be caused by separation requirements for IFR flights within the control zone and adjoining airspace.]

Entering class D

Entry points

You can enter a class D control zone from any direction. There is no mandatory requirement to enter via a VFR approach point. However, if circumstances allow, you should enter via one of the VFR approach points, which are marked on the visual terminal charts with a shaded diamond. This is recommended because they:

The VFR approach points are selected because they are prominent landmarks which help with visual navigation and make it easier for ATC to segregate traffic.

ATC may still exercise the right to instruct you to enter class D airspace via a particular point.

Clearances

You must obtain a clearance before operating in a class D control zone. This could be a clearance to take off, instructions for circuit entry, or a clearance to transit the control zone. An implied clearance is in place when two-way communications with the tower has been established, as described below.

Individual clearances are required for:

  1. Take-off and landing
  2. Entering, crossing or taxiing along all runways. Note: An instruction to ‘Hold short of runway … [number] left [or centre or right]’ requires you to hold at a marked holding point.
  3. Turns in a direction contrary to the circuit for a particular runway. Note: An ATC circuit entry instruction acts as a clearance for a turn contrary to normal circuit direction, if the contrary turn is required to comply with the instruction.
  4. Circuits at a height other than 1,000ft
  5. Operations on routes or at altitudes different from those published in ERSA.

Establishing two-way communications

When an aircraft contacts ATC at a class D aerodrome and provides sufficient information about track, position, level, and intentions, ATC may give a clearance to enter the airspace by simply acknowledging the transmission with the aircraft’s callsign. Alternatively, a clearance may be denied, or afforded by an alternate route or level as instructed by ATC. Such instructions may include ‘join crosswind’, ‘overfly’, or ‘report at [position]’. The acknowledgment authorises the aircraft to enter the class D airspace following the stated track and level, or any alternative instruction given by ATC. Pilots are then required to maintain two-way communications with ATC and comply with any subsequent ATC instructions.

This shortened procedure does not eliminate the availability of a ‘traditional’ airways clearance. However, it provides an abbreviated clearance option for use when both pilot and ATC understand the proposed course of action.

Readback requirements

You must read back:

Pilot responsibilities

When operating in class D airspace, you must:

  1. Sight and maintain separation from other aircraft
  2. Comply with ATC instructions, while ensuring you maintain visual separation from other aircraft
  3. Immediately advise ATC if unable to comply with an ATC instruction
  4. Advise ATC if unable to sight, or if you lose sight of, other aircraft notified as traffic.

VMC in class D airspace

IFR flight in class D airspace

Unlike the old 'GAAP' aerodromes, an IFR flight is not required to operate under VFR within a class D control zone if VMC exists. However, IFR pilots are encouraged to proceed VFR whenever possible, and to advise ATC. Such action will remove delays that might be caused by separation requirements for IFR flights within the zone and adjoining airspace.

Special VFR (SVFR)

If a VFR flight is unable to maintain VMC when entering or operating within a class D control zone, you can request a Special VFR clearance. A Special VFR clearance may be available in certain circumstances to recover an inbound aircraft that suddenly encounters reduced visibility (as low as 1600m) due to a rain shower, for instance. However, it will not apply to the conduct of circuits in less than VMC, or for a departure in less than VMC. Remember that the visibility required for operations in class G airspace is still 5000m!

Separation requirements for SVFR flights differ depending on whether the cause of the SVFR clearance is reduced visibility or low cloud. Under class D rules, SVFR flights will be separated from IFR flights at all times, and SVFR will be separated from other SVFR flights when low visibility is the cause.

SVFR is only available by day and cannot be initiated by ATC. A SVFR clearance will only be given in response to a ‘request special VFR’ by the pilot. Be sure to advise the tower of the reason for your request ̶ either low cloud or poor visibility. Your request must be coordinated with ATC to ensure that appropriate separation is applied to all flights.

There will generally be no specific tracking instruction given with a SVFR clearance because the pilot must be able to manoeuvre the aircraft around cloud in accordance with the SVFR criteria. Similarly, an altitude may not be given, although there is always the option available to ATC to assign an altitude such as ‘not above 1500’.

A special VFR clearance only applies within the class D control zone.

When operating under a special VFR clearance, you are responsible for ensuring that:

Maximum speed within class D airspace

All flights in class D airspace are limited to 250KIAS unless the pilot informs ATC that a higher minimum speed is required for safety reasons. All flights in class D airspace within 4nm and 2500ft above aerodrome level are limited to 200KIAS unless ATC approves otherwise.

Separation

In class D airspace, ATC will provide the following air traffic services to aircraft:

All pilots must maintain a vigilant lookout for other aircraft at all times.

Under the new procedures, if you are flying VFR, you are entirely responsible for avoiding the wake turbulence from heavier aircraft, including when you are landing. The same applies if you are flying IFR and you accept responsibility for following, or maintaining separation from, a heavier aircraft. In these circumstances, ATC assistance will be limited to issuing a wake turbulence caution.

Surface movement control (SMC)

SMC has been re-introduced at the former GAAP aerodromes and is now provided at ALL controlled aerodromes.

On initial taxi

Before taxiing or contacting SMC, check that your radio receiver is functioning correctly and obtain the current ATIS. The preferred method for checking your radio is to monitor the ATIS.

When ready to taxi, make a taxi call to SMC including the following details:

  1. aircraft type and callsign
  2. number of POB (not required for VFR flights)
  3. identification of ATIS code received
  4. location on aerodrome
  5. flight rules (not required for VFR flights)
  6. intentions (crosswind circuit training, first intended landing point etc.)
  7. for training flights, whether dual or solo
  8. ‘request taxi’.

If an airways clearance is required you should make your request to SMC when ATC is operating, or to the appropriate ATC centre when the control zone is deactivated.

To minimise delays on departure, you should notify flight details using the national aeronautical information processing system (NAIPS) as the preferred option. You can also telephone, fax or, as a last resort, radio SMC.

Where possible, you should carry out your pre-take-off checks in a run-up bay. A taxi clearance to a particular runway holding point entitles you to conduct your pre-take-off checks using an enroute run-up bay.

Never enter or cross a runway en route to the holding point or run-up bay unless specifically cleared to do so by ATC. When vacating a holding bay, you must give way to aircraft on the taxiway.

Ready for take-off

When you are ready for departure and first in line at the holding point, select the relevant tower frequency, and report:

For example: ‘ABC, Ready runway [Left/Centre/Right] for [Upwind/Crosswind/Downwind] departure.’

After landing

Before you land, plan your taxi route to your parking position. After landing, vacate the runway as soon as practicable. Remember that aircraft on a taxiway must give way to aircraft vacating a runway.

If you have landed on a runway that intersects another runway, you may cross the intersecting runway, but you must not vacate onto the intersecting runway unless ATC has cleared you to do so.

After vacating a runway, you must not enter, re-enter, cross or taxi along any runway unless ATC has given you a clearance to do so. On vacating the runway, contact SMC and advise intentions or destination on the aerodrome.

Flying in the circuit

ATC may issue a sequencing instruction with a take-off or touch-and-go clearance. When issued with a sequencing instruction, you must follow the aircraft you have been sequenced to follow.

Unless otherwise instructed by ATC, you must report downwind when starting the downwind leg. This report should include aircraft type, callsign, ‘downwind’ and intentions [full-stop or touch-and-go]. If there is too much radio traffic for the call to be made in this position, report mid-downwind or late-downwind as appropriate. ATC will issue a sequencing instruction based on your position in the circuit.

If you wish to conduct a non-standard circuit, such as a glide or flapless approach, advise the tower with your downwind report. This advice will also alert other circuit traffic.

You must get tower approval before conducting simulated engine failure training. (Note: local aerodrome procedures may preclude such operations). You must also obtain tower approval before conducting simulated engine failure training in a multi-engine aircraft within 5nm of a controlled aerodrome.

When sequencing aircraft, ATC will indicate the position of the preceding aircraft by reference to a leg of the circuit or as a clock bearing, and describe it either as a specific type or in general terms (e.g. Cessna or twin). Unless ATC instructs otherwise your SSR transponder should be turned to ON/ALT code 3000.

ATC may issue a sequence number. Sequence numbers specify the position of an aircraft with respect to any preceding aircraft.

The instruction ‘follow’ requires you to sight the preceding aircraft and regulate your speed and approach path to maintain a safe distance from that aircraft. If you cannot see and identify the preceding aircraft you must advise ATC.

A landing clearance does not diminish your responsibility to maintain sufficient separation from the preceding aircraft during landing.

Inbound call

You must establish and maintain two-way communications with ATC before entering class D airspace from class G airspace.

You should make your inbound call approaching the relevant VFR approach point. Alternatively, you may establish initial contact with ATC at eight to 10nm from the aerodrome.

Your inbound call should include: type, callsign, position, level, ATIS code received, and intentions (for example, ‘inbound’).

You should squawk code 3000 and ALT just prior to contacting the tower with your inbound call.

Departures

Into class G airspace

When departing the control zone into class G airspace, you should do so on upwind, crosswind or downwind by extending the relevant leg of the circuit and then tracking clear of VFR approach points and associated routes.

As a VFR flight, you do not need to make a departure call when departing class D airspace into class G airspace. Nor do you need to request approval to change frequency when transiting from class D airspace into class G airspace.

Into class C airspace

If you are departing directly into class C airspace, the airways and departure clearances issued by ATC will authorise you to operate in both class D and class C airspace.

Transit of class D airspace

If you intend to transit through class D airspace from class G airspace without landing, it is recommended that you plan to do so via a VFR approach point.

You must establish two-way communications with ATC before reaching the class D airspace boundary, so you should make your call approaching the relevant VFR approach point. Alternatively, you may establish initial contact with the tower when you are around eight to 10nm from the aerodrome.

Your call should include: type, callsign, position, level, ATIS code received and intentions (for example, ‘overflying for [next tracking point]’).

Flight near class D airspace

When you are flying in class G airspace near a class D airspace boundary, you should monitor the tower frequency to make you aware of traffic entering and leaving that airspace.

Licensing

A private pilot licence holder with a logbook entry to fly an aircraft as pilot in command (PIC) in a control zone at a GAAP aerodrome may now fly an aircraft as PIC in class D non-radar airspace, including a class D control zone which has no radar service.

DISCLAIMER

This information is a brief outline of the practices and procedures at class D aerodromes and is designed to provide insight into the general philosophy behind the procedures. This information is not necessarily definitive and should never be used operationally without first cross-referencing with all appropriate documentation.