Uncontrolled Airspace

IFR

Taxi

Prior to, or during, taxiing at an uncontrolled aerodrome, IFR aircraft should establish two-way communication with ATS. This commences the SARWATCH service.

If unexpected delays prevent a departure within approximately 10 minutes from establishing the SARWATCH service, pilots should inform ATS. In response, ATC may decide to set an Ops Normal Time.

At uncontrolled aerodromes with low overlying CTA, expect to receive an airways clearance prior to departure.

Radio setup is obviously a pilot preference but it is recommended that pilots monitor the ATC frequency on COM1 and the CTAF/Advisory frequency on COM2.

Departure

After taking off and setting course for your first tracking point, inform ATC of your departure. If you haven't already received an airways clearance, ensure that you stop your climb below the base of CTA.

Tip

The CTA lower levels are displayed on ERCs and TACs.

In response, ATC will provide an airways clearance (where available), if not already issued.

Cruise

When cruising below the transition layer, the aircraft altimeter should be set to area QNH (or a more appropriate QNH source). When cruising above the transition layer, the altimeter should be set to the standard altimeter setting (1013 hPa or 29.92 inHg).

Track/Level Changes

When established outside of controlled airspace, there is no requirement for authorisation to change your flightpath. However, you must obtain traffic information on any change you will shortly commence, to ensure that doing so doesn't cause conflict with other aircraft.

Arrival

Aircraft in CTA must obtain a clearance to leave CTA on descent. Aircraft cruising OCTA should obtain traffic information prior to commencing descent. Pilots must inform ATC prior to altering track to commence an approach or arrival procedure.

ATC will provide a traffic statement for any conflicting aircraft which may impact the arrival. Pilots should communicate with any conflicting aircraft on the CTAF/Advisory frequency. There is no minimum separation required between aircraft outside controlled airspace, but it is recommended that pilots adjust their flightpath to maintain at least 1,000ft vertically and 5nm horizontally between aircraft. It may be necessary to adjust the aircraft's speed or track to alter the ETA of the aircraft, where the natural ETA conflicts with another aircraft.

Pilots may choose to conduct a visual approach or an instrument approach, depending on the weather conditions, time of day, and traffic situation. After arrival at the destination aerodrome, pilots must cancel their SARWATCH, which will close their flight plan and cease all services with ATS. If VHF radio reception is unsuitable on the ground, SARWATCH should be cancelled before VHF coverage is lost. Alternatively, pilots may choose to use text-based communication to cancel the service on the ground.

VFR

Flight Following

Flight Following provides VFR aircraft with the same surveillance service afforded to IFR aircraft outside controlled airspace. It is only available outside controlled airspace, within surveillance coverage, and is subject to controller workload.

Pilots should request the service from the overlying ATS unit. After the service has been commenced, any changes to an aircraft's track or level should first be communicated as per Track/Level Changes.

Changing Flight Rules

The flight rules of a particular flight are generally communicated through the flight plan. However, there are situations where it may be beneficial to change flight rules during the flight.

Pilots may wish to upgrade from VFR to IFR due to poor weather conditions. Pilots may also wish to downgrade from IFR to VFR in VMC, where they wish to continue without the oversight of an information service from ATS. Operating VFR may also allow aircraft to depart from busy aerodromes where an IFR departure is not available due to traffic congestion.

In either case, pilots must communicate their intent to change flight rules with the relevant ATS unit.