9.4 Restricted, Danger and Prohibited Areas and Obstacles

Special-Use Airspace on Visual Charts

On top of the airspace-class layer, Australian visual charts overlay special-use airspace: restricted areas, danger areas, and prohibited areas. Each is drawn with a distinct pattern and carries an identifier and activation information. For an RPA pilot, the practical question is always: can I operate here, and is it active right now? The chart answers the first question; the NOTAM system answers the second.

Restricted Areas — RA1, RA2, RA3

Restricted areas are designated where activities (such as military flying, weapons ranges, or specialised operations) make uncontrolled access hazardous. They are tiered:

• RA1 — lowest tier. Operations may be permitted subject to conditions printed on the chart or in the AIP.
• RA2 — middle tier. Greater restriction; entry generally requires approval from the controlling authority.
• RA3 — highest tier. An RPA may not operate in an RA3 area without the required approval. Treat RA3 as closed unless you hold the relevant approval from the controlling authority.

The tier is printed as part of the area identifier on the chart (for example, a labelled restricted area annotated RA3). Always read the activation conditions associated with the area. The controlling authority (often Defence or a range operator) is the body that can grant approval to operate within an active RA3 area; for a RePL holder without a ReOC, that approval is not realistically available, so RA3 is effectively a no-fly area.

Danger Areas

Danger areas are marked where activities could be hazardous to aircraft (for example, blasting sites, firing ranges, or aerobatic practice). They are not outright no-fly zones — the guidance is to exercise caution and, where applicable, to contact the controlling authority. For RPA operations, treat a danger area as a location requiring enhanced care, an active NOTAM check, and consideration of whether transit is prudent. If the activity is active (often promulgated by NOTAM), consider delaying the flight or rerouting around the area.

Prohibited Areas

Prohibited areas are the strictest category: no entry under any circumstances. They are drawn with a distinct symbol and a "P" identifier. An RPA must not operate within a prohibited area at any time, regardless of altitude or approval. Unlike restricted areas, there is no approval pathway — the prohibition is absolute.

Conditional and Intermittent Activation

A key trap: many restricted areas are conditional or intermittent. The chart shows their geographic extent and tier, but not whether they are active at the moment of your flight. Activation can be:

• Permanent — active continuously, with no time window.
• Conditional — active only during published conditions (for example, daylight hours, weekdays only, or when a NOTAM is in force). The chart annotation or AIP entry states the condition.
• Intermittent — activated by NOTAM for specific periods (for example, a range exercise between 0900 and 1200 local on a given date).

Some restricted areas carry published activation times in the AIP or on the chart margin (for example, "ACT Mon–Fri 0800–1700 local"). Others are activated purely by NOTAM. Always treat the charted times as a guide and confirm with a NOTAM check.

The Activation-Check Workflow (NAIPS)

Before any flight touching or near a restricted area, check the current activation via NOTAMs through NAIPS (the Airservices National Aeronautical Information Processing System). The workflow is:

1. Identify the restricted-area identifiers (e.g., R###, RA3) over and around your operating site from the VTC or VNC.
2. Open NAIPS and run a briefing request covering the operating area and a sensible radius (typically 10 NM or more, to catch nearby areas).
3. Set the time window to cover the planned flight plus a margin either side.
4. Read every returned NOTAM that mentions one of your identifiers. Note the activation window, the vertical limits (some restricted areas have lower limits above the surface — confirm the lower limit against your operating height), and any conditions.
5. If a restricted area is listed as active during your window, treat it as closed unless you hold the relevant approval. If it is inactive, record the NOTAM serial number as evidence of the check.

A charted restricted area that is inactive at the time of flight may still be flyable, but only if the activation status is confirmed in NAIPS. "The chart shows it" is not permission; "the NOTAM confirms it is inactive" is.

Worked Scenario: Flying Near a Restricted Area

You plan a mapping flight 2 NM from a charted RA2 area annotated "ACT by NOTAM". The chart shows the area's lateral boundary and an upper limit of 4,500 ft AMSL, with a lower limit of the surface. Your operating site is outside the boundary, so the question is not entry but proximity. You run a NAIPS briefing for a 10 NM radius and your flight time. Two outcomes:

• No activating NOTAM — the area is inactive for your window; proceed, but keep clear of the boundary and monitor CTAF for any traffic transiting the area.
• An activating NOTAM is present — the area is active. Because you are outside the boundary, the activation does not by itself bar your flight, but it does mean military or other traffic may be operating nearby. Increase lateral separation, consider rescheduling if the activity profile conflicts with your operation, and record the NOTAM serial.

If your operating site were inside the RA2 boundary, an activating NOTAM would bar the flight unless you held controlling-authority approval; an inactive status would let you proceed, subject to the standard conditions.

Charted Obstacles

Visual charts also mark obstacles relevant to low-level RPA operations:

• Towers and masts — shown with a dedicated symbol and an elevation in feet AMSL. The elevation is the top of the structure.
• Powerlines — shown as lines; grouped crossings may carry a grouped elevation. Powerlines are a particular hazard for RPA because the wire is hard to see and can span valleys well below the surrounding terrain.
• Other structures — where obstacle density is high, obstacles may be grouped with a maximum elevation figure for the group.
• Obstacle lighting — lit obstacles carry a light symbol. Note that lighting does not change the elevation; an unlit obstacle at the same height is just as lethal. Do not assume an obstacle is unlit just because no light symbol appears — check the latest NOTAM for lighting status, as lights can fail.

Terrain and Powerline Hazards

Two terrain-related hazards deserve attention. First, a powerline spanning a valley may be charted at the elevation of its highest support tower, while the wire between towers sags below that elevation but still well above the valley floor — your RPA may be below the charted obstacle elevation and still hit the wire. Keep a wide lateral margin from powerline crossings. Second, rising terrain can reduce your AGL clearance without any change in your RPA's AMSL altitude: if you fly from 600 ft terrain toward 900 ft terrain at a fixed 1,000 ft AMSL, your AGL height drops from 400 ft to 100 ft. Plan routes that account for terrain rise, not just the launch-point elevation.

For RPA planning, obstacles matter in two ways:

1. Collision avoidance — keep laterally clear of towers and masts, especially when operating at or near 120 m (400 ft) AGL, where many towers sit.
2. Height awareness — an obstacle elevation printed in AMSL can be converted to AGL by subtracting the charted terrain elevation, giving the obstacle's height above the surrounding ground.

Habit: when a charted obstacle lies near your operating area, note its AMSL elevation, lighting status, and lateral position in your pre-flight plan, and keep clear by a safe margin. Re-check obstacle status by NOTAM — new temporary obstacles such as cranes are promulgated by NOTAM and will not appear on your chart.