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Practice Exam

Danger, Restricted and Prohibited Areas

Danger, restricted, and prohibited areas are shown on the chart as an area with a red line outline and red hatching across the area. The outline is:

Solid red when the area is active permanently or only during scheduled times
Dashed red when the area is activated by NOTAM

Every danger, restricted, and prohibited area is given a unique number. This is written next to the area on the chart, along with the vertical limits of the area. For example:

D139/1.5 is Danger Area 139, located to the north of Southend. The “1.5” denotes that it extends up to 1500ft AMSL and “OCNL/2.0” denotes that it occasionally extends up to 2000ft AMSL. A NOTAM is published when the higher limit applies.
R217/2.0 is Restricted Area 217, located around the Sizewell power station on the Suffolk coast. The “2.0” denotes that it extends from the surface to 2,000ft AMSL.

A list of these areas and associated information (and usually a contact phone number for coordination) is found in the AIP ENR 5.1. Click here to view the UK AIP.

Other Danger, Restricted & Prohibited Area Symbols

UNL
UNL means unlimited – the area extends upwards indefinitely.
§
This ‘double S’ symbol denotes that a Danger Area Activity Information Service (DAAIS) is available. The frequency to contact while airborne is in the chart legend.
*
The asterisk symbol denotes airspace which is subject to byelaws that prohibit entry during periods of activity

This cross indicates that a Danger Area Crossing Service (DACS) is available