Special Use Airspace (SUA)

Special use airspace exists to keep incompatible activities apart. Some of it constrains the activity within — for example confining military exercises or hazardous operations to a defined volume — while some constrains other aircraft from entering. The principal ICAO categories are prohibited areas, where flight is forbidden outright; restricted areas, where flight is allowed only under stated conditions or with authorisation; and danger areas, which warn that hazardous activity may be taking place. National systems add further designations such as military operating areas and alert or warning areas.

Each special use area is published with a designator, lateral boundaries, vertical limits and, where relevant, times of activity, since some areas are active only at certain hours or by notification. Understanding which designation applies matters operationally: a danger area is a warning rather than a prohibition, whereas entering an active prohibited or restricted area without authorisation can have legal or safety consequences.

Distinguishing the various special use designations along a route is part of assessing where access is constrained or hazardous. AeroVigil frames airspace restrictions alongside conflict and interference signals so operators can see both standing special use airspace and newly emerging constraints together.