An important note: the semicircular rule (aircraft flying with a track between 0° and 179° must be at an odd flight level, aircraft flying with a track between 180° and 359° must be at an even flight level) is different in Italy, because the main flight routes are north/southbound! Therefore:
- aircraft having a track between 270° and 089° (northbound) must fly at an even level;
- aircraft having a track between 90° and 269° (southbound) must fly at an odd level.