Restricted airspace is a designated area in the sky where aircraft are not allowed to fly without special permission. This type of airspace is often established for safety reasons, such as military operations, or to protect sensitive locations like nuclear power plants or government buildings. Pilots must be aware of restricted airspace when planning their flights. They can find information about these areas on aeronautical charts, which show where restrictions are in place. Violating these restrictions can lead to serious consequences, including fines or legal action.