Warning area

Warning area is airspace that extends from three nautical miles off the coast of the United States and warns pilots about potentially hazardous activity. A warning area is outside domestic territory, so the United States cannot apply the same regulatory control as it does over domestic special use airspace.

What it governs

Warning areas are identified on charts by a designation and number, such as W-XXXX. Activities can include military exercises, weapons testing, or other operations that may create a hazard for aircraft. The area warns pilots to obtain information, remain alert, and plan an appropriate route.

A warning area is different from a restricted area, which may limit entry in domestic airspace, and a prohibited area, which protects a location by prohibiting flight. The chart legend and current notice determine the practical details.

Example

A pilot planning a coastal flight sees a warning area along the route. The pilot checks the current chart and available activity information, considers remaining outside the area, and maintains communication as appropriate. The charted boundary does not guarantee that hazardous activity is absent outside it.

Why it matters

Warning areas can contain fast-moving aircraft, surface vessels, or other hazards that are difficult to detect visually. Route planning should account for the activity, weather, fuel, and available avoidance options rather than treating the area as an ordinary empty space.

Review current charts, notices, and the FAA Aeronautical Information Manual before flight. This page does not provide current activity status.

Related terms and tools

• Restricted area
• Prohibited area
• FAA airspace resources