Definition
Selectable categories of information that can be turned on or off in an electronic chart or moving-map display, allowing the pilot to show or hide specific data such as airspace boundaries, special use airspace, terrain, weather, airways, or airport details.
Plain English
On a digital map, you can switch different kinds of information on or off. Each switchable category — terrain, airspace, weather, and so on — is a layer.
Context Anchor
Seen in tablet flight apps, panel map displays, and planning tools when a pilot chooses what information to show before or during a flight.
Why Pilots Care
Enables pilots to declutter the display and focus on relevant airspace or terrain data, reducing the chance of overlooking special use airspace restrictions during flight planning or en route.
Analogy
Map layers are like clear sheets placed over a paper chart. One sheet might show airspace, another might show weather, and another might show terrain; you choose which sheets to view.
Intuition Check
Do not assume a map layer is a separate map. It is information added to, or removed from, the map display.
Example Sentence 1
Before departure, she enabled the special use airspace and TFR map layers to confirm her route stayed clear of any active restrictions.
Example Sentence 2
With terrain and obstacle map layers active, the display highlighted elevation changes along the approach path.