Definition
An ATC radar display mode in which the controller's scope shows a composite picture built from multiple radar sites, rather than the feed from a single radar. The display is automatically assembled from whichever radars provide the best coverage of each part of the airspace, giving the controller broader and more reliable surveillance than any one radar could provide alone.
Plain English
The controller's screen is showing a stitched-together picture made from several radars at once, not just one. The system blends the feeds so the controller sees the best available track of each aircraft.
Context Anchor
Seen in FAA glossary and ATC surveillance discussions, especially when describing how a controller’s display receives and combines aircraft position information.
Derivation
Mosaic comes from the Latin musaicum, meaning a picture made up of many small pieces fitted together. That captures it exactly -- the controller's display is one picture assembled from many radar sources.
Why Pilots Care
Gives continuous coverage across wide areas where individual radars have range or terrain limits, helping with weather avoidance and traffic awareness.
Analogy
Like a map app using more than one signal to decide where you are, this mode combines several inputs into one displayed position.
Intuition Check
Do not read “mosaic” here as a cockpit weather picture or a pilot-selected display setting. In this term, it means ATC is combining several surveillance inputs into one controller display picture.
Example Sentence 1
While operating in mosaic/multi sensor mode, the controller's display was drawing position data from three different radar sites covering the sector.
Example Sentence 2
In multi-sensor mode the display merged ground radar and ADS-B traffic into one smooth picture.