Definition
A radar system that refreshes its display of aircraft position significantly faster than standard air traffic control radar, typically updating once per second or faster rather than every several seconds. High-update radar is required for Precision Runway Monitor (PRM) operations, where controllers must detect and respond to deviations between aircraft on closely spaced parallel approaches in time to issue breakout instructions safely.
Plain English
A radar that shows where aircraft are with very fast, frequent updates -- so controllers see movement almost in real time instead of waiting several seconds between sweeps.
Context Anchor
Seen in Precision Runway Monitor approach procedures, especially when aircraft are flying approaches to closely spaced parallel runways.
Derivation
"Update" here refers to how often the radar refreshes the displayed position of an aircraft. "High-update" simply means the refresh happens more often than on conventional radar. Standard ATC radar updates every 4.8 seconds or so as the antenna rotates; high-update radar refreshes once per second or faster, giving controllers a much more current picture.
Why Pilots Care
It makes safe simultaneous landings possible on parallel runways spaced as close as 3,400 feet by giving controllers immediate position data to detect and resolve conflicts quickly.
Analogy
It is like the difference between a map that updates your car’s location every second and one that updates only every few seconds. The more frequent update makes small changes easier to see sooner.
Intuition Check
High-update does not mean the radar beam is stronger or that the pilot sees a better display. Here it means the controller’s radar display is refreshed more often.
Example Sentence 1
PRM approaches require high-update radar so controllers can react quickly if an aircraft drifts toward the adjacent final approach course.
Example Sentence 2
High-update radar allowed the monitor controller to issue a breakout instruction within seconds when one aircraft began to drift toward the other.