This Aerospace Recommended Practice will identify the problem with latency in the pilot's instrument control of an aircraft. Recommended evaluation techniques to characterize control problems will be documented.
Display latency is caused by excessive time delays in modern digital flight displays, particularly with imaging displays. The result of these delays is addition of phase delays in the control loop when the pilot closes the loop while flying by reference to the aircraft instruments. Control difficulties often appear when the pilot tries to perform precise high gain tracking tasks. The problem is similar to excessive latency in the flight controls. Because pilots learn to reduce their gains when confronted with latency problems, particular evaluation tasks are necessary to finds these problems. This ARP will describe display latency evaluation techniques.