SAE ARP 450D:1980-12-01

This ARP sets forth design and operational recommendations relative to the integrated alerting system to be implemented on the flight deck. It is intended that through the adoption of the design objectives and recommendations incorporated herein, a consistent and effective industry standard will result. Safety of flight is greatly enhanced by an alerting system designed to provide early crew recognition of flight crew operational error as well as aircraft system or component status or malfunction. The alerting system therefore relates to aircraft configuration and flight regime as well as the aircraft systems. To fulfill this objective, the flight deck alerting system must attract the attention of the crew, must state with clarity the nature and location of the problem, must be highly reliable and thoroughly responsive to the operational requirements and environment. The system should incorporate careful design logic to assure that warning or caution signals never occur when operations are normal and always occur when required.