Human-Machine Interface and Alerting
HMISection 11: Aircraft & Avionics Architecture
Definition
The means by which the flight crew interacts with the avionics system, including displays, controls, annunciators, aural alerts, and haptic feedback. The HMI design must enable the crew to effectively monitor system status, receive alerts and warnings, input commands, and maintain situational awareness under normal and abnormal operating conditions.
Where This Shows Up
HMI design in avionics is governed by human factors requirements derived from certification specifications (e.g., CS-25.1322 for flight crew alerting, CS-25.1302 for installed systems and equipment). Alerts are classified by urgency: warnings (immediate action required, typically red), cautions (timely action required, typically amber), and advisories (awareness, typically green or blue). The alerting philosophy must be consistent across the flight deck and must avoid excessive nuisance alerts that can lead to crew desensitization. Crew workload analysis, as required by ARP 4754A, evaluates whether the HMI design allows the crew to perform all required tasks within acceptable workload limits during normal and failure conditions.
Primary Sources
Flightcrew alerting requirements — defines the regulatory framework for warning, caution, and advisory alerts presented to the flight crew.
Installed systems and equipment for use by the flightcrew — addresses human factors requirements for installed equipment design.
Requires crew workload analysis as part of the system-level validation process.
Related Terms
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