When should systems experts be consulted?

• A. It is never needed.
• B. It depends on the color of the aircraft.
• C. It is only for engine malfunctions.
• D. The role of systems experts arises when evidence indicates potential system-level failures or knowledge gaps.

Answer: (D)

Consult systems experts when the evidence points to issues that involve how multiple parts of the aircraft interact, not just a single component in isolation. In a mishap investigation, complex system behavior, such as interdependencies between avionics, electrical power, hydraulics, or software logic, requires specialized knowledge to interpret how failures propagate and what the true root cause might be. Systems experts bring deep understanding of system architecture, interfaces, and failure modes, helping to analyze data, reconstruct sequences of events, and form a defensible conclusion. They’re not needed for every issue, and the color of the aircraft is irrelevant; they’re specifically called in when evidence suggests a system-level failure or when there are knowledge gaps that require expert interpretation.