14 CFR § 25.1302

Flight deck controls must be installed to allow accomplishment of all the tasks required to safely perform the equipment's intended function, and information must be provided to the flightcrew that is necessary to accomplish the defined tasks.

Flight deck controls and information intended for the flightcrew's use must:

Be provided in a clear and unambiguous manner at a resolution and precision appropriate to the task;

Be accessible and usable by the flightcrew in a manner consistent with the urgency, frequency, and duration of their tasks; and

Enable flightcrew awareness, if awareness is required for safe operation, of the effects on the airplane or systems resulting from flightcrew actions.

Operationally-relevant behavior of the installed equipment must be:

Predictable and unambiguous; and

Designed to enable the flightcrew to intervene in a manner appropriate to the task.

To the extent practicable, installed equipment must incorporate means to enable the flightcrew to manage errors resulting from the kinds of flightcrew interactions with the equipment that can be reasonably expected in service. This paragraph does not apply to any of the following:

Skill-related errors associated with manual control of the airplane;

Errors that result from decisions, actions, or omissions committed with malicious intent;

Errors arising from a crewmember's reckless decisions, actions, or omissions reflecting a substantial disregard for safety; and

Errors resulting from acts or threats of violence, including actions taken under duress.