Implied and Expressed Meanings: Engineering Design,Embodiment,and Documentation for the 737 Max

Abstract

Skills, including piloting skills, are based on procedures (specific meanings), and these procedures can be visible in the form of expressed meanings or invisible and experienced as an embodied sense while operating out of the tacit domain as hidden implied meanings. When procedures are changed as a result of changes in airplane technology, such changes, if not made visible, can violate foundational principles of usability and catch pilots by surprise. Pilots then may experience anxiety and, operating primarily out of a low threshold of consciousness from the tacit domain, without much reflection in the form of feedback from the conscious, operate based on erroneous implied meanings rather than correct expressed meanings. Pilots should, therefore, have technical documentation concerning changes to implied meanings—through expressed meanings in the form of updated procedures and warnings—for making visible changes to implied meanings. Not providing such documentation can lead to catastrophic consequences.