A methodology for improving mode awareness in flight guidance design

Describes the application of an informal approach to identify and reduce potential sources of mode confusion early in the development cycle when changes can be made at reasonable cost. A checklist of potential sources of mode confusion was developed through a literature review, then applied to a representative specification of a flight guidance system documented in the RSML^-e notation. The potential sources of mode confusion identified through use of the checklist were then reviewed with pilots, engineers, and other domain experts. While most of the issues identified were determined to be benign, or even natural consequences of conforming to existing aviation conventions, several concrete recommendations were made to improve mode awareness.