Human communication, mutual awareness and system dependability. Lessons learnt from air-traffic control field studies

The dependability of many complex and critical systems strongly relies on h uman operators, both through human reliability and human ability to handle adequately the unexpected events. This paper focuses on ergonomics field st udies of air traffic control activities, and more specifically on the analy ses of communication within teams of controllers. We show how operators use spontaneously the natural redundancy and diversity of human communication (multimodality, addressing features,...), so as to successfully maintain mu tual awareness. This is the key for reliable cooperation, for the sake of g lobal system dependability that rests on mechanisms such as error detection , recovery, and prevention (by anticipation and regulation). This study hel ps in providing specifications for the design of systems efficiently suppor ting both human cooperation and human ability to contribute to dependabilit y. (C) 2001 Elsevier Science Ltd. All rights reserved.