Communicating safety: a corpus study of WARNING, CAUTION, and NOTE instructions in aviation maintenance manuals

Abstract Aircraft maintenance personnel worldwide rely on WARNING, CAUTION, and NOTE instructions to prevent injuries, equipment damage, and accidents. However, systematic linguistic analysis of these instruction types has received limited attention in applied linguistics research. Through novel multidimensional analysis of over 70,000 deduplicated safety instructions (1.18 million tokens) from six aircraft families, this study identifies a five-dimensional framework distinguishing instruction types: (i) Action versus Information, (ii) State versus Cause, (iii) Elaboration versus Simplification, (iv) Prevention Focus, and (v) Outcome Focus. Results reveal distinct functional profiles: WARNING uses action-oriented imperatives with explicit causality, CAUTION employs simplified conditionals emphasising prevention, and NOTE uses elaborate constructions for technical state descriptions. These findings inform technical writing assessment, register-specific training design, and controlled language refinement while contributing to understanding how safety-critical registers encode risk through grammatical patterning.