Central Modals in an Aviation Corpus: Frequency and Distribution

Modality in English is discussed, & a group of nine modal auxiliaries is delimited as "central modals." The development of terminology as a field of scientific inquiry, Eugene Wuster's (1998) general theory of terminology, & Simplified English as the specialized language of aviation technical manuals are mentioned before a quantitative study in corpus linguistics is reported. The occurrence frequency of English central modals in three Boeing 737 manuals is investigated, & comparisons are made between individual manuals & between the aviation corpus, as represented by these three manuals, & between the aviation corpus & the Freiburg-Brown Corpus of American English (FROWN). A significant degree of context-dependent variation in the use of modal verbs & the structure type they occur is found in the aviation corpus. Substantial differences were also attested between manuals addressed to pilots vs mechanics, each demonstrating distinct preferences for individual verbs. As a group, central modals are used 50% less frequently in the aviation corpus than FROWN. Individual verbs, however, differ in frequency variation & occurrence disparity, which is explained by the relative little use of epistemic modality in the manuals. It is concluded that this quantitative study of central modals in different corpora provides evidence that the specialized English of aviation is a simplified language. Tables, Appendixes, References. Z. Dubiel