Languages are like living creatures. Each language has its own biological specifications that distinguish it from other languages; and aviation English is no exception. As special language which is used by specific persons at specific situation, aviation English is deviated syntactically from normal English. The ultimate purpose of this book is to provide an accurate and reliable description of how aviation English, in general, and radiotelephony English, in particular, are structured and used. It presents detailed quantitative and qualitative information of the distribution of syntactic features in aviation English. These syntactic features of are analyzed according to two levels: word level and sentence level.