The international language of the aerospace industry is English, and English is the language most used for writing technical documentation. However, it is often not the native language of the readers of such documentation. Many readers have a knowledge of English that is limited, and are easily confused by complex sentence structures and by the number of meanings and synonyms which English words can have. In the late 1970s, the Association of European Airlines (AEA) asked the European Association of Aerospace Industries (AECMA) to investigate the readability of maintenance documentation in the civilian aircraft industry. AECMA asked the Aerospace Industries Association (AIA) of America to assist in this project. The resulting project groups from AECMA and AIA researched the procedural texts in maintenance manuals. The product of this effort was the AECMA Simplified English Guide. AECMA Simplified English was developed to help the users of English-language documentation in the aerospace sector understand what they read, particularly in multinational programs.
Since the first publication of the AECMA Simplified English Guide, other non-aerospace industries have adopted the principles of AECMA Simplified English for their own documentation. AECMA Simplified English is now the Specification ASD Simplified Technical English.
It is not only for those who do not have English as their native language, but also for those who do.