An end to unreadable maintenance manuals and incomprehensible translations is in the air. Boeing Co. is offering to Lernout & Hauspie Speech Products NV (L&H), a Belgian world leader in language and translation, its Simplified English Checker, a software package that helps authors of plane maintenance manuals to express themselves clearly and simply. The software ensures that authors use a limited vocabulary and standard terms when describing each operation. Although Boeing designed its Checker for the aerospace industry, L&H Senior Director Geert Adraens says the program already is garnering interest in the automotive world. Boeing says its Checker has reduced the risk of misunderstandings -- many of which can be fatal -- and the amount of time planes spend being maintained.