History, a projection of the future: A rotary wing perspective

The success and failure of past vehicle concepts is reviewed in an attempt to highlight some of the advanced vehicle concepts attempted in the past failed because of a lack of appreciation, by both the sponsors and the developer, for the technical and societal requirements critical to their success. This paper will review the history of some attempts to provide both good hover and forward flight efficiency and will point out some of the technical and societal obstacles encountered. Two examples, that of the tiltrotor and tiltwing vehicles. will be highlighted show the different paths followed by a successful and an unsuccessful concept. The outlook for future VTOL/rotary wing concepts will be evaluated.