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This paper reviews ejector development at DHC over the past 25 years and focuses on the features proposed for the E7 wind tunnel model. The E7 aircraft is a STOVL project study design by General Dynamics, Fort Worth, which utilizes lift ejector technology developed by DHC (Ref. 1). Efforts to maximize thrust augmentation ratio within the packaging constraints of typical STOVL aircraft configurations are described. Experimental results from antecedents of the E7 ejector are presented together with the latest results from full-scale tests at Lewis Research Center, NASA. The major geometrical parameters are described and their influence on thrust augmentation evaluated. Various nozzle types are discussed. Performance is compared with theoretical trends derived from global compressible theory. A brief look at the installation aerodynamics of a pair of chordwise ejectors, in hover, completes the paper.

The development of the de Havilland Aircraft of Canada (DHC) augmentor-wing powered-lift concept is briefly reviewed from the mid-1960's to the present day. A parallel DHC research program over the period from the mid-1970's to the present day has developed a very thick high speed compound or multi-foil wing section for the Augmentor-Wing concept. This program proved more successful than initially anticipated and has led to the development of both blown and unblown wing sections up to 24% thickness-chord with CL (cruise) greater than 0.6 and design cruise Mach numbers around 0.7, two-dimensionally. This research is also reviewed. More recently, design studies have shown that integration of these technologies leads to very efficient transport aircraft which can achieve Ultra-Stol capability with only the thrust installed for cruise.