Abstract: A turbofan engine augmenter includes an exhaust casing and a combustion liner therein which define therebetween a cooling duct for receiving bypass air. A diffusion liner adjoins the combustion liner and defines with the casing an outer inlet for receiving the bypass air, and a radially inner inlet for receiving core gases. A ring flameholder includes an aft facing radial wall adjoining the diffusion liner, and an integral axial wall adjoining the combustion liner. A plurality of circumferentially spaced apart radial flameholders extend inwardly from the casing and through the diffusion liner forward of the ring flameholder, and each includes a first fuel spraybar for injecting fuel into the core gases. A mixer defined by a plurality of injector chutes extends radially inwardly through the diffusion liner, with the chutes being spaced between respective pairs of the radial flameholders.