AHIS equation describes a new model for instructional system design and develops a system based on Merrill's Component Display Theory incorporating appropriate selection of Media, Ergonomics and Navigation Structures to produce learner engaging and effective learning outcome. A significant component of the proposed model is the integration of principles of Ergonomics having Graphic Aesthetic as one of the constituent. Graphic Aesthetic decides Unity, Proportion, Balance, Sequence, and Cohesion for interface design. Next component is selection of suitable Media as per the categorized learning content. Merrill Component Display Theory has been utilized to categorized learning content. Research shows that media effects are significant in teaching learning process. Third significant component of the model is selection of Navigation structures. Navigation structures decide learner concentration level (learner engagement), restrict them from getting disoriented in hyperspace and finally direct them to their learning objectives. Research in the field of Navigation structures reveals that it's potential for accelerating learning, when employed with well designed interfaces. Hence, time demands development of instructional model which identifies categorized learning content(pj), principles of Ergonomics for Interface Design(ej), Media selection criteria (mj) and selection of appropriate Navigation structures(nj) and improved learner engagement by calculating learner's prior knowledge level based on learner known concepts(kcs[subscript known]), familiar concepts (kcs[subscript familiar]) and new concepts(kcs[subscript new).