Who first identified the basic form and elements of a modern airplane?

Sir George Cayley is credited with laying the foundational principles of modern aviation. In the early 19th century, he was the first to recognize and articulate the essential aerodynamic elements that must be present in a heavier-than-air flying machine. Cayley identified the importance of lift, drag, thrust, and weight, which are the four forces acting on an aircraft in flight.

His design concepts included a fixed-wing configuration with separate mechanisms for lift and propulsion, which are integral to contemporary airplane designs. He built and launched successful gliders and conceptualized what would become the modern airplane's structure. This pioneering work set the stage for future advancements in aviation and influenced later figures such as the Wright brothers, who built upon Cayley's principles to achieve powered flight.