Human-powered aircraft are flying machines that rely solely on human strength for propulsion. These aircraft are typically lightweight and designed to be pedaled or powered by the pilot's physical effort. They often feature large wings to maximize lift and minimize energy consumption, making them an interesting challenge for engineers and enthusiasts alike. The development of human-powered aircraft has led to various competitions, such as the Kremer Prize, which rewards innovative designs that can achieve sustained flight. Notable examples include the Gossamer Albatross, which successfully crossed the English Channel in 1979, showcasing the potential of human ingenuity in aviation.