Commentary: Lilienthal Was Wrong.

The article focuses on the development and testing process of electric vertical takeoff and landing (eVTOL) aircraft, emphasizing the importance of rigorous design, building, and testing phases. It highlights the Vertical Flight Society’s eVTOL Aircraft Directory, which tracks nearly 800 concepts and about 375 companies or designers, illustrating the industry's rapid growth and diversity. Drawing historical parallels with pioneers like Otto Lilienthal and the Wright Brothers, the article underscores that successful aircraft development requires not only technical achievement but also operational, economic, and safety validation. It concludes that the eVTOL industry is moving from proving technical viability toward achieving sustainable commercial success, with safety, affordability, and customer value as critical factors.