Tsiolkovsky studied the mechanics of lighter-than-air powered flying machines. He first proposed the idea of an all-metal dirigible and built a model of it. The first printed work on the airship was "A Controllable Metallic Balloon" (1892), in which he gave the scientific and technical rationale for the design of an airship with a metal sheath. Tsiolkovsky was not supported on the airship project, and the author was refused a grant to build the model. An appeal to the General Aviation Staff of the Russian army also had no success. In 1892, he turned to the new and unexplored field of heavier-than-air aircraft. Tsiolkovsky's idea was to build an airplane with a metal frame. In the article "An Airplane or a Birdlike (Aircraft) Flying Machine" (1894) are descriptions and drawings of a monoplane, which in its appearance and aerodynamics anticipated the design of aircraft that would be constructed 15 to 18 years later. In an Aviation Airplane, the wings have a thick profile with a rounded front edge and the fuselage is faired. But work on the airplane, as well as on the airship, did not receive recognition from the official representatives of Russian science, and Tsiolkovsky's further research had neither monetary nor moral support. In 1914, he displayed his models of all-metal dirigibles at the Aeronautics Congress in St. Petersburg but met with a lukewarm response.