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Thermoplan

The Thermoplan is a Russian lenticular-shaped hybrid airship. The key feature of Thermoplan is its two section structure. The main section of the airship is filled with helium, while the other section is filled with air that can be heated or cooled by the engines. This unusual design, historically known as a "rozière", greatly improves the manoeuvrability compared to an all-helium type. The disc shape is also intended to improve manoeuvrability and to help resist winds up to .

The project was started in the late 1980s, with the first working prototype tested in 1991. That was a rather small airship, and a full-scale model was not built at that time due to problems caused by the economic crisis of the 1990s. In the late 2000s, the project was revived under the name Locomoskyner ( Локомоскайнер) by the Russian company Lokomosky in Ulyanovsk.