Wankel Diesel engine describes the idea of using the Diesel principle in a Wankel rotary engine. Several attempts to build such an engine have been made by different engineers and manufacturers in the 1960s and 1970s. Due to technical problems and the general disadvantages of the Wankel design, the Wankel Diesel engine never left the prototype stage, and designing a Wankel Diesel engine capable of running under its own power is thus considered unfeasible.