German engineer and inventor of the Wankel rotary engine. The Wankel engine is distinguished by the presence of an orbiting rotor in the shape of a curved equilateral triangle that does the work done by the moving pistons in other internal-combustion engines. Advantages of the Wankel engine include light weight, few moving parts, compactness, low initial cost, fewer repairs, and relatively smooth performance.

Wankel, originally a sealing specialist, carried out development work on rotary valves between 1936 and 1945 with the German Aeronautical Research Establishment DVL. In 1951 he began working in Lindau with the research department of the NSU Motorenwerk AG, based at Neckarsulm. He completed his first design of a rotary-piston engine in 1954, and the first unit was tested in 1957. Mazda (Mazda Motor Corporation), a Japanese automobile company, produced and developed the Wankel engine, introducing it to the American market in 1971. During the next few years, poor fuel economy and a world oil crisis discouraged buyers, but the engine was constantly improved, and by the end of the decade the company's sports cars were being enthusiastically received in Europe and the United States. Wankel became director of his own research establishment at Lindau, where he continued to investigate the fundamental problems and future applications of the rotary-piston engine.