Bücker Bü 131 Jungmann Bü 131B Dornier-Werke Altenrhein

Switzerland was the Jungmann's most loyal foreign customer. According to the 1983 Air Britain Digest, the Swiss Air Force evaluated the Bü 131B and decided to adopt it; the production licence went to Dornier-Werke AG of Altenrhein, on the shore of Lake Constance. By the end of 1936 ten aircraft had already flown: seven for the Aero Club of Switzerland and three for the Air Force, all with the 105 hp Hirth. The sources disagree on the total: the English Wikipedia and the manufacturer's article speak of 94 Jungmann operated by the Air Force, 88 of them built by Dornier; the German Wikipedia puts the Swiss aircraft at 84, 81 of them licence-built, and the Air Britain Digest gives 84. The census therefore sets no figure.

The Jungmann was the Swiss Air Force's primary trainer from 1936 to 1971, according to the German Wikipedia, although in the late 1950s and early 1960s the Pilatus P-2 gradually took over instruction. The retired aircraft passed to the Aero Club and to private owners, and with them came a school of modifications that made the Swiss variant famous: in 1962 the FFW workshop fitted HB-UTH with a 170 hp Lycoming with which Albert Ruesch placed second in the Lockheed Trophy, and other examples received 180 hp Lycomings and the strengthened wings designed by Fritz Dubs for advanced aerobatics. Alongside the Bü 133 Jungmeister, of which Dornier also built a batch, the Swiss Jungmann is today one of the classics most sought after by European collectors.