Wilhelm Düerkop (born 30 June 1928 in Halberstadt) is a German glider and motor glider aerobatic pilot and promoter of glider aerobatics in Germany for many years. He is known by the nickname Salzmann (meaning "salt man" in German). This is because he was a pit foreman in a salt mine.
Together with his colleague Hannes Mattes, he performed synchronised motor glider acrobatics using a Fournier RF-4 and an RF-5 at many air shows, until Hannes Mattes died in 2004. Later, Wilhelm Düerkop joined the Skydance-Acro-Team and still performs motor glider aerobatics with an RF-4.
He owned two Lo 100 gliders a yellow one (christened "Gilb") and a white one, but he now has a modified Schempp-Hirth Cirrus, known as a Cirrus K ("Langohr Eater"). To help promote glider aerobatics, Düerkop lends his gliders to both learners and competition pilots. He sometimes trains advanced learners on aerobatics courses but he especially helps as the tow pilot using his Piper PA-18 "D-ELUF". He has also volunteered at many glider aerobatics events.
The modification of a Standard Cirrus into a Cirrus K was initiated by Wilhelm Düerkop in the late 1980s. He still owns the prototype, while the second one is owned by his nephew Wolfgang Seitz.
The Lo100 "Gilb" is now owned by the Förderverein Segelkunstflug im BWLV. It is regularly lent for use on aerobatic courses in Germany.
An ASK 21 that is owned by the glider aerobatics club Fördervereins für Segelkunstflug im BWLV e.V. has been christened "Salzlore", which means "salt lorry" in German, after Wilhelm "Salzmann" Düerkop and the president of the aeroclub of Baden-Württemberg Lore Sturm. This club was founded in 1985 and has about 1250 members.
The German club championships in glider aerobatics are named Salzmann-Cup after Wilhelm "Salzmann" Düerkop. There are three classes in each competition: the sportsman class, the advanced class and the unlimited class. The Salzmann-Cup plays a similar role as state championships in Germany. In the unlimited category, it is a qualification contest for joining the national team. A team prize is also presented based on the combined results in all the classes for the pilots of each club. Additionally, the title "Salzmann des Jahres" (Salt Man of the Year) is awarded for unselfish conduct and sportsmanship.