Prince Henry of Prussia (1862–1929) became the club's patron. Henry was interested in motor cars as well and supposedly invented a windshield wiper and, according to other sources, the car horn. In his honor, the "Prinz-Heinrich-Fahrt" (Prince Heinrich Tour) was established in 1908, like the earlier Kaiserpreis a precursor to the German Grand Prix. Henry and his brother William gave patronage to the Kaiserlicher Automobilclub (Imperial Automobile Club). Henry also was an early proponent of introducing submarines and airplanes. He had merchant ships converted into seaplane tenders for operations in the Baltic Sea. Henry respected his brother, but this attitude was not returned in the
Prince Friedrich Sigismund of Prussia (1891–1927) Prince Friedrich Sigismund of Prussia (1891–1927) Prince Joachim Viktor Wilhelm Leopold Friedrich Sigismund of Prussia (17 December 1891 – 6 July 1927) was a German World War I fighter pilot and member of the House of Hohenzollern. He was the son of Prince Friedrich Leopold of Prussia and Princess Louise Sophie of Schleswig-Holstein-Sonderburg-Augustenburg, married in 1916. At Glienicke Castle, Prince Joachim Viktor Wilhelm Leopold Friedrich Sigismund was born to Prince Friedrich Leopold of Prussia and his wife Princess Louise Sophie of Schleswig-Holstein-Sonderburg-Augustenburg on 17 December 1891. He was their second child and eldest son; his siblings would come to include