 Koenig-Warthausen was determined to win the prize and persuaded his parents to buy him a Klemm Daimler L.20B.This aircraft, registration number D-1433, which he named "Kamerad", was a two-seater low-wing monoplane with an empty weight of only , a top speed of and landing speed of just , and powered by an air-cooled, two-cylinder Daimler-Benz F-7502 boxer engine delivering only This aircraft, with its high aspect ratio and very low wing loading, would today be classified as an ultralight.Koenig-Warthausen took off from Berlin Tempelhof Airport at midnight on 9 August 1928, having less than 20 hours solo flying experience, only five of those in the Klemm.