Later a series of disclosures by the press, several hearings and an investigation evolved around the acquisition of the HS.30. Witnesses, like the former ambassador of Germany in Switzerland Friedrich Holzapfel, were heard and a story about potential payments made to individuals and political parties was spread, based on claims made by the then lobbyist and 1930s Weimar Republic secretary Gottfried Treviranus and businessman Werner Plappert. According to Dieter H. Kollmar, the progress of the official investigation was hampered by witnesses just craving for recognition and charlatans. Accusations, made in that context against Franz Josef Strauss, later proved to be false. Kollmar saw the problems with the HS.30 in the fraudulent practises of Hispano-Suiza and insufficient controlling processes in the Federal Ministry of Defences procurement plans.