The laboratory measurements in February 2022 marked the official start of the UAII2022 campaign, which is composed of laboratory tests of the participating radiosondes that take place before and after the main sounding phase scheduled for August/September. Against the background of the ever-present Covid-19 situation, which lead to several postponements in the past, the campaign commenced successfully, and the first four laboratory slots were executed smoothly and according to plan. The laboratory tests yielded useful information and ...