The primary innovative approach and the major aim of the investigations being covered here is in the first instance to perform reliable and high quality procedures for laminar wing testing under and near flight conditions at high Reynolds numbers in ETW. Beside confirming a number of already mature and successfully applied measuring techniques, these investigations will allow to validate a new evaluation process by quantitatively determining areas of turbulent flow on the wing, e.g. generated by turbulent wedges inside the laminar flow region.. Calculating the difference in drag due to laminar and turbulent flow by post-processing forms a tool for correcting the overall drag as measured by the balance.A second subject of interest is the surface quality of the model to be tested. Special attention will be given to the cleanliness of the model on preparation and the eventual contamination while testing.The experiments will improve the understanding of the flow and the performance of airplanes and are an indispensable tool for airframe manufacturers. At the end the project will help to safe resources like fuel, to reduce the pollution of environment by exhaust gases and noise and finally to increase the safety of flights.