At the moment, the windtunnel model of the Clean-Sky-2 Project GRETEL (GREen Turboprop Experimental Laminar Flow WTT) with nearly five meter wingspan is taking shape at our production. INVENT not only produced the CFRP main structure components, but is also responsible for the assembly process of the whole wing. This is mainly a matter of precision, because with this wing model a modern aerodynamic concept should be validated during the windtunnel testing. By the way, the neon-yellow-dot-pattern will be used to detect the deflection of the wing troughout the tests and was directly integrated during manufacturing to maintain a flush surface.