On a simplified method to produce hydrophobic coatings for aeronautical applications

The deposition of ice on wings and tails surfaces of aircrafts often alters the airflow reducing the lift force and causing aerodynamic stall. In order to prevent these kind of serious problems, de-icing and anti-icing systems, which act by removing the ice once it has formed, and by preventing its formation, respectively, are usually employed. In particular, the anti-icing superhydrophobic and icephobic coatings can be achieved by designing and realizing nanostructured surfaces by taking inspiration from effective surface present in nature, e.g., the lotus leaf. However, this process is often expensive and requires specialized equipment. The effort of the present work is to find out a simplified and not-expensive method to prepare superhydrophobic coatings to be applied on large aircraft surfaces. Among the investigated methods, the deposition of several layers of a homogeneous hydrophobic silica nanoparticles by using a simple aerograph allowed to build-up a coating which exhibits a contact angle of 154°. The coating withstands to aging tests simulating flight conditions. Also during typical flight conditions, i.e., -12 °C and 0.5 bar, it retains its hierarchical superficial morphology with roughness features from nano- to micro-scale and shows contact angle higher than the commercial reference.