Lufthansa Technik AG (Hamburg; www.lufthansa-technik.com) and BASF SE (Ludwigshafen, Germany; www.basf.com) have developed a surface film, tradenamed AeroSHARK, that mimics the fine structure of a shark’s skin for reducing friction. The technology is to be rolled out on Lufthansa Cargo AG’s (Frankfurt am Main, Germany; www.lufthansa-cargo.com) entire freighter fleet from the beginning of 2022, making the aircraft more economical and reducing emissions.
The surface structure, consisting of riblets — tiny (around 50µm) grooves arranged longitudinally along the flow — that imitates the properties of sharkskin and therefore optimizes the aerodynamics on flow-related parts of the aircraft. This means that less fuel is needed overall. For Lufthansa Cargo’s Boeing 777F freighters, Lufthansa Technik estimates a drag reduction of more than 1%. For the entire fleet of ten aircraft, this translates to annual savings of around 3,700 tons of kerosene and just under 11,700 tons of CO2 emissions — the equivalent of 48 individual freight flights from Frankfurt to Shanghai.
The riblet surface is an example of functional films being developed by the Coatings division of BASF (www.basf-coatings.com) in its Beyond Paint Solutions unit. A solution was implemented together with Lufthansa Technik that fulfills the strict requirements of the aviation industry. Exterior surfaces used in aviation are exposed to factors, such as strong ultraviolet (UV) radiation, as well as temperature and pressure fluctuations at high altitudes, among others. BASF has therefore focused its development on achieving extreme durability and weather resistance. The key criteria for use in aviation operation include simple application and handling as well as ease-of-repair, for which a custom concept has been developed.
Lufthansa Technik and BASF plan to continue developing the new technology consistently to include additional aircraft types and even larger surfaces so that they can support airlines around the globe even more comprehensively in the future in reaching their sustainability goals. Initial model calculations show that use of sharkskin technology at its highest expansion level could reduce CO2 emissions by as much as 3%.