AeroSHARK: gliding through the clouds

Much effort has lately gone into making air travel more efficient and environmentally friendly. In addition to the problem of extremely high fuel costs, the entire aviation sector is under increasing pressure from policymakers and the public to drastically reduce its environmental footprint. This is evidenced by the lively discussion surrounding aircraft fuels produced from biogenic waste (SAF), concepts for hydrogen-powered airplanes and aerodynamically designed aircraft concepts.
AeroSHARK now offers another way to reduce harmful emissions. The underlying concept is as unorthodox as it is impressive.

Nature is the best example

In many areas, nature offers us ideal solutions and designs that we are only too happy to copy. This is true of everything from honeycombs to the spiral shapes of climbing plants and the glide principle of wings. We humans take many of these principles over, and now we have added sharkskin to our list by copying from the fish who have ruled the oceans for millions of years. They glide effortlessly through the water as true masters of minimizing resistance – not only with their body shape but also with their skin. Lufthansa Technik collaborated with the chemicals group BASF to analyze the use of this natural phenomenon and adapt it for use on aircraft to reduce fuel consumption and emissions.

“Panta Rhei – everything flows”

AeroSHARK is a bionic adhesive film modeled after the skin of sharks. The famous efficiency of sharkskin has been utilized to optimize the flow of air around the aircraft, leading to significant fuel savings and emission reductions. The secret lies in the microscopic properties of the film, which features a barely perceptible texture created by small rib-like protrusions, called riblets. The film is divided up to make it easy to apply accurately and consists of millions of the prismatic riblets, each no larger than 50 micrometers (0.05 mm). When applied correctly to the airplane, these tiny miracles boost the efficiency by reducing surface friction and air resistance just like in nature. They also provide additional lift when applied to the wings.

Nothing flimsy about this foil!

The riblet film is easy to apply even on large commercial airliners – it has already been certified for covering up to 500 m² on the lower fuselage and underside of a Boeing 747-400. Clearly, this is not your typical plastic wrap. It is extremely robust and can resist even the large temperature fluctuations and pressure changes encountered in the sky. The ultraviolet radiation at high altitudes was also taken into account in the design.

AeroShark takes off

SWISS got started with the film in October 2022. The innovative technology had already been tested in collaboration with external experts on an initial airplane of type Boeing 777-300ER. The results were impressive, motiving the carrier to upgrade its entire Boeing 777 fleet.

Applying the riblet film over a total of 950 square meters of the fuselage and engine nacelles can yield fuel savings of roughly 1.1 percent. When used on all the airline’s “triple sevens,” this means an annual savings of over 4,800 tons of fuel and up to 15,200 tons of CO₂. According to SWISS, this is the same amount of fuel typically consumed on roughly 87 long haul flights from Zurich to Mumbai. This might not appear so game-changing at first glance, but if gradually rolled out to all suitable aircraft types around the world, the eventual savings would be massive – and all that with the help of just a paper-thin film that can be easily applied during a routine aircraft service check.

In the meantime, a procedure is under development for applying the AeroSHARK modification to the wing surfaces of the Boeing 777 to improve the efficiency still further.

Cargo planes with “skin”

Lufthansa Cargo is also looking to apply roughly 800 m² of AeroSHARK “skin” to its Boeing 777F cargo fleet. Measured over ten aircraft, the expected reductions in air resistance should lead to an annual fuel savings of 3,700 tons and a reduction in CO₂ emissions by 11,700 tons.

The riblet technology can be adapted to all aircraft types with a similar effect, and Lufthansa Technik is already planning to have it certified for additional surfaces and aircraft types in the near future. In times of extremely high fuel costs and a decline in global cargo volume due to inflation, airlines have to find every available opportunity to lower their operating costs. At the global level, this new technology could be a powerful tool for decreasing fuel consumption and the associated costs.

The skies of the world are currently home to roughly 24,000 aircraft – and while it may be a long way off, AeroSHARK has the potential to save roughly two million tons of jet fuel and 6.3 million tons of CO₂ per year.

“Flying Sharks”