Sharks inspire eco innovation with riblet technology

The technology, which is inspired by the streamlined surfaces of shark skin, was first adopted by some airlines in 2022, and is now being rolled out across the industry, promising more efficient air travel.

What is riblet technology?

Riblet technology is based on mimicking the skin of sharks, which are covered with tiny, tooth-like structures known as dermal denticles. These create a ribbed surface that reduces drag as sharks move through water, allowing them to swim faster with less energy.

The development of riblet technology began decades ago when researchers recognised the drag-reducing properties of shark skin. Over time, this has led to the creation of functional films that can be applied to aircraft surfaces, reducing air resistance in a similar way.

Recognising this, researchers began developing riblet technology over the years, which eventually led to the creation of functional films that can be applied to aircraft surfaces to reduce air resistance in a similar way.

Riblet technology and aviation

Riblet films, such as AeroShark, replicate the microstructure of shark skin by using millions of tiny, prism-shaped riblets. These structures are designed to align with airflow over the aircraft's surface, reducing drag and improving aerodynamic performance. The films can be applied to large areas of the fuselage, with some installations covering hundreds of square metres.

By reducing drag, riblet technology lowers the amount of fuel needed to keep the aircraft flying. Lufthansa Cargo, for instance, reported that the AeroShark film, which it began applying to its Boeing 777 fleet in early 2023, has resulted in over 1% fuel savings. One per cent may not sound like a lot, but the cumulative impact is considerable, particularly for large fleets operating across global routes. In the case of Lufthansa’s savings, this translates into significant environmental benefits: for every 10 aircraft, the savings amount to approximately 4,000 tonnes of kerosene and 12,000 tonnes of CO2 emissions per year.

The technology is also easy to implement and can be adapted for other vehicles, such as trains and cars, where drag is also a concern.

Challenges and potential

Despite its potential, riblet technology does face challenges. One of the main concerns is contamination: dust and debris can build up on the delicate riblet structures, reducing their effectiveness. Keeping the riblets clean can be costly, which has limited the widespread adoption of the technology in the past. However, new developments, such as laser structure coatings, may provide ways to apply the technology more efficiently without adding extra weight to the aircraft.

Research into riblet technology continues to evolve, and scientists are exploring additional benefits beyond drag reduction. For instance, there is growing evidence that riblet-covered surfaces may have de-icing properties, helping to prevent ice build-up on aircraft during cold weather conditions. This could reduce the amount of energy and chemicals needed for de-icing, further improving environmental performance.

Another potential application of riblet surfaces is noise reduction. By altering the way airflow interacts with turbine blades, riblets could help lower noise levels, creating a quieter and more pleasant experience for passengers and those living near airports.