Sharkskin Coating Reduces Airliner Fuel Use, Emissions

The aviation industry is always seeking advancements to improve efficiency and reduce carbon emissions. The former is due to the never-ending quest for profit, while the latter helps airlines maintain their social license to operate. Less cynically, more efficient technologies are better for the environment, too.

One of the latest innovations in this space is a new sharkskin-like film applied to airliners to help cut drag. Inspired by nature itself, it’s a surface treatment technology that mimics the unique characteristics of sharkskin to enhance aircraft efficiency. Even better, it’s already in commercial service!

From The Ocean To The Sky

The riblets, as seen on the scales, or “denticles,” of a shark’s skin. The riblets are the ridges seen here, aligned left-to-right. Credit: Pascal Deynat/Odontobase, CC BY-SA 3.0

Nature often holds the keys to groundbreaking technological advancements. What it has figured out over millions of years can teach us a lot today. In this regard, the shark has skin unlike any other marine creature. Evolution has bestowed upon it a somewhat rough and ribbed skin. This complex natural structure is credited with reducing drag as the shark navigates through water.

Two major components of sharkskin play into this role. The first is a complex interaction with the passive way the shark’s scales respond to water flows.  The second is the “riblet” features on the scales of the shark’s skin. This feature has been explored as a potential drag-saving tool for everything from swimsuits to cars. Riblets are essentially like small keels on the skin, which are aligned with the flow direction of the water flowing over the shark’s body.

Typically, you’d expect the extra wetted surface area created by the riblets to increase drag, but they do quite the opposite. The mechanisms are still not fully understood, but research has revealed some of the secrets involved. Under typical turbulent flow during swimming, vortices form above the riblet surface, only interacting with the tips of them. This leaves a lower-velocity channel in the valleys between the riblets, reducing sheer stresses in the fluid in this area over the majority of the riblet surface. As a whole, vortex translation across the skin surface is also reduced by the riblet structures.  This reduces turbulence overall by virtue of reducing vortexes bursting, tangling, and otherwise negatively interacting with each other.


Lufthansa expects to make major savings by using the AeroSHARK film. Credit: Lufthansa Cleantech Hub

Engineers at Lufthansa Technik and BASF saw an opportunity to translate the hydrodynamic marvel of riblets into the aerospace realm. The result of that work is AeroSHARK, an adhesive riblet film designed to reduce fuel consumption, and in turn, emissions from aircraft.

This innovative film, though subtle in appearance, is poised to make a significant difference in the aviation world. The surface of AeroSHARK boasts millions of prism-shaped “riblets”, each no more than 50 micrometers high, or approximately 2/1000ths of an inch. When applied to an aircraft, this film emulates the drag-reducing properties of sharkskin.

Its potential benefits are substantial. Swiss International Air Lines (SWISS), having recognized the promising nature of this technology, calculated that by applying 950 square meters of this film to a Boeing 777-300ER in specific patterns aligned with the airflow, fuel consumption could be reduced by 1.1 percent. SWISS will apply the film to its full fleet of twelve Boeing 777-300ERs, and expects a total annual reduction of 4,800 tons of jet fuel and a corresponding decrease of approximately 15,200 tons of carbon dioxide emissions.

Workers applying the film to a Lufthansa aircraft. Credit: Lufthansa Cleantech Hub

Similarly, Lufthansa has announced its plans to integrate AeroSHARK into its entire cargo freight fleet, including ten Boeing 777s. This move is estimated to save 3,700 tons of jet fuel and prevent 11,700 tons of CO2 emissions annually. It’s believed the film could be slightly more effective on cargo aircraft, which don’t have rows of passenger windows to work around.

Obviously, to go into commercial service, the AeroSHARK film has to be able to withstand the rigors of the flight environment. The film is reportedly resilient against weather extremes, UV radiation, and the considerable temperature and pressure fluctuations encountered during long-haul flights. Moreover, when applied to wing surfaces, the flow modification can even aid in generating extra lift, further increasing an aircraft’s performance.

Future work to refine the technology is ongoing, particularly with regards to expanding its application to other aircraft types. Initial calculations suggest that with further development, AeroSHARK could cut CO2 emissions by up to three percent.

The key will be whether or not the material will hold up over time and maintain its performance in real world use, where grit and grime could threaten its performance potential.  If the material does work in practice, and doesn’t create undue maintenance hassles, expect it to quickly become popular with airlines across the globe. The idea of a 1 percent saving in fuel costs for the upfront price of some sticky film is one that no airline could ignore.

67 thoughts on “Sharkskin Coating Reduces Airliner Fuel Use, Emissions

  1. Great article, very interesting! Just a heads up though, I think there’s a mistake in sentence two. Unless I’m completely missing the joke, the former “latter” should be the “former”.

      1. also shear not sheer, but good writeup.

        One of the issues with this is as noted accumulation of debris. People knew for a long time how geckos manage to stick to walls so effectively, but it took quite a bit longer to figure out how they managed to *not* stick to dust and grime that would get all over their foot pads and prevent them sticking to walls. Figuring out how to build high surface area, microcontoured surfaces that also stay clean is a much bigger challenge.

        This is also interesting because on some sections of the aircraft body this is pretty easy to apply, but anywhere that there’s anything interesting going on, like the wing root, the flow lines aren’t parallel to each other and it’s much trickier to align the riblets with the flowlines.

        1. I used to race sailplanes, the first attempt at commercializing sharkskin-like coatings was an expensive film for application to sailplane wings. Testing did show a noticeable increase in performance, but only for a few flights. It was pretty much impossible to clean off accumulated remnants of smashed bugs without damaging the film.

  2. “The latter is due to the never-ending quest for profit, while the latter[…]”
    The latter “latter” seems appropriate, but should the former “latter” be “former” rather than “latter”?

  3. Planes and Olympic Swimmsuit using Sharkskin since a decade. Its expensive. Here in Europe Plane fuel is tax free, so flying is cheaper than using train (especially in Germany). I think some kind of tax is comming, so they use the expensive sharkskin foil again to reduce fuel or emission to nature.

    1. Americans need to stop confusing “Europe” with “Germany” lol. I read that so often, it’s quite frightening… It’s like saying “some US State” is “the USA” lol

    1. Riblets stick up. You would have to mill away all the metal from between the v shaped ribs. Their shape is like the figure above that looks like an odd letter M. That metal is needed for strength, and the milling operation might introduce cracks. Better to stick with the film. But I do wonder if it comes colored, so it can replace the paint.

  4. The America’s Cup teams found something similar with fish scale patterns on boats back in the late 80’s early 90’s. To my knowledge most of the worlds cargo fleet had incorporated by the end of he 90’s and had seen great savings. However the maintenance required removed most of the savings.

    1. At least it’s a start. I don’t think we’ll ever get a big win that will solve pollution. If we ever beat it then it will be small percentage changes like these that get us the change we need.

  5. Yes, and another technical solution for a nontechnical problem! Let’s put a bunch of plastic stuff (made out of crude oil) on all our planes to save 1% of jetfuel (made out of crude oil), what can possibly go wrong?
    Is this stuff even theoretically able to save more fuel than it wastes during production?
    The real problem is that airline travel is much too cheap and subsidized way too much. Do our lives really suck so hard that we need to travel at least once a year and take it for granted to fly that much?

    1. >Is this stuff even theoretically able to save more fuel than it wastes during production?

      They stated a savings of 300 Tons of fuel per year. The film surely weights much less than 300T, so, the process would have to be grossly inefficient to use up 300T worth of petroleum products to make.

      What would possibly/probably cause the waste would be cleaning and maintenance, using labor and chemicals and lots of water to clean off dead bugs and such.

      1. Yes TFA says that.

        It does not however say anything about the functional life of the film.
        Rather it raises the question.

        Glue that holds up to airliner speeds isn’t just going to peel off. The costs of using his film is much more than the cost of the film. Parking airplanes is expensive.

        1. Airlines already use stickers and decals for their aircraft liveries so this isn’t so new, and they already are able to take those off. I’m pretty sure you’re complaining about a solved problem.

          1. Most liveries are painted.

            Normal stickers aren’t replaced every 3 flights. Repainting an airplane is very expensive. It’s only a ‘solved problem’ when done on multiyear cycles.

          2. Why would you assert with such confidence that this would have to be replaced every 3 flights. I’d bet that a pressure washer would remove any smooshed bugs and get it back to its efficiency aims. Let’s not forget that smooshed bugs are a problem regardless of whether you have this film.

          3. Because this has been tried before, as have related technologies like vacuuming the boundary layer into the wing. See the first post…

            They ALL don’t work, they get clogged with bugs. Bugs are abrasive, as is water. You blast the bugs off, you also blast off most of the film.

            It’s been _decades_ of effort and no systems are deployed. Not even on racing planes, where they could get replaced regularly.

    2. Considering the amounts of pollution generated by american car users combined with industry, airplanes dont pollute that much. If you want to bite at mass transport systems that pollute, then go for shipping, those boats burn what is basically heated tar. Plenty of pollution there for everyone, in gas and particulate forms. Add the practice of emptying the crap tanks straight into the international waters and the venerable airplane becomes a minor polluter.

  6. If there were such a thing as a “social license to operate” the first removal would be your champions on private aircraft, so this statement was nonsensical and useless, and really undercuts reporting on cool technology. I almost always ask people if they read HaD to see if they will be familiar with a story I read on here, and more and more I’m getting the response of “HaD is just unreadable these days”, or “HaD makes me want to gouge my eyes out recently”. I don’t have insight into your traffic, but I can say my peer group (engineers) has been leaving more and more, and statements like the cited one aren’t helping. I usually just refuse to click and go find better reporting on the mentioned article, but since it was just last night I had yet another friend tell me they stopped reading HaD, it was fresh in my mind….

    1. Politicians will never stop flying private. Other peoples money sure spends sweet. Not my ‘champions’ at all, but you do you.

      They all love the Toilet Security Agency, more overpaid patronage jobs to give out. They don’t get prostate exams at security, like the plebes.

    2. The articles are increasingly just parroting research press releases (“Someday, we’ll be able to psychoacoustically levitate in our private frammus using this unverified marginal effect discovered by people who can’t implement it.”). When we start getting to the worst of the worst – nutrition articles – that’ll be the end.

      1. Arts and crafts ‘hacks’…Already circling the drain.
        Remember the twine wrapped old tire table? That was particularly stupid.
        All the idiotic youtube clickbait ‘hacks’?

  7. No doubt a similar effect to that of the dimples on a golf ball, adding a lubricating boundary layer, allowing for a more laminar flow with only air itself for friction, by increasing the rate it can drag on itself and thus decreasing the effective surface area presented to the oncoming air. Although my guess would be a shark skin coating would only prove more efficient if the object was moving in a linear fashion and not rotating.

  8. Sharkskin airplane coatings – just in time to fix ongoing issues with both Airbus and Boeing:

    1. Paint issues on Qatar’s A350 jets have put the carrier in a bitter legal dispute with Airbus. Take a look at 2 of the grounded planes.

    2. Airlines around the world have raised concerns about Airbus’ A350 paint issues, and now Qatar is seeking over $600 million in damages from the planemaker

    3. Boeing applies for FAA certification to fix 787 paint peeling issues

    1. Airplane paint is complicated and expensive. Duh.
      Modern eco-friendly paint sucks balls. Duh.

      But not so complicated that they’ll start wrapping airplanes in bug collector film. This isn’t ready for prime time.

  9. The sticker adds five horsepower!

    Well, the automotive meme might have a semblance of truth to it if the sticker saves 3 horsepower to maintain highway speed.

    I’d wrap my car for this!

      1. There is actually a better solution for the lower speed of cars. The Mercedes-Benz Bionic is actually copying the aerodynamic shape of the Boxfish. Theres is allways the right solution for your problem. You dont need an Jet Engine for a Lawn Mower or TNT for tendering a Steak.

  10. There is another ‘shark skin’ technology that is an aerospace spec paint.
    Since this technology is a paint and not a plastic film it would eliminate the extra weight issue.
    In addition this technology has a US 11,441,048 patent that touts keeping the ‘riblets’ clean (shark skin ) by use of a chemically tied molecule that lowers the surface energy of the coating keeping dirt and derbies from fouling the riblets.
    Follow the below link for this patent;

  11. To the Author, Thank you good article.
    Like you wrote to ‘mimic’ the shark Skin, everything that is technically reproduced from the nature belongs to Bionics. Can you please add the Tag Bionics to this article? And im not complette sure but i think mimic is more used in chemical reations that are copied from nature than technical uses.

    These is only copying the nature but i wonder what solutions A.I. will bring us. Like confucios once said the most honourable way to do something is to think or in this way: Naaa…. let the A.I. do it for you :-D

  12. How much does this stuff weigh? Airlines STOPPED painting airc aft so they could save weight because weight equals fuel. Technically the paint would have been a smoother and more aerodynamic surface for the airplane, but – aerodynamic effectiveness didn’t account for the weight of all the paint so the just left it off. Does the aerodynamic effectiveness of sharkskin outweigh its weight penalty???

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