Shell unveils lead-free avgas

Shell revealed today that it has developed a lead-free replacement for 100LL. The lead-free formulation, which comes after 10 years of “exhaustive R&D, as well as successful initial testing” by two OEMs, will now begin a strict regulatory approvals process, according to company officials.

“We are proud of this first for Shell Aviation,” said Xinsheng (Sheng) Zhang, vice president of Shell Aviation. “This advanced product is the latest milestone in our long history of innovation. We believe that with industry support, a stringent approvals process can be completed for this new lead-free product within a short time-frame. We look forward to working alongside our technical partners and authorities to progress the necessary approvals needed to make this product a reality for use in light aircraft engines of all types.”

Avgas currently includes lead in its formulation to meet fuel specifications and boost combustion performance (known as Motor Octane rating). Shell officials say the company has developed an unleaded avgas that meets all key avgas properties and that has a Motor Octane rating of over 100, an industry standard.

“The development of a technically and commercially-viable unleaded avgas that meets these criteria has been seen by the aviation industry as a significant challenge, due to the tight specifications and strict flight safety standards that it has to adhere to,” company officials said in a prepared release.

Shell 3To get to this stage, Shell Aviation scientists carried out an intensive internal laboratory program, including in-house altitude rig and engine testing. Working alliances were then formed with aviation engine manufacturer Lycoming Engines and the Piper Aircraft. As a result, the formulation was successfully evaluated in industry laboratory engine (bench) tests by Lycoming and in a flight test by Piper.

“Lycoming Engines commends Shell on launching its unleaded avgas initiative,” states Michael Kraft, senior vice president and general manager of Lycoming Engines. “They engaged Lycoming to test their fuel on our highest octane demand engine and we can confirm that it’s remarkably close to avgas 100LL from a performance perspective. This initiative is a major step in the right direction for general aviation.”

“Piper Aircraft is pleased to participate with Shell and Lycoming in this feasibility flight test program,” said Piper Vice President of Engineering Jack Mill. “Recently, we successfully flew an experimental non-production Piper Saratoga with Shell’s new formulation for about an hour. We appreciate the opportunity to work with Shell and Lycoming in this preliminary investigation of the technologies, which could in several years lead to flying unleaded fuel in our production airplanes.”

Shell2Shell officials said the company will now work with the aviation industry, regulators and authorities, including the FAA, American Society for Testing and Materials (ASTM) and European Aviation Safety Agency (EASA), to achieve approvals for the unleaded avgas. Shell expects to also work with other OEMs to continue the testing and refinement program as the approvals process progresses.

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  1. Ray says

    It will take another 20 years to see it at the pumps. Not politicaly expedient. Screw the BS and get your glider rating.

  2. walt krupnak says

    I am sure that this unleaded fuel will not solve any problems for GA airplane owners unless the price comes down below the current 100LL prices. Let’s face facts, money is the driving force.

  3. Kent Misegades says

    Mark, this news was not in our blog because it was a general press release. We look for the news behind the news, and will wait a few weeks for the dust on this to settle. One fact appears clear however: this fuel will not solve the number one problem of avgas, its high cost. It appears thus that shells primary concern is to preserve its current high-margin Avgas.

    • Trent says

      Why would they, it is not a growing market and somebody has to pay for that R&D. Prices will only go up, that is the way it works. Invest more, pay more.

      • Mark says


        How did they figure out the affordable IPAD was a multi million unit profit potential back 10 years ago when it was being developed? Because there were multimillion pc units in houses using Windows clunky software and weighing 5 times as much. How do they figure to sell to the 80% of planes that are sitting in hangars and on tarmacs not being flown? Develop a product that looks more like clunky desktop PCs and tell everyone it will save the GA world. Thats not R and D to serve all these owners not flying. 80% of the fleet doesnt need what they are going pedal at ridiculous cost.

        Put money in mogas at 3.50 to 4.00 gallon on airports and get the planes flying.

        • Trent says

          How did they figure out the affordable IPAD was a multi million unit profit potential back 10 years ago when it was being developed?
          The Newton was a complete failure. I bought one and liked it but it was too big and did not do enough.
          That product was not under S. Jobs while the iPad was. There were many that said the iPad would not find a market. So, Apple took a big risk.
          The answer to your question is Leadership. Leaders often make decisions that go against public opinion. Jobs often stated the consumers don’t know what they need until you give it to them. Nancy Palosi borrowed that for ObamaCare.
          I completely agree with your opinion that the planes that are not flying are grounded for many more important reasons than high priced fuel. If Shell would offer this fuel at current pricing, it will pull the tarps off of some planes but most will remain grounded. What it may do is to encourage new aircraft buyers to invest lots of money into a technology that now has a future source of fuel and money being spent on engine development could be used to reduce costs on existing engines.

          • Mark says

            Nail on the head….LEADERSHIP from EAA,AOPA, and FAA. NOT! Where there is no vision, the people perish….or in this case the guys with the planes sitting idle. Why keep giving fees to these people when they don’t hear us? You missed the point on one thing. If mogas is approved for STC , and can be in most of the GA fleet, and the airports got incentives somehow for getting the tanks on airports filled with 91 E0 distributed from terminals, at significantly less than 100ll prices, in many more areas than 1 or 2 per state, we could get there. As is the leadership we send money to is nothing but a road block.

  4. Mark says

    From October GAfuels blog “There is a surprising gem among the results of the AVweb Avgas Survey published on Oct. 6. This statement really caught my attention: “Nearly two thirds of respondents told us they think AOPA and EAA should get more involved in trying to get mogas on more airports.””

    Then I notice that this article is in general news section, not GAfuels section. As a mogas user it amazes me how the 80% of plane owners who could be STC’d for mogas are totally disregarded by “progress” in the GAFuel research area by development of 1 product, 100 octane lead free. Burning overpriced extreme high octane isnt necessary for me and many others, yet we continue to praise its development, and pin our hopes on the one thing that wont get all the planes in the air, overpriced fuel. Big oil, figure out how to lower the cost at GA airports and we might see more GA flying.

  5. Trent says

    As always good news for many bad news for a few. Until they ship and put a price on this, you won’t know which group you are in.
    Possible Winners: GA
    Possible Losers: Investors in other fuels hoping to “lead” the way.

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