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Efforts to stop 100LL sales in California thwarted

By General Aviation News Staff · March 11, 2025 · 7 Comments

A judge has issued a tentative ruling denying efforts by the Center for Environmental Health to enforce a decade-old deal with California FBOs to stop selling 100LL when a “commercially available” unleaded avgas was on the market.

Alameda County Superior Court Judge Somnath Raj Chatterjee released his tentative ruling March 4, 2024, one day before he heard arguments in court.

In the tentative ruling, he denies the environmental group’s efforts to force FBOs to sell unleaded avgas only, saying that while an unleaded gas is “commercially available” — General Aviation Modifications Inc.’s G100UL — it is not “commercially feasible.”

In his ruling, the judge noted that while G100UL is “approved for aviation use” it requires an STC. That led him to determine that “STC approval concerns a modification from the original design rather than a general approval.”

“The Court as a matter of contract interpretation reads the word ‘approved’ as meaning approved by the FAA for general use and reads the phrase ‘commercially available’ as meaning both commercially available and commercially feasible,” the ruling continues.

In his ruling he notes that since G100UL has not gone through the FAA’s Piston Aviation Fuels Initiative (PAFI) program, ASTM, or the Eliminate Aviation Gasoline Lead Emissions (EAGLE) program, GAMI has not “demonstrated general approval.”

He adds that CEH’s efforts to require FBOs sell only that unleaded fuel are an attempt to force “a fundamental industry shift through the means of a consent decree, particularly here where regulatory bodies and industry groups are currently addressing the same issue — transitioning to the broad-based use of avgas with lower levels of lead. The court considers that aviation fuel is a regulated commodity. California legislation effective Jan. 1, 2025, states that airports may sell low lead aviation fuel until Dec. 31, 2030.”

Before the hearing on March 5, general aviation advocates raised alarms about the potential impact if CEH won its motion to force FBOs to only offer the new unleaded avgas.

The court action is “premature and counterproductive,” and could “cause undue harm to the general aviation community,” according to officials with the General Aviation Manufacturers Association (GAMA).

GAMA officials point to EAGLE as a “concerted effort” to “ensure that there is a safe and efficient transition to an unleaded future for piston-engine aircraft.”

“We have seen some key milestones reached to progress efforts, but there is still significant work needed before a full-scale transition can take place,” said Pete Bunce, GAMA president and CEO. “The CEH motion is based on a brand new high-octane unleaded fuel, which is currently available at just two California airports. Although the FAA issued an STC allowing for its use in airplanes, this is the only aviation fuel that has not been subject to a stakeholder consensus peer review process and does not have the endorsement for use by piston-engine and aircraft Original Equipment Manufacturers (OEMs) or other stakeholders, such as distributors and FBOs, due to lack of transparency and understanding of the new fuel’s composition and performance properties. Additionally, this fuel cannot be used in piston helicopters.”

“There are also questions and a need for additional information about materials compatibility and safety in both aircraft and fuel distribution infrastructure,” Bunce continued. “The general aviation industry is committed to supporting a viable unleaded avgas solution, but a forced and premature transition will not be in the interest of the aviation community or public in the long run.”

He added that there have been notices to the public from Cirrus Aircraft, Lycoming, Piper Aircraft, and Textron Aviation that “there are questions and potential concerns about the specified unleaded avgas product CEH is attempting to prematurely force on the piston aircraft community.”

“In addition to these warnings, aircraft manufacturers Aviat Aircraft, Diamond Aircraft Industries GmbH, Enstrom Helicopter Corp., Piper Aircraft Inc., Schweizer RSG, and Robinson Helicopters each submitted information to the court that stated the new unleaded avgas variant was not approved or supported by manufacturers for use in their models, given their companies lacked the information necessary to verify its safety and material compatibility,” Bunce said. “Additionally, several aviation trade organizations, including GAMA, submitted declarations to ensure the court was aware of the general aviation piston industry’s relevant perspectives.”

According to court documents, several individual aircraft owners in California also have filed declarations related to adverse issues potentially encountered by using G100UL, Bunce noted.

“Additionally, according to court documents, a California-based FAA Flight Standards District Office has initiated an investigation into some of these possible material incompatibility issues identified in several piston airplanes,” he said. “In the interest of aviation safety, GAMA calls for transparency and openness in a manner consistent with established industry practices for all transportation fuels — a broad stakeholder peer review assessment of new fuel property and performance data through the ASTM consensus standards process or similar — to include collaboration among fuel producers, chemical manufacturers, testing laboratories, fuel distributors and piston-engine aircraft and component manufacturers, etc.”

While G100UL underwent more than a decade of testing by the FAA, it has not been submitted to ASTM and GAMI officials say they have no intention of submitting the fuel to the organization, which develops international standards for products, materials, and services. 

Back in court, Judge Chatterjee concluded his tentative ruling by noting that it “will become the ruling of the court if uncontested by 4 p.m. the day before your hearing. If you wish to contest the tentative ruling, then both notify opposing counsel directly and the court at the eCourt portal found on the court’s website: Alameda.Courts.Ca.gov.”

A court date for the next hearing has not yet been scheduled.

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Comments

  1. Eric Fisher says

    March 12, 2025 at 5:12 pm

    California needs to just ban leaded fuel and get this nightmare behind us. Somehow this seems like the only answer..

    Reply
    • John Wells says

      March 12, 2025 at 7:20 pm

      If it burns up your engine, do you feel the same way North Dakota tried it in their fleet. They ran the engines exactly according to the manufacturers specifications.

      It damage their engines

      You still feel the same way about getting rid of leaded fuel?

      Reply
    • Catherine Vajtay says

      March 16, 2025 at 6:51 am

      REALLY??? The hell with the pilot, the hell with the plane, the hell with safety. How irresponsible and , I have to say it, idiotic, is that. I can’t believe you’re a pilot and fly airplanes with that attitude. On the other hand if you were kidding with that comment, you’re a rotten comedian.

      Reply
      • Catherine Vajtay says

        March 16, 2025 at 6:55 am

        This is a reply to E. Fisher. It posted in the wrong place

        Reply
  2. Raymo says

    March 12, 2025 at 5:29 am

    As much as I want to see G100UL succeed and become widely available, having it forced upon us by an environmental agency, that cares nothing about the facts around lead and the many studies that prove it is not a danger, is the wrong way to get it done.

    Reply
  3. JimH in CA says

    March 11, 2025 at 9:34 am

    California could see a large reduction in airport local lead emissions by requiring that Mogas be offered; a 91 octane, no ethanol gasoline. Most low compression engines can buy a Mogas STC, at low cost from the EAA.
    A large number of GA flights are local, low altitude training and proficiency flights.

    The higher usage, high performance aircraft, on longer, high altitude flights, will disperse the emissions over a much larger area, having a much smaller impact on the ground.

    My Cessna has had the Mogas STC for over 20 years, but I’ve never been able to find any no-ethanol gasoline in CA or nearby states.

    Reply
    • JS says

      March 12, 2025 at 6:43 am

      The fact that the state of California, as well as most of the rest of the country, will not support high octane MOGAS distribution (93 R+M/2) demonstrates that these people would rather have this as a political axe to grind as opposed to addressing what they claim to be an imminent danger (leaded fuel emissions). Nor do any of them show any interest in a reformulation of fuels to a much lower lead percentage in the fuels, which would be much easier to produce and would be better for the engines as well. Very few engines require the huge volume of lead present in 100LL, but we have been stuck with that for the last 50 years. Instead, we have this political “all or nothing” battle that goes nowhere. Alas, there is no common sense in politics.

      Reply

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