Mesa's Falcon Field air pollution under attack

Gary Keller has a problem with Falcon Field Airport in northeast Mesa.

“The lead emissions from general aviation planes from this airport are the worst in the U.S.,” he alleged. “This lead is poisoning the children and the water supply.”

The environmental advocate is not alone in this stance.

Change.org has a petition signed by over 2,000 people protesting the lead exposure from the city-owned airport and also the excessive aircraft noise. According to the petition, the aviation fuel spews out toxic lead into the air during every flight.

Lead exposure endangers health, including causing severe damage to the brain and central nervous system, seizures and death, according to the U.S. Environmental Protection Agency.

Earthjustice ranked Falcon Field No. 15 in the country and No. 4 in Arizona on its Top 100 Lead-Polluting Airports list. Earthjustice is a nonprofit public interest environmental law organization.

Mesa Gateway Airport, owned and operated by Mesa, Gilbert, Apache Junction, Queen Creek and the Gila River Indian Community, is right behind Falcon Field at No. 5 on the list. The top offender in the country was Phoenix Deer Valley Airport in Phoenix.

However, the Federal Aviation Administration is taking steps to phase out by the end of 2030 leaded aviation fuel used by piston-engine aircraft, which typically carry two to 10 passengers. Large commercial passenger planes use jet fuel, which is kerosene-based.

The federal agency in January released for public comments a 76-page, draft plan to transition to unleaded fuel, accepting feedback until March 13.

This will affect every actively used spark-ignition piston-engine aircraft, pilot, owner, fixed-base operator such as a business on site that sells fuel and the entirety of their supporting infrastructure, the plan said.

Affected aircraft include the Cessna 172, the Curtiss C-46, the Robinson R44 helicopter, light-sport aircraft and ultralight vehicles equipped with piston engines.

The 15 flight schools at Falcon Field, a bone of contention with the Mesa petition, primarily use piston-engine aircraft.

According to the FAA, flight schools often carry out high levels of activities near the airport such as touch-and-go operations, which concentrates the area where emissions are released.

Such concentrated emissions may extend more than half a mile from the end of the runway, it said.

The draft plan provides a framework for the transition and describes four phases of transition, anticipated timelines, fuel-authorization pathways, and steps that airports, pilots and aircraft owners will need to consider as unleaded fuels continue to enter the market in the coming years, according to the FAA.

For example, the first phase will address two prerequisites to the changeover – what are the approved fuels, and how do the fuels compare?

The second phase will allow for time for the market to gain experience with the various unleaded fuels and phase three is the national transition in all states, except Alaska, which comes at the end of 2032 for phase four.

The agency launched the Eliminate Aviation Gasoline Lead Emissions initiative or EAGLE in 2022, a government-industry partnership.

Mesa released a statement in support of moving away from the use of AvGas 100 LL, a high-octane fuel, which contains tetraethyl lead to boost octane levels, prevent engine knock and ensure safe, high-compression engine performance.

“Falcon Field Airport is monitoring the FAA’s draft transition plan and supports efforts that improve safety and reduce environmental impacts while maintaining reliable general aviation operations,” it read. “Aircraft fueling services at Falcon Field Airport are provided by private sector businesses. The City is committed to helping these businesses promote the transition from low leaded to unleaded fuel to airport customers when the unleaded fuel becomes available for purchase in the Phoenix market.”

Fall 2025 data showed about 222,000 spark-ignition piston engine aircraft registered with the FAA, of which 175,000 were estimated to be actively flying, the plan said.

The FAA is expected to select by spring 2027 the unleaded fuel that will be used. As of September 2025, there were three candidate unleaded fuels at “various stages of obtaining FAA approvals or authorizations, deployment to, and use of new unleaded fuel(s),” according to the agency.

According to the FAA, the most significant risk to the plan is the schedule. Should there be any delay in four critical areas – fuels production, fuel infrastructure, fleet readiness and supporting policy – it will put “the entire transition timeline at risk,” it said.

Although the U.S. has made strides in reducing lead emissions such as with a full ban by 1996 on leaded fuel use for vehicles and commercial planes, small aircraft “are the largest remaining aggregate source of lead emissions to air in the country,” the EPA said.

In 2020, approximately 427 tons of lead were emitted by engines in piston-powered aircraft, which constituted 69% of the annual emissions of lead to air in that year, the EPA added

The EPA estimated that among the approximately 20,000 airports in the U.S., airport lead inventories range from 0.00005 tons per year to 0.9 tons per year.

At the state level, the environmental agency estimated lead emissions from piston-engine aircraft range from 0.3 tons in Rhode Island to 50.5 tons in California.

At Falcon Field, 424,112 flights were recorded for 2024, according to the latest data from the city.

So far on social media, pilots for the most part voiced opposition to the plan.

“So is FAA going to cover the cost to convert/modify all those plane engines to run on other fuel?” one man wrote while another called it “a plan to bankrupt private aviation and small airplane owners.”

Another said, “All arbitrary deadlines based on zero data.”

“The amount of lead pollution is almost negligible,” the pilot continued. “It has never even been able to be detected in exhaust directly behind a running engine. “The fuel market of AvGas is a tiny percentage. Yet they wish to endanger aviation and cause a lot of longevity problems based on a theory. No unleaded has proven equal to 100LL.”

Mesa took ownership in 1948 of Falcon Field, a former World War II pilot training base. It is a general aviation reliever airport that serves various uses, including for business, recreation and fixed-wing and helicopter flight training.