A single-engine Piper sits on the ramp at the Jefferson City airport, a few minutes from the Missouri Capitol. On paper it belongs to a limited liability company in Montana — a state with no general sales tax and no property tax on aircraft. It is one of at least 16 planes parked at Missouri airfields but registered to Montana shell companies.

Missouri's county assessors are supposed to find planes like that and tax them, the same way they tax your car. They are having a harder and harder time doing it.

Bob Onder wrote a provision that would make it harder still.

The Missouri Independent's Jason Hancock reported in July 2026 that Onder — a first-term Republican from St. Charles County, a physician, and a licensed pilot — authored language that would bar state and local governments from using aircraft-location data to identify planes "for the purpose of obtaining revenue" from their owners.

Asked by the Independent whether he owns or leases a private aircraft, Onder did not respond.

What the data is, and why it matters

Since 2020 the FAA has required most aircraft to broadcast a signal called ADS-B — Automatic Dependent Surveillance-Broadcast. It continuously transmits a plane's identification, altitude, speed and heading. It exists so planes don't hit each other.

Tax collectors found a second use for it. Match the broadcast ID against the national aircraft registry and you can attach a name and an address to the plane sitting on the ramp. A small industry now packages that data and sells it to revenue agencies.

It works. In Los Angeles County, assessor Jeff Prang told Politico his office used the data to identify 1,000 aircraft it hadn't been taxing — a combined assessed value of $3.5 billion, or roughly $35 million a year at California's rate. Prang's summary, quoted by the Independent: "Private aircraft owners go to great lengths to hide their aircraft from us." Without the data, assessors are back to driving to airfields and counting planes by hand — and owners who know the schedule "might fly their planes out of state."

Onder's provision would turn that off.

The vehicle: a bill written after 67 people died

Onder introduced his language as a standalone bill in June 2025, the PAPA Act — Pilot and Aircraft Privacy Act. It went to the Aviation Subcommittee and sat there.

Then it became Section 105 of the ALERT Act, the House's response to the January 2025 midair collision between an Army Black Hawk and an American Airlines jet near Reagan National Airport. Sixty-seven people were killed. The National Transportation Safety Board produced 50 safety recommendations, and the House built a bill around them.

Onder's tax provision rode along inside it. The House passed the package in April, 396–10.

The Senate's competing bill, the ROTOR Act, contains nothing comparable. So the question of whether county assessors can keep using flight data to find taxable airplanes is now one of the items to be settled when the two chambers reconcile — attached to a safety bill almost nobody would vote against.

"A clear, nationwide standard"

Onder frames it as privacy. He says third parties have "taken advantage of this data to impose and collect exorbitant third-party landing fees and frivolous lawsuits" against general aviation, and describes himself as "a pilot with years of experience" using the system.

But the language is wider than landing fees, and its supporters said so themselves. House Republicans wrote in their own report on the bill that the provision would "establish a clear, nationwide standard, preempting any future state, local or tribal law."

Tax officials tried to fix it before the vote:

• The California Assessors' Association, a nonpartisan body of county officials, wrote to Onder and other committee members in March pointing out that the bill never defines the "fees" it restricts, that it could be read to reach property taxes, and asking that the language be narrowed to airport charges.
• Alabama's revenue commissioner estimated the provision could cost his state, its counties and its municipalities more than $18 million a year.
• Rep. Shomari Figures, an Alabama Democrat, offered an amendment in committee to preserve state and local governments' ability to keep using the data for tax collection. It was not adopted.

And the objections weren't only from tax collectors. At a June 23 Senate aviation subcommittee hearing, Todd Hauptli, president of the American Association of Airport Executives, testified that Onder's proposal "would preclude airports from their ability to use ADS-B for fee collection purposes." Airports use those fees to pay for safety projects. Pilots who switch off their transponders to dodge the fees — as some have threatened to — make flying less safe.

Sen. Jerry Moran, the Kansas Republican chairing that hearing, put the point plainly: the fees are "already required to be paid." Nobody is arguing the money isn't owed. The fight is over whether anyone can find out who owes it.

The money

The Aircraft Owners and Pilots Association is the nation's largest pilots' lobby. A PAC connected to it gave Onder $5,000 in late September — after he introduced the bill.

AOPA also backed the separate 2024 federal law that lets private aircraft owners keep their names and addresses out of the public registry. That law is why Missouri's State Tax Commission stopped giving county assessors a county-sorted list of aircraft this year: the Department of Revenue no longer supplies the underlying data.

Two laws, two years, one result. The 2024 law hides who owns the plane. Onder's provision hides where it flies. Together they close both doors.

Chrissy Gillis, the Putnam County assessor and president of the Missouri State Assessors Association, told the Independent what that already feels like on the ground:

"With the new regulations and the ability to hide their information, it has made this process very difficult to appropriately determine what aircraft is registered within counties for assessment purposes."

The State Tax Commission's own chief counsel conceded that if an owner leaves a plane off a personal property declaration and has had identifying information redacted from federal records, "the assessor may not be able to identify certain aircraft as property which is assessable in that county."

Who actually pays

Aircraft in Missouri are taxed at the county level as personal property. The bill is collected for schools, libraries and local government.

Missourians pay personal property tax on their cars every single year, and the county knows exactly where they live — the plates are on the car in the driveway. For a $3.1 million turboprop flying out of Spirit of St. Louis Airport, the same obligation can turn on paperwork filed 1,200 miles away, and on whether anyone can establish where the aircraft actually sits. That second part is what Onder's provision takes away.

How much money is at stake if Onder's provision becomes law? Nobody in Missouri state government can say. Asked how much the state collected last year in sales and use taxes on aircraft purchases, a Department of Revenue spokesman told the Independent: "The department does not specifically track this information."

So the honest summary is: a congressman who flies wrote a rule that helps people who fly, inside a bill about a crash that killed 67 people, and neither he nor the state can tell his constituents what it costs them.

Not the first time we've seen this

The private-aviation angle keeps recurring. In Pennsylvania, Rob Bresnahan sells himself as a blue-collar everyman while spending more than $23,000 on a single private jet flight and quietly flying his own helicopter. The difference here is that Onder didn't just take the flight. He wrote the law.

Source

"Missouri Republicans push change that would make it harder to collect taxes on private planes" by Jason Hancock, Missouri Independent, July 10, 2026. Bill text from congress.gov. Photo: Rudi Keller / Missouri Independent.