NASHVILLE (AP) — While Nashville International Airport hums to the tune of live music in a terminal filled with tourists and locals alike, this trendy gateway to Tennessee has quietly confronted an identity crisis.

Under a new state law, there is no clear agreement now about who's in charge of airport operations. The confusion comes at a time when the airport is booming, its annual passengers having more than doubled over the past decade to 21.8 million by the 2023 fiscal year.

The nonprofit Metro Nashville Airport Authority and state officials argue that a new group of state appointees has lawfully taken over the authority's board. But federal officials and the city contend the old board picked by Nashville's mayor still has power.

Both boards met at the same time last week across town from each other.

The dispute heads to a hearing Friday in a state court in Nashville.

Earlier this year, Republican lawmakers approved plans for the state to make enough appointments to control the airport's board starting in July. The change was among several passed by legislators seeking to curtail the power of the heavily Democratic city, whose metro council sunk a bid to bring the 2024 Republican National Convention to Nashville.

The city has filed suit against the state over the changes to the airport authority, which manages, operates, finances and maintains the international airport and a smaller one in Nashville. In the meantime, the authority installed the new board members on July 1, saying it can't defy state law without a court order.

Citing the Tennessee Constitution, the city's lawsuit argues the state violated home rule protections by singling out Nashville without requiring either a local referendum or a two-thirds vote of the metro council for the change.

The state responded that Nashville can't make its claims because the airport authority is independent of the local government.

City leaders, however, reached out and received input from the Federal Aviation Administration, which can veto certain changes to the airport's governance. The federal agency said it would keep recognizing the pre-July 1 board until a court decides the lawsuit.

Nashville Mayor John Cooper, a Democrat, has cried foul on the Republican change.

"Nashville's airport has grown very successfully over the years by the direction of this board, and that's unquestionable," Cooper said during a recent meeting of the board he selected. "Any state action is purely about politics."

Tennessee's situation isn't unprecedented. Due to FAA and court action, North Carolina's 2013 law to shift control of Charlotte Douglas International Airport from the city to a separate regional board never came to fruition. Mississippi's 2016 law to reconfigure Jackson's airport remains blocked by an ongoing legal challenge. Georgia lawmakers flirted with flipping the Atlanta airport's governance in 2019 but opposition sank the proposal.

Nashville officials say the state is upending an airport board without complaints about its performance, even during a time of extensive expansion.

In the 2023 budget year, the airport unveiled a new lobby, added more restaurants and live music, opened an additional parking garage and made progress toward an onsite hotel. The airport hosts country, jazz and bluegrass concerts in its terminals and exhibits the work of local artists.

The facility has endured growing pains, too, marked by passenger pickup lines sometimes stretching well past a nearby interstate exit.

Lawmakers passed the change despite predictions in April by former FAA official Kirk Shaffer that it would create competing boards in "a messy and costly stalemate that damages all involved," possibly jeopardizing federal grant money.

So far, the fight is largely unfolding in court filings. The city says lost grant money could halt projects to accommodate more flights, spurring cancellations and delays. The state and the airport authority argue the grants aren't in jeopardy. The authority said Nashville officials are making "sky-is-falling" exaggerations.

Republican lawmakers contend the state deserves more say over the growing airport because of its regional impact. House Speaker Cameron Sexton said lawmakers created "the legally sanctioned board."

As an intervenor in the lawsuit, the airport authority has remained neutral on whether the new law is unconstitutional. Updates to the FAA have never resulted in the federal agency directing the authority to stop following the state law, while even worse disruptions would result from an order to temporarily return to the preexisting board, the authority wrote.

The state-majority board met at the airport on Wednesday, conducting standard-fare business on contracts and reports. At the same time, the members of the mayoral-picked board gathered in city hall, reiterating that the FAA still acknowledges them while criticizing the state law and approving an outside attorney hire.

In a letter to the Nashville community at large, the authority's CEO has acknowledged the "frustration and confusion" caused by the dispute. But he said the authority is responsible for staying legally compliant.

"As an airport authority, we do not take political positions," airport authority President and CEO Doug Kruelen wrote in the July 6 letter.