A coalition of U.S. sports leagues is urging lawmakers not to reverse a federal law banning flights over sports stadiums.

In a letter sent on Tuesday, representatives from the NFL, the MLB, NASCAR, and NCAA expressed their concern about section 813 of the House version of the Federal Aviation Administration (FAA) Reauthorization Act, saying the proposal “would establish a broad and complex waiver program that would permit countless aircraft to fly near and over stadiums during games.” 

League officials said that the proposed measure would put millions of sports fans at risk, and that the current ban provides necessary safety and security protections against potential threats. 

“The FAA first established flight restrictions over large stadium sporting events immediately following the terrorist attacks of September 11, 2001, in response to concerns about terrorists using aircraft as weapons,” the sporting league officials wrote in their letter, obtained and published by Punchbowl News. 

“Congress subsequently twice codified and strengthened these restrictions, providing specific criteria for aircraft operations permitted within the flight restricted area,” the letter reads, with officials also noting that lawmakers turned down a similar waiver program proposal in 2003. “Section 813 would effectively eliminate the specific criteria and replace it with an openended waiver program.”

The House is set to take up its version of the must-pass bill on Wednesday.

League officials said in their letter that the current rules enhance the safety and security of large stadium events and minimize disruption of the National Airspace System (NAS). They noted that airspace over stadiums with a seating capacity of 30,000 people or more is closed to all aircraft from one hour before until one hour after a major sporting event.

“Having devoted substantial resources to secure our stadiums on the ground, we regard the stadium flight restriction as essential to safeguarding the airspace overhead,” the letter reads. “We believe section 813 complicates the airspace over stadiums, compromises public safety and security, and courts potential disaster.”

“We, therefore, urge you to uphold current law and maintain existing flight restrictions that protect the safety and security of millions of fans who attend large stadium sporting events every year,” the letter concluded.