A federal review of helicopter safety around some of the busiest U.S. airports has revealed dangerous flying conditions at the Las Vegas airport.

The FAA said it was addressing several issues at Harry Reid International Airport in Las Vegas involving helicopters, including that tower controllers have not issued traffic advisories between returning air tour helicopters and airplanes, resulting in a routine lack of compliance with separation rules.

The Federal Aviation Administration says analysis in the wake of January’s crash between an Army helicopter and a passenger jet landing at Ronald Reagan Washington National Airport and has identified other airports where the risks of similar collisions are too high.