The ongoing White House construction contributed to radio problems that kept air traffic controllers from hearing calls warning that President Donald Trump’s helicopter was getting ready to take off, so they cleared an airline jet to take off just as Marine One took to the air earlier this month, federal investigators said Thursday.

The week before the president’s helicopter got too close to that Envoy Air jet near Ronald Reagan Washington National Airport, air traffic controllers and Marine One pilots met to discuss controllers not receiving the standard three-minute warning call ahead of Marine One flights, according to a preliminary report from the National Transportation Safety Board. They made plans to relay radio calls through someone else if there were future problems but that was also unsuccessful on the day of the Aug. 4 incident.