WASHINGTON ( CNN ) -- The Federal Aviation Administration Tuesday ordered a nationwide halt to `` opposite direction '' runway operations , in which planes arrive on runways in one direction and depart in the other , as the result of an investigation into last week 's incident at Reagan National Airport involving three planes which came dangerously close . FAA Acting Administrator Michael Huerta ordered the temporary halt , saying the agency discovered it has `` no standard protocol '' for switching from a one-way runway traffic pattern to the less common two-way pattern . The lack of a standard protocol likely contributed to the July 31 mishap , he said . During last week 's incident , a southbound US Airways regional jet arriving at Reagan came in close proximity to two northbound jets taking off from the airport . At their closest , two planes came within 0.82 nautical miles , less than the required 3.0 nautical miles . In a memo released Tuesday , Huerta repeated his initial statement that the aircraft were never on a head-to-head collision course . And he again blamed the mishap on a miscommunication between the Potomac TRACON , a regional radar facility , and managers at Reagan 's control tower . But the investigation has altered one key understanding of the incident . Department of Transportation and FAA officials originally told reporters that the misunderstanding occurred as controllers `` flipped '' the direction of the airport , switching all traffic from a northbound direction to a southbound direction . Now Huerta says the regional TRACON controller intended to change the direction of only the arriving aircraft , allowing `` opposite direction '' traffic on the runway . Controllers sometimes allow two-way traffic to comply with noise restrictions or to accommodate cargo operations , he said . Takeoffs and landings are staggered to avoid collisions . While changing from one-way traffic to two-way traffic encompasses many of the same procedures as flipping an airport , `` there is no standard protocol in place , '' Huerta wrote . `` We believe this contributed to the miscommunication . '' Huerta said he is halting two-way runway traffic `` out of an abundance of caution , '' and that the FAA expects to have standard procedures in place within a month . Huerta said the Reagan incident also raised the issue that the FAA 's front-line managers are managing administrative tasks in addition to overseeing tower operations . `` We need to be sure that they are solely focused on the operations in the facility and not handling administrative duties '' during busy times , he wrote . The 2 p.m. incident involved three aircraft : Chautauqua Airlines 3072 , Republic Airlines 3329 and Republic 3467 . All three aircraft were operating as US Airways Express . All reached their destinations safely .
Lack of protocols for switching runway traffic patterns led to temporary halt , FAA says . In incident at Reagan airport , southbound plane got too close to two northbound planes . FAA : Planes were never on head-to-head collision course .