The US FAA has issued guidance for air traffic controllers to manage requests by pilots and airlines stemming from the Department of Transportation's (DOT) new three-hour tarmac rule starting 29 April.

As part of the DOT's Enhancing Airline Passenger Protections rule, published in late December, carriers at medium and large hub airports must develop a contingency plan that allows for aircraft to return to the terminal if stranded on the airport surface for more than 3h after landing or leaving the gate.

A likely unintended consequence of the rule will be higher workload for air traffic controllers.

According to a notice issued by the FAA to air traffic organisations on 6 April, the agency's system command centre as well as affected en route and terminal control facilities will have to develop and review complex procedures for handling requests related to tarmac delays and reporting aircraft that violate the rule.

In particular, controllers will be tasked with determining whether having an aircraft return to the terminal based on the 3h rule will cause a "significant disruption" of service at the airport, a finding that negates the rule and allows the aircraft to remain on the tarmac.

FAA has outlined the criteria controllers must use to determine significant disruptions caused by the new tarmac regulations. Guidelines issued to controllers include determining if the aircraft returning to the gate would keep airborne traffic in a holding pattern for 15 minutes or longer, if an aircraft that is returning to gate is using an active taxiway that would cause delays in excess of 15 minutes and if allowing a delayed aircraft to taxi back to the gate would place other aircraft in jeopardy of violating the new rule.

When notified that an aircraft has exceeded the 3h rule, controllers are then required to assemble an incident file including the flight plan of the aircraft, delay information included in its pre-departure clearance, phone calls to an airline's operation centre, audio files of the transmissions between the aircraft and controllers, position logs, radar data and other information. The records must be kept for one year, says the FAA.

Source: Air Transport Intelligence news