FedEx could see a double-digit increase in capacity at its Memphis hub after Nov. 1 when new FAA wake turbulence recategorization (RECAT) rules go into effect.

The new rules are the result of 10 years of study by a “WakeNET USA” working group that includes industry, the FAA, Eurocontrol, NASA and others. Following Memphis, the FAA says RECAT will go into effect at other airports in the U.S. between 2013 and 2014.

An FAA safety alert for operations issued Oct. 18 outlines the changes. Currently, the agency uses six wake turbulence separation categories based primarily on aircraft weight, but with RECAT, categories and required separations will now be based on weight, certified approach speeds and wing characteristics, “along with special considerations given to aircraft with limited ability to counteract adverse rolls,” says the FAA.

Categories are labeled A-F, with A being the largest (Airbus A380 and Antonov An-225) and F the smallest (includes the Embraer EMB-120 Brasilia and the Beechcraft 1900).

“For the FedEx fleet mix, what we will see on the line is approximately a one-mile reduction in the separation that occurs today,” says the master executive council of the FedEx Air Line Pilots Association chapter in a recent letter to members.

“When spaced out over the size of our arrival and departure banks, this possibly could result in almost a 20% increase in capacity,” the union adds.

Additional benefits, according to the pilots union, will include shorter-duration final approaches to the airport and the associated reduction in fuel burn and emissions, improved schedule reliability, less pilot fatigue and better delay mitigation.

“When thinking a bit further ‘outside the box,’ getting aircraft in and out faster can reduce the down time while hub turning and give us more time at the hotel,” the union says. “Last package pickup at outstations could occur later, increasing our customer base through improved customer service.”