RECAT: a new framework for more “turbulent” aircraft

The RECAT-EU* project classifies aircraft into six categories by weight, thereby allowing arrival and departure rates to be increased in complete safety at the largest international airports. The project was launched in 2015 at Roissy airport and the initial results are promising.

Before RECAT-EU, aircraft were classified into three categories, plus one category for the A380 alone. These allowed the aircraft to be differentiated on the basis of their maximum take-off weight and consequently on the basis of their wake turbulence, which is proportional to take-off weight. The International Civil Aviation Organization (ICAO) applies separation minima between each aircraft on arrival and departure which are dependent on their category.

“The project subdivided the heavy and medium categories of the old system in order to reduce the ICAO separations ahead of the aircraft most resistant to turbulence and behind those which generate less turbulence” explains Vincent Treve, the person responsible for RECAT-EU at the EUROCONTROL Experimental Centre (EEC). Flight tests and visual measurements have thus resulted in the emergence of six new classes of aircraft.


Support for pilots and controllers

Thanks to changes in the French regulations in November 2015, Roissy-Charles de Gaulle (CDG) airport was able to envisage the application of the new RECAT-EU classification. A preliminary safety study was, however, necessary in view of the new technology to be introduced (radar interface, preparation of the training simulator and monitoring system, information for pilots, etc.).

Moreover, such a major change of practice for pilots and air traffic controllers could not have been envisaged without technical and human support. According to Vincent Treve,“RECAT-EU imposes new separations, new categories and a larger number of combinations on controllers. As for pilots, they are closer to the aircraft ahead of them, without necessarily knowing why.”

The aeronautical information was amended and simulator sessions were offered to the senior pilots and instructors of the main airlines using Roissy-CDG airport. In parallel, the EEC put in place a special training cycle for controllers.


More aircraft and greater safety

Since the night of 22 March 2016, the controllers at Roissy-CDG airport have been applying the new RECAT-EU categories to arriving flights. “These new separations generate an increase of three to four movements an hour for each runway.” Thanks to RECAT-EU, CDG airport should be recording 82 arrivals an hour by 2020 compared with the current figure of 73.

* RECAT-EU: European Wake Vortex Re-categorisation