Wake turbulence behind large aircraft presents challenges to following aircraft, most critically in takeoff and landing. Air traffic managers assign wake turbulence categories (WTC) to aircraft by size, and release follower aircraft for takeoff or landing only after the wake separation time for the lead aircraft has passed.

Eurocontrol is working to improve this, by basing wake separation times not on WTC, but on aircraft types. The objective is to improve runway throughput at high-traffic airports by making wake separations specific to the lead and follower aircraft types. Each type pair will have its own wake separation time; this will normally be shorter than today’s WTCs, but in some cases will be longer. The net result will be higher runway capacity and higher safety.

For this Static Pairwise Wake Separation for Departures (S-PWS-D) project, the simulation run on AXIS ATR600 full flight sims to gather and refine data on turbulence behaviour. This data is now being evaluated by Eurocontrol, towards finalization of the safety case and submission for regulatory approval.