A smarter way to address wake turbulence separation can increase runway capacity, tests conducted by Eurocontrol—the Brussels-based organization in charge of air traffic management (ATM) in Europe—and Lufthansa Aviation Training have shown.

The idea is to have the lighter-wake category aircraft flying above the approach profile of the preceding, heavier aircraft. A secondary runway aiming point (SRAP) is therefore created. According to the promoters of the concept, runway throughput could be increased by up to 5%.

The effort has been led by Eurocontrol under Europe’s Single European Sky ATM Research (SESAR) 2020 program for ATM research and has involved trials on Airbus A319 full flight simulators operated by Lufthansa Aviation Training. Sessions were organized for 12 two-pilot crews, each flying 14 simulated approaches at Germany’s Munich Airport.

The SRAP was located 1,100 m (3,600 ft.) after the primary runway threshold. A precision approach path indicator was set up. In a first variant of the concept, all lights were illuminated, meaning threshold and approach lights of both the primary and secondary aiming points remained switched on. In the second variant, lights were illuminated for only one aiming point at a time.

A variety of visual conditions were tested, ranging from CAVOK (perfect) to 2,500 m visibility. Video recordings were accompanied by the monitoring of flight parameters such as position and vertical speed. Approach and landing performance could thus be assessed.

There is an environmental benefit to using a SRAP. The noise contour of the aircraft on approach moves towards the airport, reducing noise. To maximize benefits, the approach glide slope to the SRAP could be an increased glide slope, at 3.5 degrees instead of the usual 3 degrees. Both were simulated.

Eurocontrol deems the trials successful. A questionnaire was given to the pilots, asking them about the acceptability of the concept. The initial result of the answers’ analysis is favorable, according to Eurocontrol.

Final development will begin in January 2020. Eurocontrol hopes to bring a validated SRAP concept to maturity by 2023, meaning a deployment phase could then be plotted.

            Thierry Dubois, thierry.dubois@aviationweek.com