The Swiss Greener Wave project has combined the collective expertise of Skyguide, Swiss International Airlines and Zurich Airport to improve arrival efficiency and cut CO2 emissions.

Traditionally, a number of Swiss International Airlines long-haul flights arrived at Zurich Airport in the early morning, creating a “queue” of sorts in the air as they waited for their chance to land once the curfew was lifted each day. This collaboration has created a system that assigns a 4-dimensional slot at a pre-defined point and time between 20 to 120 nautical miles away from Zurich Airport. Flight crews can then adjust their speed during the cruise part of the flight to arrive at the assigned point exactly on time, without the need for unnecessary delaying of arrival.

This system allows approaching aircraft to fly a more continuous, fuel-efficient descent. The new focus on airport arrival efficiency has led to modifications of the standard arrival procedures for Zurich Airport, which has decreased track miles flown and cut CO2 emissions. In fact, half a tonne of CO2 emissions per flight are now able to be avoided through the collaborative project.

The improved air traffic operation has led to an increase in efficiency and capacity at Zurich Airport without any changes to infrastructure. Zurich residents have also enjoyed a significant decrease in early morning noise due to the near elimination of extra air traffic controller actions and aircraft holding. The Greener Wave project has paved the way for other research and development initiatives in Europe (for example Fairstream and iStream projects) to validate this new concept of operations in different environments.