Europe is slowly progressing toward the use of simultaneous non-interfering (SNI) approaches for helicopters at airports. This would improve rotorcraft access to busy airports while reducing the environmental impact, promoters of a dedicated research project believe. Further in-flight demonstrations are planned for next year, eight years after the first series of trials.
The SNI concept uses a satellite navigation-based IFR procedure with a steep initial approach slope to take the helicopter to a defined point in space. From there, the final approach to landing is visual. Researchers say the aim of the program is to provide sufficient separation from airliners while reducing helicopter noise.
The project, called Garden (GNSS-based ATM for rotorcraft to decrease noise), will continue through next year.
After designing procedures and defining a “regulation baseline,” the Garden team studied three cases: in the first, the approach was entirely non-interfering and used “strategic separation” based on horizontal protection areas; other cases, where the rotorcraft and the fixed-wing approaches were converging or parallel, had to rely on ATC.
Several operational issues that cropped up during the study–such as infringement of a no-transgression zone–require further investigation, but the team is already working on solutions.
ATM integration expert Philippe Rollet of Airbus Helicopter, a participant in the project, attributes the slow development of SNI approaches to the protracted deployment of the Egnos augmentation system. The SNI concept is being considered in the context of Sesar, Europe’s next-generation ATM, he added.