An initial Safety Concept for Segmented Independent Parallel Approaches

Kurzfassung

Air traffic is forecast to grow significantly in the coming decades. Therefore, airport capacity and environmental issues, especially noise mitigation, are major challenges facing aviation. One possible solution to these challenges is the development of new operational procedures based on satellite navigation. Ground-based augmentation systems (GBAS) as well as the concept of required navigation performance (RNP) have the potential to assist in the design of more flexible, noise-mitigating procedures while maintaining the airport capacity. In contrast to the technological possibilities, according to ICAO standards, only straight, precision approaches currently meet the stringent requirements for independent parallel runway operations. Therefore, the full operational potential of both GBAS and RNP cannot be realized under existing standards. To pave the way for the implementation of more flexible, noise-mitigating approaches at major hub airports this paper presents an elementary safety concept for segmented independent parallel approaches. Developing an elementary safety concept for this setup, the paper is structured as follows: After a presentation of the approach layout, the differences between the proposed design and current ICAO guidelines are described. The critical safety issues of the new approach procedure are evaluated with a focus on so called blunders, aircraft deviating from their intended approach track towards the parallel track. After identifying major safety challenges, a revised concept for monitoring the independent approach paths is developed. A design concept for normal operating zones (NOZ) and the non-transgression zone (NTZ) is presented, taking into account new technologies for approach monitoring and the characteristics of the curved trajectory. Based on the experiences of independent parallel ILS approaches and considering the characteristics of RNP and GBAS, the procedure is finally compared to a target level of safety.