Effects of surveillance failure on airborne-based continuous descent approach

Abstract

For higher density operation in terminal manoeuvring area, Airborne Surveillance
Application System (ASAS) is seen as a promising option in the future air traffic management
(ATM). One idea of recent interest in ASAS application is Interval Management (IM), which is
expected to support energy-saving arrivals, commonly referred as Continuous Descent Approach
(CDA). The questions are how the IM application achieves safety and capacity in the CDA environment,
and how to identify any potential emergent behaviour that should be taken into
account in the operation design. The motivation for this study is the need to properly understand
the nominal and non-nominal behaviour of many aircraft when the ASAS application is applied to
the CDA environment.
For this purpose, this study has conducted a preliminary safety assessment of the ASAS speed
control for multiple trailing aircraft in CDA operation. This article focuses on ASAS surveillance
failure as one of the critical events during flight. Using Stochastically and Dynamically Coloured
Petri Net (SDCPN), ASAS core components and their interactions are modelled. Through Monte
Carlo simulation via the SDCPN models, the impact of the ASAS surveillance failure on the
airborne-based CDA operation is assessed.