Optimizing a Collision-Avoidance System for Closely Spaced Parallel Operations

Abstract

The traffic alert and collision-avoidance system has been mandated worldwide to protect against aircraft midair collisions. One drawback of the current traffic alert and collision-avoidance system design is limited support for closely spaced parallel runway operations. The traffic alert and collision-avoidance system alerts, too frequently, leading pilots to often inhibit resolution advisories during approach. Research is underway on the Airborne Collision Avoidance System X, which is a next-generation collision-avoidance system that will support new surveillance systems and air traffic control procedures. The Airborne Collision Avoidance System X has been shown to outperform the traffic alert and collision-avoidance system for en route encounter scenarios. However, the design parameters that are tuned for the en route environment are not appropriate for closely spaced parallel landing operations. One concept to allow for closely spaced parallel landing operations is a procedure-specific mode of the logic that reduces the nuisance alert rate while still providing collision protection. This paper describes the application of surrogate modeling for the purpose of tuning Airborne Collision Avoidance System X for parallel landing operations. The performance of the tuned system is assessed using a data-driven blunder model and an operational performance model. The tuned Airborne Collision Avoidance System X logic is found to equal or outperform the traffic alert and collision-avoidance system for each model in terms of both safety and operational suitability.