A Sequential Planning Framework for the Operational Reality of Interacting Air Traffic Flow Regulations and Traffic Flow Programs
Thinh Hoang, Daniel Delahaye
TL;DR
This paper tackles regulation-space planning for Air Traffic Flow Management to curb regulation cascading by modeling sequential regulation design as a finite-horizon decision process. It introduces RegulationZero, a hierarchical Monte-Carlo Tree Search framework that uses a Regulation Proposal Engine and an FPFS-based allocator to iteratively build and evaluate sequences of flow-level regulations, maintaining compatibility with existing slot-allocation systems such as CASA and RBS++. The method leverages hotspot targeting, flight footprints, and community-detection-based grouping to propose high-leverage regulations, with PUCT-driven selection and KL-regularized exploration guiding the search. Empirical results on large-scale European data show RegulationZero delivering robust, scalable improvements over a greedy policy and outperforming a trajectory-space simulated annealing baseline at longer planning horizons, while delaying only a minority of affected flights. The work demonstrates the potential of regulation-space planning to reduce RC-induced volatility and highlights practical considerations for realism, expert knowledge integration, and future deployment in operational ATFM contexts.
Abstract
Air Traffic Flow Management (ATFM) traffic regulations are being increasingly used as rising demand meets persistent workforce shortages. This operational strain has amplified a critical phenomenon that we call \emph{regulation cascading}: the compounding, non-linear interactions that occur when multiple regulations influence one another in unpredictable ways. As the number and complexity of regulations grow, cascading effects become more pronounced, undermining the network operator's ability to protect sectors reliably. To address this challenge, we introduce RegulationZero, a sequential planning framework that natively operates in the regulation space, optimizing over ordered sequences of flow-level regulations that remain fully compatible with existing slot-allocation systems such as CASA and RBS++. At its core, the method employs a hierarchical Monte Carlo Tree Search (MCTS) that first samples congestion hotspots and then selects candidate regulations synthesized by a local proposal engine. Each proposal is evaluated by a fast First-Planned-First-Served (FPFS) allocator to estimate its reward, with these feedbacks guiding the subsequent MCTS exploration.
