Macroscopic fundamental diagram-based stability analysis of emerging low-altitude transport networks with multi-dimensional corridor configurations

Large-scale low-altitude air transport (LAAT) has the potential to extend urban mobility beyond ground networks, yet dense operations in constrained airspace may trigger congestion and unstable network states. This study develops a macroscopic fundamental diagram (MFD)-based framework to evaluate the efficiency, controllability, and stability retention of two-region low-altitude transport networks under different corridor configurations and operation modes. An airport-centered network comprising vertiports, intra-regional corridors, and inter-regional corridors is constructed, and a channelized distributed collision-avoidance model is introduced to capture safety-constrained aircraft movements. Linear, planar, and three-dimensional cruise corridor configurations are examined under cargo-only, passenger-only, and mixed cargo-passenger operations. The estimated MFD parameters are embedded into a two-region management model to quantify feasible inter-regional flow-control intervals, stable region (SR) areas, and their evolution with regional accumulation. Results show that upgrading the corridor structure from linear to planar and three-dimensional configurations increases network capacity and generally enlarges the controllable state space and weakens SR contraction. Quantitatively, for the mixed mode, the replication-based mean end-point relative change of SR area improves from - 4.1039 % under the linear corridor configuration to - 1.0768 % under the planar configuration and - 0.9204 % under the three-dimensional configuration. For the cargo-only mode, the corresponding values improve from - 2.3025 % to - 0.8071 % and - 0.3381 % , respectively. Robust factorial analysis confirms significant effects of corridor configuration, operation mode, and their interaction ( p < 0.001 ). The TCC configuration provides an additional statistically significant improvement over PCC for cargo-only and mixed operations, whereas the PCC–TCC difference is not statistically significant for passenger-only operation.