An aircraft with a forward air intake may encounter the phenomenon of sudden flight stall during maneuvers at a high angle of attack, which reduces the aircraft's controllability and safety. In order to clarify the causes and essence of the aircraft's sudden flight stall phenomenon. In this study, based on the model of an aircraft with a forward air intake, we aim at the air flow rate around the air intake and adopt numerical simulation technology to conduct research. By studying the air flow rate, flow structure, and aerodynamic characteristics of the aircraft's air intake. It is found that during the aircraft's climbing maneuver the air flow rate of air intake will be decreased. This is the primary cause of the sudden flight stall phenomenon. On the other hand, with the increase of the angle of attack, the influence of flow separation on the air flow rate at the air intake also intensifies. This research is of great practical significance for designing the flight envelope of an aircraft with a forward air intake and preventing undesirable flight modes for pilots.

Cunjian Lyu. Investigation on the Flow Characteristics of Sudden Deceleration Phenomena in Aircraft with Forward-Mounted Air Intakes. International Journal of Frontiers in Engineering Technology (2026), Vol. 8, Issue 1: 7-13. https://doi.org/10.25236/IJFET.2026.080102.

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