The purpose of this research is to develop a high-performance face gear set for aircraft. The geometrical design method of the face gear has already been proposed, and how to decide an effective engagement area under the design parameter has been clarified. A numerical example is presented based on the proposed method. The designed modified-tooth was processed by the Multi-Tasking machine. Finally, running test was performed at a pinion rotating speed of 970 rpm. The face gear set can be operated continuously at an maximum load torque 1390 N•m, without any trouble. The transmission efficiency reached 98.9% under maximum load torque.