The aerodynamic stability of the peripheral and supra-platform blading sections of the aircraft gas turbine engine (AGTE) fan stage was examined as a single elastic system using the database description and analysis of experimental aerodynamic influence coefficients. The computing circuit of those sections is presented. The phase angle \({\theta }_{y\alpha }\) , which varied between translational and angular blade displacements, is shown to induce the rotation of vectors of forces and moments responsible for crossing coupling between these motion components, leading to the loss of dynamic blading stability. The critical reduced vibration frequency Kcr against the phase angle \({\theta }_{y\alpha }\) is given for the vibration blading modes with different numbers of nodal diameters (1–8) at the angles of attack of 10–15° that determine the domain of possible subsonic stall flutter. The effect of aerodynamic blading coupling on its aerodynamic stability was viewed for forward and backward-traveling strain waves at different nodal diameters. For the peripheral blading section at forward-traveling strain waves with the angles of attack > 5°, in contrast to its supra-platform section, the critical reduced vibration frequency is demonstrated to greatly increase due to an essential growth of the aerodynamic bladed disk coupling. It is determined that for backward-traveling strain waves, subsonic flutter is possible at the angles of attack >10° and nodal diameters of 4–6. On the example of the peripheral fan blading section, the effect of changing the number of blades on its aerodynamic stability is discussed. A decrease in the number of blades in the fan blading leads to an increase in its aerodynamic stability for all angles of attack, regardless of the number of nodal diameters.
