Propulsion system with downstream section having deformable shape-memory material and actuators extending in different consecutive angular sectors

A propulsion system for an aircraft, comprising:

• at least one rotor and a nacelle fairing extending around said at least one rotor with respect to an axis of rotation of said rotor, the nacelle fairing comprising an upstream section forming an inlet cross-section of the nacelle fairing and a downstream section, a downstream end of which forms an outlet cross-section of the nacelle fairing;
• and
• wherein the downstream section comprises a radially internal wall and a radially external wall made of a deformable shape-memory material and in that the downstream end forming the outlet cross-section comprises a plurality of pneumatic or hydraulic actuators, each actuator of the plurality of actuators being independently actuatable and extending in different consecutive angular sectors about said axis of rotation, and configured to deform in a direction which is radial with respect to the axis of rotation and which is angularly centered with respect to the angular sector over which each said actuator extends under a predetermined command pressure, and
• wherein each actuator comprises a bladder in a general form of a toroidal segment of flexible material encased in a spiral spring.