An assembly includes a structure with 6 o'clock and 12 o'clock beams and front and rear curved beams, in which the 12 o'clock beam is mounted to be able to rotate on a pylon of an aircraft between a closed position and a raised position, a fan cowl fixed to the structure, a thrust reverser with a rear cowl and that is able to move in translation along the 6 o'clock and 12 o'clock beams between a forward position and a backward position, cascades fixed to the thrust reverser, and a mover for moving the thrust reverser. With such an arrangement, the fan cowl and the thrust reverser are fixed to the same structure, and it is this structure that is hinged to the pylon.