Single actuation system with redundancies and safety device, that is made up of a hollow roller screw [1]; a coaxial safety bar [2], located inside the hollow roller screw [1] and connected to this in the free edge of the same; a redundant nut [5] located in the assembly formed by the screw [1] and the safety bar [2]; a no-back device [6] located on one edge of the assembly screw [1] - safety bar [2]; a torque limiter [7], located on the bottom part of the no-back device [6]; at least two motors [8]; at least two position sensors [9]; a safety device [10] jointed solidaritily to the coaxial safety bar [2]; a main bearing system [3], jointed solidaritily to the screw [1]; a support [4] of the assembly, joint as well to the actuation system as to the element to be actuated.