The present invention relates to a torque sensor, in particular to a torque sensor for the detection of the torque in the shaft train of a drive system, in particular of a high lift system in an aircraft comprising a torsion spring having first and second sides which are rotated with respect to one another by a torque applied to the torque sensor.  Such a torque sensor is, for example, integrated into the drivetrain of a drive system in that the first and second sides can be connected and/or are connected to corresponding drive shafts of the drivetrain. 
Previous torque sensors measure the torque using strain gages or piezostrictive sensors or magnetostrictive sensors are used.  These sensors are, however, not robust enough for use over many years, in particular in aeronautics.