An auxiliary loading device (10) of a stretcher (20) on a loading plane (30), for example fixed or removable, comprising:a winch (11) which includes: a support frame (110) which rotatably supports a spool (111)；a tow strap (112) wound on the spool (111) and provided with a tow hook (113) that can be attached to the stretcher (20)； anda motor (114) connected to the spool (111) and configured to rotate the spool (111), in a first rotation direction for winding the tow strap (112) on the spool (111) and in an opposite second rotation direction for unwinding the tow strap (112) from the spool (111)；the auxiliary loading device (10) further comprising:a sensor unit (12) connected to the winch (11) and configured to detect a value of a parameter indicative of a tension of a section of the tow strap (112) comprising the tow hook (13) and unwound from the spool (111)； andan electronic control unit (100) operatively connected to the sensor unit (12) and to the motor (114) of the winch (11), wherein the electronic control unit (100) is configured to stop the rotation of the spool (111) when operated to rotate in the second direction of rotation if the value of the parameter indicative of the tension detected by the sensor unit (12) is less than or equal to a predetermined reference value thereof.
