A winch assembly, comprising: a clutch (5; 105; 205), the clutch (5; 105; 205) comprising: an input shaft (110; 210) for connection to a drive means and being operatively connected to at least one input friction plate (120; 220) for rotation therewith; an output shaft (112; 212) for driving a winch and being operatively connected to at least one output friction plate (130; 230) for rotation therewith; a biasing member (128; 228) arranged to provide a biasing force that pushes the at least one input friction plate (120; 220) and the at least one output friction plate (130; 230) into contact with each other so that torque can be transferred from the input shaft (110; 210) to the output shaft (112; 212) via the input and output friction plates (120, 130; 220, 230); and a plunger (116; 216) disposed co-axially with and axially moveable relative to the output shaft (112; 212), wherein axial displacement of the plunger (116; 216) relative to the output shaft (112; 212) causes the biasing force to vary; a motor operatively connected to the input shaft (110; 210); a drum operatively connected to the output shaft (112; 212) for rotation about a drum axis; a cable attached to the drum and windable therearound to create a varying effective drum radius; and characterised by an arm having a first end operatively connected to the drum, such that its radial position, relative to the drum axis, changes as the effective drum radius varies, and a second end operatively connected to the plunger (116; 216). a clutch (5; 105; 205), the clutch (5; 105; 205) comprising: an input shaft (110; 210) for connection to a drive means and being operatively connected to at least one input friction plate (120; 220) for rotation therewith; an output shaft (112; 212) for driving a winch and being operatively connected to at least one output friction plate (130; 230) for rotation therewith; a biasing member (128; 228) arranged to provide a biasing force that pushes the at least one input friction plate (120; 220) and the at least one output friction plate (130; 230) into contact with each other so that torque can be transferred from the input shaft (110; 210) to the output shaft (112; 212) via the input and output friction plates (120, 130; 220, 230); and a plunger (116; 216) disposed co-axially with and axially moveable relative to the output shaft (112; 212), wherein axial displacement of the plunger (116; 216) relative to the output shaft (112; 212) causes the biasing force to vary; an input shaft (110; 210) for connection to a drive means and being operatively connected to at least one input friction plate (120; 220) for rotation therewith; an output shaft (112; 212) for driving a winch and being operatively connected to at least one output friction plate (130; 230) for rotation therewith; a biasing member (128; 228) arranged to provide a biasing force that pushes the at least one input friction plate (120; 220) and the at least one output friction plate (130; 230) into contact with each other so that torque can be transferred from the input shaft (110; 210) to the output shaft (112; 212) via the input and output friction plates (120, 130; 220, 230); and a plunger (116; 216) disposed co-axially with and axially moveable relative to the output shaft (112; 212), wherein axial displacement of the plunger (116; 216) relative to the output shaft (112; 212) causes the biasing force to vary; a motor operatively connected to the input shaft (110; 210); a drum operatively connected to the output shaft (112; 212) for rotation about a drum axis; a cable attached to the drum and windable therearound to create a varying effective drum radius; and characterised by an arm having a first end operatively connected to the drum, such that its radial position, relative to the drum axis, changes as the effective drum radius varies, and a second end operatively connected to the plunger (116; 216).