A payload control device

A method of controlling a position of a suspended payload coupler, the method comprising:

• providing a payload coupler suspended from a lower end of a line which is coupled at its upper end to a lifting device, the payload coupler having a propulsor configured to generate a resultant propulsion force having at least a component perpendicular to the axis of the line when the line is hanging taut under gravity,
• operating the propulsor to generate a propulsive force to maintain the payload coupler in a first stable position or to move the payload coupler along a predetermined path;
• and
• coupling a payload to the payload coupler or decoupling a payload from the payload coupler while the payload coupler is maintained in the first stable position or moved along the predetermined path.