The 'WNCH' cable may be thought of as attached to a winch providing constant tension in that mooring line. This type of cable can be attached between a structure and a fixed point or attached between two structures. This model of a cable therefore represents a force of constant magnitude but with varying direction.

The magnitude of this force is given by the value of parameter (6) input in columns 31-40 and is constant throughout the analysis.

(A) For a cable attached between a structure and a fixed point:

The direction of this force is given by the vector going from the position of the attachment node (3), at any stage in the analysis, to that of the fixed node (5) as defined in Data Category 1 in the Fixed Reference Axis system (FRA).

(B) For a cable attached to two structures:

The direction of the force on one structure, at any stage of the analysis, is given by the vector from the position of the attachment node (3) on that structure, to the position of the attachment node (5) on the other structure. The forces on each structure will therefore always be equal and opposite. Note that the interchange of parameters (2) and (3) with (4) and (5) has no effect.