A fibrous tension member includes a plurality of structural threads and two or more indicator threads. The two or more indicator threads are located with respect to the plurality of structural threads such that a differential elongation between the two or more indicator threads indicates a curvature. The differential elongation between the two or more indicator threads is measured using a change in one or more electrical properties of each of the two or more indicator threads as each of the two or more indicator threads changes in length. A fibrous tension member includes a plurality of structural threads and one or more indicator threads. Each of the one or more indicator threads is more sensitive to elongation in a region of length of the fibrous tension member. The elongation of the region associated with one of the one or more indicator threads is measured using a change in one or more electrical properties of one of the one or more indicator threads as one of the one or more indicator threads changes in length.