Fig. 10 illustrates the spatial distribution of the upper rivulet when the cable vibration reduced to A=33.3 mm. Similar to the case of A=50.0 mm, the upper rivulet periodically oscillated on the cable surface. Fig. 11(a) and (b) shows the time history of the cable displacement and the averaged upper rivulet position, respectively. The cable steadily vibrated with 33.3 mm amplitude, and the averaged upper rivulet oscillated between 19° and 38°. The crest of the upper rivulet position was almost stable (around 37°), but the trough varied between 19° and 28°. This observation indicated that the upper rivulet oscillated more steadily at the position away from the cable top than as it moved close to the cable top. Fig. 11(c) shows the PSD of the averaged upper rivulet position and again the dominant frequency is 1.27 Hz. The upper rivulet oscillation and the cable vibration are compared in Fig. 11(d). The phase difference of the upper rivulet oscillation and the cable vibration was calculated as 0.24π(42.3°).