The fact that the impact φ₂ almost coincides with the take-off φ_O at Gamma~1.7 for N = 8 (shown by the trajectorygraph in Fig. 3b) allows a prediction for the breakdown of the periodic head-swinging (in Mode 1 or Mode 2) at much higher excitations: Keeping the chain unchanged, one would anticipate that increasing Gamma extends the flight time of the swinging head and postpone the landing φ₂, whereas take-off φ_O should occur at an earlier stage--- it is then unlikely that the head-swinging could be stably maintained if the main body already took off before the swinging head hit the substrate.