26a. Constraints from R_head vs. R_bullet—SL6A—m_head = 5 lb

    The pages of this section follow a different order from the previous section because they have v_cloud instead of PE. Each begins with the major constraining variable, v_frags, and then moves to the secondary constrainer, t_lurch. After that, it presents the three constrained variables v_lurch, v_cloud, and v_snap in that order. The constraints on v_frags and t_lurch are as described in the previous section. 

For m_head = 5 lb

v_frags, ft s^-1

    As before, values of v_frags are disallowed if they are <0 or >1100 ft s^-1. In this case, all the values were allowed, and ranged from 180 to 550 ft s^-1. The mask of disallowed values shown in boldface comes from t_lurch (next table), and restricts the allowed values to 240 to 550 ft s^-1.

t_lurch, ms

    As before, values of t_lurch were allowed only if they were >0 or <25 ms. The resulting pattern of constraints is shown in the table below. It formed a diagonal pattern though the middle of the table. Acceptable values ranged from 11 to 24 ms.

v_bodyafter, ft s^-1

    The speed of the rearward lurch ranged from 1.35 to 1.40 ft s^-1, a practically negligible range. When masked by the constraints of t_lurch, the remaining acceptable speeds, all rearward, were 1.35–1.39 ft s^-1, which did not include the observed -0.8 ft s^-1. This appears to suggest that the mass of the head cannot be 5 lb, but may mean instead that the default PE of 300 ft-lb used for these calculations is in error. When the values of 510–570 ft-lb found for a 5-lb head and SL7A are used, much more realistic lurches are found. All in all, though, 5 lb seems to be too light.

v_cloud, ft s^-1

    The velocity of the cloud, whose range is here explored for the first time, varies only mildly, from 370 to 420 ft s^-1. The allowed values are the same because the disallowed values are all between 415 and 420 ft s^-1.

v_snap, ft s^-1

    The velocity of the forward snap ranges from 4.4 to 9.9 ft s^-1 overall. The constraints from t_lurch reduce the range to 4.4 to 6.7 ft s^-1. This range is consistent with the observed v_snap > 3.3 ft s^-1.

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