Nishida 2005 results reported a coefficient of drag that increased non-linearly with attack angle from a minimum of 3.6 at =0 to a maximum of 5 at =90 degrees. The steering angle of the thrust vector is substantially less than the attack angle deviation from 45 degrees due to the interaction of the magnetic field with the solar wind. Torque increases from = 0 degrees from zero at to a maximum at =45 degrees and then decreases to zero at =90 degrees. A number of magnetic sail design and other papers cite these results. In 2012 Kajimura reported simulation results that covered two cases where MHD applicability occurs with =1.125 and where a kinematic model is applicable =0.125 to compute a coefficient of drag and steering angle. As shown in Figure 4 of that paper when MHD applicability occurs the results are similar in form to Nishida 2005 where the largest occurs with the coil in an axial orientation. However, when the kinematic model applies, the largest occurs with the coil in an radial orientation. The steering angle is positive when MHD is applicable and negative when a kinematic model applies. The 2012 Nishida and Funaki published simulation results for a coefficient of drag , coefficient of lift and a coefficient of moment for a coil radius of =100 km and magnetopause radius =500 km at 1 AU. These results included the effect of the interplanetary magnetic field (IMF, which can significantly increase the thrust of a magnetic sail at 1 AU). Magnetic field model In a design, either the magnetic field source strength or the magnetopause radius the characteristic length must be chosen. A good approximation for a magnetic field falloff rate for a distance from the field source to magnetopause starts with the equation: where is the magnetic field at a radius near the field source that falls off near the source as as follows: where is a constant multiplying the magnetic moment (A m2) to make match a target value at . When far from the field source, a magnetic dipole is a good approximation and choosing the above value of with =2 near the field source was used by Andrews and Zubrin. The Amperian loop model for the magnetic moment is , where (A) is the current and is the surface area (m2) for a coil (loop) of radius (m). Assuming that and substituting the expression