speed in approximately 19 years. The coil parameters =1011 (A/m2), = 5 mm, =6,500 (kg/m3), resulted in an estimated coil mass is =1,232 tonnes. Although the critical current density was based upon a 2000 Zubrin NIAC report projecting values through 2020, the assumed value is close to that for commercially produced YBCO coated superconductor wire in 2020. The mass estimate may be optimistic since it assumed that the entire coil carrying mass is superconducting while 2020 manufacturing techniques place a thin film on a non-superconducting substrate. For the interstellar medium plasma density =1.67x10−22 with an apparent wind velocity 5% of light speed, the ion gyroradius is 570 km and thus the design value for meets the MHD applicability test of equation . Equation gives the required coil current as ~7,800 kA and from equation = 338 tonnes; however, but the corresponding superconducting wire minimum radius from equation is =1 mm, which would be insufficient to handle the decelerating thrust force of ~ 100,000 N predicted by equation and hence the design specified = 5 mm to meet structural requirements. In a complete design, the mass of shielding the coil to maintain critical temperature and survive abrasion in outer space and other infrastructure must also be included. Appendix A estimates these as 90 tonnes for wire shielding and 50 tonnes for the spools and other magsail infrastructure. Freeland compared this magsail deceleration design with one where both acceleration and deceleration were performed by a fusion engine and reported that the mass of such a "dirty Icarus" design was over twice that with the magsail used for deceleration. An Icarus design published in 2020 used a Z-pinch fusion drive in an approach called Firefly that dramatically reduced mass of the fusion drive and made fusion only drive performance comparable to the fusion and magsail design. In 2017 Gros reported numerical examples for the Magsail kinematic model that used different parameters and coil mass models than those used by Freeland. For a high speed mission to Alpha Centauri with initial velocity before deceleration using a coil mass of 1500 tons and a coil radius of =1600 km. The estimated stopping distance was of 0.37 (ly) and a total travel time of 58 years with 1/3 being deceleration. In 2017 Crowl documented a design for a mission starting near the Sun and destined for Planet nine approximately 1,000 AU distant that employed the Magsail