factor of 2 is assumed. The best current estimate of the actual yield is 11.0 + 0.2 Mt;* there- fore it appears that Mike shot had a slightly greater blast efficiency than the Tumbler-Snapper Te BO Bate AMATIMS RRhe RNB iheDhaai CALDEMS TE Caan! yt aiits average. Table $.6--REDUCED OVERPRESSURES AND SLANT RANGES, MIKE SHOT Canister No. AP/i, pei 2 3 4 8 ” 8 9 10 11 12 1.65 6.92 1.00 0.68 20.63 §.74 4.25 0.96 0.57 0.24 AR,ft 29,240 $1,970 107,010 162,510 15,670 30,080 $8,870 108,730 151,250 262,040 The “cot-mean-square percentage devis.tion of the observed peak overpressures from the computed curves is 20 per cent if the large deviation at canister No. i2 is included and 12.2 per cent if this point is omitted. it will be observed in Fig. 3.7 that there is quite satisfactory consistency between the reduced cata obtained from the parachute-gauge measurements and the overpressures measured on the ground for overpressures greater than about 1 psi. However, at the most distant ground point (114,240 ft), the ground-gauge value is decidedly low as compared to the air- borne-gauge value at an equivalent reduced range. It is very probable that this discrepancy at long ranges and low overpressures is due to upward refraction of the blast wave by the decrease of sound velocity with altitude. The reduced peak overpressures and slant ranges for King shot are given in Table 3.7 and ° STREETee the effective blast yield is the product of the actual yield and the ground reflection factor, the effective yield of 24 Mt corresponds to an actual yield of 12 Mt if the ideal ground-reflection are plotted (circled pointa) in Fig. 3.8. Since tle peak overpressures obtained at canisters Nos. 2, 3, and 5 are considered to represent the free-air peak overpressure in the direct wave * Table 3.7-—-REDUCED OVERPRESSURES AND SLANT RANGES, KING SHOT Canister No. AP/u, psi 2 3 5° 6 ” 9 10 i 2.24 1.19 1.10 0.224 0.822 0.788 0.740 0.651 AR, ft 17,680 29,790 $2,050 119,020 48,010 52,640 51,870 55,460 *Intormation from E. F. Cox as of 26 May 1953. 33 RESTRICTED DATA -(MM SECURITY INFORMATION Ry 33 ”