aircraft was at a 32,000-foot (9.8-km) altitude and a slant range of 91,000 feet (27.8 km). A Second B-50 IBDA aircraft was at a 30,000-foot altitude and a slant range of 182,000 feet aborted. (55.5 km). (9.1-km) The third JBDA B-50 A maximum radioactivity reading of 0.020 R/hr was record ed for 10 to 15 seconds onboard the B-36 effects aircraft; this was the 4d nly ra- diation noted by the effects aircraft during the CASTLE series. The Test The early cloud dimensions following the 0610 detonation are Figure 88. own in The lowest level of the stem (surface to 15,000 feet was influenced by 17.3-mi/hr (27.8-km/hr) winds from the east. .6 km]) Tris move- ment was confirmed by a cloud-tracking aircraft reporting a maxim inten- sity of 0.063 R/hr at H+4, 60 nmi (111 km) west-southwest of groun Jd zero at 10,000 feet (3.05 km). CONTAMINATION. Based on the position of cloud tracker contact and the forecast air trajectories, this contamination is believed to have passed The peak activity reported at En etak Remnants of this portion ,of the cloud probably a ount to the south of Enewetak Atoll. was 0.002 R/hr. for the 0.005 R/hr radiation level reported 460 nmi (852 km) ground zero during a weather reconnaissance mission on D+tl. sout The level of the cloud (16,000 to 60,000 feet [5 to 18 km]) moved to northeast at 17.3 mi/hr (27.8 km/hr). made with fallout from this segment. Several contacts were subs Between H+5 and H+7, the tr est of Liddle e eastuently ling edge of the cloud was clearly defined by one of the cloud-tracking air~ craft; maximum intensities of 2 R/hr were reported 300 nmi (556 k northeast of Bikini. east- The cloud top moved initially to the north a d west. In the fallout process, however, this debris was carried back towa d the east and intercepted several times. The first was at H+l5, when a tracker aircraft was able to completely delineate a fallout area that was entered 340 nmi (630 km) to the east-northeast of ground zero (92 nmi [170 km ] north of Bikar Atoll); R/hr. the maximum reading inside this area was a At the same time, another cloud-tracking aircraft located r activity of 6 R/hr in this same general area, but at an altitude of 304 ut 0.5 dio- 1,500