Withthehelp of three FSi airoraft from the first flight, another hazy hole was later located and these aircraft were directed to sample in a random manner in likely clouds in its vicinity. They were able to find only very diffuse, low-intensity material and were unable to collect very large samples. The middle flight of aircraft experienced a mimber of mechanical and limited-fuel aborts so that no samples were collected between H43 ard H+5 hours. During this period, however, the director aircraft received a series of Eniwetok wind observations and was able to predict with reliability the position of a section of the cloud lying between 36,000 and 13,000 feet. It, therefore, descended to spproximately 38,000 feet, crossed below a heavy portion of higher cloud which lay along the line of flight of ths predicted layer, and found a hazy hole on oms side of which a bank of heavy white clouds could be seen. Since these clouds gava evidence of gamma radiation when approached by the director aircraft, the last flight of F840 aircraft wera brought from sero point to this position, one pair flying a systematic search mission enroute, the second pair being brought directly to the director amd vectored into the target clouds. Both pairs of P&G aircraft were siccessful in finding diffuse cloud material of low concentration, Had their flight tine been Icnger or this position achieved earlier, it is possible that the samples Collected by them might have been larger. The presence of high altituce cirrus, as well as a marked velocity and directional wind shear between 50,000 and 60,000 feet, also adversely