se... The Raydist navigational system was used to determine the spatial positions of the B-47 and B-36 to an accuracy of plus or minus 150 feet on Shots 1, 2 and 6. Raydist was not available at Bikini on the fourth Data gained from Project 6.2b (B-47B) and 6.2a (B-36B) was to be shot. extrapolated for use in aircraft of similar configuration, such as the B-52. G. SAMPLING REQUIREMENTS Sampling requirements outlined by LASL called for six radio-chemical samples for each shot, including high altitude samples from above 50,000 feet. A sample consisted of a predetermined amount of radioactive mate- rial collected on seven to eight square feet of special filter paper. Twelve F-84's on each shot were expected to bring back half a sample each. The high altitude samplers were required to bring back one sample each. D. TECHNICAL PHOTOGRAPHY The third major phase of the Air Task Group's mi ssfon was technical photography. The purpose of the nuclear cloud Photography Program (Pro- ject 9.1) was the photogrammetric determination of the various parameters of nuclear clouds as a function of time and the attempt to establish approximate yield relationships. ‘The most important parameter was the rate of cloud rise and the areas of the cone swept out by the rising ma- terial. Of secondary importance was the dimension and drift of the cloud as functions of time after the cloud had reached its maximm altitude. This project required thrpe C-54!s, an RB-36 and a B-50. The RB-36 was equipped with gyro-stabilized mounts holding a K~17 aerial camera and ab WL ho 58