and angular accelerations; and elevator and wing deflections. Photography and temptape measurements of peak temperatures were also utilized. The principal resuits of the experiments are summarized in Table 6.2 and 6.3. The Shot 1 yield of about 15 Mt (approximately 25 percent in excess of the positioning yield) provided the highest peak overpressure, 0.81 psi, recorded on the B-36. The damage to the aircraft necessitated replacement of the bomb-bay doors, the aft lower Plexiglas blisters, and the radar-antenna radome. Superficial damage was encountered on the B-36 on Shots 2, 4, and 5. On Shot 5, the yield was predicted (12 Mt) with less conservatism compared to previous shot estimates; the fact that the actual yield was 13 Mt resulted in the largest temperature rise and stabilizer bending moment (for the B-36) obtained during the tests. The radiant exposure at the aircraft during Shot 5 was less than that for Shot 1, but the incident angle was smaller, resulting in more thermal energy being absorbed. This was apparent from the extent of the thermal damage cuf~ fered during Shot 5. The elevator skin was permanently buckled at four places, and a large perce itage of the paint on the stabilizer and elevator was blistered and peeled. A haze layer higher than 35,000 feet was reported by the B-47 crew on Shot 6. This layer provided a reflecting surface for irradiation and induced a noticeable amountof thermal irradiation on the upper surface of the aircraft. This was the only shot in which this crew noticed any significant heating of the crew compartment. Only on Shot 5 was cny nuclear radiation observed on board the aircraft. The maxi- mum value was 20 mr recorded in the B-36 crew compartment, with radiation detected over a period of about 20 seconds. After the return of the aircraft to the continental U. S., some residual radiation was detected that emanated from microscopic particles imbedded in the paint and lodged in the joints of the aircraft skin. The data obtained from the projects can be used to evaluate three related studies: (1) the correlation of inputs measured at the position of the aircraft with those inputs predicted by theory for such given parameters as yield, slant range, and altitude; (2) the verification of predicted effects of a nuclear detonation upon an aircraft; and (3) the prediction of the nuclear-delivery capabtlity of the aircraft involved. A postshot comparison between predicted and measured inputa and responses for the B-36 is tabulated in Table 6.4. The predicted figures were calculated using actual yield and aircraft range for each shot, therefore establishing a basis for evaluating the pre- diction methods, both for inputs and responses. A similar comparison is shown in Table 6.5 for the B-47 thermal! data. Thefirst tabulation of input data corrects the measured inputs to zero time i.e. to a point in space, in order to make a valid comparison with the calculated single-point values. Although compacisons are shown for values obtained with both radiometers and calorimeters, the calorimeter values are considered more reliable. Table 6.6 compares thermocouple and other temperature-indicating measurements to the predicted maximum temperature rise in panels having different thicknesses. Measured values were greater than calculated values in thin sking and smaller in thick skins. The attempt to evaluate the magnitude of temperature-induced strains in panels in- volved a complex stresa analysis and waa further complicated by the influence of tem-~ perature on the strain gages. For this reason, the data was not immediately available, but was considered in planning for Operation Redwing. The specific techniques used during Castle to predict thermal inputs and responses were inadequate for accurate, close positioning of the aircraft. Factors which contributed to the discrepancies were insufficient information on attenuation, absorptivity, and the cooling coefficient. As a result, it is apparent that a need still existed for continual 76