Chapter 3 RESULTS from Ll r/hr to 10 r/fhr. The aircraft had penetrated the c’o.d at an early time and were highly contamingted. The dotatied instrument survey and radicautographic studios re- quired three of the project personnel to remain fn the vicinity of the aircraft for 8 to 12 hours !mmediately after the aircraft landed. The radiation doses roceived under these circumstances were of the ceder of 0.5 to 1 r for the day. The total radiation dose after participation in seven ahota did not exceed the maximum permissible exposure of 3.9 r eatablisked for the opevation by the Commander of Joint Tay. Force Seven. The experi- ™mental plan and procedure proved to be sntisfactory. Considerable data which are directly applicable to operations in the field were colleciad. B.1 DISTRIBUTION OF CONTAMINATION The radioautographs obtained showed generally a uniform field of rad ation on which ‘were superimposed small areas of relatively more intense radiation. The uaiform field us the garsma iield that surrounded the aircrast. The number of inttuse regions varied from tesa than ten to several hundred per square centimeter. These areas of greatest intensity showed up on the film as dark spota renging in diameter from 0.1 mm to as much as ior 2mm. The radioautographs of the contamination showed po diff>rence be- tween Idletea-range and megaton-range shots nor between F-84 and B-57 aircruft. Figure 3.1 shows two typical radioautugraphs. The areas of contamination appear as darkened portions of the film. The contamination was most prominent {n crevices on the aircraft, In cracks, and around wivci heads or ofher irregularities in the surface. i r : a stare € pe he ene ee fe kere Ae coe The aircraft that were surveyed had surface gamma done rates at the same Iccation of In these cases che radioautograph was eurface area af-fhe aircraft. As might be expected, the leading edze of tha wing, nose, : or any other surface at which a sharp change in the cirection of the air flow occurred, f exhibited greater contamination than those surfaces where a smooth flow prevailed. These will be referred to as impingement and sliding surfaces, respectively. Examples of sliding surfaces are the top ami bottem surfaces of the wing and the wide of the fuselege. Figure 3.1 shows examples of the contamination pattern on both impingement and sliding surfanmag. Table 3.1 shows values for the intensities megzsured on F-84 aircraft contaminated by flights thrcugh the clouds from kiloton-range bursts. Table 3.2 shows simflar values for 8-57 aircraft contaminated by flights through clouds from multimegaton . Agtonations. The values shown are the average of a nunber of measurements made during the perted from 2 to 4 hours after detonation. da Appendixes A.1 and A.2. More complete tables can be found 32 INTERSTY OF RADIATION A wide range of dose rates was measured. The dose ratea varied from shot to shot 17 SECRET i : \ : I : 2 TRee ee Tee relatively sz.coth surfaces were chosen, since such surfaces predominate in the total a Tre a sharp outline of the object beneath the film with the crevices showing collections of relafively intense contamination. This in iitustrated by Figure 3.2, which ie the radioautograph of the canopy release button on an F-84. For the purposes of extensive study,

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