different methods. The ratio of the maximum dvge rate on “hot spots,” {.c., small areas
of intense radiation, measured by film to that indicated by the T1B varied from 050 to
§. Mean values of 110 for impingement surfaces and 40 for sliding aurfacea were found.
The comparable variation in the ratio of average film dose rates to T1B doge rates was
from 300 to 3 with mean values of 55 and 26 for impingement and sliding surfaces, respectively.
It is also appare-nt from the tables that 2 wider variation exdats on ‘mpinge-
rom an examination of Tables 3.1 and 3.2, it can be coen that there {s considerable
variation from one shot to unother fn the general level of contamination picked up by the
TABLE 3.1
SUMMARY OF INSTRUMENT SURVEY AND FILM XEASURCMENTS ON F-84 AIRCRAFT
DURING PERIOD 2-4 HOURS AFTER DETONATION
Location of Film,
on F-84 Aircraf:
trie
Time of Penetration
loce
Tin of Penetretion
H+ 87 min; Uh + 6% min
Film rep/br
TiBrht Aveiia
H¢ 81 min; H + 88 min
Pile. vep/br
BFR eave Sdn
Side of Alr Intake
65
3,00
1,500
1,300
0.8
60
8
&
Side of Fuselage Belaw Compt.
6.7
5S
12
7
09
85
4
12
Wing Low Edge, Halfway Out
$4
3560
1,600
900
14
80
18
4
Side of Tip Tank
1.2
$0
x»
16
0o8
60
14
10
aircraft. A number of variables can be sggested that might account for this. Among
them are time and altitude of penetration, total tiuw ia cloud, type and y:etd of nuclear
device, type of burst, prevailing weatner conditions, condition of aircraft, and airspeed.
No doubt there ure others.
The data collected are mot sufficiently complete to cllow
inferences concerning the effects of these variables. all that can be said {ts that the
Burfaces of someof the aircraft became more heavily contaminated than others.
3.5
DEPTH DOSE STUDIES
Approximately fifty depth dose studies were made by ineans of stacks of photographic
film.
Two representative examples of the results are shown in Figures 3.3 and 3.4.
They show the dose experienced at various depths in stacks of lm exposed to the leadiag
edge of the wing at a point just inboard of the engine and to the tnboard side of the Up
tank. The dashed lines represent average values over the total area of the film, whereas
the solid lincs represent a aingle “hot spot,” or area of Intenge radiation.
The film stacks consisted of Eastman DF-19 and 0523 film. In the analysis ot the data,
the film nearest the surface was considered to have received 100 percent of the dose.
This {s justified for the purposes of this atudy, inasmuch as the 8.8-mg/cm’ wrapper
20
SECRET
Ee Ce rare
OTHER FACTORS AFFECTING THE NATURE OF
THE CONTAMINATION
> ee
3.4
Re en inte ta MSle eke we wae tes
E ee ett Ad mem, tam” ener ne
ete eb Oeste tematic tlt 2aI
of this study will be given in a later section. In almost all cases there is fair agreement
between these ratios and the film-to-T1B ratios.
conn a
ment surfaces than on sliding surfaces.
The values shown in the columns headed “Hot Spot @/y” and “Area #/y” are apparent
beta-gamia ratios as determined by depth dose studies with photographic film. Details