tower shots,
According to Reference #10 there is a definite secondary
maximra fall-out area 50 miles NNE of the J-S crater, and the maximm
A Stokes’ Law
fall-out from J-U is 10 miles NWF of the ground zero.
analysis of the J-S secondary maximua indicates that according to the
vertical wind distribution pattern, this secondary fall-out came from
the upper pertion of the cloud. Since the fall-out from J-S and J-U
shots covered ene to two thousand square miles, and because only sight
to 10 square miles were examined during fall-out studies, it is the contention of this writer that such sampling was not representative.
There
is a great likelihoed that most of the fall-out downwind was not mea-
sured.
The Air Force Special Weapons Center also surveyed the J-S and
J-T7fall-out area on D and Del days using aircraft.
However, since all
the readings (except ground zero and three miles downwind) are made
from aircraft, it is not censidered reliable by itself.
Air readings
must be checked wth several ground readings before they could be can-
sidered reliable.
Also, it appears that as the yield of the bomb
decreases, the apparent percentage fall-out increases,
As a matter of
fact for U/K, shot Ray (100 ft tower, 0.3 ET bomb) the percentage fallout appeared to ba in excess of 40%,
This value was not entered in the
tables since it is not considerec reliable.
However, it does indicate
that when the actual fall-out is small (because the bexzb yield is small)
there is a tendency to overestimate the percentage fall-eut,
If the
bomb yield is large, a large area is contaminated and the intensity is
high and readily measurable.
Under such circuastances sanmplirg is
bhatt
adequate and the averaging process used in determining percentage fall-out
DOC 258
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