OPERATION HARDIACK I -
DATE:
TIME:
PPG Time
22 July 1958
1620
Juniper
GMT
22 duly 1958
0420
Sponsor:
SITE:
UCRL
PPG - Bikini - 4,000 ft
from west end cf Tare
11° 29'
165° 22'
L6"
15"
Site elevation:
HEIGHT OF BURST:
N
£E
Sea
level
12.11 ft
TYPE OF BURST AND PLACEMENT:
CLOUD TOP HEIGHT:
Surface burst from barge
40,000 ft MSL
CLOUD BOTTOM HRIGHT:
on water
24,000 ft MSL
REMARKS:
Only individual island dose rates are available.
These were obtained
from Radiological Safety organization helicopter surveys at H+ hours.
The helicopter survey technique called for the pilot either to land
the aircraft at the desired spot, so that a ground reading could be
obtained, or to make a slow pass over the desired spot at an elevation
of 25 feet.
Readings taken at 25 feet were multiplied by a factor of 2
in order to cbtain a reasonab.2 approximation ot the true ground
reading.
The basic instrument used in the aerial surveys was the AN/PDR-39
survey meter modified to read up to 500 r/hr.
The tl"? decay approximation was used to extrapolate the H+ hour dose-rate readings to H+1l
hour.
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