OPERATION HARDTACK I -
DATE:
TIME:
PPG Time
3 July 1958
0530
Cedar
GMT
Sponsor:
2 July 1958
1730
SITE:
UCRL
PPG - Bikini - SW of
Charlie, 4,000 ft from
the island
Site elevation:
HEIGHT OF BURST:
Sea level
10.8 ft
TYPE OF BURST AND PLACEMENT:
Surface burst from barge
on water
CLOUD TOP H=IGHT:
50,000 ft MSL
CLOUD BOTTOM HEIGHT:
35,000 ft MSL
REMARKS:
Only individual island dose rates are available.
These were obtained
from Radiological Safety organization helicopter surveys at Ht4 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 obtain a reasonable approximation of the true grouid 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 t-+°* decay
approximation was used to extrapolate the H+h hour dose-rate readings
to H+l hour.
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