OPERATION HARDTACK I -
DATE:
TIME:
PPG Time
11 June 1956
0530
Maple
GMT
Sponsor:
10 June 1958
1730
SITE:
UCRL
PPG - Bikini - South of
Fox
17° kit
165° 2kt
ws"
su"
Site elevation:
HEIGHT OF BURST:
N
E
Sea
level
11.58 ft
TYPE OF BURST AND PLACEMENT:
Surface burst from barge on
water
CLOUD TOP HEIGHT: 40,000 ft MSL
CLOUD BOTTOM HEIGHT: 1M
REMARKS:
Only individual island dose rates are available.
These were obtained
from Radiological Safety organization helicopter surveys at H+4 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 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 t7°®
decay approximation was used to extrapolate the H+4 hour dose-rate
readings to H+tl hour.
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