OPERATION HARDTACK IPPG Time
13 May 1955
0630
TOTAL YIELD:
Time to Ond maximum:
Radius at 2nd maximum:
Diameter:
Depth:
Lip:
SITE:
LASL
PPG - Eniwetok - West
end of Gene
12° 4o't
30"
N
1620 12'
20"
8
Site elevation:
Sea level
1.37 Mt
FIREBALL DATA:
Time to lst minimum:
CRATER DATA:
Sponsor:
GMT
12 May 1958
1830
100 msec
0.94 to 1.35 sec
3,641 ft
4,000 ft
171 ft
HEIGHT OF BURST:
3 ft
TYPE OF BURST AND PLACEMENT:
Surface burst from 10 ft deep
tank of water sitting on coral
soil
CLOUD TOP HEIGHT:
T2,eCO ft MSL
CLOUD BOTTOM HEIGHT:
NM
Apparently washed away
REMARKS:
Only individual island dose rates are available.
These were cbtained
from Radiological Safety organization helicopter surveys at H+ hours.
The heliccpter survey technique called for the pilot either to land
une aircraft at the desired spot, so that a sround 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 t-1-2
decay approximation was used to extrapolate the H+4 hour dose rate
readings to H+l1 hour.
201
—
DATE:
TIME:
Koa