WALNUT EVENT
OPERATION HARDTACK
1,
The WALNUT device was detonated on a barge 5,000 feet southwest of
Janet Isiand, =niwetok Atoll, at 0630%, 15 June 1958.
Cloud height inforna-
tion and control of the Pov was ineffective during the first half hour
because of lack of cooperation from Eniwetok 40C,
Cloud height was estab--
lisked at 61,000 feet by aircraft report, at H+39 minutes.
Radar cloud
information was not available.
2.
The Pov atreraft (Wildrcot 2) was relsased by AOC to perform the
search at H+1 hour.
A quick ssarch of the lower lagoon area was made, ami
two tracks from Leroy (040 degrees and 350 degreas) were accomplished to
permit nose cone recovery operations to commence.
The highest reading
wa3 made over the reef three miles southwest of Alice:
2 r at 0755M.
The
cloud had moved rapidly to the ncrthwest and ra-santry hour was declared
at 830M.
3.
ta tree)
The helicopter survey commenced at 0905™.
Only background was
recorded with the exception of tke northwest chain, whieh ranged from
500 mr/hr to 30 mr/hr in the water near Edna.
4.
The P2V was vectored to the west for fifty niles, then placed in
an orbit east of Enivetok for two hours.
5.
.
It 1g estimated that all fallout fell within the predicted area.
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