LINDEN
OPERATION HARDTACK
1.
LINDEN was detonated at 1500M, 18 June 1958, on a barge located
one mile west of Yvonne Island, ee
the cloud to rise to 20,000 feet, then to stabilize at 19,000 feet.
The
weather radar on Fred and the cloud sumpling aircraft were both used to
follow the cloud movement.
2.
The main body of the elcud moved northwesterly, passing over
Mask and the northwestern islands from Aliee to Janet.
Net movement was
only seven knots in speed, with the result that the lagoon was not cleared
until Ht+at, when Re-entry Hour was declared.
The P2V was used to follow
the south edge of the cloud as it moved off.
The plane was then vectored
for a final sweep of the northern half of the atoll just before Re-sntry
Hour, and the only significant rsadingsa obtained were near ground zaro.
3,
darkness,
The initial helicopter survey was cut short due to approaching
A detailed survay was made at 081 5M the next morning, ond signi~
ficant readings were obtained only at the islands mentioned above.
They
ranged from 10 r at Mack to 24 mr at Janet.
4.
The predicted fallout plot was in a very narrow area along an axia
of 280 degrees from ground zero,
The actual area was senewhat wider ard
fell between the radials 270 degrees and 320 degrees, for a distancs of
approximately forty miles.
All significant fallout fell within the published
hazard area.
°
BEST COP
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Aoofcer
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TAB A
222