Pd

ASPEN EVENT
OPERATION HARDRACK

1,

The ASPEN device was detonated on a barge 3,000 feet southwest of

Charlie Island, Bikini Atoll, at 0530M, 15 Jyns 19058,

Radar establishad

the cloud height at 48,600 feet; aircraft estinated the top at 55,C00 feet.
Within thirty minutes the cloud had moved well to the northwest of the lagoon.

2,

A P2V airoraft (Wiidroot 11) reported over Nan at H+30 minutes, and

it was vectored scross the eastern asction of the lagoon.

readings were recorded.

Only background

At 0645M, the P2V had searched the entire l:goon,

and the highest reading was made two miles sast of ground gsro:

5.5 ar/br.

Re-entry hour was declared at O7COMe

3,

Tyo helicopters took off from Nan at 0730M, and negative readings

were reported at William and How,

A second detailed survay was conducted

at H+7 hours,
4,

Fallout was predicted along a true bearing of 300 degrees for 4

distance of 200 miles.

It is estimated that all fallout fell within this

area ,

5,

Excellent communications with the USS Benner contributed to the

succass of this event.

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my act

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