KOA E
OPERATION
1,
A
The KOA device was a lend surface shot detonated at 0630M,
13 May 1958, at the west end of Gene Island, Entwetok Atoll. The
approximate yield was 1.25 MT.
Radar established the cloud height at
60,000 feet at 0637M, to the nortinest of Gene,
The main segment of the
cloud moved in a northerly direction and topped at 30,000 feet within thee
first hour.
2. The P2V aircraft (Wildroot 2) reported over Enivetok at OS00M,
and, using Yvonne as an axis, it was vectored along thirty-mile radials
commencing with 240 degrees and increasing by 10-degree increments.
tial runs recorded slight increases in background intensity.
Ini-
Maximm
intensity was recorded over Janet at 1010M, vith 460 mr/hr at 1,500 feet.
The entire legoon area was surveyed and the aircraft released at 1300M,
3.
ReHour was declared at 1000M, and the initial helicopter survey
was completed at 1030M.
on Alice,
Maximum ground reading was 40,000 mr/br recorded
Other north=-atoll islands ranged from 130 mr/hr on Sally to
14,000 mr/hr on Irene.
4.
Fallout forecast was genpeally accurate in extent and intensity.
Tha main axis of the cloud was forecast to extend northeast of Gene on a
hearing of 50 degrees.
5.
area,
vies
gis
It ts estimated that ali fallout dropped within the forecast
Within twenty-four hours background in this erea commenced to rise,
TAB A
St