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 checked, and rechecked. Then on 19 July, JTF 1 conducted a fullscale dress rehearsal, dubbed "William Day." All units of the task force participated fully except the air task units. Heavy cloud cover and rain limited aircraft participation in the rehearsal (Reference C.9.206, Part VII, p. E180).

On D-1 (24 July) CJTF 1 confirmed BAKER Day as 25 July and designated shot time for 0835. Weather forecasts indicated that there would be favorable weather on that day. Evacuation of task force ships and personnel began immediately. Personnel and ships not needed immediately after the shot were evacuated to Rongelap Atoll instead of Kwajalein because it was closer to Bikini. USS Saint Croix (APA-231) evacuated 607 U.S. personnel and natives from Enewetak on 21 July.

The day before BAKER, two C-54s were again sent to Enewetak and Roi islands to transport the cloud samples to Kwajalein on 25 July. Five C-54s were again positioned at Enewetak in case evacuation of essential personnel was necessary. Except for minor changes, the aircraft missions were similar to the ABLE shot missions. Table 9 shows the aircraft that participated in BAKER, and Table 10 summarizes their orbit areas.

By 1735 on 24 July all but 13 support ships were clear of the lagoon. These cleared the lagoon by 0700 the following morning. Task force personnel on the islands at Bikini were evacuated by 1555 on 24 July. Three sailors on USS Gasconade (APA-85), a target ship, were somehow overlooked. They filled the yardarms with bunting (the signal that they needed evacuation) and were picked up by USS Conserver (ARS-39) at 0530 on 25 July (Reference C.9.206, Part VII, pp. H5-H7).

The bomb was suspended 90 feet (27.4 meters) beneath the surface of the lagoon from medium landing ship LSM-60. The LSM had been extensively modified to provide rigging facilities, a laboratory, and special radio receivers and transmitters. The bomb was encased in a strong, watertight, steel caisson and had a coaxial cable running from it to the LSM. The TG 1.1 laboratory personnel associated with the bomb arming were evacuated from LSM-60 at 0545 on 25 July (Reference C.9.206, p. 5-12).

There were 68 target vessels in the array for Test BAKER. Twenty-four small craft were beached on Bikini Island. Their positions are shown in Figure 28. The submarine USS Searaven (SS-196), which had been submerged on 24 July, partially surfaced later in the day. It was finally resubmerged by 2300 on 24 July. Of the eight target submarines, six were submerged and two were on the surface for the test (Reference C.9.206, Part VII, p. F10).

Weather was not quite as important for BAKER as for ABLE because the underwater detonation was expected to limit the cloud height and thus localize the radioactivity. Good visibility, however, was important for photography (Reference C.9.206, Part IV, p. C7).

BAKER TEST

BAKER was detonated on schedule at 0835 on 25 July 1946. The detonation command was sent by radio using coded signals. The weapon yield was 23 KT.

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