zadar-equipped search aircraft.

Second, since initial BRAVO data were

available, the method used to determine the air radex volume, or area, was
cnanged for high-yield bursts.

The new method considered the initial ra-

jiation source aS an area ratner than a point.

On the morning of 26 March, a favorable forecast of H-hour winds for
the following day set in motion once again the entire preshot schedule of
events.

This forecast gave east-northeast winds to approximately 8,000

Feet (2.4 km), southerlies to about 12,000 feet (3.7 km), southeasterlies
zo 20,000 feet (6.1 km), southerlies to southwesterlies to about 55,000
feet (16.8 km), and east-southeasterlies to easterlies above 55,000 feet
(16.8 km).

All units and external agencies were notified accordingly that

che ROMEO schedule was firm for 27 March at 0630.
Following the noon command briefings, CINCPAC was advised of the forecast 72-hour air particle trajectories for 10,000, 30,000, 40,000, and
50,000 feet (3.05, 9.15, 12.19, and 15.25 km).

The advisory stated that

no significant fallout was forecast for populated Marshall] atolls and recommended no closure of air routes.

[It also stated that no fallout problems

were forecast outside Area Green and that an intensive search was being

conducted in this area, plus a 240-nmi (445~-km) wide sector out to 600 nmi
(1,110 km), centered on a true bearing of 340°.

(The sector search was

scheduled and run again postshot centered on 305° true from 200 nmi [370

kmj to 600 nmi [1,110 km] from ground zero.

Starting at H-2, four search

aircraft were used on Parallel flight tracks, with 60 nmi [111 km] coverage per aircraft, in advance of the cloud.)

In addition, CINCPAC was re-

quested to divert all shipping from the sector covering 260° clockwise to
90° true out to 450 nmi

(833 km)

from ground zero.

a statement that no known shipping was in this area.

The request included
Table 28 shows the

known transient shipping near the Pacific Proving Ground

(PPG) on shot day.

At approximately 1500 the surface and air radex areas were announced
as follows:

251

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