bile 10 March 1954 - MEWORANDUM FOR RECORD SUBJECT: 1. Protection of Transient Shipring During Operation CASTIZ In order to provide protection for transient shipping in the region immediately outside the Eniwetok/Bikini Danger drea during Operation CASTLE factors were established and a plan of action placed in effect as follows: a. Plaming fectars: (1) CASTLE clouds nore than 24 hours old should not be hasardous. | (2) De Plan: (1) The Comander in Chief, Pacific Fleet was requested to ake advance diversions of shipping catside a sector area from southwest clockwise through north to east to 500 nantical miles from ground sero fros H to H plus 24 hours. 7 Aa 24 hour travel of a CASTLE cloud should be apprezimately 500 nautical miles. (2) P2Vv aircraft were planned to sweep the significaxt forecast sector of cloud travel, using visual ani search radar methods of sightings cut to 800 narc- tical miles on De2 days, out to 600 nautical niles on Del day and, if necessary, in front of the cload on D day. P2V aircraft crews were directed to eto fect diversion on all ships sighted in the sector area on Dei end D day. (3) WB-29 aircraft on rcutine weather reconnaissance missions were directed to report all sightings of surface shipping encountered, Ala sightings were to be relayed to the Rader center (CIC USS BATROED) =~ in the TG 7.3 fleet. (4) P2v aircraft and destroyer security sweeps were di- rected for the Eniwetck/Bikini Danger Area. Inform mation fron these sweeps was channeled to the Radar center (CIC USS BAIROKD). mar -