piiibditiebbidimee,- (7 lO March 1954 MEMORANDUM FOR RECORD SUBJECT: Protection of Transient Shipping During Operation CASTIE 1. In order to provide protection for transient shipping ia the regica imediately catside the Eniwetok/Bikini Danger Adres during Operation CaSTLE factars were established and a plan of action placed in effect as follows: Planning factors: (1) CASTLE clonds mare than 24 hours old sbould not be hasardous. (2) MG mately 500 nantical miles. Plan: (1) The Comasnder in Chief, Pacifie Fleet was requested to make advance diversions of shipping outside a sectar area from southwest clockwise through sorth to east to 500 nantical miles from ground sere froa H to H pins 24 hours. (2) P2V aircraft were planned to sweep the significant forecast sector of aloud travel, using visual and search redar methods of sightings cat to 800 nantical miles on D-2 days, cat to 600 nautical ailes ~ dv. 24 hour travel of a CASTLE cloud should be apprexi- on De] day and, if necessary, in front of the cloud on D day. P2V aircraft crews were directed to ef> fect diversion on all ships sighted in the sector area on Dei ami D day. (3) WB-29 aircraft on rcutine weather reconnaissance missions ware directed to report all sightings of surface shipping encountered. Ald sightings were to be relayed to the Radar center (CIC USS BAT=0zD) “7 in the TG 7.3 fleet. (4) P2¥ aircraft and destroyer security sweeps vere directed for the Eniwetok/Bikini Danger area. Infar~ mation froz these sveeps was channeled to the Hadar center (CIC USS BAIROKD). mart