CHAPTER V OPERATION CASTLE 3.LL THERCN. CLEAR Operation CASTLE was to contain about seven, ill~thermemiclear detonations and begin about 1 September 1953, some 11 months following Operation IVY, Colonel Howell M. Estes, Jr., 12th Air Division of the Strategic Air Command, was to command the Air Task Group and, on 1 November 1952, he visited the Pacific Proving Grounds to observe the MIKE Shot.” In February 1953, Task Force 132, which coriducted Operation IVY reformed into Joint Task Force SEVEN for Operation CASTIE and, shortly after became a permanent organization for future overseas test series.- Instrumentation and tuilding at the Pacific Proving Grounds could not be started before the results of the UPSHOT/KNOTHOLE were known though mich was prepared by November 1953, Since this was typhoon season in the Pacific, CASTLE tests were rescheduled for the spring of 1954. Air Force headquarters announced Operation CASTLE would begin at the Pacific Proving Grounds as ‘soon as conditions permitted, General Mills organised the office of deputy coumander for overseas tests and assigned the duty to Colonel Edward M. Gavin. Colonel Gavin worked closely with the Center staff for the interim between IVY and CASTIE, One of his major projects was to consider various airplanes which might meet new sampling requirenents .7 . | *on 29 November 1952, Colonel Estes became Brigadier General, his new rank paralleled planning for Operation CASTIE, 93 SWEH-2-003)