 It was upgraded to the B-52D in 1968 by SAC along with receiving some older B-52Cs, which had limited use for training new aircrews.For several months in both 1968 and 1969, all of the 70th BW aircraft, most of the aircrew and maintenance personnel and some of its support people were loaned to other SAC units engaged in combat operations in the Far East and Southeast Asia.It was one of 11 SAC bomb wings that rotated such combat duty under the program known as Arc Light.