This new Stratofortress and its civilian counterpart, the 707, is the ultimate in modern jet aviation. Being built in Seattle & Renton, Washington, this sleek, flying beauty has eight turbojet engines, a wing span of 185 feet, weighs 175 tons, attains a speed of more than 650 miles per hour and a ceiling of more than 50,000 feet."
08/31/2012. The B-52/707 connection in the postcard caption is in the sense that the two newer aircraft were built in the same era and by the same company, as obviously the aircraft were not identical.
Further improvements to the RB-52B with gross weight increased to 450,000 lb (204,117 kg) and unrefueled range extended by the use of 3,000 gal (11,356 l) auxiliary fuel tanks to bring the total to 41,700 gal (157,852 l) or 271,000 lb (122,924 kg). The water injection system was changed to use two 150 gal (568 l) tanks in the leading edges of the wing roots.
This was the first B-52 model to use the white thermal reflecting paint on the under surfaces, although it was applied to B-52Bs already in service. On March 9, 1956, the pictured second B-52C was the first of 35 B-52Cs to fly:
10 B-52C-40-BO, serial 53-0399 to 52-0408, c/n 16878 to 16887
12 B-52C-45-BO, serial 54-2664 to 54-2675, c/n 17159 to 17170
13 B-52C-50-BO, serial 54-2676 to 54-2688, c/n 17171 to 17183