~ 35 inches
"The MK15 Mod1 went into production in September 1956. The MK15 Mod2 was a MK15 with a contact fuse. The initial military characteristics for the MK15 called for a true contact-bursting capability, that is, between zero and 30 feet. It was thought that a contact fuse might not operate close to the ground because of mass discontinuity, so an allowance was made for a near-contact burst. The MK15 used a proximity fuse for this, but by August 1954, LASL had analyzed data from the CASTLE shots and decided that contact with the ground could be tolerated in most configurations.
As a result of this conclusion, a feasibility study was undertaken to determine if a true contact burst could be achieved, either by the standard contact piezoelectric crystal method or by use of a new proximity fuse. This study was completed by April 1955. The MK15 Mod2 with a contact fuse was design-released by the end of February 1956, and training units were expected by the following September with the FPU (first production unit) in December 1956. In March 1957, the MK15 Mod2, using a new safing device and improved primary, entered the national stockpile. About 1,200 MK15s in several mods were produced between April 1955 and February 1957; all were retired between August 1961 and April 1965.
The MK15 was
11' 7" long, 34.7 inches in diameter, and weighed 7,600 lbs. The
bomb tail fins spanned 51 inches. The warhead could be fused for
either air or near-surface burst. The MK15 Mod0 did not have a drogue
parachute, but the Mod2 carried a small-diameter retarding