The Minuteman II was created to improve on the missile guidance systems, payload capacity, and anti-missile defenses of the Minuteman I. The first test launch of Minuteman II occurred at Cape Canaveral in 1964 and the first operational launch occurred one year later.
More Accurate, More Powerful, More Deadly
The second generation of the Minuteman missile, Minuteman II, differed from its predecessor in several important ways. It was a larger missile designed to accommodate increased engine and warhead size, measuring 57.6 feet long and weighing seventy thousand pounds. As with its predecessor, Minuteman II was capable of reaching speeds in excess of fifteen thousand miles per hour.
Minuteman II offered an improved second-stage engine manufactured by Aerojet-General, improved targeting system, extended range, electronic autopilot, all-inertial guidance system, and a 1.2 megaton nuclear warhead. These improvements allowed the Minuteman II to strike targets from a greater distance with greater precision. New anti-missile technology increased the chances of the missile avoiding an enemy's defenses and delivering its warhead.
Conversion & Installation - Moving from Minuteman I to Minuteman II
As part of the Force Modernization Program begun in the mid-1960's to modernize the Air Force missiles, the Minuteman II ICBMs would eventually replace the entire fleet of Minuteman I ICBMs. The first operational Minuteman II squadron went on alert at Grand Forks Air Force Base in North Dakota during 1966. Minuteman II ICBMs eventually went in the ground at another five bases.
These bases were Malmstrom Air Force Base in Montana, Ellsworth Air Force Base in South Dakota, Minot Air Force Base in North Dakota, F.E. Warren Air Force Base in Wyoming and Whiteman Air Force Base in Missouri. Malmstrom Air Force Base was also selected as the location for an additional Minuteman squadron, and Launch Facilities and Launch Control Facilities were consequently constructed at this base.
The Presence of the Past
The two sites which make up Minuteman Missile National Historic Site – Launch Control Facility Delta-01 & Launch Facility (Missile Silo) Delta-09 - are associated with the Minuteman II system and its configuration. These sites were protected for historic purposes by the Strategic Arms Reduction Treaty (START).