A second-generation liquid fueled intercontinental ballistic
missile, and the largest
ICBM ever developed by the United States. The concept originated in the late 1950's and construction of the launch complexes began in December of 1960. The first was turned over to the
Strategic Air Command March 31, 1963; there were 54 Titan II missile sites by the end of 1963. Of these, 18 were near
Tucson, Arizona (operated by the 390th Strategic Missile Wing of Davis-Monthan Air Force Base), 18 near
Jacksonville, Arkansas (308th Strategic Missile Wing of Little Rock AFB) and 18 near
Wichita, Kansas (381st Strategic Missile Wing of McConnell AFB). Each site took about 18 months to build and cost $8.3 million, not including the $2.2 million missile (1962 dollars).
The sites were designed to last 10 years, but served until President Ronald Reagan announced the Titan II phase-out in 1981 as part of SALT. For 22 years, the missiles were maintained in their hardened underground silos, kept loaded with propellants and pointed at enemy targets by highly trained combat crews.
The mission of the Titan II was deterrence. They were designed to destroy distant enemy targets in a minimum of time with high accuracy. The missiles could be launched within a minute of the crew's receipt of firing orders and could hit a target over 5500 miles away. These capabilities were never used, but served to fulfill the missile's mission, nevertheless.
Each missile (designation LGM-25c) was armed with a W-53 nuclear warhead which was probably 9 to 10 megatons, the specifics are classified. The warhead was placed inside a Mark VI reentry vehicle covered with a black ablative coating to protect it from the heat of falling through the upper atmosphere. Below the RV was the two-stage liquid-rocket-engine-powered vehicle comprised of the Stage I booster and the Stage II sustainer, each with its own fuel supply and engine. The Stage II section also contained the flight control and inertial guidance systems. Propulsion was provided by the combustion of nitrogen tetroxide (N2O4) and Aerozine 50 -- a 50/50 mix of hydrazine and unsymmetrical dimethylhydrazine ((CH3)2NNH2), abbreviated UDMH. Only the first 1/6 of a missile's flight time was powered; after the rocket stages detached, the RV would freefall to the target.
The Titan II missiles were 31 meters long, 3 meters in diameter and weighed almost 150,000 kilograms, fueled. They could cover 15000 km, fly nearly 12 km high and could reach speeds of 24,000 km/h. In the mid-1980's, 53 Titan missile sites were destroyed and the nuclear warheads dismantled and destroyed. The missiles were retrofitted and continue to be used to launch satellites. The only remaining intact site is in Sahuarita, Arizona, about 25 miles south of Tucson where it is operated as a museum.
If you are unable to visit in person, the following websites have more information and photographs:
http://www.teleport.com/~boelling/titanA.html
http://www.pimaair.org/titan_01.htm