Air Force history of ICBM development, safeguarding America

Published March 5, 2012
By Senior Airman Reggie Manning
341st Missile Wing Public Affairs

MALMSTROM AIR FORCE BASE, Mont. -- During the latter months of 1957, some Americans could stand on their back porch and catch a glimpse of the Soviet Union's satellite, Sputnik, orbiting across the sky. To many, this slight sparkle was viewed as simply an advancement in technology, but to the United States government, it was much more. The launch of Sputnik was a dreadful eye opener that the U.S. was at the tail end of the arms race.

The military, as well as the CIA, knew that Sputnik wasn't just a test satellite and that it was a taunting flag out of the barrel of a gun masking the Soviet Union's true plans, which were to develop a long-range ballistic missile.

America's military ICBM program had all eyes on its progress when Congress demanded answers about the current status of national security. In light of the Soviet Union's progress, the program finally received the attention and funding it desperately needed to make progress.

Atlas ICBM
In January, 1951, the Air Force directed Convair Corporations to do a $500,000 study project on the development of an ICBM capable of delivering an atomic bomb; this undertaking was known as 'Project Atlas.'

Weighing 267,000 pounds and standing 82 feet tall, the Atlas ICBM had a range of 6,400 to 9,400 miles, and could be armed with a 1-megaton thermonuclear warhead. The Atlas was equipped with a "stage-and-a-half" propulsion system, which meant it was powered by two large booster engines and a smaller sustainer engine that worked together. This new ICBM technology was accurate within one and a half miles.

There were a total of six different Atlas designs, the A, B, C, D, E and F-Models. The first three were meant solely for prototyping purposes and were never deployed.

The majority of the Atlas ICBMs were stored vertically in above-ground launchers that provided blast protection against overpressures of only five pounds-per-square-inch. The Atlas F-model was the first of the ICBM family to be stored vertically in underground silos, protected by heavily reinforced concrete that could withstand overpressures of up to 100 psi.

Due to the Atlas being fueled by liquid oxygen and kerosene, the silos were extremely dangerous and difficult to maintain.

After the deployment of the new solid-fueled Minuteman ICBM in early 1963, the Atlas became rapidly obsolete.

Upon retirement from operational ICBM service in 1965, the Atlas went on to become refurbished and served as space launch vehicles for nearly 20 years.

Titan ICBM
During the summer of 1954, the Air Force acknowledged the obvious limitations of the Atlas ICBM and began rapid studies on a new weapon system to serve as a back-up in case the Atlas failed. In October, 1955, the Air Force awarded the Titan I contract to the Glenn L. Martin Aircraft Company of Baltimore.

The Titan I was America's first multi-stage ICBM. Unlike the Atlas' stage and a half, the Titan housed a two-stage propulsion system. Once the first and second stages were exhausted, the engines and fuel tanks for that section dropped off respectively, decreasing the weight of the missile.

The first Titan I squadron was activated in April, 1960, at Lowry AFB, Colo.

Standing at 98 feet tall, the Titan I had a range of 6,350 miles and could carry a payload of 3,825 pounds- more than twice the capacity of the Atlas.

Another difference between the Titan and its predecessor was its hardened underground silos. The only downfall was the fact it could not be launched from within the silos and once fueled, had to be raised before being launched.

The Titan II had twice the payload as the original version and featured a storable fueling system. The new modifications gave the Titan II the capability of being fired from its underground silo, though the fuel was highly toxic and experienced many leaks that made the weapon difficult to handle.

Minuteman ICBM
The early ICBMs, such as the Atlas and the Titan, had one major flaw that rendered them dangerous to operate, expensive to maintain and difficult to deploy, and that was liquid fuel. After a briefing by Col. Edward Hall on the benefits and feasibility of a solid-fueled ICBM, the Air Force Ballistic Missile Division began immediate research and development on a new weapon called the Minuteman. The contract to assemble and test this weapon was awarded to Boeing Airplane Company in September, 1959.

Malmstrom was the only base to house the Minuteman 1A and received the first one on July 23, 1962.

As the smallest ICBM ever deployed, the Minuteman 1A was initially designed to be a mobile weapon which limited its range and firepower compared to other models. On Feb. 12, 1969, Malmstrom removed the last Minuteman 1A from its silo and immediately began replacing them with the Minuteman 1B.

The Minuteman 1B was developed to improve the capability of the Minuteman without increasing its actual size. The 1B model also utilized a new reentry vehicle and new second stage motor casing, which effectively increased both range and firepower. Also, a new guidance system was installed enabling the weapon to store two sets of target coordinates. In case the missile could not reach its primary target it could retarget on the secondary; this improvement was called "Engaging a target of opportunity."

With the cancellation of the mobile launching system, the Minuteman 1B now had room for improvement within its size. On Oct. 2, 1963, the Air Force began the process of developing the Minuteman II program.

The Minuteman II was not only an upgrade in size from the Minuteman I models, but it introduced a new guidance system and had the capacity of storing up to eight sets of target coordinates. This new system would also be resistant to a nuclear blast.

The first tested silo launch of the Minuteman II was achieved on Aug. 18, 1965.

Since the weapon featured new technology such as the micro-circuitry guidance system, the missile suffered from significant reliability problems.

On July 15, 1965, Boeing Aerospace received a contract to begin the research and development of a new ICBM titled the Minuteman III. The new weapon was basically a Minuteman II with a redesigned and improved guidance system, upgraded third stage and superior warhead section. Since this model resembled its predecessor, it could be stored in Minuteman II silos avoiding the cost of reconstruction.

In 1965, NASA launched a refurbished Titan missile into space, which deployed four different satellites into individual orbits. This idea influenced the Minuteman III, which introduced the MIRV system (Multiple Independently- Targeted Reentry Vehicle). The Minuteman III could focus on three different targets and deliver a warhead to each within one launch.

These advances in nuclear warfare lead to the development of the Peacekeeper ICBM, which was capable of carrying 10 independent warheads and was designed to replace the Minuteman series. After the signing of the START II agreement (Strategic Arms Reduction Treaty,) where the United States and Russia agreed to dismantle and stop to the production of ICBMs that had MIRV capability, the Minuteman III, as well as the Peacekeeper, reduced its payload to single warhead weapons.

Through the history of ICBMs, the Air Force has always focused on ways to improve their weapon systems. From the Atlas ICBM that was stored outside and took hours to launch, to the Minuteman which could be launched in a minutes' notice from an unmanned silo, the research in ICBM technology improved with each model. The Air Force vigorously researched innovative ways to ensure that America had the most powerful, safest and expeditious nuclear missiles in the world.

Content in this article was taken from the following books: "Nuclear Weapons of the United States," by James N. Gibson, and "To Defend and Deter," by John C. Lonnquest and David F. Winkler.