Minuteman in Missouri, Part One

In June 1961, Whiteman Air Force Base, located 60 miles east of Kansas City and situated close to the towns of Sedalia and Knob Noster, Missouri, was chosen to be the home of the fourth Minuteman wing - Wing IV. Formerly the Sedalia Army Airfield, the base had seen extensive use by the Army Air Corps during the Second World War. The 351st Bombardment Group, previously active from 1942-1945 and from 1948-1949, had served with the Eighth Air Force in Europe and took part in bombing raids on Germany, hitting industrial and military targets critical to the war effort. Developed in the late 1950s and early 1960s, the LGM-30A Minuteman I weapons system entered service with Strategic Air Command (SAC) in October 1962, at the height of the Cuban Missile Crisis. It was the first solid-fuel ICBM to be used by the US, and was far more stable and less dangerous to work with than previous systems. It was decided to base them underground like the Titan force instead of above ground, to give the missiles greater survivability. Most of the earlier Atlas missiles were deployed on launch pads, making them highly vulnerable, and took hours to prepare. The deployment of the Minuteman system happened to coincide with the phasing out of the B-47 SAC's primary medium bomber. The more sophisticated and powerful B-52 was destined-to become the standard U.S. long-range bomber for the next several decades. However, to adapt the runways and other facilities to the larger, heavier B-52 was a costly proposition. Most of the bomber force was in fact distributed among bases along the northern tier of states, thereby shortening the flying distance to the Soviet Union via the Arctic. 

A decision was made not to assign the new aircraft to Whiteman. It would be re-designated as a Minuteman missile installation to become a member of the so-called "underground Air Force." Minuteman was conceived as a more efficient and less faulty system that would provide SAC with a survivable and lethal ICBM force that possessed true second-strike capability. In 1959, the Ogden Air Logistics Center at Hill Air Force Base, Utah, was made the program manager for the Minuteman. In 1962, the 351st was reactivated as the 351st Strategic Missile Wing, with Whiteman AFB as its headquarters. On June 14, 1961, the U.S. Government announced that Whiteman would serve as a support base for the fourth Minuteman strategic missile wing. After the announcement, there were second thoughts about the choice as original plans called for launchers to be spread into the Lake of the Ozarks region. Due to the terrain inaccessibility and the high water table, these plans were scrapped. Consequently, when the final approval came on January 17, 1962, the launchers were placed in the vicinity of Whiteman, making this the smallest Minuteman base with regard to area.

Above: A map of the now-deactivated 150 Launch Facilities and Launch 

Control Facilities in Western and Southwestern Missouri. (NUKEWATCH)

In February 1962, the Los Angeles-based Corps of Engineers Ballistic Missile Construction Office established a resident office at Whiteman. Meanwhile, the Real Estate Division of the Corps of Engineers Kansas City District set up an office in Sedalia to acquire the needed land. In January 1962, several construction companies - Morrison-Knudsen, Paul Hardeman, Inc., Perini Corporation, and C.H. Leavell and Company - were awarded the contracts for building the new missile facilities. Ground-breaking ceremonies took place at Whiteman in the spring of 1962 at the site where the Oscar-01 LCF would be built. The excavation of more than 2,000,000 cubic yards of earth began soon afterwards. 168,000 cubic yards of concrete, 25,355 tons of reinforced steel, and 15,120 tons of structural steel were used to complete the project. Although construction commenced on April 2, official groundbreaking ceremonies occurred on April 14, 1962, with several congressmen and Governor John Dalton joining military officials at the event. The enormity of the ensuing construction effort encompassed not only installing 150 silos and 15 launch control complexes but also constructing/reconstructing numerous roads and bridges throughout rural western Missouri. The "Hardened Intersite Cable System," measuring some 1,777 miles, connected the launch control centers and required land rights-of-entry from more than 6,000 landowners. During construction, management-labor relations were described as "excellent." With the exception of ironworkers, the local region supplied the project's manpower needs. There were five work stoppages, of which three involved union jurisdiction disputes. 

The Federal Mediation and Conciliation Service resolved one dispute while the others were handled at lower levels. In addition, there were only 11 "time-lost" injuries; no fatalities. In total, the construction project took two years, two months and two weeks to complete. The Launch Facilities were located at a minimum separation of 3 miles between each LCF, which created a missile complex of approximately 10,000 square miles at Whiteman AFB. The sites themselves were a far cry from their Titan and Atlas counterparts, which were primitive for their time. Minuteman was conceived as a more efficient and less faulty system that would provide SAC with a survivable and lethal force that possessed true second-strike capability. For this reason, completely different facility designs were drawn up. Instead of being located inside the silo, the launch control sites would be separate facilities, far apart from the launch sites. A total of 15 LCFs were slated for construction throughout remote parts of rural Southwest Missouri - in Johnson, Pettis, Cedar, and Benton. Above the bottom of where the capsule was to be built, a 25 feet deep excavation was done that created a rectangular space 100 feet long and 50 feet wide, and a second excavation would make a 20-foot cut 4 feet and 6 inches also above the capsule. A typical Minuteman control center is around 59 feet long and 29 feet wide, and the construction crews worked diligently and around the clock to complete the daunting task they had been given. 

An iron rebar frame around what would eventually become the LCC capsule was created, and afterwards came a mold built around it that aided in pouring the concrete. A total of 51 cubic yards of it were used for the tunnel walls and roof alone. A 10 square foot shaft next to the capsule that would be where the elevator and access ladder were located was made after the capsule was completed. The concrete walls were four feet thick, with the outer walls being ¼ inch steel plate.The interior was suspended on shock absorbers in order to prevent the LCC from shaking in the event of a nuclear strike. Depending on the depth of the capsule, it would take three or four lifts to complete the shaft. Around the outside edges of the structure, 228 cubic yards of concrete were poured through holes in the liner plate. Braces for the capsule walls and ceiling along with the structural steel floor and sleeve for the escape tube were added afterward. The new blast door, of a different design and size than the ones in Titan facilities, would be lowered down the elevator shaft and tunnel. It was assembled off-site, and then taken to where the excavation was occurring, where it was installed, prior to the completion of the access tunnel.






Above: a typical Minuteman II LCC under construction.




The largest use of concrete was on the upper capsule, where more than 500 cubic yards would be poured. The final adjustments for the blast doors were made and control panels and airliner for the shock isolators were installed, as well as the hydraulic system and pipes for the water cooling tank. A sand cushion lined the spot where the LCC would be. Sites assigned to the wings at Malmstrom and Minot had their emergency generators located above-ground. This meant that in the event of a nuclear strike, the capsule would be without power and unable to communicate with other flights and squadrons. SAC decided to alter the design of the LCFs for Wings III-VI. The regular generators, emergency power generators and life support systems were located underground in a second capsule next to the LCC - The Launch Control Equipment Room, or LCER. Wings III, IV-VI would incorporate revised construction techniques, at which point the LCER was buried underneath the surface, alongside the Launch Control Center itself. Once the LCC was completed, the Launch Control Support Building (LCSB) was next. All the necessary utilities, including the telephone lines and electrical circuits that connected to the LCC, water pipes and air conditioning were installed inside walls five feet deep, and reinforced concrete would be poured. In order to blend in with the landscape, the LCSBs were made to look like ‘ranch’-style houses, typical of the period.




LAUNCH FACILITY CONSTRUCTION






June, 1962: Crews install the reinforced liner

at the B-11 site northeast of Sweet Springs.




The Corps of Engineers Ballistic Missile Construction Office (BMCO) planned to build 150 silos in the area surrounding Whiteman. On June 10, 1963, the Army Corps of Engineers and civilian construction contractors turned the first flight of silos over to the Air Force Site Activation Task Force (SATAF). Over the next 5 months SATAF received responsibility for making final installations on the rest of the silos in preparation for final turnover to SAC. The keys to the final flight of silos were turned over to SATAF and the integration contractor (Boeing) on November 26, 1963. Compared to the SM-65 Atlas F sites, which stood a whopping $3.6 million, Minuteman silos were much cheaper to build, with a price tag of $500,000. Construction of the LFs began with a 12 feet deep cut, then a 70 feet cut for the Launcher Support Building and then a 34 feet deep circular cut for the Launcher Equipment Room. A 62 foot prefabricated steel liner with a quarter inch plate ringed with concentric rings of rebar was then lowered. Below the 34 feet deep cut, a shaft 52 feet deep was excavated that was out to 16 feet in diameter. Once the silo liner was aligned, concrete was then pumped around it to form the external missile silo wall. After the engineers completed the silo, the underground launch equipment and Launch Facility Support Building were constructed, at which point the excavation site was back filled. Until the desired depth was reached the crews would use sticks of dynamite to prevent overbreak from occurring, and the walls were dressed with pneumatic spades. Four feet of reinforced concrete and reinforcing bars made the foundation of the launcher tube. 

Three cranes placed the liner’s lower half 18 feet above the deflector plate. 52 feet long and 12 feet in diameter, the tube itself had five spider braces to ensure it maintained its circular shape as it was transported to its final destination. Welded to the tube were various plates, including the 10 feet high plates for the suspension system. Three different attachment points were located around the circumference at around 90, 210, and 330 degrees. A seven feet long concrete ‘collar’ was poured, through vertical pipes known as tremies, extending to between the liner and bottom of the shaft, delineating the liner. Once the silo liner was aligned, concrete was then pumped around it to form the external missile silo wall. Several backfills were done, the final one resulting in the lid being rested on track wheels and steel shrouds were placed around it. Once the engineers completed the silo, the underground launch equipment and Launch Facility Support Building were constructed. A backup diesel generator, fuel tank and water cooling unit for the LSB was lowered and a hydraulic unit and hatch cover installed. Through a gap in the ceiling, the frame for the LER was lowered and stringers at the lower part of the launch tube, raised by cranes and welded. After the seams were welded together and the two sections were connected a water stop was then installed.




SOURCES: HISTORIC AMERICAN ENGINEERING RECORD, MINUTEMAN FAMILIARIZATION, BOEING, NATIONAL PARK SERVICE