Atlas F Site 577-5 Missile Silo, Manitou Oklahoma

Atlas F Site 577-5 was one of the twelve SM-65F Atlas intercontinental ballistic missile launch complexes assigned to the 577th Strategic Missile Squadron at Altus Air Force Base, Oklahoma. The site was the squadron's Site 5, located in Tillman County near Manitou in southwestern Oklahoma.

The site belonged to the 11th Bombardment Wing, which was redesignated the 11th Strategic Aerospace Wing on 1962-04-01, and to the 577th Strategic Missile Squadron, the Altus Atlas F missile unit. Atlas F launch complexes were self-contained vertical silo sites with an underground launch-control center at the complex itself rather than Minuteman-style unmanned launch facilities controlled from a separate remote Launch Control Center.

Site 577-5 is inactive and decommissioned as a military installation. Construction at the site began on 1960-06-13, the site was turned over to the Air Force on 1961-08-30, and the Altus Atlas F missile force became operational in early October 1962. The site remained part of the operational 577th Strategic Missile Squadron until the Atlas F weapon system was removed from service in 1965. Site 577-5 was decommissioned on 1965-03-25, the same date on which the 577th Strategic Missile Squadron was inactivated.

Its assigned operational missile was General Dynamics Atlas missile 82F, serial number 61-2568, Air Force tail number 568. The missile was accepted on 1962-05-23 and delivered on 1962-06-03. After its short operational ICBM service, the missile later entered the Atlas space-launch and test-vehicle stream. Atlas 82F was launched successfully from Vandenberg Air Force Base Gantry A-1 on 1974-06-28 with a BMRS / SFT-3 reentry-vehicle test payload.

The former launch complex is now non-federal, private property. No public reuse, museum operation, or authorized visitor program was found for Site 577-5. The site should therefore be treated as a decommissioned former missile complex on private land with no public access.

Location, Landscape, and Site Description

Site 577-5 occupies a rural agricultural setting north-northeast of Manitou, Oklahoma, in Tillman County. The location placed the site in the southwestern Oklahoma missile field that surrounded Altus Air Force Base. Official Altus AFB history states that the 577th Missile Squadron activated in 1961 to operate twelve Atlas F missile sites within a forty-mile radius of Altus. That dispersed pattern was essential to the Atlas F concept. It separated the launch complexes so that one attack could not easily destroy the entire missile force, while keeping them near enough to Altus for logistics, maintenance, communications, security response, crew support, and command administration.

The Manitou area gave the Air Force open land, road access, low surrounding population density, and enough distance from the parent base and neighboring missile sites to support a dispersed alert posture. Like the other Altus Atlas F launch complexes, Site 577-5 was not a small surface pad. It was a large underground engineered facility, built around a deep reinforced-concrete vertical silo and an adjoining underground control and equipment complex. Construction required a major excavation, heavy reinforced concrete, large mechanical equipment, underground rooms and passages, utility systems, environmental control, power generation, propellant systems, communications, fencing, and a controlled surface compound.

Atlas F was the vertical-silo member of the operational Atlas missile family. A typical Atlas F complex included a deep cylindrical silo, a large elevator-launcher, heavy silo doors, a below-grade launch-control area, connecting passages, environmental-control equipment, electrical and power systems, propellant and liquid-oxygen support systems, antenna and communications equipment, access roads, security fencing, and a surface compound. The Association of Air Force Missileers describes Atlas F as housed in a vertical silo with an adjoining control center, hardened to 100 psi overpressure, filled with RP-1 while on alert, loaded with liquid oxygen at the start of the countdown, and raised to ground level by a massive silo elevator before launch.

Strategic and Cold War Context

Site 577-5 existed because the United States was rapidly building a credible land-based nuclear deterrent during the early Cold War. The Atlas missile family was the first operational American intercontinental ballistic missile system. Atlas was developed in an era when Strategic Air Command still relied heavily on bomber aircraft, but national strategy increasingly required missiles that could reach intercontinental targets from the United States, remain on alert, and complicate Soviet attack planning.

The National Park Service describes Atlas as the United States Air Force's first operational ICBM and notes that Atlas E and Atlas F were deployed across the United States after Atlas D. At their peak, 132 Atlas sites were operational from December 1962 through May 1964, before the system was phased out in favor of Titan and Minuteman missiles. Atlas F represented the most survivable operational Atlas basing concept. Atlas D used more exposed launch arrangements, Atlas E stored missiles horizontally in semi-hardened coffin launchers, and Atlas F stored the missile upright in an underground silo-lift launcher. Atlas F still depended on liquid propulsion and a complex countdown, but its hardened vertical silo gave it more protection than earlier Atlas configurations.

The Atlas F missile used RP-1 kerosene fuel and liquid oxygen oxidizer. RP-1 could be kept aboard the missile while it was on alert, but liquid oxygen had to be loaded during the launch countdown. The missile then had to be raised from the silo before launch. This was a major improvement over less-protected early ICBM basing, but it was still more labor-intensive and slower than the solid-fueled Minuteman missiles that soon displaced Atlas. The system was therefore both advanced and transitional: a hardened strategic missile force built just before the United States moved to more survivable and quicker-reacting solid-fueled ICBMs.

The Altus missile field became operational at a historically significant moment. Official Altus AFB chronology states that the 577th Missile Squadron's Atlas F sites became operational on 1962-10-10, while USAF unit-history material lists SAC turnover and operational status on 1962-10-09. Either way, the force became operational immediately before the Cuban Missile Crisis reached its most dangerous phase. During that crisis, the operational Altus Atlas F force formed part of the United States' strategic nuclear-alert posture.

Construction and Activation

Construction of the Altus Atlas F missile field began under the larger national program to field hardened ICBM sites in the central United States. Official Altus AFB chronology states that construction began on the first of twelve Atlas F missile sites around Altus AFB on 1960-05-01. USAF unit-history material records that the Corps of Engineers, Tulsa District awarded the basic construction contract to Morrison-Knudsen and Hardeman and Associates, whose combined bid was just over $20.9 million. The same source records that land acquisition for the twelve launcher locations required condemnation actions involving hundreds of landowners in six counties around Altus.

The site was listed as Corps of Engineers Construction Site Number 11 and Air Force Operational Site Number 5. Building an Atlas F complex required excavation of the silo shaft, placement of reinforced concrete, installation of the steel launcher and elevator machinery, construction of the adjoining underground control area and equipment rooms, installation of mechanical and electrical systems, installation of propellant support systems, construction of surface support features, and integration of the launch equipment with the missile and Strategic Air Command procedures.

The Altus construction program was technically difficult because the Atlas weapon system was still evolving while sites were being built. USAF unit-history material describes the concurrency problem that affected Atlas construction generally: improvements in the missile and associated equipment required modifications to facilities already under construction. The Tulsa District kept the project moving through a priority paperwork system, but the same summary notes work stoppages, project-related fatalities, major on-site fires, and difficulty installing and testing propellant-loading equipment.

The site's assigned missile, Atlas 82F, was accepted on 1962-05-23 and delivered on 1962-06-03. The Altus Atlas F force then reached operational status in October 1962.

Missile System and Technical Role

Site 577-5 housed the SM-65F Atlas, later commonly identified as HGM-16F after the 1962 missile-designation changes. The Atlas F was a one-and-one-half-stage, liquid-fueled ICBM built by Convair/General Dynamics. It used a thin, pressurized stainless-steel airframe that had to remain pressurized to retain structural integrity. The missile family was technologically demanding but historically important because it gave the United States its first operational ICBM capability.

The National Park Service summarizes the Atlas F as the most advanced of the Atlas types, stored in a blast-proof silo-lift configuration and capable of being launched in roughly ten minutes. The Association of Air Force Missileers describes the Atlas F as using inertial guidance, housed in a vertical silo with an adjoining control center, and raised to ground level by the silo elevator after liquid oxygen loading. That configuration explains the physical character of Site 577-5: the essential structure was not simply a buried tube but an integrated launch complex with crew, control, power, propellant, communications, and elevator-launcher systems.

The publicly documented reentry system for Atlas E/F was the Mark 4 reentry vehicle carrying the W-38 nuclear warhead. The National Air and Space Museum describes the Mark 4 as used on U.S. Air Force Titan I and Atlas E/F ICBMs deployed in the early 1960s and states that it carried a W-38 nuclear warhead with a yield of about 3.75 megatons. The National Park Service gives a rounded Atlas F warhead yield of 4.5 megatons; this entry uses the Smithsonian's specific Mark 4/W-38 description as the more direct public-source reference for the reentry vehicle and warhead.

The Atlas F launch complex was crewed. Unlike later Minuteman launch facilities, which were normally unmanned and remotely controlled from separate launch-control centers, each Atlas F launch complex had its own underground crew and control functions. The Association of Air Force Missileers describes Atlas F combat crews as including two officers and three enlisted members, with crew tours of roughly twenty-four hours at the site and a longer duty cycle when briefings, travel, and turnover were included. Maintenance organizations, propellant technicians, power-production specialists, missile electronics personnel, nuclear weapons technicians, and security forces were all part of the operating system that kept the missile on alert.

Operational History

The 577th Strategic Missile Squadron was organized at Altus AFB in 1961 and operated twelve Atlas F sites around the base. Official Altus AFB history states that the squadron activated in June 1961 to operate the twelve Atlas F sites, and that the missile silos became operational on 1962-10-10. USAF unit-history material lists SAC missile operations for the squadron as operational on 1962-10-09 and records that the first Series F Atlas ICBM was placed on alert at the 577th SMS in early August 1962.

At Site 577-5, operational history would have centered on maintaining one Atlas F missile and its underground launch complex on nuclear alert. Crews monitored missile, facility, communications, guidance, power, environmental-control, security, and propellant-related systems. Maintenance teams and specialized technicians worked to keep the site serviceable, correct faults, and complete required inspections. Security personnel protected a remote nuclear-weapon launch site in an agricultural landscape, while crew transportation and logistics linked the site to Altus AFB.

The Atlas F system required constant attention. Even on alert, the missile was not a simple sealed weapon waiting passively in the silo. Atlas depended on pressure stabilization, electrical systems, environmental control, guidance-system readiness, power generation, communications links, propellant support, and trained crews capable of executing emergency war order procedures. Before launch, the crew would have loaded liquid oxygen, raised the missile on the elevator, and completed the launch sequence. This operational complexity helps explain why Atlas F had a short service life once solid-fueled Minuteman missiles became available.

The site's active period was brief but intense. It overlapped the Cuban Missile Crisis, the period when the United States placed strategic forces on heightened alert after Soviet missile deployments were discovered in Cuba. Squadron-level sources record that the Altus Atlas F force was part of the alert posture during the crisis. Site 577-5 should therefore be understood as part of the operational nuclear force that entered service just as Cold War tensions reached one of their highest points.

The missile assigned to Site 577-5, Atlas 82F / tail number 568, later launched from Vandenberg Air Force Base on 1974-06-28 with a BMRS / SFT-3 reentry-vehicle test payload. That event did not occur at the Oklahoma site, but it shows how at least some former operational Atlas missiles continued in test and space-related roles after the Atlas ICBM force was retired.

Deactivation and Disposal

The Atlas F system left service quickly because newer missiles offered better survivability, readiness, and operational simplicity. On 1964-11-19, Secretary of Defense Robert S. McNamara announced the phaseout of Atlas D, E, and F missiles. USAF unit-history material records that the 577th SMS had its first ICBM off alert on 1964-12-30, its last ICBM off alert on 1965-02-04, and its last ICBM shipped on 1965-02-10. The squadron was inactivated on 1965-03-25.

Missile removal, equipment removal, property transfer, environmental cleanup, and long-term private reuse would have occurred as separate post-operational processes. The assigned missile did not simply disappear as scrap; Atlas 82F later flew from Vandenberg in 1974.

Site 577-5 was retired before the later strategic-arms-control era that produced standardized treaty demolition and inspection procedures for modern ICBM silos. It was therefore not a START-era silo-demolition case. Its post-military history was instead shaped by surplus disposal, non-federal ownership, private land use, and environmental-restoration programs associated with Formerly Used Defense Sites.

The former site entered the federal environmental-restoration record. The USACE FUDS inventory lists MANITOU, ATLAS MISSILE NO. 5, K06OK0405, with three project entries: Site 01 BD/DR, Site 02 HTRW, and Site 03 MMRP. The U.S. General Accounting Office's 2001 Oklahoma FUDS table lists ATLAS MISSILE NO. 5, K06OK0405, Tillman County, as eligible with hazards and three eligible cleanup projects. ProPublica's DERP-derived Bombs in Your Backyard dataset lists ATLAS MISSILE NO. 5 at Manitou, Tillman County, as Low Risk. These records show that the former missile property remained part of the long afterlife of Cold War infrastructure after its operational mission ended.

Current Status and Site Use

Site 577-5 is a decommissioned former Atlas F launch complex on private property near Manitou, Oklahoma. It is not an active military installation, and no public museum, tour operation, or official interpretive program was found for the site. The site should be treated as private property with no public access unless an owner or lawful authority explicitly grants permission.

Public aerial imagery shows the former compound in a rural setting. The site appears to retain a recognizable launch-complex footprint, including the former access and surface compound area. Because no detailed current condition report was found, this entry should not assume that underground areas are accessible, intact, safe, or open.

Chronology

• 1960-01 Public announcements identified Altus AFB as the future hub for twelve Atlas F missile sites in southwestern Oklahoma and nearby Texas.
• 1960-05-01 Official Altus AFB chronology states that construction began on the first of twelve Atlas F missile sites around Altus AFB.
• 1960-06-13 Construction began at Atlas F Site 577-5 near Manitou, Oklahoma.
• 1961-06-01 The 577th Missile Squadron activated at Altus AFB to operate twelve Atlas F launch sites.
• 1961-08-30 Site 577-5 was turned over to the Air Force.
• 1962-04-01 The 11th Bombardment Wing was redesignated the 11th Strategic Aerospace Wing.
• 1962-05-23 Atlas missile 82F / serial number 61-2568 / tail number 568 was accepted.
• 1962-06-03 Atlas missile 82F was delivered for the Altus operational ICBM mission.
• 1962-08 USAF unit-history material records the first Series F Atlas ICBM at the 577th SMS placed on alert early in the month.
• 1962-10-09 USAF unit-history material lists SAC turnover and operational status for the 577th SMS missile force.
• 1962-10-10 Official Altus AFB chronology states that the Atlas F missile silos became operational.
• 1962-10 The 577th SMS Atlas F sites were on heightened alert during the Cuban Missile Crisis.
• 1964-05-14 A propellant-loading explosion destroyed squadron Site 577-6 near Frederick, Oklahoma; this did not occur at Site 577-5.
• 1964-11-19 Secretary of Defense Robert S. McNamara announced the planned phaseout of Atlas D, Atlas E, and Atlas F missiles.
• 1964-12-30 USAF unit-history material records the first 577th SMS ICBM removed from alert.
• 1965-02-04 USAF unit-history material records the last 577th SMS ICBM removed from alert.
• 1965-02-10 USAF unit-history material records the last 577th SMS ICBM shipped.
• 1965-03-25 Site 577-5 was decommissioned and the 577th Strategic Missile Squadron was inactivated.
• 1974-06-28 The former Site 577-5 missile, Atlas 82F, launched successfully from Vandenberg AFB Gantry A-1 with a BMRS / SFT-3 reentry-vehicle test payload.
• 2001 GAO listed ATLAS MISSILE NO. 5, K06OK0405, Tillman County, as eligible for potential inclusion in the FUDS cleanup program with hazards and three eligible projects.
• 2015-09-30 The USACE FUDS Oklahoma inventory listed MANITOU, ATLAS MISSILE NO. 5, K06OK0405, with BD/DR, HTRW, and MMRP entries.
• 2017 ProPublica's DERP-based Bombs in Your Backyard dataset listed ATLAS MISSILE NO. 5 at Manitou, Tillman County, as Low Risk.

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