Last updated: March 22, 2023
Delta-09 Missile Silo
Historical/Interpretive Information/Exhibits, Information Kiosk/Bulletin Board, Parking - Auto, Parking - Bus/RV, Restroom - Accessible, Toilet - Vault/Composting, Wheelchair Accessible
“Minuteman-land is eerie. On the surface, no weapon is visible. But beneath the empty prairies and forested hills the gyroscopes are eternally spinning; these are the master navigators of jam-proof guidance systems, each ready to steer holocaustal destruction to a pre-selected target.”
~ John Hubbell, “The Missile That Closed The Gap,” Readers Digest, October 1962.
There is no better place to witness the Minuteman’s role in the Cold War than at Launch Facility Delta-09. From 1963 until 1991 Delta-09 contained a fully operational Minuteman Missile. The Delta-09 silo was one of 150 spread across western South Dakota. In total there were 1,000 Minuteman missiles deployed from the 1960's into the early 1990's. These nuclear sentinels waited silent and deadly to perform their destructive duty at a moment’s notice.
The Minuteman – Technological Wonder
The first Minuteman housed in Delta-09’s silo was the IB. The IB was part of the second evolution of the system. An improved encasement for the missile’s motor led to an effective increase in range from the 4,300 miles of its predecessor, the IA, to over 6,000 miles for the IB. The IB weighed over 65,000 pounds yet could travel at speeds in excess of 15,000 miles an hour. To put this speed into perspective, consider that a person driving across the continental United States will average 50 hours for the trip. If they instead piggybacked on a Minuteman their travel time would be cut to five minutes. A Minuteman could strike its intended target within the Soviet Union in less than 30 minutes.
In the early 1970's Minuteman II’s replaced the Minuteman IB in the 44th Missile Wing across western South Dakota. The missile housed in the Delta-09 Launch Facility today is a replica of the Minuteman II missile. The Minuteman II was considered a technological wonder at the time of its deployment. Upgrades had been made in order to improve precision and range of America’s existing ICBM force. The Minuteman II had a range of up to 7,500 miles, effectively placing it within reach of almost anywhere on earth. It had the capability to strike within 900 yards of its intended target.
The Minuteman – Technological Terror
Each Minuteman II carried a 1.2 megaton warhead. This singular weapon could wreak untold devastation upon an enemy, making it truly a technological terror. A 1.2 megaton warhead is equivalent to one million, two hundred thousand tons of dynamite. The Minuteman II’s warhead was sixty-six times more powerful than the atomic bomb that devastated Hiroshima, Japan and killed 140,000 people just before the end of World War II. One the most shocking statistics is that the Minuteman II’s warhead was more powerful than all the bombs the Army Air Force dropped on Europe in their successful bombing campaign that led to American victory in World War II.
A Minuteman II warhead's 1.2 megaton explosion would release an unprecedented amount of energy. Any structures at or near ground zero are immediately vaporized. The blast fireball is a mile in width. Those witnessing such an explosive force see a blinding light many times brighter then the noon day sun. A tornado like vortex with wind speeds of over 150 mph engulfs the surrounding area for miles. The residual effects of radiation contaminate not only the blast area, but also send radioactive particles swirling into the atmosphere. The destructive effects of a Minuteman’s warhead are so great that the United States vowed to only use these weapons if all other policy measures failed.
- Information and directions for visiting Delta-09
- Take a guided mobile phone tour of Delta-09
- Virtually explore the interior of Delta-09
Launch Facility Delta-09: The Early Years - From Minuteman IB to Minuteman II
Official construction of Delta-09 began in the latter part of 1961. Two years later Delta-09 was turned over to the Strategic Air Command (SAC) on 1 November 1963, making it one of the first Minuteman sites to be activated at Ellsworth. The Launch Facility housed a Minuteman IB missile from 1963 until the early 1970's. Between 1971 and 1973, facilities at Delta-09 were modified slightly when Ellsworth replaced its arsenal of Minuteman I missiles with the more advanced Minuteman II.
The most important changes associated with this conversion were contained within the missiles themselves, since Minuteman II featured a more powerful propulsion system and a more accurate guidance system than its predecessor. Changes included installation of new electronic ground-support equipment in existing racks at the Launch Facility; and the installation of electronic filters, seals, and circuit-breaking equipment at both sites to protect the facilities against damage from the electromagnetic pulses released by atomic blasts.
Security System Upgrade
The improved minuteman physical security system (IMPSS) antenna was installed at the launch site in 1989. IMPSS is a microprocessor-based surveillance system designed to detect outer zone intruders. It replaced troublesome older security systems so sensitive that they could be set off by "elk, rabbits, even high-jumping grasshoppers." A hardened UHF antenna, installed in 1968 to link the Launch Facility with the Strategic Air Command's airborne launch control center, is located a few feet to the northwest of the silo opening. It rests atop a thirteen-foot-diameter, reinforced-concrete base, shaped like an inverted saucer. The antenna itself is housed inside a cast-steel frustum capped with a conical, gray fiberglass weather dome.
Always Ready, Always Waiting - Ready For Launch
24 hours a day, seven days a week for 365 days a year Delta-01 was operational. No matter if there were white-out blizzards or 110 degree heat, operations at Delta-01 went on around the clock. Literally thousands of personnel lived and worked at the site for nearly three decades. This record of constant vigilance is astounding.
Delta-09 & Minuteman Missile National Historic Site - Preserving the Cold War
In September 1991, all 450 of the nation's Minuteman II missiles were taken off alert. Delta-09 was deactivated in early 1993 and placed on "caretaker status." Deactivation included the removal of classified electronic equipment, hazardous materials, environmentally sensitive materials, and equipment saved for use at other sites from Delta-09.
In 1993 the United States Air Force and the National Park Service initiated studies to determine whether Launch Control Facility Delta-01 and Delta-09 could be preserved as a unit of the National Park Service. On November 9, 1999 Congress designated Delta-01 and Delta-09 as Minuteman Missile National Historic Site and the bill was signed into law by President Bill Clinton.
Slight modifications have been made to Delta-09 to prepare it for interpretation as a static display. The launcher closure has been permanently fixed in a partially open position, in agreement with the START Treaty, and a glass and aluminum viewing enclosure was installed over the opening in 2001. A deactivated training missile was installed in the launch tube in 2001. The glass viewing enclosure allows visitors to see into the launcher to view the training missile.