Minuteman Launch Facility S-05 (Sierra-05 LF), Lyman Nebraska

S-05 is a good reminder that the most consequential parts of the missile field often left the least dramatic surface trace. From public roads, a Peacekeeper launch facility could look like a fenced utility compound in farm-and-ranch country. Underground, however, S-05 belonged to one of the most heavily modernized ICBM forces the United States ever deployed: Sierra Flight, controlled from S-01, and later converted from Minuteman service to the LGM-118A Peacekeeper.

Launch Facility S-05 was an unmanned missile launch facility assigned to Sierra Flight in the F.E. Warren Air Force Base missile field. Its parent control site was the S-01 Missile Alert Facility / Launch Control Center. The site code is S-05. A secondary public photo-and-coordinate source identifies the site as Francis E. Warren AF Missile Site S-05, PIN 8705, ILC GHZL.

S-05 belonged to the 400th Strategic Missile Squadron during the Strategic Air Command era and later to the 400th Missile Squadron lineage in the 90th Missile Wing. It began as part of F.E. Warren's LGM-30B Minuteman I force, was later part of the base's LGM-30G Minuteman III field, and then was converted for the LGM-118A Peacekeeper missile. It is no longer an active missile site. The Peacekeeper strategic-alert mission ended on 2005-09-19, when the Air Force announced that no Peacekeeper ICBMs remained on strategic alert in the 400th Missile Squadron.

S-05 was one of ten launch facilities assigned to S-01 and Sierra Flight. Sierra Flight occupied a spread of rural launch sites in southeastern Wyoming near Yoder, Lyman, Huntley, Hawk Springs, and surrounding Goshen County countryside. That dispersion was not incidental scenery; it was the basic defensive geometry of the Minuteman and Peacekeeper field. Launch facilities were separated from one another and from their control site so that one strike could not eliminate an entire flight.

The immediate setting of S-05 is rural Goshen County, near the Wyoming-Nebraska state line. Its map position places it southeast of Yoder and west-southwest of Lyman, Nebraska. The site sat within an agricultural landscape where missile infrastructure, county roads, rail lines, irrigation, stock wells, and farmland all existed in close proximity. That mixture of ordinary land use and extraordinary military purpose is central to understanding F.E. Warren's missile field, the launch facilities were not clustered on the main base, but dispersed into civilian rural geography.

The 2000 Final Environmental Impact Statement for Peacekeeper Missile System Deactivation and Dismantlement places S-05 among the Peacekeeper launch facilities located within the Goshen Hole Lowlands. The EIS describes the Goshen Hole as a widening of the North Platte River system formed by erosion of softer sedimentary rock in the Brule-Arikaree Formation down toward harder underlying formations. For S-05, that matters because the site was not only a Cold War weapons location; it was also a parcel of real terrain with soils, groundwater, drainage, and post-deactivation land-use implications. A typical launch facility in the former Peacekeeper group consisted of a launcher and launch facility support building inside a security fence. The 2013 environmental assessment states that Peacekeeper launch-facility sites averaged approximately 1.6 acres, with an interior about 90 feet deep, a 28-foot headworks section, and a 12-foot-diameter launch tube below the headworks.

The Peacekeeper system was retired after the Cold War as U.S. strategic-force requirements changed and arms-control limits reduced the role of multiple-warhead ICBMs. Air Force public reporting stated that the Peacekeeper mission ended at F.E. Warren on 2005-09-19. At the deactivation ceremony, a missile combat crew officer at Papa-01 confirmed that no Peacekeeper ICBMs remained on strategic alert in the 400th Missile Squadron.

The 2013 Final Environmental Assessment for Minuteman III and Peacekeeper Silo Elimination gives the best public description of what happened to former Peacekeeper launch facilities such as S-05 after missile retirement. The assessment states that Peacekeeper missiles within the former 400th Missile Squadron had been removed, that previous deactivation activities included removal of missiles and salvageable items, that fluids had been drained from fueling, coolant, and hydraulic systems, and that electrical filters, switches, and power-supply batteries had been removed. After deactivation, gates were secured and each launch facility was placed in caretaker status.

New START then shaped the physical end of the site as a missile launch facility. Air Force Global Strike Command public reporting in 2011 stated that F.E. Warren would eliminate 50 former Peacekeeper missile silos and five associated alert facilities under the treaty. The 2013 environmental assessment evaluated dismantlement of those 50 Peacekeeper launch facilities and five MAFs. It described launch-facility elimination as removal of the headworks, blast door, launcher closure door, and related surface features, followed by filling, grading, and revegetation. The assessment also stated that each launcher would be open for national technical means observation before dismantlement and open for a 60-day observation period after the headworks were dismantled before final filling and grading.

For the full Sierra Flight narrative, see S-01 Missile Alert Facility / Launch Control Center

Cronology

• 1963-07-01 - The 90th Strategic Missile Wing was activated at F.E. Warren AFB.
• 1964-07-01 - The 400th Strategic Missile Squadron was organized during F.E. Warren's Minuteman expansion.
• 1965-06 - F.E. Warren's Minuteman field reached full operational status at the wing level; S-05 is treated as part of that mid-1960s operational Minuteman field.
• 1973 - F.E. Warren began converting its Minuteman force from Minuteman I to Minuteman III; the 400th Strategic Missile Squadron became the first all-Minuteman III squadron in the wing.
• 1974-09-03 - The 90th Strategic Missile Wing removed its last Minuteman IB from alert status.
• 1982-11-22 - President Ronald Reagan announced plans to deploy the MX / Peacekeeper missile at F.E. Warren.
• 1984-07 - Construction began for Peacekeeper support facilities at F.E. Warren.
• 1986-01-23 - The 400th Strategic Missile Squadron began phasing out Minuteman III missiles in preparation for Peacekeeper deployment.
• 1986-10-10 - The 90th Strategic Missile Wing recorded its first strategically postured Peacekeeper site.
• 1986-12-16 - The 90th Strategic Missile Wing reached initial operating capability for the Peacekeeper system.
• 1988 - F.E. Warren's public wing history states that 50 Peacekeeper missiles were brought on alert in modified Minuteman III silos.
• 2005-09-19 - The Peacekeeper alert mission ended at F.E. Warren; Air Force public releases stated that no Peacekeeper ICBMs remained on strategic alert in the 400th Missile Squadron.
• 2007-06 - The 2013 silo-elimination environmental assessment bibliography lists a Toltest, Inc. Tank Closure Report for Launch Facility Sierra-5, F.E. Warren AFB, Wyoming.
• 2011-02-05 - New START entered into force, setting treaty deadlines that shaped elimination of deactivated silos and associated alert facilities.
• 2013-03 - The Final Environmental Assessment for Minuteman III and Peacekeeper Silo Elimination evaluated dismantlement of 50 Peacekeeper launch facilities and five MAFs assigned to F.E. Warren AFB.
• 2013-08-04 - A secondary public photo source posted S-05 field photographs labeled general view, wind vane, and HICS marker sign.
• 2018-02-04 - New START's elimination deadline applied to selected deactivated silos and associated alert facilities.

Read about the Peacekeeper Missile at F.E. Warren AFB

All Peacekeeper Missile Silo Locations

All Minuteman/Peacekeeper Missile Silo Locations