RT-21 Temp 2S

RT-21 Temp 2S
Name	RT-21 Temp 2S
Origin	Soviet Union
Type	Intercontinental ballistic missile (ICBM)
Manufacturer	Moscow Institute of Thermal Technology; Soviet Strategic Rocket Forces
Service	Prototype testing (1970s)
Wars	None
Weight	~?
Length	~?
Payload	Multiple warhead capability (projected)
Propellant	Solid fuel (staged)
Guidance	Inertial guidance with planned astro-inertial updates
Launch platform	Road-mobile transporter erector launcher (TEL)

RT-21 Temp 2S was a Soviet-era solid-fuel intercontinental ballistic missile program developed during the 1960s–1970s as part of a broader strategic modernization effort by the Soviet Union. Conceived to provide road-mobile, rapid-reaction nuclear strike capability, the project intersected with contemporary developments in Strategic Arms Limitation Talks, Cold War deterrence theory, and competing systems such as the R-36 (missile) and RT-2PM Topol. The program influenced later mobile ICBM designs despite never entering full operational deployment.

Development and Design

Development began under direction from design bureaus and institutions tied to Soviet strategic weapons, including the Moscow Institute of Thermal Technology, with technical leadership overlapping work on the RT-2 family and early solid-propellant efforts influenced by lessons from the R-7 Semyorka and UR-100. Political sponsorship tied the project to ministries and planners in Moscow and the Ministry of Defense of the USSR, while operational requirements were shaped by commanders in the Soviet Strategic Rocket Forces seeking survivable, mobile launchers analogous to contemporary Western mobile concepts like those pursued by the United States for the Minuteman and earlier Polaris sea-based deterrents.

Design choices emphasized a two- or three-stage solid-propellant stack to reduce launch preparation time relative to liquid-fueled predecessors such as the R-12 Dvina. Road mobility centered on a transporter-erector-launcher (TEL) concept that required collaboration with heavy vehicle manufacturers in Moscow Oblast and specialists who had worked on the MAZ-543 chassis used by other Soviet mobile systems. Guidance architecture planned to combine inertial navigation with celestial fixes like those developed for the Soyuz and cruise systems, while warhead design considered multiple independently targetable reentry vehicles (MIRVs) akin to those deployed on the R-36M.

Specifications

Public technical data remain limited due to classification and program cancellation; many parameters are reconstructed from archival disclosures and Western intelligence estimates tied to programs contemporary to the project such as the SS-16 Sinner assessments. Reported attributes include a solid-fuel multi-stage missile with an estimated operational range in the ICBM class, throw-weight sufficient for single large warheads or multiple smaller vehicles, and TEL-based road mobility comparable to the SS-20 Saber in maneuverability. Propulsion development drew on solid motor advances from OKB-692 and tanked-stage lessons from the R-9 Desna program. Guidance was projected for improved circular error probable (CEP) over earlier solid designs through inertial and astro-inertial integration, referencing technical work associated with Kalinin-era inertial platforms.

Operational History

Flight-testing and prototype activities reportedly occurred during the late 1960s and early 1970s, overlapping with test programs at ranges such as Kapustin Yar and the Kura Missile Test Range in Kamchatka Krai. The program encountered technical, logistical, and political challenges, including vehicle weight and TEL integration issues observed in parallel programs like the SS-16 and R-36M2 efforts. Cancellation decisions were influenced by strategic arms negotiations and shifting priorities toward silo-based heavy ICBMs and mobile solid-fuel designs that proved more practical, such as the later RT-2PM Topol. As a result, the RT-21 program did not enter mass production or full service with the Soviet Strategic Rocket Forces.

Strategic Role and Deployment

Planners intended the missile to provide a survivable second-strike capability by dispersing mobile launchers across road networks, complicating targeting for NATO forces including commands such as Supreme Headquarters Allied Powers Europe and strategic intelligence assets like the National Reconnaissance Office and Central Intelligence Agency. Deployment concepts mirrored strategic debates reflected in the Strategic Arms Limitation Talks and later Strategic Arms Reduction Treaty negotiations, where mobile systems factored into balance calculations between the United States and the Soviet Union. Had it entered service, the system would have altered basing postures similar to impacts attributed to the deployment of the SS-20 Saber and the introduction of NATO responses including Pershing II posture changes.

Variants and Modifications

Planned variants reportedly included versions optimized for single-warhead maximum-range missions and MIRV-equipped configurations paralleling development paths seen in the R-36M family. Proposals addressed TEL chassis diversity, with potential adaptations on heavy-wheeled platforms related to the MAZ series and alternate rail-launch concepts considered in Soviet projects such as the BTS-4 studies. Research spin-offs informed solid-propellant motor technology later applied to systems like the RT-2PM Topol and influenced design choices in subsequent export and domestic programs handled by organizations including the Moscow Institute of Thermal Technology.

Assessment and Legacy

Although the missile did not see operational fielding, the program contributed technical and organizational lessons affecting later Soviet and Russian strategic forces. Innovations in solid-propellant techniques, TEL integration, and guidance system approaches carried forward into deployable systems such as the RT-2PM Topol and influenced design philosophy within bureaus like Tikhomirov NIIP and NPO Mashinostroyeniya. The project occupies a niche in Cold War historiography alongside other canceled or curtailed initiatives like the SS-16 Sinner and development trajectories that culminated in post-Soviet strategic systems. Its legacy persists in analyses by scholars affiliated with institutions such as Harvard University, King's College London, and think tanks that study nuclear strategy and arms control.

Category:Intercontinental ballistic missiles of the Soviet Union