START REDUCTIONS
Reductions to equal aggregate levels in strategic offensive arms, carried out in three phases over seven years from the date the treaty enters into force.
Specific, equal interim levels for agreed categories of strategic offensive arms by the end of each phase.
Central limits include:
-- 1,600 Strategic Nuclear Delivery Vehicles (SNDVs).
-- 6,000 accountable warheads.
-- 4,900 ballistic missile warheads.
-- 1,540 warheads on 154 heavy intercontinental ballistic missiles (ICBMs) for the Soviet side. The Soviets also agreed in a side letter to eliminate 22 SS-18 launchers every year for seven years to achieve this level.
-- 1,100 warheads on deployed mobile ICBMs.
-- Throw-weight ceiling of 3,600 metric tons.
DELIVERY VEHICLES
-- 1,600 ceiling on the number of SNDVs, comprising deployed ICBMs and their associated launchers, deployed submarine-launched ballistic missiles (SLBMs) and their associated launchers, and deployed heavy bombers.
WARHEADS
-- 6,000 accountable warhead ceiling, comprising the number of warheads attributed to deployed ICBMs and SLBMs, the number of long-range, nuclear-armed air-launched cruise missiles (LRNA) attributed to heavy bombers equipped for LRNA (see LRNA), and one warhead attributed to each heavy bomber equipped only for nuclear-armed gravity bombs and short-range attack missiles (SRAMs).
BALLISTIC MISSILE WARHEADS
-- Each ballistic missile warhead attributed to a missile counts as one under the 6,000 warhead ceiling.
-- No flight testing of missiles with RVs in excess of attributed number.
-- A quota of on-site inspections to verify that deployed ballistic missiles contain no more RVs than the number of warheads attributed to them.
-- Ban on new types of ICBMs and SLBMs with more than 10 warheads.
-- Ban on increasing warhead attribution on future types of ICBMs and SLBMs.
DOWNLOADING
-- The number of warheads on up to three existing types of ballistic missiles and their attribution under START may be reduced ("downloaded") up to a total of 1,250 RVs.
-- Each Soviet SS-N-18 may be attributed with 3 RVs; a total of 896 SS-N-18 warheads count toward downloading limit.
-- US Minuteman III may be reduced by 1 or 2 RVs.
-- Insofar as permitted by the 1,250 limit, up to 500 RVs may be downloaded on two other existing ballistic missile types (up to 4 RVs per missile).
-- Ban on downloading of new types. Ban on deploying a new type with more warheads than on a downloaded type (except for the Minuteman III and the SS-N-18). Ban on downloading of heavy ICBMs.
-- If an ICBM is downloaded by more than two RVs, it must be equipped with a new front section platform, and all old platforms destroyed.
HEAVY ICBMS
-- In addition to the requirement to reduce deployed heavy ICBMs and their warheads by 50 percent, other constraints on heavy missiles include: no downloading; no increase in launch weight or throw-weight; no mobile launchers for heavy ICBMs; ban on new types of heavy missiles. New heavy ICBM silo construction allowed, but only in exceptional cases for relocation or to replace eliminated heavy ICBM silos in extraordinary circumstances; never to exceed 154 such silos. Modernization and testing of existing heavy ICBM's can continue.
NEW TYPES OF ICBMS AND SLBMS
-- An ICBM or SLBM will be considered a new type of ICBM or SLBM if it meets any of the following criteria: change in number of stages; change in type of propellant; 10 percent change in missile or first stage length; 10 percent change in missile launch weight; 5 percent change in diameter; 5 percent change in first stage length combined with 21 percent increase in throw-weight.
-- Ceiling of 21 percent on permitted increases to throw-weight of existing types of ICBMs or SLBMs.
-- Warhead attribution for future types of ICBMs and SLBMs will be the maximum number of RVs tested and simulated, but no less than the number derived by dividing 40 percent of missile throw-weight by weight of the lightest RV tested on that type of ICBM or SLBM. Application of the 40 percent rule to new systems with unconventional front ends will be discussed at the JCIC.
HEAVY BOMBERS
-- Each heavy bomber counts as one SNDV. Each heavy bomber equipped only for nuclear weapons other than long-range nuclear air-launched cruise missiles (i.e., only for gravity bombs and SRAMs), counts as one warhead under the 6,000 limit. An agreed number of heavy bombers could be removed from accountability under the 1,600 SNDV limit by conversion to a non-nuclear capability. Heavy bombers equipped for long-range nuclear ALCMs (LRNA), will be distinguishable from other heavy bombers.
-- In exchange for not including the Tupolev 22-M (Backfire) bomber in START, the Soviet Union will make a politically-binding declaration that it will not deploy more than 300 air force and 200 naval Backfires and that these bombers will not be given intercontinental capability.
LONG-RANGE NUCLEAR AIR-LAUNCHED CRUISE MISSILES (LRNA)
-- Nuclear-armed ALCMs with a range in excess of 600 kilometers (LRNA) will be affected under START. New long-range conventionally-armed ALCMs that are distinguishable from nuclear-armed ALCMs are not limited in START and may be deployed on any aircraft.
-- For the purpose of counting against the 6,000 warhead limit, accountable warheads will be attributed to heavy bombers equipped for LRNA as follows: each current and future US heavy bomber equipped for LRNA will count as 10 warheads (except as noted below) but may actually be equipped for up to 20 LRNA. Each current and future Soviet heavy bomber equipped for LRNA will count as 8 warheads (except as noted below) but may actually be equipped for up to 16 LRNA.
-- The United States may apply the above counting rule to 150 heavy bombers equipped for LRNA; the Soviet Union may apply the above counting rule to 180 heavy bombers equipped for LRNA. For any heavy bombers equipped for LRNA in excess of these levels, the number of attributable warheads will be the number of LRNA for which the bombers are actually equipped.
-- Multiple-warhead long-range nuclear ALCMs are banned.
MOBILE ICBMS
-- Categories of permitted movements and associated notifications have been agreed.
-- Non-deployed mobile ICBMs and launchers will be limited numerically and geographically (see NON-DEPLOYED MISSILES below).
-- Soviet mobiles are: SS-24 and SS-25. For purposes of reciprocity the US Peacekeeper will be treated as mobile although it has never been tested as a mobile ICBM.
NON-DEPLOYED MISSILES
-- There will be a numerical limit of 250 on non-deployed ballistic missiles for all ICBMs of a type that has been flight tested from a mobile launcher; of those, no more than 125 may be non-deployed missiles for rail-mobile launchers. There also will be a numerical limit of 110 on non-deployed launchers for mobiles of which no more than 18 may be non-deployed launchers for rail-mobile ICBMs.
-- Other non-deployed ballistic missiles will not be subject to numerical limits, but there will be restrictions on their location and movement and they will be subject to data exchange requirements.
-- Various provisions are also agreed to inhibit rapid reload of ICBM launchers.
-- The sides have also agreed there will be no restrictions on the number of cruise missiles and other heavy bomber weapons. There will be limited restrictions on the location of LRNA.
EXEMPTIONS FROM TREATY LIMITS
-- 75 non-modern heavy bombers equipped for non-nuclear arms, former heavy bombers, and training heavy bombers.
-- 20 test heavy bombers.
-- 25 test silo launchers and 20 test mobile launchers at test ranges.
SLCMS
-- Sea-launched cruise missiles (SLCMs) will not be constrained in the START Treaty. However, each side will provide the other with a politically-binding declaration concerning long-range nuclear SLCMs, i.e., those nuclear SLCMs whose range is over 600 kilometers. In annual declarations, the planned maximum number of these deployed nuclear SLCMs for each of the following five Treaty years will be specified. The planned maximum number will not exceed 880 long-range nuclear SLCMs. Nuclear-armed SLCMs with a range of 300-600 kilometers will be the subject of confidential annual data exchanges. The sides will not produce or deploy multiple warhead nuclear SLCMs.
VERIFICATION
The Strategic Arms Reduction Treaty (START) was designed with verification in mind, and verification measures were negotiated in parallel with other aspects. Thus, the basic structure of the Treaty is designed to facilitate verification by national technical means (NTM). The START Treaty contains detailed, interlocking and mutually reinforcing provisions, which supplement national technical means to establish an effective verification regime. This regime provides for data exchanges and notifications on strategic systems and facilities covered by the Treaty, a ban on the denial of data from telemetry, twelve types of on-site inspection and exhibitions, continuous monitoring at mobile ICBM final assembly facilities, and cooperative measures. These elements are outlined below.
-- NATIONAL TECHNICAL MEANS (NTM) - START provides for the use of, and non-interference with, national technical means of verification, e.g. satellites. There are explicit provisions prohibiting interference with NTM, or use of concealment measures that impede verification by NTM.
-- TELEMETRY - Parties are prohibited from engaging in any practice that denies full access to telemetric information during missile flight tests, with certain limited exceptions. Moreover, Parties are obligated to exchange telemetry tapes, interpretative data and acceleration profiles for every test flight.
-- DATA EXCHANGE AND NOTIFICATIONS - Prior to Treaty signature, the sides will exchange data on numbers, locations, and the technical characteristics of START-accountable weapons systems and facilities and will provide regular notifications and data updates thereafter.
-- COOPERATIVE MEASURES - Seven times a year, either party may request the other to display in the open road-mobile launchers, rail mobile launchers and heavy bombers at bases specified by the inspecting Party. Additional cooperative measures may be requested following an operational dispersal.
-- CONTINUOUS MONITORING ACTIVITIES - START establishes continuous monitoring at the perimeter and portals of each side's mobile ICBM assembly facilities. The US has the right to establish a monitoring facility at Votkinsk, which is the final assembly facility for the SS-25, and at Pavlograd, which is the final assembly facility for the SS-24. The Soviet side has the right to monitor the Thiokol Strategic Operations facility at Promontory, Utah, the final assembly facility for the accountable stage of the Peacekeeper. Such monitoring would also be established at any future facilities at which mobile ICBM assembly takes place.
-- ON-SITE INSPECTIONS (OSI) - There are twelve types of OSI and exhibitions. These are: baseline data inspections, data update inspections, new facility inspections, suspect site inspections, reentry vehicle inspections, post-exercise dispersal inspections, conversion or elimination inspections, close-out inspections, formerly declared facility inspections, technical characteristics exhibitions, distinguishability exhibitions and heavy bomber baseline exhibitions.
-- COMPLIANCE - Compliance concerns may be raised by either side in the Joint Compliance and Inspection Commission (JCIC) or any other appropriate forum.
DATA DENIAL
-- Agreement to broadcast all telemetric information from test flights of ICBMs and SLBMs and to ban any practice (including encryption, encapsulation and jamming) that denies full access to telemetric information, with certain limited exceptions.
-- Requirement to provide full telemetry tapes, acceleration profiles, and certain specified interpretive information after each test flight of an ICBM or SLBM.
-- As a goodwill gesture, the sides agreed not to engage in encryption or jamming beginning 120 days after Treaty signature.
TREATY DURATION
-- Treaty will have a duration of 15 years, unless superseded earlier by a subsequent agreement.
-- If the sides agree, treaty may be extended for successive five year periods.
NON-CIRCUMVENTION/THIRD COUNTRY ISSUES
-- No transfer of strategic offensive arms (SOA) to third countries, except that there will be no interference with existing patterns of cooperation.
-- There will be no permanent basing of SOA outside national territory and no inspections outside national territory. Temporary stationing of heavy bombers overseas permitted, but certain notifications may apply. Port calls for SSBNs permitted.
Current as of May 21, 1996
Created July 29, 1991
Source: Arms Control and Disarmament Agency