STRUCTURE AND OVERVIEW OF THE PROTOCOL

The Throw-weight Protocol consists of a preamble and two Sections and specifies the procedures used to determine the accountable throw-weight of each type of ICBM and SLBM.

PREAMBLE

The Preamble identifies the United States and the Soviet Union as the Parties to the Protocol and records the Parties' agreement that the procedures governing the determination and accountability of ICBM and SLBM throw-weight set forth in the Protocol are the procedures for such purposes applicable to the Treaty.

SECTION I - DETERMINATION AND ACCOUNTABILITY OF ICBM AND SLBM THROW-WEIGHT

Section I, consisting of seven paragraphs, sets forth the procedures for determining the accountable throw-weight for existing and new types of ICBMs and SLBMs. Procedures for notification of throw-weight data and resolution of disputes on throw-weight are also provided.

Paragraph 1 consists of two subparagraphs that set forth rules for determining the throw-weight of ICBMs or SLBMs demonstrated during flight tests. These rules are based on two distinct missile design types: those that carry more than one reentry vehicle (RV) and dispense them from the final stage (subparagraph a); and those that do not, i.e., those that carry more than one RV and dispense them from a self-contained dispensing mechanism (commonly referred to as a post-boost vehicle) and those that carry only one RV and dispense it from either the final stage or a self-contained dispensing mechanism (subparagraph b).

The phrase "ICBM or SLBM the final stage of which executes a procedure for dispensing reentry vehicles," used in subparagraph (a), is a defined term. The definition of the term makes it clear that an ICBM or SLBM qualifies as a missile of this design (type a) the first time it conducts a flight test with more than one RV during which the missile's final stage (using either a main or vernier engine of the final stage), rather than a self-contained dispensing mechanism (SCDM), executes a "procedure for dispensing reentry vehicles."

The phrase "procedure for dispensing reentry vehicles" used in subparagraph (a) also is a defined term. The definition specifies that a simulated release of an RV is considered to be the same as an actual release of an RV. Thus, a missile that carried more than one RV would qualify as a "type a" missile even if it released no actual RVs from the final stage, but simulated the release of an RV from the final stage.

The first part of the definition of "ICBM or SLBM the final stage of which..." also incorporates a type rule, the legal effect of which is that once a missile qualifies as a missile of this type during a flight test, it remains a missile of this type, even if on all subsequent flight tests it carries only one RV. The second part of the definition of this term specifies that an individual missile which is of a type that has carried more than one RV and has executed a procedure for dispensing RVs, but does not otherwise qualify as a "type a" design (having dispensed such RVs from a SCDM), would be considered to be of such a design for purposes of determining its throw-weight if, during a flight test, it released an RV or penetration aid prior to termination of main engine thrust of the final stage. The purpose of this provision is to make certain that the throw-weight of a multiple-RV missile that incorporates a SCDM includes the weight of the final stage, including its unexpended fuel, for any flight test where such a missile releases an RV or penetration aid during the operation of the final stage, instead of during the operation of the SCDM (see below for discussion of how throw-weight is calculated for type "a" and "b" missiles). If, during that flight test, the missile demonstrates a greater throw-weight than that demonstrated on previous flight tests, then such greater value becomes the accountable throw-weight for all missiles of that type.

Subparagraph (a) specifies that for an ICBM or SLBM whose final stage executes a procedure for dispensing reentry vehicles, its throw-weight shall consist of: (1) the aggregate weight of the final stage, including its propellant and elements that have not separated from the stage, at the time when the first RV or penetration aid is released, whichever occurs first; and (2) the weight of the payload. "Payload" is a defined term. It includes, for a stage, the weight of everything that separates from that stage -- penetration aids, RVs, telemetry package, etc. -- beginning at the time when the velocity of the final stage is equal to 1,000 meters per second less than its velocity at the time of the earlier of two events: termination of main engine thrust of the final stage; or the first release of a reentry vehicle or penetration aid. Specifically excluded from the definition of payload, and hence from throw-weight, is the weight of the front section shroud (also referred to as the aerodynamic shroud) and the propellant burned by the final stage. The front section shroud is excluded, at Soviet insistence, on the grounds that it is designed to provide protection to the elements of the missile's front end during the missile's ascent through the Earth's atmosphere and is not directly related to useful military payload (although the testing of heavy shrouds might be used to validate additional throw-weight capability). The burned propellant of the final stage is excluded because, for "type a" missiles, a specific portion of the propellant already is captured as throw-weight in the language of paragraph 1(a), and for "type b" missiles, the propellant is not used to "execute a procedure for dispensing reentry vehicles."

The 1,000 meters per second criterion is incorporated to avoid a specific circumvention scenario. If mass that separates from the final stage is considered to be throw-weight only after thrust termination, then mass could be released just prior to thrust termination and not be captured as throw-weight. This would be true despite the fact that such mass could potentially fly to a militarily useful range and could be used to test the effect of heavier military payloads. Allowing such testing even with inert mass (e.g., mass that is not a reentry vehicle or penetration aid), but not capturing it as throw-weight (which otherwise would be reflected in the missile's accountable throw-weight), could conceivably support a breakout potential (since such inert mass could be converted quickly to useful military payload without having to undergo a time-consuming testing program to gauge the effect of additional throw-weight on missile performance.) Mass released prior to the point when the final stage velocity is 1,000 meters per second less than at thrust termination need not count as throw-weight, since mass released this early in the missile's trajectory could not be used effectively to test a missile's performance characteristics when carrying heavier payloads to a militarily useful range.

In the view of the United States, and we believe in the view of the Soviet Union as well, subparagraph (a) was negotiated for the purpose of determining the throw-weight of a unique missile design represented by only one type of missile, the Soviet SS-N-23. However, late in the negotiations, after the language of this subparagraph and its associated defined terms had been largely agreed, the Soviets declared that they possessed no missiles of "type a" design, including the SS-N-23. In a July 29, 1991 statement, the United States declared that while it would allow the throw-weight of the SS-N-23 to be calculated as if it were not a "type a" missile, it reserved the right to contest in the Joint Compliance and Inspection Commission the throw-weight values of any new type or modified existing type of ICBM or SLBM that incorporated a design similar to the SS-N-23, if such throw-weight values are based on subparagraph (b). (See the discussion of "Other Statements" in this analysis.)

Subparagraph (b) provides that for ICBMs and SLBMs whose final stage does not execute a procedure for dispensing reentry vehicles (i.e., those that carry more than one reentry vehicle and dispense them from a self-contained dispensing mechanism, and those that carry only one reentry vehicle and dispense it from either the final stage or a self-contained dispensing mechanism), the throw-weight shall be the weight of the payload of the final stage or final stages. The phrase "final stages" is intended to clarify that if in the future a missile were to incorporate a design that utilized more than one final stage, the payload of all such final stages would be included as throw-weight.

Finally, although Paragraph 1 refers to throw-weight in terms of the "weight" of various elements of a ballistic missile, rather than their "mass," the Parties understood that, for purposes of the Throw-weight Protocol, the term "weight" is equivalent to the term "mass." On February 27, 1991, Soviet negotiators made a formal statement for the record that, for the purposes of determining throw-weight, "weight" meant static weight at sea level on the surface of the Earth. This statement was subsequently accepted by U.S. negotiators.

Paragraph 2 provides that for ICBMs and SLBMs of existing types (that is, existing as of entry into force), the accountable throw-weight will be the greatest throw- weight demonstrated in flight tests of an ICBM or SLBM of that type. This means that the rules of paragraph 1 will be applied to existing types and that their accountable throw-weight, for purposes of Treaty limitations, can increase, even after entry into force, above the values specified in Section I of the Memorandum of Understanding, up to a limit described below.

Paragraph 3 provides that for ICBMs and SLBMs of a new type, the accountable throw-weight, like that of existing types pursuant to paragraph 2, will be the greatest throw-weight demonstrated in flight tests of an ICBM or SLBM of that type. However, for new types, the determination of accountable throw-weight is subject to two additional provisions.

First, subparagraph (a) provides that for ICBMs and SLBMs of a new type, the greatest throw-weight demonstrated in flight tests must be no less than the maximum calculated throw-weight (to be determined pursuant to paragraph 4 of this Section) that an ICBM could deliver to 11,000 kilometers and that an SLBM could deliver to 9,500 kilometers. This provision is designed to prevent a Party from establishing an accountable throw-weight for a new missile that is significantly less than its actual throw-weight potential.

Second, subparagraph (b) provides that the first seven flight tests for ICBMs and SLBMs of a new type will not be used to determine the greatest throw-weight demonstrated if none of those seven flight tests exceeds, by more than 20 percent or 250 kilograms, whichever is less, the greatest throw-weight demonstrated in flight tests that are subsequent to the first seven flight tests but prior to an ICBM or SLBM of the type becoming subject to the limitations of Article II of the Treaty. Since design changes can occur early in a missile's flight test program that can affect its performance characteristics, this provision is designed to ensure that the missile's accountable throw-weight reflects the missile's deployed throw-weight. This addresses a Soviet concern that a missile not be accountable for a throw-weight value demonstrated during initial testing, of which it might not actually be capable once deployed. In addition, this provision compensates for Soviet flight test programs that incorporate additional telemetry packages on early tests that are flown to less than operational range. Note that pursuant to the Thirty-second Agreed Statement, if a Party deploys a new type of ICBM or SLBM prior to the eighth flight test, its accountable throw-weight will be subject to discussion and agreement in the JCIC.

Paragraph 4 prescribes the method for determining a missile's maximum calculated throw-weight, i.e., the maximum throw-weight that an ICBM or SLBM of a new type could deliver to a specified distance under a specific set of assumptions. It provides that the Party developing such a missile will use its own methods for such calculation, subject to five assumptions that decrease computational complexity and standardize the results. These five assumptions are:

First, the distance to which the throw-weight is delivered will be measured along the missile's flight trajectory projected onto the Earth's surface from the launch point to the point that a reentry vehicle is projected to impact on the Earth. For purposes of projecting the reentry vehicle's impact on the Earth, the reentry vehicle shall be considered to have been released immediately after termination of the main engine thrust of the final stage.

Second, the Earth will be considered to be spherical and non-rotating. This assumption standardizes the results of the throw-weight calculation by factoring out irregularities in the Earth's surface and variances in launch site location and launch azimuth.

Third, the reentry vehicle's projected impact on the Earth will be calculated as though that vehicle followed a ballistic trajectory in a vacuum. This assumption eliminates the need to account for relatively minor atmospheric effects during reentry.

Fourth, the distance will be calculated based on each stage having a full propellant load.

Fifth, the propellant in each stage that remains after that stage has terminated its thrust will be no greater than one percent for solid-propellant ICBMs or SLBMs or two percent for liquid-propellant ICBMs or SLBMs. The fourth and fifth assumptions are intended to guard against deliberate undercounting of throw-weight capability.

While not stated as an explicit assumption, the Parties understand that, as a practical matter, maximum calculated throw-weight also implies a launch trajectory that will deliver the maximum throw-weight to the specified range, taking into account the performance characteristics and limitations of the new type of ICBM or SLBM. In other words, for a missile with a given set of performance characteristics and limitations, flown to a given range, there is a single launch trajectory that maximizes the throw-weight the missile is capable of carrying. The Parties did not specify the performance characteristics or limitations that are to be considered in determining the launch trajectory.

Paragraph 5 of Section I prohibits a Party from increasing the accountable throw-weight of an ICBM or SLBM of an existing type by more than 21 percent of the initial accountable throw-weight, as reflected in Section I of the Memorandum of Understanding. (If such throw-weight is increased by 21 percent or more and there is a change in the length of the first stage by five percent or more, the ICBM or SLBM in question would become a new type, and would be subject to the warhead counting rules for new types. See Agreed Statement Thirty-four.) This provides some flexibility to increase the throw-weight of an existing type, while strictly limiting the degree to which the warhead-carrying potential of such a missile could be increased. This is important because the Treaty prohibits increasing the number of accountable warheads on existing types of ICBMs and SLBMs.

Paragraph 6 provides that the Parties will exchange ICBM and SLBM throw-weight data in connection with the throw-weight Protocol in accordance with Section III of the Notification Protocol. Paragraph 6 also provides that throw-weight values will be measured in kilograms and will be rounded to the nearest multiple of 50.

Paragraph 7 provides that if a dispute arises concerning the initial value of accountable throw-weight of an ICBM or SLBM of a new type, or the increased value of accountable throw-weight of an ICBM or SLBM of an existing or new type specified in accordance with Section III of the Notification Protocol, then the accountable throw-weight will be the value specified in the notification until the dispute is resolved in the Joint Compliance and Inspection Commission. This provision merely clarifies that a dispute over the throw-weight value of an ICBM or SLBM will neither prevent such value from being recorded in the MOU, nor prevent the deployment of a new type of such ICBM or SLBM. The provision is without prejudice to a Party's right to charge the other Party with non-compliance in connection with a disputed throw-weight value.

SECTION II - VERIFICATION

This Section consists of three paragraphs setting forth procedures for verifying compliance with the Protocol and establishing the Protocol's legal status.

Paragraph 1 provides that national technical means of verification (NTM) will be used by each Party to verify the other Party's compliance with the Protocol.

Paragraph 2 requires a Party to conduct two pre-announced flight tests of an ICBM or SLBM of each new type prior to an ICBM or SLBM of that type becoming subject to the limitations provided for in Article II of the Treaty. These two pre-announced flight tests will be conducted either during the 12-month period prior to an ICBM or SLBM of that type becoming subject to the central limits provided for in Article II of the Treaty or during the last five flight tests prior to an ICBM or SLBM of that type becoming subject to the central limits provided for in Article II of the Treaty. A ballistic missile becomes subject to the Treaty's central limits when its associated launcher is considered to be deployed, pursuant to paragraph 6(c),(d),(f), and (g) of Article III. The alternate (last five flight tests) provision was included so that if initial deployment was delayed, a Party would not be forced to conduct an extra flight test(s) to meet the 12-month rule.

Paragraph 3 requires that no more than one of these pre-announced flight tests may be conducted in any 30-day period. Advanced notification of these flight tests will facilitate the preparation and orientation of NTM assets, thus enhancing verification of throw-weight values.

A final provision, like those in the other Protocols, provides that, pursuant to subparagraph (b) of Article XV of the Treaty, additional measures can be agreed upon by the Parties with respect to this Protocol to improve the viability and effectiveness of the Treaty. The Parties agree that, if changes need to be made in the Protocol that do not affect substantive rights or obligations under the Treaty, then such changes as are agreed upon shall be made within the framework of the Joint Compliance and Inspection Commission (JCIC), without resorting to the amendment procedures set forth in Article XVIII of the Treaty.

Pursuant to Article XVII of the Treaty, the Protocol is deemed to be an integral part of the Treaty.