323. Paper Prepared by the Verification Panel Working Group1

Approved Interpretation SLBM Limitations and Replacement

The Soviets may have no more than 740 SLBM launchers on nuclear submarines (H and Y class) unless they replace older ICBM’s in accordance with agreed procedures.
The 740 includes all ballistic missiles regardless of type on nuclear submarines.
It includes approximately 710 SLBMs on Y-class submarines and 30 on H-class submarines.
The number 740 was arrived at in the negotiating process as a compromise between different views of the number of SLBMs operational or under construction.
The purpose of “740” is to establish a clear and unambiguous baseline which avoids uncertainty or debate over the definition of “under construction” or our accepting a definition which may be unverifiable.
According to Article III, the next submarine on which construction begins will be a replacement boat. There is no agreement on the meaning of “under construction,” but it is not necessary since destruction of old systems doesn’t start until the replacement boat comes out of the construction hall. Therefore, the first SLBM on a Y-class boat off the ways after 710 will be a replacement. The older ICBMs or SLBMs it is replacing will be destroyed as the boat begins sea trials in accordance with agreed procedures.
The ultimate total of 62 modern submarines is a ceiling on the number of “operational” Y-class submarines. The total of 950 missiles is a ceiling on SLBMs on nuclear submarines plus modern SLBMs (SS–N–6 or 8) on older (i.e., G-class) submarines.
Additional boats and SLBMs above the ceiling can be under construction (by either side) as replacements for existing boats. The only explanation required for the new construction will be what is required by the notification procedures which have yet to be developed. We could not argue that Y-class cannot be replaced with new Y-class or the like—at some point in time we would face a problem with ULMS with this interpretation since we may have as many as ten boats (240 SLBMs) under construction in 1977.
Reaching the number 950 on Y-class submarines will require the Soviets to retire H-class launchers. They will also have to retire SS–7/8 ICBMs. They cannot build Y-class boats to replace launchers on G-class boats. G-class boats and SLBMs are completely outside the agreement unless they are modernized. Any modern SLBMs on G-class will be counted within the 950 ceiling.
The Soviets could retain older SLBMs on G-class boats in addition to their ceiling of 62 modern boats and 950 SLBMs. The Soviets could also retain SLBMs on H-class submarines (i.e., by having less than 950 launchers on the Y-class). But, the total of SLBMs on Y and H-class submarines and modern SLBMs on G-class submarines must be 950 or less.

  1. Source: National Archives, Nixon Presidential Materials, NSC Files, NSC Institutional Files (H-Files), Box H–011, Verification Panel Meeting SALT Submissions 6/7/72. No classification marking.