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U.S. Navy Ship Design Project Numbers, 1946-1979
("SCB Numbers")

The following two tables list all the project numbers used by the U.S. Navy to identify its new ship designs
(including major conversions) between 1946 and 1979. 

U.S. Navy Ship Characteristics Board (SCB) Numbers, 1946-1964

Later U.S. Navy Design Project Numbers, 1965-1979


On 15 March and 29 November 1945 SECNAV established a Ship Characteristics Board (SCB) and defined its responsibilities. The term "ship characteristics" was defined as "embracing all qualities and features of a ship which determine or affect her capabilities for accomplishing the missions of her type," including "the complement, their battle stations, and all material facilities for fighting and maneuvering the ship and accomplishing her other designed functions." The objective of the SCB was "to insure that through timely recommendations to the Chief of Naval Operationsthe characteristics of all naval vessels (projected, building, and on hand) not only meet, but anticipate wherever possible, the requirements of all phases of naval warfare. Designs referred to the SCB for review from 1946 to 1963 (for Fiscal Year 1964) were assigned numbers in a single sequence that included some concept-only designs as well as designs intended to be built. The approved characteristics were promulgated in OPNAV 09010 (originally 9010) series instructions, the number after the decimal in this case designating the directive. Thus OPNAVINST 09010.100 of 14 June 1956 was the SCB directive (no. 100) that disseminated the approved characteristics for the design of the nuclear aircraft carrier ENTERPRISE (SCB 160). (There were also three later versions of this directive, 100A, 100B, and 100C, and a total of 16 changes for the four directives, none of which are listed here.)

A new numbering system came into effect 24 April 1963 for Fiscal Year 1965 and later; it is categorized instead of sequential. Numbers are of the form XXX.FY, e.g. 241.66 for CALIFORNIA, the DLGN of FY66. The basic three-digit number series were 001 cruisers, 100 carriers, 200 destroyers, 300 submarines, 400 amphibious, 500 mine warfare, 600 patrol, 700 auxiliary/tender, 800 service craft, 900 special purpose. The two digit suffix denoted the fiscal year under which the ship was to be built (concept work was began earlier, and ships were sometimes slipped to later fiscal years or sisters were built then). In effect, this new numbering scheme ratified the fact that the focus of the SCB numbers had changed from design and development to procurement and budget compliance, and concept-only designs had generally ceased to receive numbers. The functions of the Ship Characteristics Board were taken over by the Ship Acquisition and Improvement Council (SAIC, c1971-72) and the Ship Acquisition and Improvement Panel (SAIP, c1972-76) and the numbers became Shipbuilding Project (SBP) numbers. OPNAVINST 09010.300 of 4 Jan 1974, Development of Naval Ship Characteristics, implemented a new system in which CNO requiremenmts for ship designs were defined in a Top Level Requirements (TLR) document. By 1979 designs were no longer being numbered.

All basic directive numbers (those without letter suffixes) from 1 to 318 except 148 (no record) are accounted for in the sources. A few unusually significant directives with letter suffixes are also shown, but if a project number does not have a directive shown, it did not have one. Directives 6, 8, 176, and 300 were administrative. (Directive 300 introduced the TLR system as indicated above.)

This section is Copyright © Stephen S. Roberts 2022 or later as indicated.