# Ship Characteristics Board

The Ship Characteristics Board was a unit of the United States Navy.
The purpose of the Ship Characteristics Board was to coordinate the creation of 'ship characteristics' that are essential to the design of naval combatants and auxiliaries. Coordination was required because the operators and the designers of ships had different interests, perceptions, concepts, and constraints: as summarized by the naval historian Norman Friedman, "How to achieve the best possible compromise among competing bureaus has been one of the great dilemmas of 20th-century U.S. naval administration."
This list of SCB projects is a useful exposition of the U.S. Navy's shipbuilding priorities in the first half of the Cold War.

## History

The Ship Characteristics Board was founded in 1945 under the Office of the Chief of Naval Operations / OpNav. It was created after the body previously responsible for coordinating ships characteristics, the General Board, had been seen as ineffective in a series of earlier Navy bureau miscoordinations. The SCB would adjudicate between operational requirements set by the ship operators (the fleets and other operational forces) and the technological and fiscal constraints imposed on the ship designers (the Bureau of Ships / BuShips and the Bureau of Ordnance / BuOrd).
   The SCB had nowhere near the same stature as its predecessor [the General Board], since in effect it was separated from the policy- and strategy-planning process. It was far more concerned with the details of design, and included representatives of all the bureaus, who had equal votes. Participants in SCB meetings recall cases in which the Bureau of Medicine and Surgery cast the decisive vote on weapons systems choices. From the surviving records it is not entirely clear who within OpNav worked up the lists of projects on which the SCB worked, at least at first. For a time that was both very important, given the poverty of the [post-World War Two] shipbuilding program and the lack of any integrated U.S. concept of future warfare.
The SCB assigned numbers to its projects beginning in 1946. Not all projects would result in the construction of ships: some projects would remain conceptual only, or would be superseded by later projects.
In 1966 the successors to BuShips and BuOrd (NAVSHIPS and NAVORD) were moved to report to OpNav. The SCB role as an adjudicator became less relevant. During the development of the Oliver Hazard Perry class frigates it was renamed the Ship Acquisition and Improvement Board (SAIB). In the 1980s it was revived as the Ship Characteristics Improvement Board (SCIB), but without its former authority.

### USS Thresher loss

A decision by the SCB likely contributed to the 1963 loss of the nuclear submarine Thresher. The SCB had ordered BuShips to study increasing the test depth for future submarines from 700 to 1,600 feet, and this increase was approved after November 1956. Thresher's components were too far along in design to accommodate this change, but it was decided that they could be modified to enable a test depth of 1,300 feet. The irony is that the SCB's motives for this change were to enhance safety: not only to support greater combat survivability, but also out of a concern that the increased speed of nuclear submarines could cause them to inadvertently exceed the more shallow test depths while maneuvering.

## List of SCB projects

Review of the following lists of SCB projects will show:
* SCB projects which are 'follow on' to earlier projects may be given a new number, or may reuse an earlier number with an appended letter. For example, a project to develop a new Landing Craft Utility (LCU) was begun in 1946 as SCB 25, follow on LCU projects include SCB 25A (unknown date), SCB 149 (August 1954), and SCB 149B (March 1962). Note the eight-year gap between SCB 149 and SCB 149B.
* The start date of an SCB project can be several years before it became a budget line item or an actual ship construction. SCB 157 began in July 1955 as a study for a new amphibious assault helicopter carrier, but a resultant ship (the future Iwo Jima) was not laid down until 2 April 1959. An even more extreme example is SCB 123, which began in 1954, but which saw last ship reconstruction delayed until 1966.
* Close examination of SCB projects will occasionally demonstrate that ship design history is more complicated than first appearances show. For example, the George Washington class of fleet ballistic missile submarines was the first such class to be launched. However, the history of SCB 180 shows that the Ethan Allen class was the first to be designed, and the George Washington class was a subsequent design made for a quickly implemented mobilization effort.
* The budgetary pressures of the Vietnam War, including war driven inflation, are demonstrated in the cancellation of SCB projects 003.68 and 101.68, and the partial cancellation of SCB 002 (the age of the ships was also a factor).
All ship hull classification symbols shown (CLK, SS, DL, CVA, DE, etc.) are the symbols in use at the conception of the project, rather than when construction started. Explanations of these symbols are usually to be found in the linked articles on each ship or class.

### Sequential numbering of SCB projects

SCB projects began in numeric sequence in 1946, and were originally listed in descending priority (the Norfolk cruiser/destroyer leader having top priority, the Tang submarines as second priority, etc.), but such prioritization was eventually dropped. Several of the early projects actually began in 1945 - for example, the Mitscher-class destroyer (which in 1946 was assigned the project number SCB 5) was the ship design that on paper out-performed the projected CL-154 class light cruiser design and led to that cruiser's cancellation in September 1945.
| SCB # | Start date | Description |
| SCB 1 | 1946 | Norfolk CLK |
| SCB 2 | 1946 | Tang class SS |
| SCB 2A | | Grayback SS original design (see SCB 161) |
| SCB 3 | 1946 | Closed cycle engine SSX concept |
| SCB 4 | 1946 | CVA concept, merged into SCB 6 by Jun 1946 |
| SCB 5 | 1946 | Mitscher class DL |
| SCB 6 | 1946 | Strategic CVA (aircraft carrier) concept |
| SCB 6A | | United States class CVA, cancelled 23 Apr 1949 |
| SCB 7 | 1946 | 30 kt DE concept |
| SCB 7A | | Fletcher class DD ASW mobilization concept |
| SCB 8 | 1946 | CVE ASW concept, became SCB 43 |
| SCB 9 | 1946 | 15 kt LST concept |
| SCB 9A | | Terrebonne Parish class LST |
| SCB 10 | 1946 | AKA Arctic conversion concept |
| SCB 11 | 1946 | CLI Cruiser-icebreaker Arctic picket concept |
| SCB 11A | | Glacier AGB |
| SCB 12 | 1946 | MIGRAINE II SSR conversions: Burrfish, Requin, Spinax and Tigrone |
| SCB 12A | | MIGRAINE III SSR conversions: Pompon, Rasher, Raton, Ray, Redfin, and Rock |
| SCB 13 | 1946 | Northampton CLC |
| SCB 14 | 1946 | Paul Revere class APA |
| SCB 14E | | APA conversion of SS Monterey and SS Mariposa |
| SCB 15 | 1946 | Tulare class AKA |
| SCB 16 | 1946 | Fast AGC concept |
| SCB 17 | 1946 | Fast LSD concept |
| SCB 18 | 1946 | LSM Underwater Object Locator conversion concept |
| SCB 19 | 1946 (Dec 1945) | Kentucky BB anti-air concept |
| SCB 20 | 1946 | Steel hulled PT concept |
| SCB 21 | 1946 | Radiological salvage vessel concept, later ATR rescue tug concept |
| SCB 22 | 1946 | Fast AOR concept, led to commissioning of ex-war prize Conecuh as a test |
| SCB 22A | | YAG conversion concept |
| SCB 23 | 1946 | Fast AK concept |
| SCB 24 | 1946 | Midget SS concept |
| SCB 25 | 1946 | LCU 1466 |
| SCB 25A | | LCU 1608 |
| SCB 26 | 1946 | Hawaii CB aircraft carrier conversion concept |
| SCB 26A | 1948 | Hawaii CB missile conversion concept |
| SCB 27 | 1946 | Oriskany CVA jet aircraft conversion |
| SCB 27B | | Essex class CVA partial conversion, canceled |
| SCB 27A | | Essex class CVA modification: 8 ships |
| SCB 27C | | Essex class CVA modification: 6 ships |
| SCB 28 | 1946 | Tunny SSG conversion |
| SCB 29 | 1946 | LSD Arctic conversions: Gunston Hall and Lindenwald |
| SCB 30 | 1946 | ASSP conversions: Perch and Sealion |
| SCB 31 | 1946 | Barbero ASSA conversion |
| SCB 32 | 1946 | Fast LST concept |
| SCB 33 | 1946 | SSG (guided missile submarine) concept |
| SCB 34 | 1946 | SSV F2Y seaplane carrier submarine concept |
| SCB 35 | Dec 1946 | Barracuda class SSK |
| SCB 36 | 1948 | New LCS(L) concept, merged into SCB 37 |
| SCB 37 | 1948 | Carronade LSM(R) |
| SCB 38 | | Colorado BB radio control target conversion concept |
| SCB 39 | | Guavina SSO conversion |
| SCB 40 | | SSE (submarine ammunition carrier) concept |
| SCB 41 | | CVL ASW conversion, became SCB 54 |
| SCB 42 | | LSD to AV conversion concept |
| SCB 43 | | CVE ASW concepts, cancelled Apr 1954 |
| SCB 44 | | Aviation stores issue ship (AVS) concept |
| SCB 45 | | AMS concept |
| SCB 45A | | Agile class MSO and Acme class MSO |
| SCB 45B | | Ability class MSO |
| SCB 46 | | DER conversions: 6 ships |
| SCB 46A | | DER conversions: Vandivier and Wagner |
| SCB 46B | | DER conversions: 28 ships |
| SCB 47 | | GUPPY II SS conversions |
| SCB 47A | | GUPPY IA SS conversions |
| SCB 47B | | Fleet snorkel SS conversions |
| SCB 47C | | GUPPY IIA SS conversions |
| SCB 48 | | Boston class CAG Terrier missile conversions |
| SCB 49 | | Altair class AKS conversion |
| SCB 50 | | AOR conversion concept |
| SCB 51 | | DE or PCE concept, became SCB 72 |
| SCB 52 | | Submersible barge concept for launching V-2 rockets |
| SCB 53 | | DDE conversion |
| SCB 54 | | CVL ASW conversion |
| SCB 56 | 1949 | Albacore AGSS Phase I |
| SCB 57 | | Denebola-class AF conversion: 4 ships |
| SCB 58 | 1949 | Grouper SSK conversion |
| SCB 59 | | Cylindrical Countermeasures (XMAP) minesweeping device |
| SCB 60 | | LVT modernization |
| SCB 60A | | LVT(A)5 modernization |
| SCB 60B | | LVT(3) modernization |
| SCB 61 | | Yard and district craft characteristics |
| SCB 61A | | YR characteristics |
| SCB 61B | | YON characteristics |
| SCB 61C | | YFN characteristics |
| SCB 61D | | YRB characteristics, became SCB 61N |
| SCB 61E | | YC characteristics |
| SCB 61F | | YFB characteristics |
| SCB 61G | | YCF characteristics |
| SCB 61H | | YOGN characteristics |
| SCB 61J | | YRBM characteristics |
| SCB 61K | | YDT characteristics |
| SCB 61L | | YFR characteristics |
| SCB 61M | | YNG characteristics |
| SCB 61N | | YRB characteristics |
| SCB 61P | | YTN characteristics |
| SCB 61Q | | YOG characteristics for JP-5 |
| SCB 61R | | YTM characteristics with cycloidal propulsion |
| SCB 62 | | Minesweeping boat (MSB) |
| SCB 63 | | Tweedy DE ASW upgrade |
| SCB 63A | | Lewis DE ASW upgrade |
| SCB 64 | Mar 1950 | Nautilus SSN |
| SCB 64A | Mar 1950 | Seawolf SSN |
| SCB 65 | | X-1 midget SS |
| SCB 66 | | SSM (submarine minelayer) conversion concept, cancelled 1 Oct 1952 |
| SCB 67 | 1950 | Closed cycle engine SSX concept |
| SCB 67A | | Closed cycle engine SSX concept, cancelled 26 Oct 1953 |
| SCB 68 | Apr 1950 | Mackerel class SST |
| SCB 69 | | Adjutant class MSC |
| SCB 69A | | MSC concept |
| SCB 70 | | AD mobilization conversion concept |
| SCB 71 | | AP mobilization conversion from SS United States concept |
| SCB 72 | Oct 1950 | Dealey class DE |
| SCB 73 | | ACMU conversions |
| SCB 74 | | Various anti-air upgrades (e.g. Bofors 40 mm guns replaced with 3"/50 caliber guns) |
| SCB 74A | | Fletcher class DD anti-air upgrades: 40 ships |
| SCB 74B | | Light Cruisers anti-air upgrades |
| SCB 74C | | Heavy Cruisers anti-air upgrades |
| SCB 74D | | Juneau anti-air upgrade |
| SCB 74E | | Iowa class BB anti-air upgrade concept |
| SCB 75 | Nov 1950 | Thomaston class LSD |
| SCB 76 | | Mobilization DD experiment concept |
| SCB 77 | Jul 1951 | New AKA concept |
| SCB 77A | Nov 1952 | New AKA with ro-ro capability concept |
| SCB 78 | | Paul Revere APA |
| SCB 78A | | Francis Marion APA |
| SCB 79 | | DDR (destroyer radar picket) conversions |
| SCB 80 | | Forrestal class CVA |
| SCB 81 | | Technical stores issue ship (AKST) concept |
| SCB 82 | | Neosho class AO |
| SCB 83 | | Hawaii CBC conversion concept |
| SCB 84 | | Sailfish class SSR |
| SCB 85 | Feb 1951 | Forrest Sherman class DD |
| SCB 85A | | Forrest Sherman class (Hull sub-class) DD |
| SCB 86 | | AK reactivation: Altair, Antares, Alcor and Betelgeuse |
| SCB 87 | | AVP concept |
| SCB 88 | | Gearing class DD completion concept |
| SCB 89 | May 1951 | 180-foot PC concept |
| SCB 90 | May 1951 | 290-foot PCE concept |
| SCB 91 | | DM concept |
| SCB 92 | | AGC concept |
| SCB 93 | | AKA concept, canceled 4 Jan 1952 |
| SCB 94 | Nov 1951 | LCM(6) |
| SCB 95 | | LCM(8) |
| SCB 96 | | LCVP |
| SCB 97 | | Rigel class AF |
| SCB 98 | | ATR concept |
| SCB 99 | | AE mobilization concept |
| SCB 100 | | AF mobilization concept |
| SCB 101 | | AR mobilization concept |
| SCB 102 | | AVS mobilization concept |
| SCB 103 | | ARH mobilization concept |
| SCB 104 | | AK mobilization concept |
| SCB 105 | | AK mobilization concept |
| SCB 106 | | AKS mobilization concept |
| SCB 107 | | AD mobilization concept |
| SCB 108 | | AKST mobilization concept, canceled 26 Mar 1952 |
| SCB 109 | | Bittern ACMU |
| SCB 110 | | Midway CVA and Franklin D Roosevelt CVA modernizations |
| SCB 110A | | Coral Sea CVA modernization |
| SCB 111 | | AVP concept |
| SCB 112 | | AO Arctic concept |
| SCB 113 | | LST Arctic concept |
| SCB 114 | | Suribachi class AE |
| SCB 115 | | AVS (aviation stores ship) |
| SCB 116 | | Darter SS (see also SCB 124) |
| SCB 117 | | DE gas turbine engine, canceled 1955 |
| SCB 118 | | Barbero SSG conversion |
| SCB 119 | Nov 1953 | De Soto County class LST |
| SCB 120 | | AP mobilization conversion of passenger liners |
| SCB 121 | | Skate class SSN |
| SCB 122 | May 1954 | Thetis Bay CVHA conversion |
| SCB 123 | | MCS conversions: Catskill, Ozark, Osage, Saugus, and Monitor (last 3 cancelled) |
| SCB 124 | | Improved SCB 116: Growler SS original design (see SCB 161) |
| SCB 125 | | Essex class CVA modification: 13 ships |
| SCB 125A | | Oriskany CVA modification |
| SCB 126 | | Guardian class AGR conversion |
| SCB 127 | | Kitty Hawk class CVA, preliminary design |
| SCB 127A | | Kitty Hawk class CVA: Kitty Hawk and Constellation |
| SCB 127B | | Kitty Hawk class CVA follow on: America |
| SCB 127C | | Kitty Hawk class CVA follow on: John F. Kennedy |
| SCB 128 | | LCPL |
| SCB 128A | | LCPL |
| SCB 128B | | LCPL |
| SCB 129 | May 1954 | Farragut class DL |
| SCB 130 | | Fletcher class DDC (destroyer corvette) conversion concept |
| SCB 131 | Jun 1954 | Claude Jones class DE |
| SCB 132 | | Triton SSRN |
| SCB 133 | | ASRD concept |
| SCB 134 | | Albemarle AV P6M seaplane modification |
| SCB 135 | | Gyatt DDG conversion |
| SCB 136 | | Cove MSI (inshore minesweeper) |
| SCB 137 | | Halibut SSG original design with diesel-electric propulsion |
| SCB 137A | | Halibut SSGN final design with nuclear propulsion |
| SCB 137B | | SSGN concept with twice the missile load as Halibut |
| SCB 138 | | ARC conversions: Aeolus and Thor |
| SCB 139 | | YP-654 class |
| SCB 140 | | Galveston class CLG Talos missile conversion |
| SCB 140A | | Galveston class CLG Talos missile flagship conversions: Little Rock and Oklahoma City |
| SCB 141 | 1954 | New LCM(3) concept |
| SCB 142 | | Farragut class (Coontz sub-class) DLG |
| SCB 143 | | Admirable class AM and Auk class AM conversion to PCE concepts |
| SCB 144 | | Essex class CVS FRAM upgrade |
| SCB 145 | | CVL angled flight deck concept |
| SCB 146 | | Providence class CLG Terrier missile conversion: Topeka |
| SCB 146A | | Providence class CLG Terrier missile flagship conversions: Providence and Springfield |
| SCB 147 | | YTB-752 class harbor tug |
| SCB 147A | | YTB-760 class |
| SCB 148 | | unknown project |
| SCB 149 | Aug 1954 | LCU 1620 |
| SCB 149B | Mar 1962 | LCU 1625 |
| SCB 150 | | Barbel class SS |
| SCB 151 | | Currituck AV P6M seaplane modification, cancelled 21 Aug 1959 after 52 days of construction |
| SCB 152 | Jul 1955 | Fast catamaran LST with causeway concept |
| SCB 153 | | Alternative CV concept, cancelled 14 Sep 1955, influenced SCB 127A and SCB 160 |
| SCB 154 | | Skipjack class SSN |
| SCB 155 | Aug 1955 | Charles F. Adams class DDG |
| SCB 156 | | AF conversion, canceled Nov 1955 |
| SCB 157 | Jul 1955 | Iwo Jima class LPH |
| SCB 158 | | CN (nuclear cruiser) concept |
| SCB 159 | | Block Island LPH conversion, cancelled 1958 |
| SCB 160 | | Enterprise CVAN |
| SCB 161 | | Grayback and Growler SSG final design (see SCB 2A and 124) |
| SCB 162 | Apr 1956 | LCM hydrofoil concept |
| SCB 163 | | CN concept |
| SCB 165 | | CN concept |
| SCB 166 | | Original SSGN design of Thresher / Permit class |
| SCB 166A | | Improved SSGN design of Thresher / Permit class, changed to SSN under SCB 188 |
| SCB 167 | | CN concept |
| SCB 168 | | CN concept |
| SCB 169 | | Long Beach CGN |
| SCB 170 | | Guavina AOSS conversion |
| SCB 172 | | Leahy class DLG |
| SCB 172A | Jun 1960 | Belknap class DLG |
| SCB 173 | | Albany class CG conversions |
| SCB 173A | | Baltimore class Polaris missile conversion concept |
| SCB 174 | | Des Moines class CG conversion concept |
| SCB 176 | | Commencement Bay class AV P6M seaplane conversion concept, cancelled 21 Aug 1959 |
| SCB 177 | | Tallahatchie County AVB conversion |
| SCB 178 | | Tullibee SSN |
| SCB 179 | | Victory ship conversion to survey ship concept |
| SCB 180 | | Ethan Allen class SSBN |
| SCB 180A | | George Washington class SSBN |
| SCB 182 | 1957 | Albacore AGSS Phase III |
| SCB 182A | 1959 | Albacore AGSS Phase IV |
| SCB 183 | 1956 | PCS concept |
| SCB 184 | 1956 | SC concept |
| SCB 185 | | Conrad class AGOR |
| SCB 187 | Jan 1957 | Raleigh class LPD |
| SCB 187A | | Raleigh class LPD with flagship facilities: La Salle |
| SCB 187B | | Austin class LPD |
| SCB 188 | | Thresher / Permit class SSN |
| SCB 188A | | Sturgeon class SSN |
| SCB 188M | | Lengthened Permit class SSNs: Flasher, Greenling, and Gato |
| SCB 189 | | Bainbridge DLGN |
| SCB 190 | | Proteus AS modernization |
| SCB 191 | | Terror Middle East force flagship conversion concept |
| SCB 192 | | Oxford class AGTR conversion |
| SCB 194 | | Hunley class AS |
| SCB 196 | | Sacramento class AOE |
| SCB 198 | | Glover AGFF conversion |
| SCB 199 | | Bronstein class DE |
| SCB 199A | | Garcia class DE |
| SCB 199B | | Brooke class DE |
| SCB 199C | | Knox class DE |
| SCB 202 | Apr 1958 | High Point PCH |
| SCB 203 | | CVAN concept, became SCB 211 |
| SCB 205 | | AGMs for range instrumentation |
| SCB 206 | Nov 1958 | Gearing class DD FRAM I |
| SCB 207 | | Dolphin AGSS |
| SCB 208 | | Mars class AFS |
| SCB 211 | | CVAN concept |
| SCB 211A | | CVAN concept, cancelled in favor of SCB 127C |
| SCB 212 | | Austere DDG (guided missile destroyer) concept, influenced SCB 172A |
| SCB 214 | | Serrano AGS conversion |
| SCB 215 | | Gilbert Islands AGMR conversion |
| SCB 216 | | Lafayette class SSBN |
| SCB 216A | | Benjamin Franklin class SSBN |
| SCB 216 Mod 3 | | James Madison class SSBN |
| SCB 218 | Aug 1960 | Albemarle ASGL satellite launch concept |
| SCB 219 | 1960 | Plainview AGEH |
| SCB 220 | | Nasty class PTF |
| SCB 221 | Aug 1960 | 52 foot UDT reconnaissance boat |
| SCB 222 | | Tuxtrun DLGN |
| SCB 223 | | GUPPY III SS FRAM |
| SCB 224 | | Cimarron class AO jumbo conversion: Mispillion sub-class |
| SCB 225 | | Kingsport AG conversion |
| SCB 226 | | Silas Bent class AGS |
| SCB 227 | Mar 1961 | Typhon DLGN concept |
| SCB 228 | | Wright CC conversion |
| SCB 229 | | Asheville class PGM |
| SCB 231 | | NECPA CC concept |
| SCB 232 | | Suribachi class AE modernization |
| SCB 233 | | Norton Sound AVM modification |
| SCB 234 | | Victory ship AS (submarine tender) conversion |
| SCB 236 | | Sea Lift LSV |
| SCB 238 | | Simon Lake class AS |
| SCB 239 | | Seahawk DD concept |
| SCB 240 | | Forrest Sherman class DDG Tartar missile conversion: 4 ships |
| SCB 241 | | Mitscher class DDG Tartar missile conversion: 2 ships |
| SCB 242 | | Sailfish SS FRAM II refit |
| SCB 244 | | Samuel Gompers class AD |
| SCB 245 | | Narwhal SSN |
| SCB 247 | Jun 1962 | Newport class LST |
| SCB 248 | Nov 1962 | Blue Ridge class LCC |
| SCB 250 | | CVAN concept, canceled in favor of SCB 127C |
| SCB 251 | | Forrest Sherman class (Barry sub-class) DD modernization with ASROC |
| SCB 252 | Jan 1964 | Flagstaff PGH and Tucumari PGH |

### Block numbering of SCB projects

By 1965 the numeric sequence was abandoned and SCB projects were organized by block numbers which arranged projects by ship types (valid until the 1975 ship reclassification), and a two digit suffix denoting the fiscal year of the construction phase of the project. This suffix is not the start date of the project as a concept: SCB 400.65 actually began in November 1962, not in 1965, and SCB 409.68 actually began in February 1965, not in 1968. The existence of successive suffixes also does not necessarily mean that the design of ships of a class in any way changed, such suffixes are listed here for historical note only.
In effect, this new numbering scheme changed the focus of the SCB from design and development to procurement and budget compliance. As a result, concept-only designs would largely disappear from the historical record.
| 1965-1975 SCB block # | Ship type |
| 001-099 | Cruisers |
| 100-199 | Carriers |
| 200-299 | Destroyers/Frigates |
| _ 200-219 | Destroyer Escorts |
| _ 220-239 | Destroyers |
| _ 240-259 | Frigates (past Destroyer Leaders) |
| _ 260-280 | Patrol Frigates |
| 300-399 | Submarines |
| 400-499 | Amphibious |
| 500-599 | Mine Warfare |
| 600-699 | Patrol |
| 700-799 | Auxiliaries |
| 800-899 | Service Craft |
| 900-999 | Special Purpose |
| SCB # | Start date | Description | Notes |
| SCB 002 | | Albany class CG AAW modernization (Chicago partially only, Columbus cancelled) | |
| SCB 003.68 | | Boston class CAG AAW modernization, cancelled | |
| SCB 100.68 | | CVS ASW concept, became SCB 100.71 | |
| SCB 100.71 | | CVS ASW concept | |
| SCB 101.66 | | Midway CVA modernization | |
| SCB 101.68 | | Franklin D. Roosevelt CVA modernization, cancelled | |
| SCB 102.67 | | Nimitz class CVN | |
| SCB 103.68 | | Franklin D. Roosevelt CVA austere refit | |
| SCB 200.65 | | Knox class DE (former SCB 199C) | |
| SCB 222.66 | | Forrest Sherman class DD ASW modernization (former SCB 251) | ibid |
| SCB 223.67 | | DDG | |
| SCB 224 | | Spruance class DD | |
| SCB 226 | | Ticonderoga class DDG | |
| SCB 240.65 | Mar 1961 | Typhon DLGN concept (former SCB 227) | ibid |
| SCB 241.66 | | California class DLGN | |
| SCB 243.66 | | Farragut class DLG upgrade | |
| SCB 244.66 | | Leahy class DLG upgrade | |
| SCB 246 | | Virginia class DLGN | |
| SCB 261 | | Oliver Hazard Perry class FFG | |
| SCB 300 | | Sturgeon-class SSN | |
| SCB 301 | | NR-1 | |
| SCB 302 | | Glenard P. Lipscomb SSN | |
| SCB 303 | | Los Angeles class SSN | |
| SCB 304 | | Ohio class SSBN | |
| SCB 350 | | Grayback LPSS conversion | |
| SCB 351 | | Halibut SSN conversion | |
| SCB 353 | | James Madison and Benjamin Franklin classes SSBN Poseidon C-3 missile conversion | |
| SCB 355 | | Lafayette and Benjamin Franklin classes SSBN Poseidon C-3 conversion | |
| SCB 400.65 | Nov 1962 | Blue Ridge class LCC (former SCB 248) | ibid |
| SCB 401.65 | Jul 1955 | New Orleans LPH (former SCB 157) | ibid, |
| SCB 402.65 | | Austin class LPD (former SCB 187B) | ibid |
| SCB 403.65 | | Charleston class AKA | |
| SCB 404.65 | | Anchorage class LSD, lead ship only | |
| SCB 404.66 | | Anchorage class LSD, follow on ships | |
| SCB 405.65 | Jun 1962 | Newport class LST, lead ship only (former SCB 247) | ibid, |
| SCB 405.66 | Jun 1962 | Newport class LST: follow on ships (former SCB 247) | ibid, |
| SCB 406.65 | | LCU 1627 | |
| SCB 409.68 | Feb 1965 | Tawara class LHA | |
| SCB 500.66 | | Liberty ship MSS conversion concept | |
| SCB 501.66 | | MSO (ocean minesweeper) concept | |
| SCB 502 | | MSO modernization | |
| SCB 600 | | Asheville class PGM (former SCB 229) | ibid |
| SCB 602 | | Pegasus class PHM | |
| SCB 700.66 | | Samuel Gompers class follow on: AD-39, cancelled (former SCB 244) | ibid, |
| SCB 701 | | AVB (aviation logistics support ship) | |
| SCB 702.65 | | L Y Spear class AS | |
| SCB 703.65 | | Kilauea class AE | |
| SCB 704 | | AGB (icebreaker) | |
| SCB 705 | | Mars class AFS (former SCB 208) | ibid |
| SCB 706 | | Cimarron class AO jumbo conversion: Ashtabula sub-class | |
| SCB 707 | | Wichita class AOR | |
| SCB 708.65 | | Chauvenet class AGS | ibid |
| SCB 709 | | Serrano AGS conversion (former SCB 214) | ibid |
| SCB 710 | | Melville class AGOR | |
| SCB 711.65 | | Sacramento class AOE (former SCB 196) | ibid, |
| SCB 713 | | Mission Buenaventura class AO jumbo conversion | |
| SCB 714 | | AS (submarine tender) | |
| SCB 719 | | Edenton class ATS | |
| SCB 720 | | Fast Deployment Logistic Ship FDL | |
| SCB 721 | | Pigeon class ASR | |
| SCB 723 | | Chauvenet AGS | |
| SCB 726 | | Hayes class AGOR (former SCB 226) | ibid |
| SCB 728 | | Wyman AGS | |
| SCB 734 | | Gyre class AGOR | |
| SCB 737 | | Emory S Land class AS | |
| SCB 739 | | Cimarron class AO | |
| SCB 744 | | Powhatan class ATF | |
| SCB 800.65 | | YP-654 class | |
| SCB 900.65 | | Iowa class BB ASGL satellite launch concept | |

## CIP

The SCB also had a list of projects called Class Improvement Projects. These were usually changes of a lesser scope or risk than SCB projects; many were contingency plans to refurbish reserve ships had it been necessary to reactivate them. No list of CIP numbers is available.