In 1935, the United States Navy Naval Research Laboratory began studies and tests on low visibility ship camouflage. Research continued through World War II to (1) reduce visibility by painting vertical surfaces to harmonize with the horizon and horizontal surfaces to blend with the sea, or (2) confuse identity and course by painting obtrusive patterns on vertical surfaces. Some camouflage methods served both purposes. American captains were permitted less freedom of interpretation with these schemes (other than Measure 12 Modified) than their British Commonwealth counterparts applied to Admiralty camouflage schemes.Raven, 2012.
Early measures With the likelihood of the United States entering the war, and after experiments with various paint schemes conducted in association with the 1940 Fleet Problem (exercise), the Bureau of Ships (BuShips) directed in January 1941 that the peacetime color of overall #5 Standard Navy Gray, a light gloss shade with a linseed oil base, be replaced with matte Dark Gray, #5-D, a new paint formulation with a synthetic alkyd resin base. Rather than waste the large quantities of Standard Gray already in inventory and aboard ships, BuShips directed the issuance of a black tinting paste (5-BP) which when mixed in stated proportions with Standard Gray would yield a close approximation of 5-D, with issue of the new paint in pre-mixed form to follow. BuShips also issued Ship Camouflage Instructions (SHIPS-2), laying out 9 painting schemes to be used throughout the Navy. Rather than issue premixed quantities of the less-used new shades, Light Gray (5-L) and Ocean Gray (5-O), yards and supply depots were directed to issue an untinted base paint (5-U) together with a blue-black tinting material (5-TM) which when mixed according to instructions would turn 5-U into either Light or Ocean Gray.
Dull Black Dark Gray Ocean Gray (early) Light Gray (early)
The adoption of the new measures was very slow, however: as of late May the Navy's paint factories had yet to receive the ingredients needed for the new alkyd-based paints and only in late April had they received even the lampblack required for conversion paste 5-BP.
+ Early Measures (SHIPS-2, Ship Camouflage Instructions, Jan 1941) Name Description Image Measure 1Dark Gray (5-D) overall except for Light Gray (5-L) structures above the stack tops. Steel horizontal surfaces were Dark Gray; wooden decks were left bare, except for aircraft carriers which continued to use Mahogany Red stain on flight decks. Measure 1 was to be the default paint scheme for the entire Navy in the absence of other instructions.
Measure 1A was an experimental scheme in overall Sea Blue, later adopted as Measure 11.
Measure 1B was another experimental scheme using overall Sapphire Blue.
Measure 1C similarly used Navy Blue, later adopted as Measure 21. in Measure 1 during the attack on Pearl Harbor Measure 2 A graded system wherein the hull was painted in approximately equal bands of Dark Gray, Ocean Gray (5-O) and Light Gray, with all vertical superstructure surfaces painted Light Gray as well. Horizontal surfaces were as Measure 1, Dark Gray except for wooden decks. This measure was also widely used by the Royal Navy where it became known as the emergency scheme or Admiralty alternative scheme when there was insufficient time or where required pigments were unavailable to apply an Admiralty disruptive scheme. wearing Measure 2 Measure 3 Light Gray overallSumrall, 1973. similar to the Navy's interwar peacetime scheme (Light Gray was very similar to prewar Standard Navy Gray), and to the Royal Navy peacetime Mediterranean Fleet paint scheme. Horizontal surfaces as Measures 1 and 2. Measure 4 Destroyer Measure 4 was black overall, except for Light Gray above the stack tops. This was intended for destroyer night operations but it was found that even on very dark nights, black ships were more noticeable than gray ones. Measure 4 was also worn briefly by the aircraft carriers Ranger and Wasp. wearing Measure 4 Measure 5 A painted white bow wave used in combination with Measure 1, 2 or 3 to give the impression of high speed at all times. wearing Measure 5 (fake bow wave) with Measure 1. Measure 6 Cruiser Measure 6 made a or s resemble a , by painting a New Orleans silhouette on both sides: Light Gray on a Measure 1 ship, or Dark Gray on a Measure 2 or 3 ship. Measure 7 Similar to Measure 6, Cruiser Measure 7 made an resemble a . Measure 8 Similar to Measures 6 and 7, Cruiser Measure 8 made a Brooklyn or St. Louis-class cruiser resemble a two-funnel destroyer. This scheme was discontinued after causing station-keeping confusion among ships operating in formation. wearing a variant of Measure 8, 1943 Measure 9 Submarine Measure 9 was Dull Black (#82) overall and is still in use.
By the summer of 1941 it had become apparent that Dark Gray (5-D) was unacceptably visible under all conditions, and the "conversion" 5-D made from prewar #5 was also too glossy and prone to chipping and peeling; meanwhile Pacific Fleet experiments with new colors Sea Blue and Sapphire Blue were deemed successful. Accordingly, in July–August Dark Gray was discontinued and new paint formulas Sea Blue (5-S) and Haze Gray (5-H) were implemented, together with Deck Blue (20-B) for all horizontals, steel and wood alike. The tinting paste was altered to contain somewhat less black and more blue than before; this meant that Ocean Gray also became somewhat more bluish in cast at this time and all the 5-series paint colors now were categorized as Munsell 5 Purple-Blue. Until 1945 all USN "gray" and almost all "blue" shades were produced using this same blue-black tint (5-TMa), so that the paints represented different tones of what was effectively a single blue-gray hue.
Sea Blue Ocean Gray Haze Gray Deck Blue
In September, Measures 1 through 8 were abolished and four new schemes promulgated in a revised edition of SHIPS-2. On 19 July Measure 12 had been prescribed for the entire Atlantic Fleet, and on 13 September Measure 11 for the Pacific. However, there was a considerable time lag between the issuance of new instructions, and paint being manufactured and distributed and ships actually being repainted; at the time of the Pearl Harbor attack on December 7, 1941, most of the Pacific Fleet was still wearing dark gray Measure 1.
In November aircraft carriers began applying a dark blue-gray flight deck stain (#250) approximately the same color as Deck Blue, together with a stain approximately Ocean Gray for flight deck markings (#251). The Pacific Fleet's surface ships, less carriers, were ordered into Measure 11 on 16 December 1941. The order also substituted 5-N for 5-S Cincpac File No.A2-11/FF12(2) S19/(50) Serial 02050
+ Revised Prewar Measures (SHIPS-2 Rev. 1, Sept 1941) Name Description Image Measure 11 Sea Blue (5-S) overall, with horizontal surfaces (including wooden portions) painted Deck Blue (20-B). All visible canvas boat covers, tarpaulins and windscreens to be dyed in a color to match Deck Blue. It was used in the Pacific and Mediterranean for concealment from aircraft. Royal Navy submarines operating in the Mediterranean used a similar scheme. During the Battle of the Coral Sea and the Battle of Midway, ships wearing Measure 11 came under attack less often than ships wearing Measure 12. in summer 1941 wearing experimental Measure 1B (note the light gray 5-L on the mast above the funnel and director), a precursor of Measure 11. Measure 12Measure 12 (Modified) Sea Blue on the hull up to the main deck (hangar deck on aircraft carriers), Ocean Gray from main deck level to the top of the superstructure masses, and Haze Gray (5-H) for masts and other vertical projections above superstructure level. Horizontal surfaces painted Deck Blue. Canvas dyed blue. Sea Blue was later darkened to Navy Blue (Measure 12A). It was found to be ineffective against aerial observation during the early carrier aircraft battles of Coral Sea and Midway, so all-blue Measure 11 and its replacement Measure 21 became preferred in the Pacific.
In Measure 12 (Modified), irregular patches or splotches were added to break up the ship's profile: Haze Gray splotches on Sea Blue (later Navy Blue) and vice versa, and Sea Blue (later Navy Blue) splotches on Ocean Gray. "These splotches should be obtained by extending the Navy Blue paint into the designated Ocean Gray paint area and vice versa. They should be about 1/3 the area of a rectangle 12 feet high by 20 feet long." There were no specific instructions on the positioning or shape of the splotches, which were left up to individual captains, yards or maintenance facilities, and the recommended size was frequently disregarded, so that no two ships looked alike. Measure 12 (Mod) was used extensively in both fleets during 1942. Unfortunately the splotches in most cases were too small to break up the ship's outline effectively, and at any distance resolved into simple gray. wearing measure 12
wearing Measure 12 (Modified)
wearing measure 12 (Modified).Alabamas 1942 paint colors were Ocean Gray with either Pale Gray or White in broad diagonal stripes, and may have been a unique scheme devised for her deployment to the Arctic rather than an actual Measure 12m. Measure 13 Haze Gray (5-H) overall, with horizontal surfaces Deck Blue. This was the least used solid color measure during World War II. "Low visibility to surface observers in hazy or foggy weather especially when it is accompanied with periods of weak sunlight... Useful in submarine infested areas, where periscopic observers will see a vessel entirely against a sky background. High visibility under searchlight, and down-moon at close ranges. Very low visibility on moonless nights and at twilight"
This was found to provide reasonable protection in the widest range of conditions, and became a standard paint scheme after the war under assumed conditions of radar observation, with Deck Gray substituted for Deck Blue. Measure 14 Ocean Gray overall. Used on many small craft, including minesweepers, PTs, SCs, PCS, and some Coast Guard vessels as well as several escort carriers (CVEs) throughout 1942, 1943, and 1944. "Useful for Protection against Submarine attack, where aerial observation is a lesser factor... In Atlantic or Pacific Coastal waters where weather is generally sunny, visibility is high, and bright moonlight is common at night."
Asiatic Fleet: The Asiatic Fleet, based in distant Manila, was unable to obtain the new paint colors and so in November painted its ships overall in a color procured from local sources midway between Sea Blue and Ocean Gray, dubbed "Cavite Blue."
Improved measures from combat experience Thayer Blue + Wartime Measures (Mid-1942) Name Description Image Measure 15 An experimental dazzle pattern developed directly from British First Admiralty Disruptive Type. Used in late 1942 on at least three vessels, the battleship , the destroyer , and the oiler , in Navy Blue, Ocean Gray, Haze Gray and (Hobson only) White