The basics are:
1919-1934: Wood and fabric airplanes. Overall Olive Drab (#9?), glossy when applied, weathered to dull.
May 23, 1934 to March, 1938,
Light Blue #23: Fuselage, Spinner, Wheels, Landing Gear.
Yellow #4: Wings, Control Surfaces, Horizontal and Vertical Stabalizers
Aluminum paint or polished metal for non-grab items like Pitot tubes, venturis, antennae, etc.
Maroon #18 for propeller blades when a flat finish is required.
Black # for floats or hulls, below the waterline.
New build airplanes from 1937, all from March, 1938.
Metal surfaces: Polished aluminum.
Non-metalic surfaces: Aluminum dope
Flat Bronze Green #8 for anti-glare panels on fuselage, engine nacelles, etc.
Switching from painted to Natural Metal surfaces was primarily an economy move- it was cheaper to maintain an airplane with a polished exterior than one that was painted. Clearly the cost of labor was small to non-existant!
October 16, 1940 to 1943 when bare metal was again specified:
(Dark) Olive Drab (No. 31, later No 41, still later ANA 613) over
Neutral Gray. (No. 32, later, No. 43, still later ANA 603 Sea Gray)
Two other colors,Medium Green (#30 Dark Green? later #42) and
Sand (#26, later #49, still later ANA 616)
were authorized for areas where Olive Drab wasn’t suitable, in the opinion of the local commander.
Azure Blue, ANA 609, was authorized for undersides in the North African theatre.
Glossy Black, #33, later #33 and then ANA ???, was specified for night operations.
Clearly there were a number of paint code and standard systems, with four different numbers for the popular (Dark) Olive Drab Olive Drab! No. 9 in the post-WWI era,, Dark Olive Drab #31, then Olive Drab #41 for a time and then Olive Drab ANA 613. Each of these is a different, actual, color, and the war-time formulations of 613 (and possibly 41) faded quickly, to more than one, distinctive, color.
As of March, 1942, Medium Green was also used to make splotches on the leading and trailing edges of Olive Drab airplanes, applied to the wings, vertical and horizontal stabalizers and control surfaces, to break up the outline. This isn’t always visible in contemporary black and white photos of new-ish planes, but can be clearly seen when the O.D. has weathered.
In the Pacific theatre, B-17 squadrons used Dark Green #30 and Sand #26, for example, on the aircraft which flew from Midway Island in June, 1942.
Later in the war, no camouflage was required, and natural metal, aluminum dope on fabric surfaces and aluminum laquer in the case of the ultra-smooth P-51 “Laminar” wings, were the standards. Flat black and olive drab were used for anti-glare panels ahead of pilot’s windscreens or in other places the pilot could see their own airplane.
Bronze Green and Dull Dark Green were codified in the middle of the war, 1942-43, for interiors, in addition to the ANA 611 color created as a target for zinc chromate primer to be tinted to with black (and possibly aluminum paste) for UV resistance. A/N 611 paint wasn’t made, as such, primer was tinted by the airframe builders to match the standard to a greater or lesser degree.
Bell Aircraft used a Bronze Green of their own specification throughout the war. Grumman used a light gray of their own specification, similarly.
Airplanes built for the British, French or Dutch under contract typically had something approaching their intended customer’s color scheme, but this varied by manufacturer from very good (British colors on P-40s) to not quite right (British colors on P-39s). When foriegn orders were taken over after Pearl Harbor, or diverted later in the war, the planes that appeared in US service might not have matched any specific technical orders. There was, after all, a war on.
Natural metal was the order of the day in the immediate post-war period and during the Korean War.
The natural metal finish always included aluminum dope on cloth covered surfaces (B-29s had cloth covered control surfaces…) and aluminum paint on magnesium parts, such as a great deal of the B-36s skin. What F-51Ds left in service, still had puttied, sanded and painted wings for “laminar flow”, just as they had during the “natural metal’ years in WWII. Some B-29s, delivered in natural metal, had glossy black undersides painted on when the 20th AF switched from daylight precision bombing to area fire-bombing at night. B-29s operating over Korea had or aquired glossy black undersides for night operations after MiG-15s made daylight bombing unsustainable.
“Arctic” Red”, a pigment selected for its resistance to fading, was applied to wingtips and tail surfaces of bombers, fighters and transports operating at high lattitudes in the 1940s and 50s. Sometimes it is neatly sprayed, sometimes it appears to have been applied with a mop. Flying above Alaska, the Northern Territories of Canada, Greenland, etc, was a dangerous business even without the reconnisance cat-and-mouse games played over the Pole near the Soviet border. Some US flights were attacked and shot-down over international waters. Some US flights went into Soviet territory.
USAF 1950s. “Natural metal” is mostly just that- polished aluminum, with the large exception of all the magnesium skin of the B-36 which was painted silver because of corrosion concerns. and what F-51Ds were left in service, which always had puttied, sanded and painted wings for “laminar flow”. Red “Arctic” rescue markings on wingtips and tails of airplanes that operated or might operate over the northern USA/Canada/Alaska/Arctic Ocean.
Anti-(nuclear)-flash glossy white paint appeared underneath Strategic Air Command’s bombers, and all insigna or other color was removed from the area painted white, during the 1950s.
As the massive massive military build-up of the 1950s gave way to even more expensive and thus fewer planes in the 1960s, problems with corrosion on bare aluminum were noticed. The KC-135 looked just like a Boeing 707 but although they shared wing design, at first, the fuselage was built on different tooling, 6″ narrower, and the whole airplane was made of different alloys than were used for the commercial version. When corrosion became a maintenance issue, the fleet was painted in an aluminum colored polyurathane similar to that used on the top and bottom wing skins of 707s and other big airliners. F-5s intended for the Military Assistance Program were originally specified for bare metal but also painted in aluminum polyurathane.
USAF 1960s, USA and Europe. ADC light gray for F-102s, F-101s and later F-106s in the USA, perhaps in Europe too. “Natural metal”, which might or might not be Corogard aluminized laquer, on bombers, fighters, transports, etc.
F101s, F106s and for a time, F110s (aka F4s) in Air Defence Command dispensed with bare metal and were painted a light, glossy, gray starting in 19??. The color called “Canadian Voodoo Gray FS 16505” is related to the “Air Defence Command (ADC) Gray” 16xxx.
USAF mid-late 1960s, Vietnam. South East Asian 4 tone scheme or “natural metal”, which was actually aluminized laquer corrosion inhibiter in some cases (Corogard- KC-135s and F-5, for example). F-4C and Ds operated in Air Defence Command glossy light gray initially, and F-105s, F-100s, F-101s, B-57s, etc. operated in ‘natural metal’ initially
As the bare metal look proved a liability in Vietnam, a South East Asian scheme of beige, olive green, dark green and light gray was applied to F-100s, F-4s, B-26s, B-57s, C-130s, C-123s, EC-121s, etc.
A series of darker tones was codified for Europe, called “Euro-lizard I and II” and “Charcoal Lizard”. These featured a pair of greens, a darkish gray and a gray underside. F-4s, C-5, C-130, C-141 transports, A-10As, RB-66s, F-15E bombers,, etc, wore these colors
USAF, later 1970s, used Ghost Gray/ Compass Gray in light and dark to confuse the outline of F-15s, F-16s, A-10s, and later F-4s. Generaly the underside and outer parts of the upper sides were the light gray, the middle of the wing and fuselage had an irregular blob of the darker gray. Black or dark gray national markings. USAF landing gear wells, door insides and legs finally went all white during this time. A-7s, older F-4s, etc, usually retained the “TAC” four-color markings for South East Asia- tan, light green, dark green and a pale gray underside B-57s, A-1s, F-105s, F-101s, F104s and F-102s all wore these colors. Night-flying B-52s, B-57s and AC-130s had glossy black undersides, with the B-52s carrying their unique “SAC” topside colors and the “TAC” colors on B-57s and AC-130s. C-130, C-121, C-123 and C-47/C-53 tactical frieght haulers wore the South East Asia scheme as required.
USAF later 1970s, European theatre, used “Euro-lizard” colors- green, olive green and blue-gray upper surfaces, light gray lower surfaces. This was the factory finish for later A-10As, C-5Bs, some F-4s. F-15s, F-16s, never wore these colors. C-141s, As and Bs, did. None of the century series (F-100, F-101, F-102, F-104, F-105, F-106) wore these, at least as far as I know.
Air Force Colors Volume 1, 1926-1942, Dana Bell. Squadron/Signal Publications, (C) 1979, ISBN 0-89747-091-5 Illustrated by Don Greer and Rob Stern.
Air Force Colors Volume 2, Dana Bell. Squadron/Signal Publications, (C) ISBN Illustrated by Don Greer and Rob Stern.
Air Force Colors Volume 3, Dana Bell. Squadron/Signal Publications, (C) , ISBN Illustrated by Don Greer and Rob Stern.
USAAF Aircraft Markings and Camouflage 1941-1947, The History of USAAF Aircraft Markings, Insignia, Camouflage, and Colors Robert D. Archer, and Victor G. Archer Schiffer Publishing (C) 1996.http://www.us-aircraft.com/research_topicswingedflight.htm http://.ipmsstockholm.org/colorcharts/stuff_eng_colorcharts_us.htm