The Boeing B-17’s color palette, with equivalent FS numbers where applicable.
Excerpts taken from:
Boeing Aircraft Company. Erection and Maintenance Instructions for Army Model B-17F/British Model Fortress II. 1 December 1942. Revised, Indianapolis, IN: William H. Burford Printing, 15 September 1943.
While these excerpts are taken from a F-type B-17 manual, the instructions given here changed little throughout the wartime B-17 series.
[EXCERPT ONE – BEGINS]
3. REFINISHING
a. GENERAL. – All interior, exterior, and detail finishing must be in accordance with Boeing finish Specification No. D-2304, which consolidated the general U.S. Army Specification No. 3-100-H with the Boeing B-17F airplane detail Specification No. D-2163-F. The following summary shall be used as a guide only, and reference should always be made to the specification for final authority.
(1) All interior and exterior parts fabricated from steel, except corrosion-resistant steel and armor plate, shall be cadmium plated only.
(2) Springs shall not be cadmium plated.
(3) All interior and exterior parts fabricated from aluminum alloys shall be anodized only except those from the following alloys: 24ST ALCAD ALUMINUM ALLOY; 17ST ALCAD ALUMINUM ALLOY; 3S ALUMINUM ALLOY; 52S ALUMINUM ALLOY; and 2S ALUMINUM.
(4) Aluminum alloy parts may be anodized after assembly.
(5) The interior surfaces of the wings, stabilizer, fin, nacelles, body, and those surfaces behind the sound-proofing and control surfaces shall not be painted regardless of the material used, except as follows:
(a) The interior exposed metal surfaces in the control cabin shall be finished with one coat of primer and one coat of dark green lacquer after installation.
(b) The interior surfaces of fabric-covered control surfaces only shall be finished with one coat of primer and one coat of carbon black tinted primer after the structure is as complete as possible.
(6) Seats, tables, and other such items need not be painted, except as noted in paragraph (14).
(7) The surfaces between the outer skin of the wings and the corrugations panels shall not be painted.
(8) All surfaces inside the wing in the vicinity of the fuel tanks shall be sprayed with two coats of zinc chromate primer as a spark inhibitor.
(9) The floor of the lavatory compartment and all parts and structure directly below the floor, as well as the side walls for a distance of 12 inches above the floor, and around the toilet seat shall be given one coat of acidproof paint.
(10) Air ducts and parts attached to air ducts shall not be anodized or painted inside or outside.
(11) The interior surfaces of the chords of the wing spars, the interior surfaces of the body bulkhead chord members at stations 4 and 5, and of the diagonal bulkhead members between the chords at station 4 and station 5 shall be coated with P-27 primer after the riveting is complete.
(12) The surfaces between the corrugation and the outer sheet of the floors shall not be painted.
(13) The exterior metal surfaces of the airplane shall be finished with one coat of camouflage paint, with color combinations in accordance with U.S. Army Specification No. 24114. No priming coat shall be required. The interior of the inboard nacelles and the inside of the bomb doors shall not be camouflaged.
(14) The top surface of wood tables in the navigator’s compartment shall be finished as follows:
Surfacer – 1 coat (Fuller’s No. 1705 or equivalent)
Dark green lacquer – 2 coats
(15) Cables shall be dipped in hot 71°C (160°F) heavy rust preventive compound, U.S. Army Specification No. 2-82.
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(16) Interior surfaces of cowling shall not be painted.
(17) No paint coating shall be applied to either side of the fire wall, or to parts and surfaces of the engine section forward of the fire wall.
(18) Aluminum alloy parts attached directly to fire wall sheet shall be anodized only. Steel parts, other than corrosion-resistant steel, attached directly to fire wall sheet shall be cadmium plated only. Additional insulation, between dissimilar metals of fire wall and parts attached thereto, shall not be required.
(19) Rubber and rubber-like surface shall not be painted or greased.
(20) The outer seams of the fuselage covering shall be sealed with liquid sealing compound (zinc chromate compound).
(21) The surfaces in contact and faying surfaces of cadmium plated steel parts and cadmium plated copper alloys with aluminum, Alclad or anodized aluminum alloys shall be assembled without paint. The surfaces in contact and the faying surfaces of anodized aluminum alloy, aluminum, and Alclad, in any combination, may be assembled without paint.
[EXCERPT ONE – ENDS]
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[EXCERPT TWO – BEGINS]
(2) MATERIALS AND WORKMANSHIP
(a) ALUMINUM PAINT COATINGS
1. The following table gives the recommended quantities of aluminum powder, or paste, conforming to Federal Specification No. TT-A-468, to be used where aluminum pigmented paint coatings are specified. The quantities are based on 1 gallon of package material before reduction.
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2. Whenever carbon black tinted primer is specified, it shall consist of, or be equivalent to, 8 ounces of carbon black tinting paste (Fuller’s No. SP 790 or equivalent) per gallon of zinc chromate primer.
(b) CLEAR PRIMER FOR ALUMINUM COATED (ALCLAD) ALUMINUM ALLOYS. – A clear varnish type coating, such as material conforming to Federal Specification No. TT-V-121, may be used as a shop coating to prevent scratching of the sheets during fabrication. This coating or additional coats, if necessary, may be used as the primer coat on interior surfaces.
(c) GREEN FINISH. – The dark green lacquer for the control cabin, radio compartment, except camera compartment, and the bombardier and navigator’s compartment shall be duPont Duco No. 258-38154, Berry Bros. Berryloid bronze green lacquer No. 234G9, or the equivalent.
(d) EXTERIOR METAL SURFACES. – The external metal surfaces of the airplane shall consist of material which, as specified in AAF Specification No. 3-100-H, do not require an additional organize protective coating.
[EXCERPT TWO – ENDS]
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[EXCERPT THREE – BEGINS]
(j) FINISH FOR INTERIOR PARTS AND SURFACES
1. The interior surfaces of the wings, stabilizer, fin, nacelles, body, and those surfaces behind the sound-proofing and control surfaces, shall not be painted regardless of the material used, except as follows:
a. The interior exposed metal surfaces in the control cabin shall be finished with one coat of primer and one coat of dark green lacquer, (duPont No. 258-38154, or Berry Bros. Berryloid Bronze Green Lacquer No. 234G9 or the equivalent) applied after installation.
b. The interior surfaces of fabric covered control surfaces only, shall be finished with one coat of primer and one coat of carbon black tinted primer, after the structure is as complete as possible.
c. Seats, tables and other like items need not be painted, except as noted in paragraph (4)(l).
2. All instrument boards shall be finished with one coat of dull black lacquer (duPont Duco No. 258-2801, or equivalent).
3. The surfaces between the outer skin of the wings and the corrugation panels shall not be painted.
4. Zinc chromate primer (Specification No. AN-TT-P-656) shall be used whenever primer is specified.
5. The floor of the lavatory compartment, all parts and structure directly below the floor, the walls for a distance of 12 inches above the floor, and the surface around the toilet seat shall be given one coat of acid-proof paint, (Federal Specification TT-V-51, grade B) over the specified finish. This is applied after installation of the parts, except that the surfaces of the body
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covering and the frame, which are in contact, shall be coated prior to assembly.
6. A spark inhibiting finish of two coats of zinc chromate primer shall be given all surfaces inside the wing in the vicinity of the fuel tanks. The area to be finished shall extend from rib stations 1 to 13 inclusive, 12 inches forward of the front spar and 12 inches aft of the rear spar. This area shall not be masked off for painting purposes. The exterior surfaces only of metallic fuel tank shells shall be given two coats of zinc chromate primer.
7. Bolts, screws, and rivets shall not be painted prior to installation. Steel bolts, screws, and rivets shall be cadmium plated only. Aluminum alloy bolts, screws, and rivets shall be anodized only.
8. Air ducts shall be finished as follows:
a. All hot and colt air ducts which are part of the heating and ventilating system, or which are a part of the engine air intake system and intercooler system, shall not be anodized or painted inside or outside.
b. Parts which are attached to the air ducts need not be anodized or painted.
9. The inside surface of electrical conduit shall not be coated.
10. Bomb rack parts shall not be painted.
11. Rivet heads on unfinished or primed surfaces, or on surfaces which are finished before riveting, shall not be touched up except as follows: The interior surfaces of the chords of the wing spars, the interior surfaces of the body bulkhead chord members at stations 4 and 5, and of the diagonal bulkhead members between the chords at stations 4 and 5, shall be coated with P-27 primer, after the riveting is complete.
12. The surfaces between the corrugation and the outer sheet of the floors shall not be painted.
13. Clear varnish (Federal Specification No. TT-V-121) may be used as the primer coat for interior surfaces fabricated from aluminum-coated aluminum alloy (Alclad) sheets. On assembly, the interior finish for such surfaces shall be completed by applying top coats in accordance with paragraph (j)1. above.
(k) FINISH EXTERIOR PARTS AND SURFACES
1. Fabric covered surfaces shall be finished with camouflage dope in accordance with AAF Specification No. 24114.
2. The exterior metal surfaces of the airplanes shall be finished with one coat of camouflage paint, with color combinations in accordance with AAF Specification No. 24114. No priming coat shall be required. The interior of the inboard nacelles and the inside of the bomb doors shall not be camouflaged.
3. Anti-glare coating, one coat of metal primer followed by one or more coats of flat bronze green Lacquer or enamel, shall be applied to eliminate glare on such surfaces, as fuselage deck, forward of pilot’s compartment, and inboard side of engine nacelles, as required.
4. Cocardes shall be applied in accordance with paragraph E-3 of AAF Specification No. 24114.
(l) FINISH FOR WOOD SURFACES.
1. All interior wood surfaces shall be finished to match adjacent surfaces except as follows:
a. All wood doors and floors, the top surface of the wood tables in the navigator’s compartment, and all wood surfaces adjacent to unpainted structure shall be finished with 2 coats of clear lacquer (Fuller’s Synalac clear finish No. 7700, or its equivalent).
[EXCERPT THREE – ENDS]
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[EXCERPT FOUR – BEGINS]
c. FINISH CODE NUMBERS. – The finish required is indicated on the drawing by the code number. This code
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Number consists of BF3 followed by one of the following dash numbers, (such as BF3-15):
15. Anodize.
17. Anodize.
Primer – One coat.
20. Anodize.
Primer – One coat.
Lacquer – Dull black – one coat (Duco No. 258-2801, or equivalent).
21. Anodize.
Primer – One coat.
Lacquer – Dark green – one coat (Duco No. 258-38154, or equivalent).
35. Cadmium plate.
37. Cadmium plate.
Primer – One coat.
38. Primer – One coat.
41. Flat springs, steel.
Acid bath, 1 minute. Cyanide bath, dip only.
Cadmium plate.
Bake after plating, 5 hours at 204°C (400°F).
42. Sandblast.
43. Sandblast (do not pickle).
Primer – One coat.
44. Corrosion resistant steel parts which have been welded, annealed, etc. Immerse in a solution containing 50 percent by weight of hydrochloric acid at 54° – 60°C (130° – 140°).
Rinse in hot water.
Passivate by immersing in a solution containing 15 percent by weigh of nitric acid at approximately room temperature for 20 minutes.
Rinse thoroughly with hot water.
45. Cadmium plate.
Primer – One coat.
Lacquer – Dull black – one coat (Duco No. 258-2801, or equivalent).
46. Coat the inside of closed hollow ferrous parts with raw linseed oil in accordance with U.S. Army Specification No. 3-100, paragraph E-9.
47. Cadmium plate.
Primer – One Coat.
Lacquer – Dark green – one coat (Duco No. 258-38154, or equivalent).
48. Clean, coat with rust preventative compound, U.S. Army Specification No. 2-82.
49. Sun resisting rubber paint – Two coats (Goodrich No. 02-TK-132 or equivalent).
54. Cadmium plate – Ferrous parts.
Anodize – Aluminum alloy parts.
Primer – One coat.
55. Cadmium plate – Ferrous parts.
Anodize – Aluminum alloy parts.
57. Cadmium plate – Ferrous parts.
Anodize – Aluminum alloy parts.
Primer – One coat.
Lacquer – Dull black – one coat (Duco No. 258-2801, or equivalent).
58. Cadmium plate – Ferrous parts.
Anodize – Aluminum alloy parts.
Primer – One coat.
Lacquer – Dark green – one coat (Duco No. 258-38154, or equivalent).
67. Primer – Two coats.
68. Primer coating inside of tubes, etc.
70. Acidproof paint – One coat (Federal Specification No. TT-V-51 grade B).
72. Acidproof paint – Two coats (Federal Specification No. TT-V-51 grade B).
73. Rust-preventative coating for control cables (U.S. Army Specification No. 2-82). Dip in rust preventative at 71°C (160°F) and drain.
78. Lacquer – Dull black – two coats (Duco No. 258-2801, or equivalent).
81. Lacquer – Dark green – one coat (Duco No. 258-38154, or equivalent).
82. Aluminum tanks (except water tanks).
Flush inside with Calot flushing oil, or equivalent.
83. Primer – One coat.
Lacquer – Dull black – one coat (Duco No. 258-2801, or equivalent).
87. Olive drab camouflage enamel – One coat (U.S. Army Specification No. 14109).
88. Neutral gray camouflage enamel – One coat (U.S. Army Specification No. 14109).
92. Nitrate dope – Semi-pigmented – three coats – brushed.
Nitrate dope – Aluminum pigmented – three coats – sprayed.
93. Nitrate dope – Yellow semi-pigmented – three brush coats, Specification No. AN-TT-D-556.
Nitrate camouflage dope – Fully pigmented – at least two spray coats as required, U.S. Army Specification No. 14106.
98. White surfacer – One coat (Fuller’s Synalac industrial lacquer No. 7799, or equivalent).
Dark green lacquer – Two coats (Duco. No. 258-38154, or equivalent).
99. Clear lacquer – Two coats (Fuller’s Synalac clear finish No. 7700, or equivalent).
100. Magnesium and magnesium base alloys.
Chromate treatment – in accordance with U.S.
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Army Specification No. 98-20010.
101. Aluminum alloy bolt and rivet spacers shall not be anodized or painted.
122. Anodize.
Primer – One coat.
Carbon black tinted primer – One coat.
130. Cadmium plate.
Primer – One coat.
Carbon black tinted primer – One coat.
184. Zinc chromate primer – One coat.
Carbon black tinted primer – One coat after assembly.
186. Carbon black tinted primer – One coat.
[EXCERPT FOUR – ENDS]