P-47 Cockpit

[Juggernut]

There is a Republic Aviation Corporation document No. 520, Finish Specifications that is listed under both Appendix IC and Appendix IIA - Deviations, Non-Standard Parts and Exceptions  to the Requirements of the Procuring Agency for the P-47D Model Specifications, Revision G, dated 02-AUG-1944.  I sent a request to the NASM to see if they might have a copy of this document.  I believe that in there will be found the appropriate deviations for using dull dark green over what the procuring agency, aka "USAAC" specifications called for.  If they do have a copy of this document, I will purchase it and we will see what it contains.

 

As far as the dull dark green color being oversprayed on a different color, there is evidence for the practice in a post above where the E&R manual calls out that cockpits are to be painted in untinted zinc and then overcoated with tinted zinc to prevent glare caused by untinted zinc.  The question is not whether this was done; as you point out, the photos I posted seem to look like the dull dark green was applied over a lighter color.  The question is whether this was done at the factory or some overhaul facility someplace.  Given what I said previously about the E&R manual not necessarily being used at the factory, the reverse is not true as the E&R manual was developed (as was usually the case) by the Engineering department and what is being shown through the dull dark green is in fact, untinted zinc primer; both having been applied at the factory.

 

Damian,

 

I agree that 1 part untinted zinc and 1 part black will most likely yield a color darker than the accepted interior green, nonetheless, it is in the ballpark (which is why I used the term "akin") albeit a bit closer to olive color.  I'll do an experiment with my hobby paint and see what I get.  If I can get a good color balanced photograph  of the result, I'll post it here.   I'm sure you are aware that other monitors may alter the color and it may or may not appear as the original was posted.

 

Of note is that the P-51 Mustang "Yellow-Green" was comprised of "1-gallon Zinc Chromate (Yellow) primer, 1-gallon  Toloune Substitute, 1-gallon black enamel or paste, and 4 ounces of aluminum powder which was later deleted."  The mixed color resulting from these components was coded with "ANA611, FS595/34151." (O'Leary p. 46). I believe this to be what was referred to as "North American Green".  Although coded ANA611, I do not think this color mix matched the later, standardized, ANA611.

 

REFERENCE: O'Leary, Michael.(2010). Building the P-51 Mustang, The Story of Manufacturing North American's Legendary World War II Fighter in Original Photographs. Specialty Press. MN.

 

Edited March 18, 2021 by Juggernut
Edited for readability, clarity of premise, and continuity with previous posting.

[Derek B]

56 minutes ago, D.B. Andrus said:

Hi Derek

 

Could you post the ratios from the P-61 E & E manual? I'm curious how Northrop approached this color.

 

Cheers,

Damian

 

Damian,

 

This is from July 2013 from the p-61 E & M manual:

 

 

The Erection and Maintenance tech order-- the "Dash Two" manual-- for early P-61A aircraft specifies the following painting requirements for olive and gray P-61s: "All aluminum and aluminum alloy surfaces shall be coated with two coats of zinc chromate primer, Spec.No. AN-TT-P-656, before receiving final paint finish, except when darkened zinc chromate primer is final finish, in which case darkened prime may be applied as a preliminary coat. no touch-up of primer is required prior to painting exterior finish." "Insignias, numerals and markings shall conform to customer's requirements and engineering drawings. Diameter of all cocarde circles shall be 25 inches. Decalsomanias or rubber (insoluble ink) stamps may be used for markings. All lettering shall be in insignia dull red, including radio call letters, shade No. 45 AAF bulletin No.41-A." "Fabric covered surfaces shall be doped with clear nitrate dope and camouflage dope until desired tautness is obtained. the following doping procedure shall be followed for all fabric surfaces: Three or more coats of clear nitrate dope by hand brush, Spec.No. AN-TT-D-514, and three or more coats by spray. One or more coats of pigmented dope, AAF Spec.No. 14106, No. 41 or 43 camouflaged dope to match surfaces as per AAF bulletin No. 41-A." "All upper surfaces shall be camouflaged with one coat of dark olive enamel, AAF Spec.No. 14109 and all under surfaces shall be camouflaged with one coat of neutral gray, shade 43 (AAF 14109)." "Insignia colors shall be dull finish and equivalent to the following shades: Insignia White AAF 14109-A No. 46; Insignia Blue AAF 14109-A No. 47." "Landing gear assemblies shall be left unpainted. No camouflage finish is required on the interior surfaces of the wheel wells."

 

"All exposed interior surfaces of the gunner's, pilot's and radio operator's compartments shall be finished with Northrop Cockpit Green (12 oz. of black camouflage enamel AAF 14109 to one gallon of zinc chromate primer Spec.No. AN-TT-P-656). this includes the seats and all other interior parts and surfaces except the instrument panels which will be dull black. Interior surfaces visible from the exterior shall be finished with one coat of dull enamel, AAF Spec.No. 14109 to match exterior surfaces. All unexposed interior surfaces of the gunner's, pilot's and radio operator's compartments, as between the flooring and the crew nacelle bottom, shall be coated with zinc chromate primer only, Spec.No. AN-TT-P-656. All exposed interior surfaces and parts of the turret compartment shall be finished with two coats of darkened (yellow-green) primer, Spec.No. 3-100-I. Unexposed interior surfaces of the turret compartment shall be finished with zinc chromate primer, Spec.No. AN-TT-P-656. All interior surfaces of the cannon compartment shall be finished with two coats of darkened primer (yellow-green), Spec.No.3-100-I."

 

Clearly, the proportions for 'tinted green' (in this case, 'Northrop Green') can vary slightly from manufacturer to manufacturer of different aircraft types, but the intent was probably the same - I guess that this was the case until it was standardised. 

 

Derek

Edited March 18, 2021 by Derek B

[Johnny Cloud]

14 hours ago, Juggernut said:

There is a Republic Aviation Corporation document No. 520, Finish Specifications that is listed under both Appendix IC and Appendix IIA - Deviations, Non-Standard Parts and Exceptions  to the Requirements of the Procuring Agency for the P-47D Model Specifications, Revision G, dated 02-AUG-1944.  I sent a request to the NASM to see if they might have a copy of this document.  I believe that in there will be found the appropriate deviations for using dull dark green over what the procuring agency, aka "USAAC" specifications called for.  If they do have a copy of this document, I will purchase it and we will see what it contains.

 

As far as the dull dark green color being oversprayed on a different color, there is evidence for the practice in a post above where the E&R manual calls out that cockpits are to be painted in untinted zinc and then overcoated with tinted zinc to prevent glare caused by untinted zinc.  The question is not whether this was done; as you point out, the photos I posted seem to look like the dull dark green was applied over a lighter color.  The question is whether this was done at the factory or some overhaul facility someplace.  Given what I said previously about the E&R manual not necessarily being used at the factory, the reverse is not true as the E&R manual was developed (as was usually the case) by the Engineering department and what is being shown through the dull dark green is in fact, untinted zinc primer; both having been applied at the factory.

 

...

 

That's great, let’s hope the NASM comes through with document No. 520, it could really answer some old questions.

 

I do not think the repaint of 44-32691 is a factory job, the DDG paint looks to have been applied quickly around the placards, switch-boxes etc…  
Most of these elements would have been installed at the factory after painting, not before.
There's even some overspray on a few parts and cables.

I do disagree with one thing; in my opinion the color seen underneath is not YZC.
While a few small YZC parts can be spotted in the cockpit,  the color under the coat of DDG looks very much like a cockpit green, in my opinion quite similar to the color found by Aircorps Aviation in the P-47 they’re restoring.
Here’s a detail from NASM cockpit showing the DDG paint over the lighter green and you can also see a YZC part inside the wall behind the throttle quadrant.

The green undercoat is not YZC and it cannot be DDG, there are three colors.

 

The problem here hinges on something Dana said: there were variations of DDG.
We are used to think of certain colors as recipes and know what to expect when looking at them (ANA-611, RLM66 etc...)
DDG is apparently different,  rendering its identification difficult.
At this point one can look at the cockpit of Dottie Mae and "correctly" claim it to be DDG even though it looks nothing like other much darker known DDG samples.

Edited March 19, 2021 by Johnny Cloud
Clarity

[Derek B]

On 3/18/2021 at 2:36 AM, D.B. Andrus said:

Juggernut

 

Respectfully, 1 part Zinc Chromate + 1 Part Black would yield something much darker than Interior Green. The original formula for Tinted Zinc Chromate is 1 gal ZC + 1/10 gal  Black enamel + 4 oz aluminum paste. Later the aluminum paste was deleted and the result named Interior Green. Later still, a pre-mixed Interior Green came into general use. As for DDG, that remains, to me at least, a wriggling can of worms.

 

Cheers,

Damian

 

Quote

Northrop Cockpit Green (12 oz. of black camouflage enamel AAF 14109 to one gallon of zinc chromate primer Spec.No. AN-TT-P-656)

 

I cannot find my original test batches a the moment (they must be buried in my P-61 files somewhere).

 

my experiment to mix the Northrop cockpit green iaw the E & M manual was very crude and subjective, but did serve to provide a colour which was somewhere near the intent of the manual mixture guidance (and probably suitable for representation on a model).

 

I placed ten large equal sized droplets of Humbrol zinc chromate yellow primer (Humbrol Authentic HD4) paint into a dish with a single (same size) drop of black (Humbrol 33 matt black) and thoroughly mixed them before painting it onto a piece of white card. I then repeated this exercise twice more, with the same (unchanged) quantities of zcy paint, but fractionally more black and fractionally less black.

 

The results were that the first mix produced a Northrop cockpit green colour not dissimilar to the DDG seen in P-47 cockpits. The mix with slightly more black turned out closer to dark olive drab in colour (almost black-green) and the slightly less black mix came out as a light olive green colour (akin to DDG sprayed very lightly over zcy colour, or nearer to the lighter green colour seen in some B-17 cockpits).

 

I am certain that others can measure the quoted mix proportions in model paint far more accurately than I did and assess the results, which, as long as they are not way off (there will undoubtedly be variations), may well be useful as representations of the DDG colours as seen in both P-61 and P-47 cockpits.

 

Cheers

 

Derek

[D.B. Andrus]

Thank you, Derek!  I like your methodology on mixing paint. Very interesting information.....the earlier data of 1/10 gal. of black to 1 gal. of ZC would yield 12.8 oz of black. Similar indeed.

 

Cheers,
Damian

[MikeMaben]

Trying to shoot for a specific color for primer is pointless. There were these formulas per spec

but when it came time mix them prior to application, unless they used precise measuring equipment,

there had to be variations. Even today, when I inspected paint at Boeing, mostly structural and detail

components, the primers were mixed usting tools but they differed substantially due to other factors

like temperature and how much time passed between mixing and applying. They didn't care one whit

about the color, it was a functional coating not a cosmetic one. Sounds like it was the same back then.

Point being , and I don't want to come off as a party pooper, but trying to match a chip or photo or a

specified formula from a manual / document is crapshoot. 

[Derek B]

8 hours ago, MikeMaben said:

Trying to shoot for a specific color for primer is pointless. There were these formulas per spec

but when it came time mix them prior to application, unless they used precise measuring equipment,

there had to be variations. Even today, when I inspected paint at Boeing, mostly structural and detail

components, the primers were mixed usting tools but they differed substantially due to other factors

like temperature and how much time passed between mixing and applying. They didn't care one whit

about the color, it was a functional coating not a cosmetic one. Sounds like it was the same back then.

Point being , and I don't want to come off as a party pooper, but trying to match a chip or photo or a

specified formula from a manual / document is crapshoot. 

 

Indeed Mike, which is why I chose my words carefully in order to indicate that, at best, it would only be representative because of some of the reasons you mentioned.

 

Cheers

 

Derek

[Johnny Cloud]

9 hours ago, MikeMaben said:

Trying to shoot for a specific color for primer is pointless. There were these formulas per spec

but when it came time mix them prior to application, unless they used precise measuring equipment,

there had to be variations. Even today, when I inspected paint at Boeing, mostly structural and detail

components, the primers were mixed usting tools but they differed substantially due to other factors

like temperature and how much time passed between mixing and applying. They didn't care one whit

about the color, it was a functional coating not a cosmetic one. Sounds like it was the same back then.

Point being , and I don't want to come off as a party pooper, but trying to match a chip or photo or a

specified formula from a manual / document is crapshoot. 

I think most of us would agree with you but when the time comes to put paint in the airbrush you have to make a choice.

Trying to figure that stuff out in a way that satisfies each of us individually is part of the fun.

[John1]

5 hours ago, Johnny Cloud said:

Trying to figure that stuff out in a way that satisfies each of us individually is part of the fun.

Part of “the fun” or part of “the illness”?    Asking for a friend.....

[John1]

Thoughts on the color of the large map case on the right sidewall?  Having a hard time discerning it from the available pics.  
 

Also - probably a long shot but if anyone has the HGW stencil and cockpit placard set and wants to part with it, please PM me.   Seems to be OOS pretty much everywhere.  

[Antonio Argudo]

 

[John1]

Antonio, thank you very much!  As with my F-51D build, you continue to provide some extremely useful information.  It's greatly appreciated. 

 

Regards,

 

John

[D.B. Andrus]

[John Stambaugh]

I read in detail and scale book that all Republic built P-47s cockpits were dull dark green and Curtis built were FS interior green. 

[John1]

Question - I’m building a D-30.  Would that version have the solid rudder pedals or the later “open” ones?    Also, would it have that center switch panel installed under the IP, between the rudder pedals?