USAAF P-40F in the desert: camo scheme ?

[Super Aereo]

I wish I could have your certainties on Russian use of paint, Graham...

However, white stoving enamel was prescribed for use on the cowlings of Coastal Comand aircraft with white undersides in August 1941.

The Russians used white distemper (MK-7) for winter camouflage which was made of caseine and chalk.

That is to say they covered the upper surfaces of their high-performance fighter aircraft with chalk powder kept in place with casein.

I also disagree with the idea that the American HQ could have been so totally incompetent, and the order was never revoked, as far as we know.

And I have transcribed excerpts from the two books I mentioned, and Archer seems to think that the order was actually followed in some cases ("Photographs of the time show that it was chiefly theA-20, B-25, and P-40 units that adopted the new camouflage").

At the end of the day, if aircraft could fly and fight when covered in chalk, I don't see why they would have a problem with high-quality Corps of Engineers paint, it is not as if they were to be covered in Zimmerit, is it..?

[Nick Millman]

There are some interesting aspects to the NWA HQ order and colours which I'll address at my blog idc rather than clog this up. I've also dug out some more on the P-40F schemes which I shall include there too.

"Chalk powder" sounds maverick but is in fact Pigment White 18 (CI 77220 & 77713) - natural calcium carbonate with magnesium carbonate as an impurity and known in pigment terms by many colloquial and proprietary names. Perfectly legitimate for making paint but more often used as an extender and matting agent with other pigments (although there are other attributed benefits including improved drying time).

Casein is a long standing medium for water soluble paints and has been used as such since ancient times. It is a phosphoprotein related to milk.

USAAF originally resorted to powdered pumice as a matting agent in aircraft paints for metal surfaces but later investigated the use of a thinner clear matting varnish to overcome the weight and surface roughness issues. I suspect from the timing, but have no evidence, that this was influenced by the concurrent RAF development of smooth paints.

[Test Graham]

Re Russian paint, I am going on the latest researches as discussed on the appropriate websites. If it is a matter of interest I suggest you look there. I suggest the comment, or at least the willingness to believe it, was also inspired by Cold War sneering at Russian inadequacies.

The Coastal Command ruling is interesting, and I wonder if this is related to the discolouration with heating? Being linked to the white scheme implies operations that do not call for flying near the limits of the envelope, not particularly high nor particularly fast. There was no such requirement placed on Fighter Command's cowlings. Also, the engine cowlings are a small portion of the total aircraft, so the weight penalty would be small. The inevitable state of the Command's flying boats on their open mooring meant unavoidably low standards of aerodynamic cleanliness anyway.

Winter white camouflages are perhaps a special case, as with the other distempers used for night bomber operations by the Luftwaffe and applied with a broom. The RAF had distemper paints too, although I can't think of specific cases of their use. Of course not all winter camouflages were temporary distempers, some of the white coats seen on Bf109s certainly seem to be durable and hardwearing. That this is a high performance type is no coincidence.

The basic engineering principles stand. They could always be overruled in specific instances: however the number of such instances appear to have been much lower than the carefree claims made in "bar stories" or journalistic tales adopted a little too freely by later historians, unaware of the importance of a good finish and what is required to achieve this.

[Super Aereo]

I think the Tractor Green for GAZ 292 in Saratov comes from the fact that the factory itself did produce agricultural machinery before converting to aircraft production, so it might be a myth, but given that current debate (in English) about Russian paint is somehow rich in antagonisms and poor in documentation, people who declare it totally untrue seem to be doing so more out of spite for a certain author than out of any concrete information (unless I missed something).

A lot of legends often have a grain of truth in themselves.

This is just a personal consideration and no criticism of the excellent work carried out by Massimo Tessitori, mind you.

[Fernando]

Dark Earth and OD was a "standard" combination when OD was authorised to be used in place of Dark Green early in 1942 and in fact E's arriving in CBI in this scheme after a sojourn in India were often described as being in "desert colours" because of the fading qualities of the OD.

Nick

Hi, Nick,

Was OD (Dark Olive Drab n°41, at that date?) authorized to replace Dark Green (Du Pont equivalent colour?) on British order machines? I understand the Joint Committee approved Olive Drab ANA 613 to substitute Dark Green in June 1943.

Fernando, back at Nairobi

[Nick Millman]

Hi, Nick,

Was OD (Dark Olive Drab n°41, at that date?) authorized to replace Dark Green (Du Pont equivalent colour?) on British order machines? I understand the Joint Committee approved Olive Drab ANA 613 to substitute Dark Green in June 1943.

Fernando, back at Nairobi

Yes, the JAC authorised that as a substitute from March 1942 and it preceded the ANA agreement which standardised OD instead of Dark Green. Not surprising because OD 41 and MAP Dark Green standards were much closer in appearance (although not in ageing properties!) than some realise. Humbrol 30 has a lot to answer for!

Please bear in mind that other paint companies (like Fuller) were also supplying MAP equivalent paints to US aircraft manufacturers, not just Du Pont.

Nick

[PFlint]

... given that current debate (in English) about Russian paint is somehow rich in antagonisms and poor in documentation, people who declare it totally untrue seem to be doing so more out of spite for a certain author than out of any concrete information.

very true !

the best method is scientific and chemical analysis of surviving paint samples.

sadly , there aren't many of them.

those people who are against that certain author don't seem to know of this scientific analysis and don't care.

their complete faith in paperwork only is where they go wrong.

[Fernando]

Hi, Nick!

Never heard about that one, OD n°41? I understand there were a number of American paint producers (Berry Bros. come to my mind); I mentioned Du Pont (the best known?) because it the one in the P-40 camo drawings in Dana's article.

Yes, H30 was taken as the paramount RAF Dark Green for years. I have not seen an original one for some time, but I remember it being closer to Medium Green 42 or aprox. FS34092? Remember the near equivalent you gave once for DG is 34083, but I still find it a deeper green than OD n° 41.

Is there any means of gaining access to your blog (or getting one of the works you were preparing)?

Yours, Fernando

[Nick Millman]

FS 34092 is the usual match given for Medium Green 42 but compared to the standard chip it is just a little too blue. Whistler describes it as a good match but Smith considers 42 to be less blue and more yellow - describing it as "more a natural green" - with which I concur. For 1/72nd scale FS 34128 gives a better impression of the hue - although a shade too light for the full scale colour.

FS 34092 superceded ANA 612 Medium Green which in turn replaced 42 which is where the connection originates.

An important point to make here is that the pigment specification for 42 was 'optional' for manufacturers and there is a difference between two suggested formulae one of which includes blue pigment. Also the iron oxide pigment required was not closely specified and varied from reddish brown through yellowish ochre to orange which affected the degree of olive appearance in the paint and was probably intended to be countered by the blue pigment in order to correctly match the standard and create the appropriate contrast to the OD. The formula for 34092 is slightly different in that it includes carbon black (blue shade), benzimidazolone yellow rather than iron oxide and phthalo green rather than chrome oxide green.

WEM's ACUS16 Medium Green 42 gets the standard hue right but probably needs to be lightened a little on a model.

You should be able to access my blog directly - there are no restrictions. Let me know if you have problems. Availability of various works in progress will be included there.

Nick

Edited January 1, 2013 by Nick Millman

[Giorgio N]

There's a lot of interesting information coming here ! As my kit represents a long tailed F I understand that a DE/MS/AB scheme is the safest bet, although an aircraft with OD/MS would look that bit different from other desert based aircrafts.

I found the picture mentioned by Nick of 42-10511, it would be an interesting subject. Would the 45 degree letters decal sheets available be the right shape to reproduce the wartime USAAF serial numbers ?

[old thumper]

I was just looking through here hoping to find some info on desert painted P38's and noticed a couple of comments about the RAF using stove enamel on engine cowlings. It was the collector rings that were painted with stove enamel not the entire cowling, the collector rings were of course full of gases and got very hot.

[Nick Millman]

I was just looking through here hoping to find some info on desert painted P38's and noticed a couple of comments about the RAF using stove enamel on engine cowlings. It was the collector rings that were painted with stove enamel not the entire cowling, the collector rings were of course full of gases and got very hot.

Stoving enamel refers to the method by which that type of paint is cured - in an oven - not its application. High-heat resistant paints and coatings are often referred to as stove enamel or stove paints, usually with a given maximum temperature resistance.

The P-38s, like other types, simply had sand paint applied haphazardly over the OD. The question of which sand paint is an interesting one but unlikely to be resolved since they were field rather than factory finishes.

[old thumper]

Stoving enamel refers to the method by which that type of paint is cured - in an oven - not its application. High-heat resistant paints and coatings are often referred to as stove enamel or stove paints, usually with a given maximum temperature resistance.

The P-38s, like other types, simply had sand paint applied haphazardly over the OD. The question of which sand paint is an interesting one but unlikely to be resolved since they were field rather than factory finishes.

Are you saying it is pretty much anyones guess what pattern of camouflage the P 38s had?

I did think that some kind of sandy colour over olive drab would be a likely scenario, possibly A20 style from what I have seen in a couple of pictures but others seem to think differently.

[Nick Millman]

Well, the scarce photos provide a clue as to pattern(s) but whether the paint was the same as the official Sand(s) is another matter.

Gen Arnold issued an instruction on 24 April 1942 that Sand, Shade No.26 was to be used on the upper surfaces of aircraft operating over sandy or desert terrain (T.O. 07-1-1, 6 May 1942). Wright Field ordered "ample quantities" of water paint, brushes, buckets, etc., to facilitate that.

In May 1942 it was decided to create a permanent camouflage enamel of Sand 26 for 98th BG aircraft that could be applied as a solid coat over the existing OD, retaining the Neutral Gray under surfaces. This permanent paint (colour) was then added to Bulletin 41 as Sand 49 in October 1942.

T.O. 07-1-1 issued on 1 June 1942 specified at Para 1b that temporary camouflage materials to Spec 14057 (Paint, Water Dry) could be applied over existing permanent camouflage as required and directed by Commanders in the Theatres of Operations. And Gen Arnold's requirement for Sand 26 was re-iterated in that order.

Then in March 1943 came the HQ NW African Air Forces order for theatre camouflage which included a P-38 schematic showing Sand 49 over OD 319 (US Corps of Engineer Colors) with under surfaces painted a mix of Light Blue 307 and white 12%/88%.

So a Sand over an OD seems a logical explanation for the appearance of lighter patchwork schemes over P-38s factory finished in OD and operating in N.Africa.

FWIW I've got a blog article on development of US Sand 26 in preparation (since September!) and will be including the US Corps of Engineer colours in that.

PS The evolution of the colours was Sand 26 (1939), Sand 49 (1942), 313 (US Army Spec 3-1 1943), ANA 616 (1943), 3025 (TT-C-595 1950), FS 30279 (FS 595 1956). In Army parlance it was referred to as 'Desert Sand'. Not to be confused with US Army Sand 306 (US Engineers No.3) which became Class 212 in ES-680 and evolved into FS 30277.

[old thumper]

Thanks, it is just that I plan to build a number of North African theatre USAAF aircraft in the future and I am trying to find out what I can in the mean time before I get the kits and start putting them together etc. The P38 is the aircraft that I'm most interested in doing and also the one that is most difficult to find anything about.

[tonyot]

Were the Op Torch P-40F`s not originally ordered as Kittyhawk MkII`s from RAF contracts which were finished in the desert scheme and then re allocated to the USAAF with US serials? Seems the most logical reason to me?

Cheers

          Tony