American Volunteer Group P-40 Tomahawk colours?

[HBBates]

... The fact that US production was about raising issues at the end as opposed to the British method of oversight of the product through production. .... Or the fact that there were not enough individuals for British style oversight.

Hi all one thing on this... seems to be SOME British oversight of the Tomahawk production at the Curtiss factory ...note the button this man has on ...so is this a British goverment offical at Curtiss or a Curtiss employee working the British contract?

Edited August 20, 2011 by HBBates

[HBBates]

As for what color was the underside of the Tomahawk....Ive presented this before and I know many disagree but I just ask you take a second look

---First Photo

Above in the first photo you see a wing being built…note the chromate green already pre painted on the wing where the landing gearing faring will go (and sprayed past where the landing gear faring will go )…logical because this would be inside the landing gearing faring area so easier to paint now

---Second photo

Now look at this second photo… note the “gray” color around wing where the landing gearing faring is…

Now Dana Bell and others were of the opinion that gray is really natural medal scrubbed of it protective coating ….

But in the context on the first photo with the pre painted chromate green and overspray is that logical?…

I would expect to see the final inner landing gearing paint spray…

The last thing you would want under the edge of the landing gearing faring on the wing skin is raw unprotected medal

Why would you srub off the overspray on the wing in that one area that going to get painted over with the final under wing final color…

Yet leave yellow chromate on the landing gear faring itself and also the other overspray you see on the wing?

Ok so if that gray area is overspray paint not scrubbed natural medal why is it not chromate green like the first photo?

OK here is my theory /interpretation of these two photos…

The first wing with the chromate green already pre painted this is for a P40 and the US spec is this area on wing skin in and under the bolt on landing gear faring is to be painted chromate green like a wheel well

However the second photo is not a P40 but a Tomahawk…(note the black and yellow tip prop and earth spinner) so what the color around the landing gear faring?

My guess is the UK spec for the Tomahawk is this area on wing skin in and under the bolt on landing gear faring is ruled to be “"under wing"” not “"wheel well"”

So this area on wing skin in and under the bolt on landing gear faring is pre painted in the RAF undewing camo color and the overspray you seen the second photo is the famous sky/gray

Any way it just a theroy

Edited August 20, 2011 by HBBates

[Nick Millman]

(Apologies to others for the long and largely repetitive (of information elsewhere) post).

Just a point Nick, have you seen me advocating for the light gray in quite a while? I have merely taken the position that there is debate, that it was not Sky as we usually know it and I do point out the light greenish gray. But being said, and without having to go back to my notes, even that greenish gray gets slippery. IIRC, there was also a bluish aspect mentioned.

As for the corsairs, are you saying it was du Pont Sky Type S Gray, ANA 610 which would be the du Pont, or true British Sky Type S?

BTW, the P-61 specs called for two primer coats on surfaces, Northorp saved a lot of cash when it applied none.

"Advocating" light gray or casting doubt on Curtiss using an equivalent/approximate Sky-type colour seem to be two sides of the same coin. The other side of the "debate" on this has shifted from one where Curtiss (and other US manufacturers) were alleged to have been confused by the requirement for Sky so matched to Sky Grey instead to one where Curtiss deliberately deviated from spec requirements to save money. IIRC the story is that they bought cheaper (presumably) non-DuPont paints with colour names suggesting light greys (although there are no samples to confirm this), but curiously only for the under surfaces, evidenced from paint contracts recovered from a dumpster. There might or might not have been first name paint sprayers adding their recollections and showing souvenired bits of the aircraft they painted (must have been a shock when the aircraft arrived newly painted but missing some parts - "Those thieving paint sprayers at it again"!) and even a woman from the front office who remembers the colours - or is that for the Martlets and Corsairs? The original proposition for AVG under surfaces, however, seems to have been based mainly on the appearance of the colour in (some not all) colour photographs and various values have been attributed to this supposed light gray. The use of Tamiya Sky Grey became something of a modelling convention based on these ideas and spread to types other than Curtiss. It might be significant that these speculations were made before the character of the DuPont paint colour 71-021 was known or the DuPont MAP colour card was evidenced (see comment about the Tullis book above).

71-021 occupies a subtle colour space of pale blue-green. Whilst the Munsell value for it is a green-yellow (like Sky) the closest FS value of 25622 is blue predominant. People perceive the colour differently, some seeing it as more blueish, others as more greenish and some only see a light grey. That is a receptive and subjective aspect that does not relate to the actual measured colour values. Before discussing whether this pale blue-green is actually blue or green here is an online test you can take to assess your own colour acuity:-

FM100 Hue Test

It's fun. I scored 0 in the test (you don't want a high score).

I didn't say anything about the Corsairs - that was Ron Belling. He painted 6C - JT324 as a subject and describes it thus:- "The example shown clearly illustrates the contrast in colours when US-built aircraft were finished in approximate FS and BS equivalents. The top surfaces are FS Olive Drab and Sea Grey and the undersides Sky" so presumably he meant ANA 610. Throughout his book he refers somewhat prematurely to 'FS equivalents' but has much of interest to say about the differences between the UK and US substitute colours as well as documenting some very interesting schemes for P-40's, etc.

[Steven Eisenman]

The documents held by the RNZAF Museum are the 'Official Curtiss Aircraft Drawings" (which came with aircraft)

which give the paint types eg Dk Earth/ Dk Green/Sky etc and lists that the paint is DuPont

and the DuPont number with it

The Museum also has the Curtiss P 40E maintenace and erection manual which gives paint types

and numbers also.

Another thing I had totally forgotten about, is another E-mail from the 'Keeper

Of Records" (I found while searching for the original E-mail of above) at the museum.

He mentioned that there is photographic evidence of a P 40E wing held/had been held by a well known gent

in the Kiwi Aviation world (he has some complete examples of P 40N*/ Mosguito and aircraft parts etc all in

original paint schemes), this P 40E wing is in original US Equvalent colours which has the

lower section in a blueish colour.

(* This P 40N is the third Gloria Lyons)

(Unfortunately at the time, I didn't further query the photographic evidence (who/where),

though I have no reason to doubt the truth of his comments)

Further to my above comments after checking with other people I know who have met this gent:

This gent John Smith (is a real character)/his aircraft live in a place called Mapua in New Zealand.

John is quite private person (apparently) and does not allow photos of his collection to be published, to protect his privacy

and stop people hounding him to on sell his collection.

Kind regards

Alan

Thank you. But there is a throw away line that is interesting as the underside is described as a bluish color. Years ago, Dana Bell and Alan Griffith (a Curtiss fan and researcher) had strongly suggested that light blue had been used on the underside of Curtiss P-40s in the RAF scheme. Dana had published it in an issue of Fine Scale Modeler.

One thing about specs and plans, they are often parroted back and forth, and do not necessarily reflect reality. I come across this all the time in business practices. "I want you to do X and Y". The reply "we did X and Y". You actually go down to the operation and at bets only X was done, but more likely neither. We see that in mortgage foreclosure her with robo-signing. The clerks are instructed not to robo sign, they are told it is not correct. It is a matter of public record. The response is, of course we understand. Later it is discovered that it continued unabated because it was expedient. Having been a lawyer in corporations, I learned never to trust assertions of compliance.

Edited August 20, 2011 by Steven Eisenman

[Steven Eisenman]

Hi all one thing on this... seems to be SOME British oversight of the Tomahawk production at the Curtiss factory ...note the button this man has on ...so is this a British goverment offical at Curtiss or a Curtiss employee working the British contract? ]

According to Meekcoms, the shortage of inspectors resulted in Americans being taken on as inspector. Not going back to the book right now, but they may even have been manufacturer employees.

However, in that picture, my impression is that the gentleman is British. Jacket and tie combination and style and the shirt style.

Question: Have you read Terrill Clements "American Volunteer Group Colours and markings. It was published by Osprey but was originally privately published research.

Edited August 20, 2011 by Steven Eisenman

[Kari Lumppio]

Hello!

All aluminium is not equal. There is bare aluminium and there is clad aluminum. Their need for surface protection against corrosion is and was different. One could take steel and stainless as an analogy. Early WW2 alclad was still relatively new material though not rarity.

Many people have never seen bare aircraft grade aluminum simply because it is always primered or otherwise protected. Cladding is simply taken surface protection by mangling thin layer of pure (unalloyed) aluminum on the surface of core alloyed sheet. This is what makes the aluminium sheet shiny ("natural metal finish") while bare aluminium is more like matt grey. Structurally the materials are in essence the same and parts made from either are interchangeable. Just that the bare aluminium part is protected - practically always this means primered (and often painted too) - and alclad many times is not.

That Northrop did not prime when two layers was specified may or may not mean any thing. If the specification was made with bare aluminium material in mind yes then corrosion inhibiting primer (zinc chromate) would be needed. If the material meanwhile was changed to clad aluminum (better supply etc.) it would not need surface protection more so on internal surfaces. I wonder if these contract and specification did not have clausule for that (alclad material needs not to be primered)? What becomes to money saving which did cost more: alclad compared to bare with priming? Labor cost being the key there rather than material costs, I guess.

Same thing with that P-40 assembly line. My take is that the wings are made from both materials in question. The primered sheets/areas are made from bare aluminium and the blue (shop protection) are alclad. The parts may have been manufactured in different times. Tangentially to this theme I remember seeing a photo from Republic factory in a book showing some 1,5 m (5 feet) high stack of fuselage side panels for P-47. If the sheet thicknes was say 1,5 mm (~1/16 inch) there was parts for one thousand Thunderbolts on that pallet on the photo! The P-40 primered wing leading edge parts may simply have been manufactured earlier on and stored. Formed aluminum parts have to be annealed to 0-state and formed before they harden again. Maybe at that time 0-state alclad material was not available? Therefore the mixed contruction later with clad aluminum.

Perhaps this all is too much engineer thoughts, but at least I do not see anything odd if an aircraft has both primered and nonprimered parts. It all depends.

Regards,

Kari

[HBBates]

Hello Kari your point about "All aluminum is not equal" is valid and I assume in regards to my second post above

However it begs the point ....

If you see in the first photo chromate green paint on the wing where the bolt on landing gear faring will go...

Why in the second photo do you see a "gray" on the wing around where the bolt on landing gear faring is? ....

That "gray" is either aluminum cleaned of all overspray paint and or coating

Or a "gray" paint sprayed on before the bolt on landing gear faring is put in place...

So for what logical reason would you bother to scrub that small one area around the landing gear faring of any paint/coating when it going to get painted over with the underside camo paint anyway like the rest of the wing you did not bother to scrub of paint and or coating?

I would say the more logically idea is it a simple overspray of "gray" paint for the under wing skin in and underwhere the landing gear faring will go

So occam's razor whats the more simple …over sprayed "gray" painted on , or paint/coating scrubbed off?

Edited August 20, 2011 by HBBates

[HBBates]

Question: Have you read Terrill Clements "American Volunteer Group Colours and markings. It was published by Osprey but was originally privately published research.

Yes, a few years back

[Kari Lumppio]

...

Why in the second photo do you see a "gray" on the wing around where the bolt on landing gear faring is? ....

...

So for what logical reason would you bother to scrub that small one area around the landing gear faring of any paint/coating when it going to get painted over with the underside camo paint anyway like the rest of the wing you did not bother to scrub of paint and or coating?

I would say the more logically idea is it a simple overspray of "gray" paint for the under wing skin in and underwhere the landing gear faring will go

So occam's razor whats the more simple …over sprayed "gray" painted on , or paint/coating scrubbed off?

Hello!

Honestly I did not bother the lack of overspray at all. I did not even notice it. Now that you mention it my line of thought is that the formed landing gear fairing was painted before it was riveted in place. No overspray. Like I tried to say it would be nothing uncommon that different parts of aircraft are actually manufactured several months apart from each other, even years. If so, bare aluminum parts would need primer application for the time in storage, too. If I am wrong, so be it. I don't really care.

With Best Regards,

Kari

[Test Graham]

You are right that not all parts are necessarily closely contemporary, but I'd have thought it very unlikely that parts for these early P-40s were manufactured years apart, or even months, if only because of the short time between the production decision and delivery. Such parts were made in small batches - manufacture of specific parts in large numbers are what lead to massive waste when Ford attempted to apply its own mass production methods to the B-24. Aircraft change too rapidly: there is a continuous stream of small modifications and any excess parts to the previous standard have only scrap value. The US were to clamp down on this and introduce the block number system - eg P-51D-5, D-10, etc - which only permitted modifications in specific steps, but this was not until considerably later. It could also lead to effort having to be put into "upgrading" of "new" aircraft, but this could be linked to the specific needs of different theatres.

This is not to say that it can't happen, particularly in times with much lower production rates. We had some sets of Strikemaster wings unfinished from a batch that had failed to find buyers. They sat in their jigs at the back of a hangar, and every now and then some desultory work was done on them if the main line slowed for some reason. The eventual buyer was apparently not too impressed by the resulting build quality.

[Work In Progress]

FM100 Hue Test[/url]

It's fun. I scored 0 in the test (you don't want a high score).

Fascinating, and somewhat depressing. I've done it twice now and got 91 each time, which seems very poor. I have always flown through Ishihara testing for adequate colour vision for aircrew licensing and was quite surprised that I was so bad.

[Nick Millman]

Fascinating, and somewhat depressing. I've done it twice now and got 91 each time, which seems very poor. I have always flown through Ishihara testing for adequate colour vision for aircrew licensing and was quite surprised that I was so bad.

Sorry! The Ishihara testing is for colour blindness but acuity to hue gradiation is something more subtle and, forgive the pun, less black and white! There are several modern tests, applied in various professions, to rate colour perception beyond the question of colour blindness. Some transitional colour spaces, blue to green is one, but also brown to green and grey to brown, are tricky and acuity can determine perception to either side. Too many modellers I feel presume that what they see in colour is what others see - or more often what they think they should see! When this presumption is combined with digitally transmitted colour images (sometimes passed through multiple reproduction processes) where the colour on display might not be faithful to the original paint colour, and probably isn't, the potential issues are compounded, but many appear to blissfully disregard this reality.

It's relevance to this thread is the way in which colour photography picks up these very subtle pale blue-greens, almost tinted greys, under various illuminants, and the presumption that the results faithfully represent the original paint colour. Terrill Clements' research has been mentioned, but in the Osprey book cited he writes as follows:-

"The lower surface camouflage of the AVG's Tomahawks is even more interesting. While British contracting officers would likely have specified the complex greenish colour known as Sky at the time these aircraft were ordered, the best colour photographs and film of AVG Tomahawks indicate that their lower surfaces were in fact painted light grey. It appears that other American manufacturers had themselves employed a range of light blues, greys and greens when first coming to grips with the new requirement for Sky undersurfaces in mid-1940".

"As yet no clear explanation for this anomaly has been found. Perhaps American manufacturers simply misunderstood British requirements that often rendered the name as 'Sky Type S Grey'. Indeed the observed light grey is remarkably similar to British Sky Grey. Or perhaps the requirements of other customers, or evolving British specifications for tropical schemes, were a factor. In any event, another existing American military colour, Aircraft Grey (later designated ANA 512), is an excellent match for the British Sky Grey and the observed colour on the bottom of the AVG's Tomahawks."

With the greatest respect to Mr Clements that is not research but just perception and speculation. He might have gone on to mention that not only did the "British contracting officers" specify Sky but the US manufacturers also recorded its application (or at least the application of its equivalents) in their factory documentation and in the documentation sent to end users. Since many colour photographs exist where British Sky (on RAF aircraft) also appears to be a light grey - or even an off-white - even before considering the effects of oxidisation and chalking - this is hardly conclusive stuff. Unfortunately for the hypothesis there are also colour photographs of AVG Tomahawks where the under surface colour appears much closer to Sky-type pale blue-greens.

The questions to be asked here are:-

1. Is the "light grey" apparent in colour photographs really light grey? (In other words is there any other evidence for it as a 'light grey' paint?)

2. If so, why was it chosen to match a requirement for duck egg blue (or Sky) when paints more closely resembling that were available and are documented as having being applied?

3. And if so, why was its use on P-40 (and other) aircraft not noted and recorded by contemporary observers in the UK writing and illustrating specifically on colour themes (and whose work includes references to the appearance of Tomahawks recorded by serial number)?

I don't think that any of these questions have been answered adequately by those promoting the possibility, beyond speculations like those of Mr Clements. What they tend to do is argue against what is known on the grounds that it probably wasn't done. In other words the Curtiss drawings showing DuPont paint colour numbers and names and the proven existence of DuPont's 71-021 Sky Type S Grey paint colour (and its appearance) are of no significance. Creating a speculation that light grey paint might have been used because US manufacturing practices were haphazard seems just that - a speculation. And it doesn't seem entirely valid to cite non-compliance in process with the deliberate substitution of a completely different paint colour to that required and expected. It is perhaps more likely that the use of a light grey paint (if we believe that) was for operational production expediency with some kind of tacit approval. But there seems to be no documentary evidence for that (yet) beyond the somewhat enigmatic minutes of the JAC meetings, and which again are an expression of intention rather than of what was actually done.

A supplementary question - and perhaps the most important one - is could the Sky-equivalent colours appear like light greys in colour photographic images and to observers? The answer is yes but there seems to be a persistent belief in knowing Sky when we see it in whatever forms or media and disregarding the question of degradation.

That may leave us with a "can of worms" but I think it more reasonably leaves us to choose between the probable and the possible. It might not rule out the possibility of light grey but it certainly shouldn't rule out the probability of a Sky (or duck egg blue/green) equivalent colour like DuPont's 71-021 either.

Edited August 21, 2011 by Nick Millman

[HBBates]

Hi Nick

On a side note to my post above ...wheel well finish color

The P40 was some what diffrent in it landing gear set up in that you had a opening in the wing for only the wheel but the gear strut was on the outer wing skin then had a bolt on gear faring to cover it

In my post above, from what is seen in the photos, I speculate that:

US Army spec for the P40, the wheel well opening in the wing and area ON the outer wing skin in and under the bolt on landing gear faring is to be painted in a chromate

But

UK (or just Curtiss' own) spec for the Tomahawk, the wheel well opening in the wing is to be painted in a chromate but the the outer wing skin in and under the bolt on landing gear faring will be paint in underside camo color like the rest of the underside

Do you know of an doc to support that idea because as a modeler what area gets painted what (a chromate vs a camo color) is something to pin down

Edited August 21, 2011 by HBBates

[gingerbob]

Hume, again let me applaud your analysis of photo evidence- whether you're right on all counts or not, you've definitely shown me a thing or two (aside from some great photos!), and you've also stirred up my sometimes latent interest in the Hawk family.

Nick, well stated. I can understand the deductions made by students when the documentary evidence had not yet come to light- there is plenty of (apparent) evidence for US aircraft having a variety of underside colours on aircraft meant for Britain, and in the absence of other information, colour photos seem to me to be a good source of clues, even if not completely reliable. I am less able to understand continued faith in the "light grey" theory now that the documentary evidence has accumulated (and perhaps better reproduction of the photos, or more of them).

bob

[Nick Millman]

Hi Nick

On a side note to my post above ...wheel well finish color

The P40 was some what diffrent in it landing gear set up in that you had a opening in the wing for only the wheel but the gear strut was on the outer wing skin then had a bolt on gear faring to cover it

In my post above, from what is seen in the photos, I speculate that:

US Army spec for the P40, the wheel well opening in the wing and area ON the outer wing skin in and under the bolt on landing gear faring is to be painted in a chromate

But

UK (or just Curtiss' own) spec for the Tomahawk, the wheel well opening in the wing is to be painted in a chromate but the the outer wing skin in and under the bolt on landing gear faring will be paint in underside camo color like the rest of the underside

Do you know of an doc to support that idea because as a modeler what area gets painted what (a chromate vs a camo color) is something to pin down

Sorry Hume, I can't confirm this. Frustratingly even good photographs of the Tomahawk usually have this area in deep shadow and even on colour photos it is impossible to be certain. Construction photos show that the undercarriage was assembled prior to major component painting so I suspect this area was finished in a protective coating rather than the external camo finish. I doubt that it was re-painted which would have been difficult with all the undercart gubbins in place. I have not seen any reference to protective finishes of this area in any formal documents.

Btw, as an aside generally, Steven's characterisation of the thrust of Meekins book on the BAC and Lend Lease has sent me back to it and after a re-read I do not read into it what he does. On the contrary I get the impression of significant co-operation, the free exchange of ideas and considerable effort by the US manufacturers to get things right. Even for the B-29 jigs issue he has mentioned it is apparent that the USAAF adopted British practice to improve the situation and there is even mention of Dupont working closely with the manufacturer and British representatives for one particular technical paint solution. The acceptance procedure for contract purchased aircraft appears to have been rigorous, with anomalies either rectified or formally reported. Like John I would prefer a more specific and exampled argument to support the suggestion of poor quality control rather than the "last word" soundbites we are getting.

However, having said that, the book does not specifically address the question of camouflage paint finishes so the whole thing is somewhat moot in that respect anyway.

I have some more to add about RAF/AVG Tomahawk finishes, what Terrill Clements says and some contemporaneous observations but I'm going to post it on my blog, linked to this thread.

Regards

Nick

[HBBates]

Construction photos show that the undercarriage was assembled prior to major component painting so I suspect this area was finished in a protective coating rather than the external camo finish. I doubt that it was re-painted which would have been difficult with all the undercart gubbins in place.

Hi Nick

That what just keeps bugging me in the second photo, I would expect to see a protective coating (a cromate green/yellow of some kind) peeking out from around the gear faring on the wing but you don't, not a bit of cromate green/yellow (on the gear faring yes but not on the lower wing skin)

But there is clearly some color difference peeking out from around the gear faring (a gray looking color) that different than the majority of the medal on the unpainted wing and so that what I would expect to see on the wing skin inside the faring

Like you said "re-painted which would have been difficult with all the undercart gubbins in place" so do your final finish first of the wing skin where the faring and gear will go, then put the gear and faring in place after (and no worry about overspray outside the area the faring will go as it get painted over later)

The other idea that the "gray looking color" around the gear faring is just medal scrubed of it protective coating just around that area...why would you do that for that one area? that unpainted wing has protective coating and paint overspray from prefinish all over it, look around the gun covers in the front of the wing ..that looks be prefinish overspray of the camo green????

The second photo in my Post #27 remind me of a model in progress you also see prefinish overspray all over it till it done

Edited August 22, 2011 by HBBates

[Nick Millman]

Hume, have you noticed that a whiteish-grey (or perhaps aluminised) paint was applied on undercarriage components? The area around the fairing appears to be similar. The IWM colour photograph is interesting because the undercarriage leg and wheel hub are painted blue, but it is not the same blue as the Azure under surface - instead a slightly greenish or turquoise blue.

Regards

Nick

[HBBates]

Hume, have you noticed that a whiteish-grey (or perhaps aluminised) paint was applied on undercarriage components? The area around the fairing appears to be similar. The IWM colour photograph is interesting because the undercarriage leg and wheel hub are painted blue, but it is not the same blue as the Azure under surface - instead a slightly greenish or turquoise blue.

Regards

Nick

Hmmm that a thought If you look at the google life P40 /Tomahawk color photos sets you do see all the unpainted aircraft on the ramp look to have wheel hub covers in a silver paint...the US Army painted one all have green painted wheel hub covers....

Edited August 22, 2011 by HBBates

[Fernando]

Before discussing whether this pale blue-green is actually blue or green here is an online test you can take to assess your own colour acuity:-

FM100 Hue Test

It's fun. I scored 0 in the test (you don't want a high score).

Hi, Nick,

It s fun indeed! Scored a "3"...

Fernando

[Chuck1945]

Jeebers, I thought I had them all arranged rather well, but the score was 41. So much for my ability to judge color

[mhaselden]

Woohoo!! I got a Zero. Do I get a prize?

[tango98]

Me too!

[Test Graham]

Humph! 4. I'd have liked a guide to where I went wrong, the one on show didn't help at all.

I was doing great until I realised there was more than one bar.....

[Troy Smith]

Woohoo!! I got a Zero. Do I get a prize?

yeah, his wingman on your tail ......takatakatak.... Sorry, couldn't resist especially with your avatar...

Your prize is the assurance that you have the abilty to distiguish between subtle colour gradients. This should get it's own separate post.

On my first casual try on a not so great 14" monitor I got 91! as I always thought I had good colour vision, a 2nd try got me 14 .

The next day on a better 17" monitor i got 0 which cheered me up, but took a good 5 careful minutes.

T

[mhaselden]

You can't see it in the avatar but there are 2 more Ki-43s heading towards the subject aircraft. The pilot led them a merry dance at ever-decreasing altitude until they eventually pulled away and he landed. His groundcrew stopped counting the bullet holes when they got to 70.