Dear Wildsau,
Actually the photo posted by mjfur show the wings of the Ta 152 H-0 W.Nr. 150010 still under restoration at the Paul E. Garber facility; property of NASM. This aircraft has been re-painted several times during its life and the livery shown nowadays is not the original one, but was applied during evaluation flights by american personnel. Lower surfaces of the wings are not in their original colour and they are not bare metal either. Even the
Balkenkreuze are fake. For example, if you look at the last photo posted by mjfur, you can see the difference in colour between the interior of the wheel well (that is bare metal) and the surface of the wing (that has been repainted). That said, we can not say with certainty how the actual color was when the aircraft was assembled. Only the restoration team could eventually work it out.
Anyway, we can still find what was the original material. The red code that can be seen in the wheel well was indeed applied by the manufacturer to specify the alloy composition. It should be an aluminium alloy, but knowing that code would allow us to know it with more accuracy... Unfortunately I never found the correnspondence of that code
. The code is 3126.9. Have you got any idea? Thanks!
(Note that the picture below has increased contrast and saturation to better see the code. The actual outer colour is grey)
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