(Sorry, Buffnut - I'm an unrepentant enabler!
Hi Fubar,
This was a show for Congress and VIPs to show just how ready we were as war was brewing up in Europe. There are a bunch more outdoors photos showing other aircraft in the Life magazine collections (though I don't have the links) that might give a hint of the colors.
Camouflage responsibility had been at Wright Field, but the Materiel folks balked at Arnold's demand for permanent camouflage finishes, so he transferred the authority to the Air Corps Board at Maxwell in 1939. Maxwell would have been as close to any experimental camouflage division as we had at the time. They were already coming close to OD/Neutral Gray, but the Wright Field colors were what was available in January 1940.
Here are some more pix:
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