Doing some research for a diorama of Little Boy Bomb loading on Tinian, I noticed the US Navy (O-5 and above) personnel involved wore "scrambled eggs" on their peaked cap bills. None of the US Army/Army AirCorps did.

I further couldn't find any pictures of US Officers' caps in WWII thus adorned...........with the exception of General MacArthur. Was this a uniform enhancement designated after the war?