While looking for pictures of the Lafayette Escadrille Sioux head, I came across fabric that was auctioned off last year (for $2,300) at this site:
Lafayette Escadrille Airplane Fabric - Cowan's Auctions
The Sioux head is well rendered, and consistent with some others that I have seen. It is on a red background, painted over plain fabric (I don't see any sign of a lower layer of paint). The auctioneer claimed "Condition: The fabric is original. The paintwork rendered is contemporary," and "This item was originally on display in the 1970s at
the U.S. Air Force Museum in Atwater, California." I assume that "the U.S. Air Force Museum" is the Castle Air Museum, though U.S. Air Force does sound more impressive.
I am curious what forum members think about it. Is this an authentic piece of WWI aircraft fabric? Was there anyone in the Lafayette Escadrille that had a red fuselage with a Sioux head insignia?
Steve