Are the US Navy's floating aircraft carriers of the 1930's "Warbirds"???
Last Monday at the Smithsonian Udvar-Hazy Center was the USS Akron's (ZRS-4) F9C Sparrowhawk:

Why do you think they choose this insignia?

...and in 1932

BTW: If you haven't made a visit to the Udvar-Hazy Center you're really missing out!!!