It's pretty obvious. It doesn't even look like a propeller.
I always thought it looked like the Bavarian Flag.
2014 BMW ///M5 Individual Frozen Grey, Silverstone Full Merino, Piano Black, Exec Pkg, Drivers assistance plus, LED Pkg, Bang and Olufsen, 20" 343M Forged Alloy Wheels
Upgrades: Eisenmann Sport with M Performance Carbon tips, Dinan anti-roll bars, Bel StiR+, ALP
2015 Jaguar F-Type R Coupe
2015 Mercedes-Benz C300 Sport