Must have been the "SS-class."
He told me a story about how some guys in his unit found one of those big three-axle open cars the Nazi bigwigs used to ride around in, hidden in a haystack in western Germany somewhere -- it was all tricked out for the upper crust of the Reich with flag fixtures, just like in your posted photo. I think he told me it was a Daimler-Benz. (They also drove Auto Union [Audi] and maybe Bayerische Motoren Werke [sp. -- BMW], which were all semi-statal companies. Add the thoroughly Nazi Volkswagen, and you have the present fleet.)
Those American airmen drove the dog out of that big Benz -- had a real blast, roaring up and down the Autobahn at 100 mph.