France and Germany were aviation leaders, when the US was … not so much.
Germany arguably broke the sound barrier in 1944, and their rockets were going into space, depending on how “space” is defined. They had very good designers, and the technology specialists that followed our troops closely during the war were especially impressed with the wind tunnels. Far beyond anything we had at the time. They disassembled all of that sort of stuff and sent it to the US.
They were also pioneering in aviation or space medicine. The problem with that is they used prisoners of war to experiment on.
How long does it take someone to freeze to death in the ocean? “Well let’s find out”. If you notice modern life vests or flotation devices, they keep the neck area well above the water, as much heat is lost there. Guess how they figured that out? By killing people.
Hubertus Strughold was one of many “paperclip” personnel brought to the US. I think there might have been an Air Force clinic named after him. Kinda wacky.
P-47’s were breaking the sound barrier in WW2 during dives.